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Articles 29281 - 29310 of 41159

Full-Text Articles in Engineering

Enhancing Brand Equity Through Flow: Comparison Of 2d Versus 3d Virtual World, Fiona Fui-Hoon Nah, Brenda Eschenbrenner, David Dewester Dec 2010

Enhancing Brand Equity Through Flow: Comparison Of 2d Versus 3d Virtual World, Fiona Fui-Hoon Nah, Brenda Eschenbrenner, David Dewester

Research Collection School Of Computing and Information Systems

This research uses the theory of flow to examine the effect of 2D versus 3D virtual world environments on brand equity and use intention. The results suggest that a 3D virtual world environment has both positive (indirect) and negative (direct) effects on brand equity. The positive, indirect effect of the 3D virtual world environment occurs through feelings of telepresence and enjoyment, both of which contribute positively to brand equity and, in turn, induces a higher behavioral intention. The negative, direct effect can be explained using distraction-conflict theory, where attentional conflict is faced by users of a highly interactive and rich …


Topical Summarization Of Web Videos By Visual-Text Time-Dependent Alignment, Song Tan, Hung-Khoon Tan, Chong-Wah Ngo Dec 2010

Topical Summarization Of Web Videos By Visual-Text Time-Dependent Alignment, Song Tan, Hung-Khoon Tan, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

Search engines are used to return a long list of hundreds or even thousands of videos in response to a query topic. Efficient navigation of videos becomes difficult and users often need to painstakingly explore the search list for a gist of the search result. This paper addresses the challenge of topical summarization by providing a timeline-based visualization of videos through matching of heterogeneous sources. To overcome the so called sparse-text problem of web videos, auxiliary information from Google context is exploited. Google Trends is used to predict the milestone events of a topic. Meanwhile, the typical scenes of web …


Map Estimation For Graphical Models By Likelihood Maximization, Akshat Kumar, Shlomo Zilberstein Dec 2010

Map Estimation For Graphical Models By Likelihood Maximization, Akshat Kumar, Shlomo Zilberstein

Research Collection School Of Computing and Information Systems

Computing a maximum a posteriori (MAP) assignment in graphical models is a crucial inference problem for many practical applications. Several provably convergent approaches have been successfully developed using linear programming (LP) relaxation of the MAP problem. We present an alternative approach, which transforms the MAP problem into that of inference in a finite mixture of simple Bayes nets. We then derive the Expectation Maximization (EM) algorithm for this mixture that also monotonically increases a lower bound on the MAP assignment until convergence. The update equations for the EM algorithm are remarkably simple, both conceptually and computationally, and can be implemented …


Web-Based Intelligent Computational Argumentation Based Conflict Resolution In Air Traffic Management, Xiaoqing Frank Liu, Ravi Santosh Arvapally, Hojong Baik, Rubal Wanchoo Nov 2010

Web-Based Intelligent Computational Argumentation Based Conflict Resolution In Air Traffic Management, Xiaoqing Frank Liu, Ravi Santosh Arvapally, Hojong Baik, Rubal Wanchoo

Computer Science Faculty Research & Creative Works

Collaborative decision making (CDM) is a process of reaching consensus on a potential solution of an issue through the evaluation of the different possible alternatives. the web-Based intelligent computational argumentation system allows concerned stakeholders to post their arguments on different alternatives, assign weights and priorities to the arguments and reach the most favorable alternative using fuzzy intelligent techniques over the Internet. Exchange of information among the stakeholders improves the collaboration and drives towards the collective intelligence. in this paper, we show how our tool facilitates resolution of conflicts in air traffic management. It could enhance the Ground Delay Program (GDP) …


Electrochemical Detection For The Corrosion Of Reinforcing Steel In Concrete During Immersion And Drying Cycles, Bing-Li Jia, Fa-He Cao, An-Na Chen, Jian-Qing Zhang Nov 2010

Electrochemical Detection For The Corrosion Of Reinforcing Steel In Concrete During Immersion And Drying Cycles, Bing-Li Jia, Fa-He Cao, An-Na Chen, Jian-Qing Zhang

Journal of Electrochemistry

The corrosion behavior of reinforcing steel in concrete under dry-wet cycle condition has been studied by electrochemical noise(EN) compared with the electrochemical impedance spectroscopy(EIS),SEM micrographs and EDS.The statistical method has been employed to analyze the EN data of reinforcing steel in concrete,which revealed three different corrosion stages of reinforcing steel in concrete,including the dissolution of the passive film,the active corrosion and the cumulation of corrosion product.The wavelet transform has also been employed,which indicated that steel in concrete with pH 1 is associated with uniform corrosion,while steel in concrete with pH 3 and pH 7 are associated with localized corrosion,such as …


Study On Preparing Technology And Corrosion Resistance Of Ti/Zr Based Chromium-Free Chemical Conversion Coating On Zinc Electroplating Layer, Yong Guan, Jian-Guo Liu, Chuan-Wei Yan Nov 2010

Study On Preparing Technology And Corrosion Resistance Of Ti/Zr Based Chromium-Free Chemical Conversion Coating On Zinc Electroplating Layer, Yong Guan, Jian-Guo Liu, Chuan-Wei Yan

Journal of Electrochemistry

In this paper,we obtained environmental-friendly chromium-free chemical conversion coating on the non-cyanide alkaline zinc electroplating layer by employing the optimized Ti/Zr based conversion technique.At the same time,the performances of the Ti/Zr based conversion coating were compared with chromate colour passivation coating.The corrosion resistances of the conversion coatings were investigated by using neutral salt spray(NSS) test,potentiodynamic polarization and electrochemical impedance spectroscopy(EIS).The results showed that the white rust appeared after 96 hours when the NSS test was performed on the Ti/Zr based conversion coating,which was close to the corrosion resistance rating of chromate colour passivation coating.Compared with the chromate passivation coating,the Ti/Zr …


Preparation And Characterization Of The Silane-Phosphonic Acid Composite Passivation Coating For Electrogalvanized Steel, Yong Guan, Jian-Guo Liu, Chuan-Wei Yan Nov 2010

Preparation And Characterization Of The Silane-Phosphonic Acid Composite Passivation Coating For Electrogalvanized Steel, Yong Guan, Jian-Guo Liu, Chuan-Wei Yan

Journal of Electrochemistry

A new silane-phosphonic acid composite passivation coating process has been developed for the protection of electrogalvanized steel based on N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane(AAPTMS),γ-(2,3-epoxypropoxy)propyltrimethoxy-silane(GPTMS) and 1-hydroxy ethylidene-1,1-diphosphonic acid(HEDP).The results of X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR),potentiodynamic polarization scan,electrochemical impedance spectroscopy(EIS) and neutral salt spray(NSS) tests indicated that the major structure of the prepared silane-phosphonic acid composite passivation coating consisted mainly of Si—O—Si and Si—O—P bonds.The area of white rust was not more than 5% of the total panal after 120 h NSS test,which could be compared favourably with the chromate colour passivation coating.However,the corrosion reaction on the anode of the silane-phosphonic acid composite passivation …


The Roles Of The Width Of Gas/Liquid/Solid Three-Phase Boundary Zone Of Dispersion Water Films In Atmospheric Corrosion Of Metals, Jia Wang, Jing Jiang Nov 2010

The Roles Of The Width Of Gas/Liquid/Solid Three-Phase Boundary Zone Of Dispersion Water Films In Atmospheric Corrosion Of Metals, Jia Wang, Jing Jiang

Journal of Electrochemistry

The roles of TPB(Three-Phase Boundary) width in the corrosion processes of metals under dispersed water films were investigated by electrochemical techniques combined with contact angle measurement.It is found that both cathodic limiting current density and corrosion current density linearly increases with increasing the TPB width,confirming the important role of TPB width in gas/liquid/solid multiphase corrosion systems.Based on above results,the effect of water film thickness on atmospheric corrosion rate was quantitatively evaluated by the TPB width.


Photoelectrochemical Properties Of N, S, And Cl Modified Nano Tio2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du Nov 2010

Photoelectrochemical Properties Of N, S, And Cl Modified Nano Tio2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du

Journal of Electrochemistry

The nitrogen(N),sulfur(S) and chlorine(Cl) modified nano TiO2 thin films were prepared by adding Ti(O-n-Bu)4 as the precursor into concentrated HNO3,H2SO4 and HCl Solutions,respectively,on different substrates in a sol-gel process.The photoelectrochemical performances of N,S and Cl modified nano TiO2 thin films have been studied by UV-vis(DRS),photocurrent curves,EIS and OCP-time curves.N-modified TiO2 nano films show better surface structure,which helps to improve the quantum efficiency of nano TiO2 thin films.


Hydrothermal Reduction Synthesis Of Lifepo4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen Nov 2010

Hydrothermal Reduction Synthesis Of Lifepo4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen

Journal of Electrochemistry

The cathode materials of LiFePO4 were prepared via a hydrothermal reduction method using FeCl3 as Fe source and iron as a reducing agent.The results showed that ferric salt could be reduced to ferrous salt completely under the hydrothermal condition and pure-phase LiFePO4 was obtained based on the test results of XRD and FTIR.Carbon-coated LiFePO4 was synthesized by pyrolysisng glucose at high temperature.The morphologies of pure LiFePO4 displayed cluster-like while the LiFePO4/C displayed sphere-like particles.The electrochemical test showed that the LiFePO4/C had good rate performance,while LiFePO4 delivered much lower discharge capacity.


Corrosion Electrochemical Behavior Of Am60 Magnesium Alloys In Automobile Engine Coolants, Ling-Jie Li, Sha Wang, Yin Xiao, Jun Lan, Jing-Lei Lei, Sheng-Tao Zhang, Fu-Sheng Pan Nov 2010

Corrosion Electrochemical Behavior Of Am60 Magnesium Alloys In Automobile Engine Coolants, Ling-Jie Li, Sha Wang, Yin Xiao, Jun Lan, Jing-Lei Lei, Sheng-Tao Zhang, Fu-Sheng Pan

Journal of Electrochemistry

The polarization measurements and electrochemical impedance spectroscopy(EIS) were used to study the corrosion electrochemical behavior of AM60 magnesium alloys in three kinds of commercial coolants for automobile engine.Results show that the tested commercial coolants are slightly corrosive to AM60 magnesium alloys and their corrosivity varies from coolant to coolant.The coolant C is the least corrosive among the studied commercial coolants and the coolant A is more corrosive than the coolant B and C.The coolant C appears to be the most promising coolant for automobile engine made by magnesium alloys.The coolant resistivity plays an important role in the corrosion of AM60 …


Study Of The 11-Ferrocenylalkanethiol Redox-Induced Structure Changes By Flow-Injection Electrochemical Surface Plasmon Resonance, Xiu-Juan Xiao, Yong-Hui He, Juan Xiang, Bin Ren Nov 2010

Study Of The 11-Ferrocenylalkanethiol Redox-Induced Structure Changes By Flow-Injection Electrochemical Surface Plasmon Resonance, Xiu-Juan Xiao, Yong-Hui He, Juan Xiang, Bin Ren

Journal of Electrochemistry

Redox-induced orientation changes of self-assembled monolayers(SAMs) of 11-ferrocenylundecanethiol(FcC11SH) were studied by the flow-injection electrochemical surface plasmon resonance(FI-EC-SPR).Results indicated that there existed two mechanisms concerning the redox-induced structure change of the self-assembled monolayer of ferrocenylalkanethiols:the electrostatic repulsion between the positively charged surface and the ferricenium cation and that among the cations led to a decrease in the tilt angle of the alkanethiol chain;upon Fc oxidation,the Fc group rotated from a tilted conformation to a position where the cyclpentyldiene plane became perpendicular to the electrode.


Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang Nov 2010

Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang

Journal of Electrochemistry

The PbO2 anodes were prepared on platinum from fluoroborate media and its doped solutions by electrodeposition technique.Elecchemical and pysicochemical properties of these PbO2 films were studied by cyclic voltammetry methods,XRD and SEM.The results showed that the presence of BF4-increased PbO2 electrodeposition rate;the prepared lead dioxide consisted of β-PbO2;the preferential orientation of crystals and surface morphology were affected a lot by doping F-and Fe3+.The FB/F-Fe-PbO2 electrode exhibited regular-shaped layers with compact morphology.Furthermore,increasing current density also change the preferential orientation of PbO2 crystals.


The Sol-Gel Synthesis And Electrochemical Performance Of Li3V2(Po4)3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai Nov 2010

The Sol-Gel Synthesis And Electrochemical Performance Of Li3V2(Po4)3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai

Journal of Electrochemistry

Li3V2(PO4)3/C was synthesized by sol-gel method with citric acid as chelate and C sources. Physical and electrochemical performances of as-prepared materials were characterized through XRD, SEM and galvanostatic charge-discharge tests,etc. The results showed that products produced by calcining at 800 ℃ for 12 h had a single phase crystal structure and relatively small particle sizes with uniform distribution. At 0.1 C, 0.5 C and 1 C, the initial specific discharge capacities were 153.0, 143.1 and 130.6 mAh·g-1, respectively, and capacity efficiencies were 93.1%, 85.4% and 77.3% after 50 cycles, respectively. …


Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu Nov 2010

Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu

Journal of Electrochemistry

The Nafion117/SiO2 composite membrane was prepared by sol-gel method.The results showed that,during composite membrane preparation process,the ratio of MeOH and TEOS did not affect the penetration rate of VO2+ basically,however,the lowest permeability of 427×10-9cm2/s in the membrane was achieved while hydrolysis time was 10 min and natural drying for 24 h after hydrolysis,which reduced by 52 times than that in Nafion117 membrane.The SEM tests proved that SiO2 grains grew bigger in the composite membrane during the natural drying,and most of the holes in Nafion117 were filled.Single cell test showed the battery power efficiency was improved …


Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang Nov 2010

Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang

Journal of Electrochemistry

The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile(MeCN),propylene carbonate(PC) and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate(TBAPF6)/MeCN or TBAPF6/PC electrolyte.However,the CV curves in 0.1 mol·L-1 TBAPF6/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L-1 TBAPF6/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak …


Initial Stage Of Atmospheric Corrosion Of Ndfeb(M35) In A Simulated Marine Atmosphere, Chun-Ling Li, Yuan-Tai Ma, Ying Li, Fu-Hui Wang Nov 2010

Initial Stage Of Atmospheric Corrosion Of Ndfeb(M35) In A Simulated Marine Atmosphere, Chun-Ling Li, Yuan-Tai Ma, Ying Li, Fu-Hui Wang

Journal of Electrochemistry

This study detailed the atmospheric corrosion behaviour of sintered NdFeB(M35) in a simulated marine atmosphere with 80% relative humidity(RH).The dissolution and subsequent reaction of NaCl particles cause the attack of NdFeB.The corrosion presented three representative types:if the electrolyte covered magnetic phase and Nd-rich phase,the Nd-rich phase was corroded firstly due to galvanic effect;if the electrolyte covered magnetic phase,magnetic phase was corroded along the grain boundary;if the electrolyte located near the position of defects,corrosion progressed along with the defect because of low concentration of oxygen inside the defect.With corrosion progressing,local corrosion areas were mutually connected,with Nd-rich phase and grain boundary being …


Effect Of Cldh On Rebar Corrosion Behavior In Chloride Contaminated Neutral Pore Solutions, Yu-Ming Tang, Le Niu, Yu Zuo Nov 2010

Effect Of Cldh On Rebar Corrosion Behavior In Chloride Contaminated Neutral Pore Solutions, Yu-Ming Tang, Le Niu, Yu Zuo

Journal of Electrochemistry

he effect of calcined LDH-MgAl-CO3 on rebar corrosion behavior in chloride ion contaminated neutral concrete pore solutions was investigated in this paper.Corrosion potentials of rebars in pore solutions after treatment with CLDH were higher than before treatment.According to polarization tests,passivated region of rebars in pore solutions after treatment with CLDH was found apparently instead of activation.EIS tests showed that CLDH made the impedance of specimens increase.The measurements of pH and chloride ion concentration after treatment indicated that / of pore solutions decreased by 4~5 magnitude orders.


Pooling For Horizontal Wells: Can They Teach An Old Dog New Tricks?, Bruce M. Kramer Nov 2010

Pooling For Horizontal Wells: Can They Teach An Old Dog New Tricks?, Bruce M. Kramer

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

74 pages.

This paper was originally published as:

Bruce M. Kramer, “Pooling for Horizontal Wells: Can They Teach an Old Dog New Tricks?,” 55 Rocky Mt. Min. L. Inst. 8-1, § 8.05 (2009).


Slides: Shale Drilling And Completions, William Fleckenstein Nov 2010

Slides: Shale Drilling And Completions, William Fleckenstein

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: William Fleckenstein, BP Adjunct Professor in the Petroleum Department and Director of PERFORM Research, Colorado School of Mines, Golden, CO, and Managing Partner of Fleckenstein, Eustes & Associates

20 slides


Slides: Transforming And Disrupting: Shale Gas And Oil In U.S. Energy Supply, Richard Nehring Nov 2010

Slides: Transforming And Disrupting: Shale Gas And Oil In U.S. Energy Supply, Richard Nehring

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: Richard Nehring, Nehring Associates, Colorado Springs, CO

15 slides


Agenda: Shale Plays In The Intermountain West: Legal And Policy Issues, University Of Colorado Boulder. Natural Resources Law Center Nov 2010

Agenda: Shale Plays In The Intermountain West: Legal And Policy Issues, University Of Colorado Boulder. Natural Resources Law Center

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

This one-day symposium to be held at the Grand Hyatt hotel in Denver will address the technology, economics, environmental impacts, and regulatory issues associated with shale gas development in the Rocky Mountain region. The purpose of this event is to facilitate productive dialogue among a wide range of stakeholders and interested parties to guide policy decisions.


Slides: Development Of Shale: Water Resource Concerns And Policy Considerations, Katy Dunlap Nov 2010

Slides: Development Of Shale: Water Resource Concerns And Policy Considerations, Katy Dunlap

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: Katy Dunlap, Eastern Water Project Director, Trout Unlimited, Inc., Burdett, NY

24 slides


Slides: The Here And Now Of U.S. Nat Gas, Michelle Michot Foss Nov 2010

Slides: The Here And Now Of U.S. Nat Gas, Michelle Michot Foss

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: Michelle Michot Foss, Chief Energy Economist, Center for Energy Economics, Bureau of Economic Geology, University of Texas, Austin, TX

12 slides


Slides: Water And Development Of Unconventional Oil And Gas Resources, Judy Jordan Nov 2010

Slides: Water And Development Of Unconventional Oil And Gas Resources, Judy Jordan

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: Judy Jordan, Oil & Gas Liaison, Garfield County, Rifle, CO

21 slides


Slides: Shale And Air Quality: The View From The Other Side, Jeremy Nichols Nov 2010

Slides: Shale And Air Quality: The View From The Other Side, Jeremy Nichols

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: Jeremy Nichols, Climate & Energy Program Director, WildEarth Guardians, Denver, CO

18 slides


Slides: U.S. Shale Gas: Resources, Reserves And $$$, John B. Curtis Nov 2010

Slides: U.S. Shale Gas: Resources, Reserves And $$$, John B. Curtis

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: John B. Curtis, Professor of Geology and Geological Engineering and Director of the Potential Gas Agency, Colorado School of Mines, Golden, CO

17 slides


Slides: Evolving Policy On Shale Plays, John Martin Nov 2010

Slides: Evolving Policy On Shale Plays, John Martin

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: John Martin, Crowell & Moring, LLP, Washington, DC

17 slides


Experimental Evaluation Of Transmission Link Characteristics In Body Area Networks, Apoorva Kiran Pandya Nov 2010

Experimental Evaluation Of Transmission Link Characteristics In Body Area Networks, Apoorva Kiran Pandya

School of Computing: Dissertations, Theses, and Student Research

Recent advances in digital electronics, embedded systems, and wireless communications have led the way to a new class of distributed Wireless Sensor Networks (WSNs). A Body Area Network (BAN) is a WSN consisting of miniaturized, low-power, autonomous, wireless biosensors, which are seamlessly placed or implanted in the human body to provide an adaptable and smart health care system. The possible applications of BAN are in health care services and medicine, assisting persons with disabilities, and entertainment and sports. The nodes in a BAN generally use IEEE 802.15.4 radios which have low- power consumption and are relatively immune to interference. In …


Synthesis Of Mild–Hard Aao Templates For Studying Magnetic Interactions Between Metal Nanowires, Jin-Hee Lim, Aurelian Rotaru, Seong-Gi Min, Leszek Malkinski, John B. Wiley Nov 2010

Synthesis Of Mild–Hard Aao Templates For Studying Magnetic Interactions Between Metal Nanowires, Jin-Hee Lim, Aurelian Rotaru, Seong-Gi Min, Leszek Malkinski, John B. Wiley

Physics Faculty Publications

The sequential application of mild and hard anodization techniques in the fabrication of porous aluminamembranes allows one to decrease the number of continuous pores in anodized aluminium oxide (AAO) templates. Initially, standard mild anodization techniques were used to create porous templates with 100 nm interpore distances and 70 nm pore diameters. Hard anodization treatment on the same membrane then produced interpore distances of about 265 nm with diameters of 110 nm. At the interface between the two anodization steps, many of the mild-side pores were terminated to create a mild–hard membrane (Mi–Ha AAO) where the functional interpore distances were 200–300 …