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Simulating Data To Study Performance Of Finite Mixture Modeling And Clustering Algorithms, Ranjan Maitra, Volodymyr Melnykov 2010 Iowa State University

Simulating Data To Study Performance Of Finite Mixture Modeling And Clustering Algorithms, Ranjan Maitra, Volodymyr Melnykov

Statistics Publications

A new method is proposed to generate sample Gaussian mixture distributions according to prespecified overlap characteristics. Such methodology is useful in the context of evaluating performance of clustering algorithms. Our suggested approach involves derivation of and calculation of the exact overlap between every cluster pair, measured in terms of their total probability of misclassification, and then guided simulation of Gaussian components satisfying prespecified overlap characteristics. The algorithm is illustrated in two and five dimensions using contour plots and parallel distribution plots, respectively, which we introduce and develop to display mixture distributions in higher dimensions. We also study properties of the ...


Swine Producer Appraisal Of The Community Assessment Model For Odor Dispersion (Cam), John C. Tyndall, Jay D. Harmon, Steven J. Hoff 2010 Iowa State University

Swine Producer Appraisal Of The Community Assessment Model For Odor Dispersion (Cam), John C. Tyndall, Jay D. Harmon, Steven J. Hoff

Agricultural and Biosystems Engineering Publications

The community assessment model (CAM) for odor dispersion is a tool to assist in the siting of swine production facilities. CAM considers the size and type of a swine production system, local historical weather conditions, and odor control implementation. It predicts the number of hours of exposure to various levels of odor, by month, for each receptor in a given community. A follow-up survey of all CAM users since 2005 was conducted. The survey was designed to provide: 1) formative feedback for programming adjustments to improve Extension efficiency, usability, and reduce costs; and 2) summative feedback used to provide an ...


Polystyrene-Supported Aluminum Chloride As An Efficient And Reusable Catalyst For Condensation Of Indole With Various Carbonyl Compounds, Bahman Tamami, Amir Nasrolahi Shirazi, Kaveh Parvanak Borujeni 2010 Shiraz University

Polystyrene-Supported Aluminum Chloride As An Efficient And Reusable Catalyst For Condensation Of Indole With Various Carbonyl Compounds, Bahman Tamami, Amir Nasrolahi Shirazi, Kaveh Parvanak Borujeni

Pharmacy Faculty Articles and Research

Crosslinked polystyrene-supported aluminum chloride (PS-AlCl3) is a stable, recyclable and environmental friendly heterogeneous catalyst for the condensation of indole with aldehydes and ketones to afford diindolylmethanes. In addition, PS-AlCl3 shows satisfactory selectivity in the reaction of mixtures of an aldehyde and a ketone with indole. Although AlCl3 is a water sensitive, corrosive and environmentally harmful compound, PS-AlCl3 is a stable and water-tolerant species. The mild reaction conditions, short reaction times, easy work-up, high to excellent yields, chemoselectivity, reuse of the catalyst for at least ten times without significant change in its catalytic activity, low cost, and easy preparation and handling ...


Do Online Reviews Reflect A Product's True Perceived Quality? An Investigation Of Online Movie Reviews Across Cultures, Noi Sian KOH, Nan Hu, Eric K. Clemons 2010 Singapore Management University

Do Online Reviews Reflect A Product's True Perceived Quality? An Investigation Of Online Movie Reviews Across Cultures, Noi Sian Koh, Nan Hu, Eric K. Clemons

Research Collection School Of Information Systems

When does the reported average of online ratings match perceived average assessment? We apply behavioral theory to capture intentions in rating online movie reviews in two dissimilar countries - China and the United States. We argue that consumers' rating behaviors are affected by cultural influences. Based on data collected from imdb.com and douban.com, we found significant differences across raters from these two different cultures. Additionally, we examined how cultural elements influence rating behavior for a hybrid culture - Singapore. Under-reporting bias occurs when consumers with extreme opinions are more likely to report their opinions than consumers with moderate reviews, resulting ...


Anonymous Query Processing In Road Networks, Kyriakos MOURATIDIS, Man Lung YIU 2010 Singapore Management University

Anonymous Query Processing In Road Networks, Kyriakos Mouratidis, Man Lung Yiu

Research Collection School Of Information Systems

The increasing availability of location-aware mobile devices has given rise to a flurry of location-based services (LBSs). Due to the nature of spatial queries, an LBS needs the user position in order to process her requests. On the other hand, revealing exact user locations to a (potentially untrusted) LBS may pinpoint their identities and breach their privacy. To address this issue, spatial anonymity techniques obfuscate user locations, forwarding to the LBS a sufficiently large region instead. Existing methods explicitly target processing in the euclidean space and do not apply when proximity to the users is defined according to network distance ...


An Empirical Analysis Of Mobile Voice Service And Sms: A Structural Model, Youngsoo KIM, Rahul Telang, William B. Vogt, Ramayya Krishnan 2010 Singapore Management University

An Empirical Analysis Of Mobile Voice Service And Sms: A Structural Model, Youngsoo Kim, Rahul Telang, William B. Vogt, Ramayya Krishnan

Research Collection School Of Information Systems

In addition to the wireless telephony boom, a similar exponentially increasing trend in wireless data service—for example, short message service (SMS)—is visible as technology advances. We develop a structural model to examine user demand for voice service and SMS. Specifically, we measure the own- and cross-price elasticities of these services. The cross-price elasticity is of significant importance because marketing activities are critically influenced by whether the goods are substitutes or complements. The research context poses significant econometric challenges due to three-part tariffs and sequential discrete plan choice and continuous quantity choice decisions. Using detailed individual consumption data of ...


Delay, Cost And Infrastructure Tradeoff Of Epidemic Routing In Mobile Sensor Networks, Shan Zhou, Lei Ying, Srikanta Tirthapura 2010 Iowa State University

Delay, Cost And Infrastructure Tradeoff Of Epidemic Routing In Mobile Sensor Networks, Shan Zhou, Lei Ying, Srikanta Tirthapura

Electrical and Computer Engineering Conference Papers, Posters and Presentations

This paper studies the delay, cost and infrastructure tradeoff of epidemic routing in mobile sensor networks. We consider a mobile sensor network with M mobiles and B static base stations. The mobile sensors collect information when moving around and need to report the information to the base stations. Three different epidemic routing schemes --- target epidemic routing, uncontrolled epidemic routing and controlled epidemic routing --- are analyzed in this paper. For each of the three schemes, we characterize the scaling behaviors of the delay, which is defined to be the average number of time slots required to deliver a message, and the ...


Analysis Avoidance Techniques Of Malicious Software, Murray Brand 2010 Edith Cowan University

Analysis Avoidance Techniques Of Malicious Software, Murray Brand

Theses: Doctorates and Masters

Anti Virus (AV) software generally employs signature matching and heuristics to detect the presence of malicious software (malware). The generation of signatures and determination of heuristics is dependent upon an AV analyst having successfully determined the nature of the malware, not only for recognition purposes, but also for the determination of infected files and startup mechanisms that need to be removed as part of the disinfection process. If a specimen of malware has not been previously extensively analyzed, it is unlikely to be detected by AV software. In addition, malware is becoming increasingly profit driven and more likely to incorporate ...


Personal Exposure Of Children To Formaldehyde In Perth, Western Australia, Victoria S. Lazenby 2010 Edith Cowan University

Personal Exposure Of Children To Formaldehyde In Perth, Western Australia, Victoria S. Lazenby

Theses: Doctorates and Masters

Formaldehyde is a common air pollutant that tends to be found in elevated concentrations in indoor air. Exposure to formaldehyde has the potential to impact on respiratory health, particularly amongst sensitive individuals and populations, including children. Children spend most of their time indoors at home, however, there are very little data on the contribution of formaldehyde concentrations in homes to personal exposure in children. The principal aim of this cross sectional study was to investigate whether the domestic environment is the most significant source of personal exposure of formaldehyde in children. Forty-one primary school children (aged between 8 and 12 ...


Climate Change, Sustainable Development, And Ecosystems: 2009 Annual Report, John Dernbach 2009 Widener Univesity Law School

Climate Change, Sustainable Development, And Ecosystems: 2009 Annual Report, John Dernbach

John C. Dernbach

No abstract provided.


Transport Studies Of Nh4no3 Doped Methyl Cellulose Electrolyte, Siti Rohana Majid, Shuhaimi N. E. A., Teo L. P., Arof A. K. 2009 University of Malaya

Transport Studies Of Nh4no3 Doped Methyl Cellulose Electrolyte, Siti Rohana Majid, Shuhaimi N. E. A., Teo L. P., Arof A. K.

Siti Rohana Majid

This work reports on the transport properties of NH4NO3 doped methyl cellulose (MC) polymer electrolyte. The polymer electrolyte films were prepared by the technique of solvent casting. The highest room temperature conductivity of MC doped with 25 wt.% NH4NO3 is 2.10 +/- 0.37 x 10(-6) S cm(-1). Conductivity-temperature relationship obeys the Vogel-Tamman-Fulcher (VTF) rule from which the glass transition temperature, T-g was evaluated. The mobility, p and number density of charge carrier, n were calculated using the Rice and Roth model. (C) 2010 Elsevier B.V. All rights reserved.


Imputation Procedures For American Community Survey Group Quarters Small Area Estimation, Chandra Erdman, Chaitra Nagaraja 2009 Fordham University

Imputation Procedures For American Community Survey Group Quarters Small Area Estimation, Chandra Erdman, Chaitra Nagaraja

Chaitra H Nagaraja

No abstract provided.


Technology For The Organic Chemist: Three Exploratory Modules, John Esteb, LuAnne McNulty, John Magers, Paul Morgan, Anne Wilson 2009 Butler University

Technology For The Organic Chemist: Three Exploratory Modules, John Esteb, Luanne Mcnulty, John Magers, Paul Morgan, Anne Wilson

John Esteb

The ability to use computer-based technology is an essential skill set for students majoring in chemistry. This exercise details the introduction of appropriate uses for this technology in the organic chemistry series. The incorporation of chemically appropriate online resources (module 1), scientific databases (module 2), and the use of a chemical drawing program (module 3) are detailed here.

Note: Link is to the article in a subscription database available to users affiliated with Butler University. Appropriate login information will be required for access. Users not affiliated with Butler University should contact their local librarian for assistance in locating a copy ...


Making The States Full Partners In A National Climate Change Effort: A Necessary Element For Sustainable Economic Development, John Dernbach, Robert McKinstry, Thomas Peterson 2009 Widener Univesity Law School

Making The States Full Partners In A National Climate Change Effort: A Necessary Element For Sustainable Economic Development, John Dernbach, Robert Mckinstry, Thomas Peterson

John C. Dernbach

This article explains why states and localities need to be full partners in a national climate change effort based on federal legislation or the existing Clean Air Act. A large share of reductions with the lowest cost and the greatest co-benefits (e.g., job creation, technology development, reduction of other pollutants) are in areas that a federal cap-and-trade program or other purely federal measures will not easily reach. These are also areas where the states have traditionally exercised their powers—including land use, building construction, transportation, and recycling. The economic recovery and expansion will require direct state and local management ...


Enumeration Schemes For Permutations Avoiding Barred Patterns, Lara Pudwell 2009 Valparaiso University

Enumeration Schemes For Permutations Avoiding Barred Patterns, Lara Pudwell

Lara K. Pudwell

No abstract provided.


Strategies For Preparing Computer Science Students For The Multicore World, Elizabeth Shoop, et al 2009 Macalester College

Strategies For Preparing Computer Science Students For The Multicore World, Elizabeth Shoop, Et Al

Elizabeth Shoop

No abstract provided.


Characteristics Of Methyl Cellulose-Nh4no3-Peg Electrolyte And Application In Fuel Cells, Siti Rohana Majid, Shuhaimi N. E. A., Alias N. A., Kufian M. Z., Arof A. K. 2009 University of Malaya

Characteristics Of Methyl Cellulose-Nh4no3-Peg Electrolyte And Application In Fuel Cells, Siti Rohana Majid, Shuhaimi N. E. A., Alias N. A., Kufian M. Z., Arof A. K.

Siti Rohana Majid

We report the viability of methyl cellulose (MC) as a membrane in a polymer electrolyte membrane fuel cell (PEMFC). Methyl cellulose serves as the polymer host, ammonium nitrate (NH4NO3) as the doping salt and poly(ethylene glycol) (PEG) as plasticizer. Conductivity measurement was carried out using electrochemical impedance spectroscopy. The room temperature conductivity of pure MC film is is (3.08 +/- 0.63) x 10(-11)S cm(-1). The conductivity increased to (2.10 +/- 0.37) x 10(-6)S cm(-1) on addition of 25 wt.% NH4NO3. By adding 15 wt.% of PEG 200 to the highest conducting ...


Shock Wave Formation On Turbulent Coanda Surfaces, T. Dowd, Caroline Lubert 2009 James Madison University

Shock Wave Formation On Turbulent Coanda Surfaces, T. Dowd, Caroline Lubert

Caroline P Lubert

No abstract provided.


Exit Frequency Matrices For Finite Markov Chains, Andrew Beveridge, László Lovász 2009 Macalester College

Exit Frequency Matrices For Finite Markov Chains, Andrew Beveridge, László Lovász

Andrew Beveridge

No abstract provided.


Exponential Growth Rate Of Paths And Its Connection With Dynamics, Pengfei Zhang 2009 Northwestern University

Exponential Growth Rate Of Paths And Its Connection With Dynamics, Pengfei Zhang

Pengfei Zhang

No abstract provided.


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