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2004

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Articles 151 - 180 of 3869

Full-Text Articles in Physical Sciences and Mathematics

Acknowledgements, The Mcnair Team Dec 2004

Acknowledgements, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

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Consistency Results For The Roc Curves Of Fused Classifiers, Kristopher S. Bjerkaas Dec 2004

Consistency Results For The Roc Curves Of Fused Classifiers, Kristopher S. Bjerkaas

Theses and Dissertations

The U.S. Air Force is researching the fusion of multiple classifiers. Given a finite collection of classifiers to be fused, one seeks a new classifier with improved performance. An established performance quantifier is the Receiver Operating Characteristic (ROC) curve, which allows one to view the probability of detection versus the probability of false alarm in one graph. Previous research shows that one does not have to perform tests to determine the ROC curve of this new fused classifier. If the ROC curve for each individual classifier has been determined, then formulas for the ROC curve of the fused classifier exist …

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Field Evidence For Geophysical Detection Of Subsurface Zones Of Enhanced Microbial Activity, Eliot A. Atekwana, Estella A. Atekwana, Franklyn D. Legall, R. V. Krishnamurthy Dec 2004

Field Evidence For Geophysical Detection Of Subsurface Zones Of Enhanced Microbial Activity, Eliot A. Atekwana, Estella A. Atekwana, Franklyn D. Legall, R. V. Krishnamurthy

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Geochemical data from closely spaced vertical intervals in a hydrocarbon-impacted aquifer were used to assess the relationship between bulk conductivity and zones of enhanced microbial activity. The bulk conductivity was measured using in situ vertical resistivity probes. Microbial activity was verified using terminal electron acceptors (nitrate, sulfate, iron, and manganese), dissolved inorganic carbon (DIC), and major ion chemistry. Peaks in bulk conductivity in the aquifer overlapped with zones where nitrates and sulfates were depleted, total petroleum hydrocarbon, iron, manganese, dissolved ions, and DIC were elevated, suggesting a link between higher electrical conductivity and zones of enhanced microbial activity stimulated by …

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Teaching Fractions, Natalie Miles Dec 2004

Teaching Fractions, Natalie Miles

Mahurin Honors College Capstone Experience/Thesis Projects

Because fractions are a vital part of mathematics instruction in schools and can be found in real life, it is important that all students understand and be able to utilize them. Teachers should choose strategies that will work best for their individual students, taking into account the various ways their students learn and the fraction knowledge students already possess. To effectively teach fractions, teachers must find ways to prompt student interest. Teachers can accomplish this through the use of technology. games. and manipulatives. Effective teachers must take into account the cultural diversity of their students. Teachers must be able to …

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The Characterization Of Nanosized Nickel-Zinc Ferrites Synthesized Within Reverse Micelles Of Ctab/1-Hexanol/Water Microemulsion, Vuk Uskoković, Miha Drofenik, Irena Ban Dec 2004

The Characterization Of Nanosized Nickel-Zinc Ferrites Synthesized Within Reverse Micelles Of Ctab/1-Hexanol/Water Microemulsion, Vuk Uskoković, Miha Drofenik, Irena Ban

Pharmacy Faculty Articles and Research

Stoichiometric nanocrystalline nickel–zinc ferrites were synthesized by a reverse micelle method following a multi-microemulsion approach. Different pH values were chosen for the alkali precipitating reaction during the synthesis of different powders. Synthesized, as-dried and subsequently calcined powders were characterized in terms of their magnetic properties. XRD analyses and specific-surface area measurements were used to determine the average particle sizes of the synthesized samples. DCS and TGA measurements were performed to reveal the phase transitions within the samples at elevated temperatures, whereas TEM was used to view and record the microstructure of the nanosized ferrite samples. A possible mechanism of the …

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A Tga/Ftir And Mass Spectral Study On The Thermal Degradation Of Bisphenol A Polycarbonate, Bok Nam Jang, Charles A. Wilkie Dec 2004

A Tga/Ftir And Mass Spectral Study On The Thermal Degradation Of Bisphenol A Polycarbonate, Bok Nam Jang, Charles A. Wilkie

Chemistry Faculty Research and Publications

The thermal degradation of polycarbonate under nitrogen was studied using TGA/FTIR, GC/MS and LC/MS as a function of mass loss. The gases evolved during degradation were inspected by in situ FTIR and then the evolved products were collected and analysed using FTIR, GC–MS and LC–MS. The structures of the evolved products are assigned on the basis of FTIR and GC/MS results. The main thermal degradation pathways follow chain scission of the isopropylidene linkage, and hydrolysis/alcoholysis and rearrangement of carbonate linkages. In the case of chain scission, it was proposed that methyl scission of isopropylidene occurs first, according to the bond …

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Coordinate Conditions For A Uniformly Accelerated Or Static Plane Symmetric Metric, Preston Jones, Lucas Wanex Dec 2004

Coordinate Conditions For A Uniformly Accelerated Or Static Plane Symmetric Metric, Preston Jones, Lucas Wanex

Publications

The coordinate conditions for three exact solutions for the metric components of a coordinate system with constant acceleration or of a static plane symmetric gravitational field are presented. First, the coordinate condition that the acceleration of light is constant is applied to the field equations to derive the metric of a coordinate system of constant acceleration. Second, the coordinate conditions required to produce the metrics of Rindler and Lass are applied to the field equations to calculate the components of these two metrics and the coordinate velocities and coordinate accelerations for light of these two metrics are compared to the …

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Teacher In The Spotlight, Aaron Beaumont Dec 2004

Teacher In The Spotlight, Aaron Beaumont

Lake Union Herald

No abstract provided.

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The Effect Of Naocl, Ca(Oh)2, Mta And Mtad On Root Dentin Fracture Resistance, Sunil Ilapogu Dec 2004

The Effect Of Naocl, Ca(Oh)2, Mta And Mtad On Root Dentin Fracture Resistance, Sunil Ilapogu

Loma Linda University Electronic Theses, Dissertations & Projects

Various materials are used for the treatment of immature teeth that have been subjected to trauma or decay. It is not well established what effect these materials may have on the immature root dentin. A concern would be the resistance to fracture of the remaining root dentin. The purpose of this study was to compare the resistance of fracture of bovine teeth treated with sodium hypochlorite, calcium hydroxide, gray MTA and gray MTA in conjunction with MTAD after certain periods of time. One hundred and ninety five freshly extracted, intact bovine incisors were prepared using a modified Haapasalo and Orstavik …

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Values Of Mobile Commerce To Customers, Keng Siau, H. Sheng, Fiona Fui-Hoon Nah Dec 2004

Values Of Mobile Commerce To Customers, Keng Siau, H. Sheng, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

This research studies the values of m-commerce using a qualitative means-ends approach, called Value-Focused Thinking. The conceptual foundation for this research is the Work System Framework. By interviewing both current and potential m-commerce users, we captured the values of m-commerce and develop a means-ends objective network to illustrate the relationships among these values. As one of the first empirical research to assess the values of m-commerce, this research contributes to an increased understanding of m-commerce. The means-ends objective network also serves as a theoretical foundation for future research in m-commerce. For practitioners, our findings highlight the concerns and issues of …

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Neutron Multiplicity Measurements For The Afci Program Quarterly Progress Report September-December 2004, Denis Beller Dec 2004

Neutron Multiplicity Measurements For The Afci Program Quarterly Progress Report September-December 2004, Denis Beller

Transmutation Sciences Physics (TRP)

The U.S. Advanced Fuel Cycle Initiative (AFCI) is a program to develop economic and environmental methods to reduce the impact of waste from commercial nuclear fuel cycles. One concept for near-complete destruction of waste isotopes from used nuclear fuel is accelerator driven transmutation. High-power accelerators would be used to produce high-energy charged particles, which then collide with heavy metal targets to create a cascade of neutrons. These neutrons then cause a nuclear chain reaction in subcritical systems. Fission neutrons then transmute fissile waste isotopes as well as other problematic isotopes such as technetium-99 and iodine-129. To design these systems, complex …

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On The Design Of Efficient Priority Rules For Secured Creditors: Empirical Evidence From A Change In Law, Clas Bergström, Theodore Eisenberg, Stefan Sundgren Dec 2004

On The Design Of Efficient Priority Rules For Secured Creditors: Empirical Evidence From A Change In Law, Clas Bergström, Theodore Eisenberg, Stefan Sundgren

Cornell Law Faculty Publications

This article assesses the effect of a reduction in secured creditor priority on distributions and administrative costs in liquidating bankruptcy cases by reporting the first empirical study of the effect of a priority change. Priority reform had redistributive effects in liquidating bankruptcy. As expected, average payments to general unsecured creditors were significantly higher after the reform than before the reform and payments to secured creditors decreased. Reform did not increase the size of the pie to be distributed in bankruptcy. Nor did it increase the direct costs of bankruptcy.

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Automatic Model Structuring From Text Using Biomedical Ontology, Joshi R., Li X., Ramachandaran S., Tze-Yun Leong Dec 2004

Automatic Model Structuring From Text Using Biomedical Ontology, Joshi R., Li X., Ramachandaran S., Tze-Yun Leong

Research Collection School Of Computing and Information Systems

Bayesian Networks and Influence Diagrams are effective methods for structuring clinical problems. Constructing a relevant structure without the numerical probabilities in itself is a challenging task. In addition, due to the rapid rate of innovations and new findings in the biomedical domain, constructing a relevant graphical model becomes even more challenging. Building a model structure from text with minimum intervention from domain experts and minimum training examples has always been a challenge for the researchers. In the biomedical domain, numerous advances have been made which may make this dream a possibility now. We are currently trying to build a general …

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A Credit-Based Distributed Protocol For Long-Term Fairness In Ieee 802.11 Single-Hop Networks, Yan Wu, Sonia Fahmy Dec 2004

A Credit-Based Distributed Protocol For Long-Term Fairness In Ieee 802.11 Single-Hop Networks, Yan Wu, Sonia Fahmy

Department of Computer Science Technical Reports

No abstract provided.

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Robust And Distributed Computation Of Aggregates In Wireless Sensor Networks, Jen-Yeu Chen, Gopal Pandurangan, Dongyan Xu Dec 2004

Robust And Distributed Computation Of Aggregates In Wireless Sensor Networks, Jen-Yeu Chen, Gopal Pandurangan, Dongyan Xu

Department of Computer Science Technical Reports

No abstract provided.

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Unstructured Peer-To-Peer Networks For Sharing Processor Cycles, Asad Awan, Ronaldo A. Ferreira, Suresh Jagannathan, Ananth Y. Grama Dec 2004

Unstructured Peer-To-Peer Networks For Sharing Processor Cycles, Asad Awan, Ronaldo A. Ferreira, Suresh Jagannathan, Ananth Y. Grama

Department of Computer Science Technical Reports

No abstract provided.

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Recommender Systems For Multimedia Libraries: An Evaluation Of Different Models For Datamining Usage Data, Raquel Oliveira Araujo Dec 2004

Recommender Systems For Multimedia Libraries: An Evaluation Of Different Models For Datamining Usage Data, Raquel Oliveira Araujo

Computer Science Theses & Dissertations

Many recommender systems exist today to help users deal with the large growth in the amount of information available in the Internet. Most of these recommender systems use collaborative filtering or content-based techniques to present new material that would be of interest to a user. While these methods have proven to be effective, they have not been designed specifically for multimedia collections. In this study we present a new method to find recommendations that is not dependent on traditional Information Retrieval (IR) methods and compare it to algorithms that do rely on traditional IR methods. We evaluated these algorithms using …

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Diel Foraging Behavior Of American White Pelicans ()Pelecanus Erythrorhynchos) On Experimental Aquaculture Ponds , Scott J. Werner Dec 2004

Diel Foraging Behavior Of American White Pelicans ()Pelecanus Erythrorhynchos) On Experimental Aquaculture Ponds , Scott J. Werner

United States Department of Agriculture Wildlife Services: Staff Publications

Videography and night vision equipment were used to observe the diurnal and nocturnal activities of American white pelicans (Pe1ecanus erythrorhynchos) (N= 6) foraging on three experimental (0.04 ha) channel catfish (Ictalurus punctatus) aquaculture ponds in March 2001. Captive pelicans spent most time foraging per hour from 1700 through 2300 h (CST). No foraging was observed from 0700 through 0800 h. Fish captures per hour were greatest from 1700 through 1900 h. On average, captive pelicans (N = 5) consumed 1.0 ± 0.2 kg of catfish per bird per day during the 10-d foraging …

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Alligators As West Nile Virus Amplifiers, Kaci Klenk, Jamie Snow, Katrina Morgan, Richard Bowen, Michael Stephens, Falacia Foster, Paul Gordy, Susan Beckett, Nicholas Komar, Duane Gubler, Michael Bunning Dec 2004

Alligators As West Nile Virus Amplifiers, Kaci Klenk, Jamie Snow, Katrina Morgan, Richard Bowen, Michael Stephens, Falacia Foster, Paul Gordy, Susan Beckett, Nicholas Komar, Duane Gubler, Michael Bunning

United States Department of Agriculture Wildlife Services: Staff Publications

Recent evidence suggests that American alligators (Alligator mississippiensis) may be capable of transmitting West Nile virus (WNV) to other alligators. We experimentally exposed 24 juvenile alligators to WNV parenterally or orally. All became infected, and all but three sustained viremia titers >5.0 log10 PFU/mL (a threshold considered infectious for Culex quinquefasciatus mosquitoes) for 1 to 8 days. Noninoculated tankmates also became infected. The viremia profiles and multiple routes of infection suggest alligators may play an important role in WNV transmission in areas with high population densities of juvenile alligators.

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Current And Historic Freshwater Mollusk Distributions Of The Upper Coosa River Basin, Sabrina Felicitas Novak Dec 2004

Current And Historic Freshwater Mollusk Distributions Of The Upper Coosa River Basin, Sabrina Felicitas Novak

Masters Theses and Doctoral Dissertations

This thesis contains summary data from all Tennessee Aquarium Research Institute (TNARI) survey activities of freshwater mollusks within the upper Coosa River basin (UCRB) from 1998 to 2003. Survey results of 4 different TNARI studies, a total of 515 separate collections, are presented. My component of the study examined 231 sites primarily in the Coosawattee and Etowah river basins in 2002 - 2003. In addition to the 231 sites surveyed, a large database was constructed from natural history museum records to evaluate temporal changes in species richness and distribution across the UCRB. Of 43 mussel and 33 snail species reported …

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The Kinetics Following Photolysis Of Nitrosyl Bromide, Lori A. Mahoney Dec 2004

The Kinetics Following Photolysis Of Nitrosyl Bromide, Lori A. Mahoney

Theses and Dissertations

One candidate for the development of a tunable laser in the mid-infrared for use as a defensive countermeasure against passive sensors exploits the nitric oxide (NO) transition at 5.4 μm. However, the difficulty with this mechanism is that when bromine (Br2) and NO are present in a mixture, nitrosyl bromide (BrNO) is also created. The absorption bands present in BrNO complicate the design of such a laser. This thesis determines the forward and reverse rate constants of the reaction of Br2 and NO to form BrNO following the photolysis of BrNO using Fourier Transform Infrared absorption spectroscopy. …

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Forensic Analysis Of Digital Image Tampering, Jonathan R. Sturak Dec 2004

Forensic Analysis Of Digital Image Tampering, Jonathan R. Sturak

Theses and Dissertations

The use of digital photography has increased over the past few years, a trend which opens the door for new and creative ways to forge images. The manipulation of images through forgery influences the perception an observer has of the depicted scene, potentially resulting in ill consequences if created with malicious intentions. This poses a need to verify the authenticity of images originating from unknown sources in absence of any prior digital watermarking or authentication technique. This research explores the holes left by existing research; specifically, the ability to detect image forgeries created using multiple image sources and specialized methods …

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Statistical Tools For Digital Image Forensics, Alin C. Popescu Dec 2004

Statistical Tools For Digital Image Forensics, Alin C. Popescu

Dartmouth College Ph.D Dissertations

A digitally altered image, often leaving no visual clues of having been tampered with, can be indistinguishable from an authentic image. The tampering, however, may disturb some underlying statistical properties of the image. Under this assumption, we propose five techniques that quantify and detect statistical perturbations found in different forms of tampered images: (1) re-sampled images (e.g., scaled or rotated); (2) manipulated color filter array interpolated images; (3) double JPEG compressed images; (4) images with duplicated regions; and (5) images with inconsistent noise patterns. These techniques work in the absence of any embedded watermarks or signatures. For each technique we …

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The Meyer-Neldel Rule For Diodes In Forward Bias, Ralf Widenhorn, Michael Fitzgibbons, Erik Bodegom Dec 2004

The Meyer-Neldel Rule For Diodes In Forward Bias, Ralf Widenhorn, Michael Fitzgibbons, Erik Bodegom

Physics Faculty Publications and Presentations

We analyzed the temperature dependence of the forward current of a silicon diode. Instead of representing the data in the ordinarily used current versus voltage graph, the currents are plotted for different voltages as a function of the inverse temperature. The constant voltage curves can be fitted linearly and the extrapolations of the fits seem to merge to one common focal point. Hence, we demonstrate that a real diode follows the Meyer-Neldel rule (MNR). It is shown that the MNR is due to a shift of the current from ideal-diode to high-injection-diode behavior. We will argue that the merging of …

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Analysis Of Hostile Network Reconnaissance To Anticipate And Mitigate Network Attacks, Luis Angel Rivera Dec 2004

Analysis Of Hostile Network Reconnaissance To Anticipate And Mitigate Network Attacks, Luis Angel Rivera

Theses and Dissertations

Network security systems today such as current intrusion detection systems, intrusion prevention systems and firewalls are good at reacting to attacks as they occur or shortly after they occur. Current security systems lack the ability to identify and detect the activity that usually precedes an attack. This activity is known as network reconnaissance. In this thesis we have developed a technique that can assist current security systems to detect hostile network reconnaissance to anticipate and mitigate network attacks.

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Risk Perceptions Of Adults In The Town Of Unicoi, Tennessee, Regarding The Possible Building Of A Uranium Enrichment Plant., Shannon Kathleen Sellards Dec 2004

Risk Perceptions Of Adults In The Town Of Unicoi, Tennessee, Regarding The Possible Building Of A Uranium Enrichment Plant., Shannon Kathleen Sellards

Electronic Theses and Dissertations

A prolonged siting controversy for a uranium enrichment facility has occurred in the Town of Unicoi, Tennessee. One hundred-seventy residents of Unicoi were interviewed using a questionnaire regarding the building of a proposed uranium enrichment facility for Unicoi. The questionnaire sought to determine relationships between residents’ risk perceptions and 18 variables. When the Fisher’s exact procedure was applied at α< 0.05, the results indicated several associations. Odds ratio measured the strength of association. Results are reported as crude measures of association. Risk perceptions were influenced by the choice of possible locations for the facility [p=0.0003; OR=32.6]. Residents' risk perceptions were associated with a history of working with nuclear materials [p=0.0476; OR=3.2]. Finally, risk perceptions were associated with residents' beliefs that the nuclear facility would affect their health [p=0.0001; OR=18.8]. These results are discussed in light of risk perception and communication theories.

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The Spectra Of Type Ii Cepheids. Iii. The Hα Line And Helium Emission In Long-Period Stars, Edward G. Schmidt, Dale Johnston, Kevin M. Lee, Shawn Langan, Peter R. Newman, Stephanie A. Snedden Dec 2004

The Spectra Of Type Ii Cepheids. Iii. The Hα Line And Helium Emission In Long-Period Stars, Edward G. Schmidt, Dale Johnston, Kevin M. Lee, Shawn Langan, Peter R. Newman, Stephanie A. Snedden

Department of Physics and Astronomy: Faculty Publications

We have obtained Hα profiles from 175 spectra of 37 Cepheids with periods longer than 8 days. About two-thirds of the stars are likely type II Cepheids. In contrast to the situation among short-period stars, the velocity of Hα relative to the metal-line spectrum is not a useful parameter for distinguishing type I and type II Cepheids. On the other hand, at periods longer than 11 days and shorter than 34 days strong emission is observed in many stars and appears to be a good discriminator of type. On this basis we identify one probable type I Cepheid at a …

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Justilm: Few-Shot Justification Generation For Explainable Fact-Checking Of Real-World Claims, Fengzhu Zeng, Wei Gao Dec 2004

Justilm: Few-Shot Justification Generation For Explainable Fact-Checking Of Real-World Claims, Fengzhu Zeng, Wei Gao

Research Collection School Of Computing and Information Systems

Justification is an explanation that supports the verdict assigned to a claim in fact-checking. However, the task of justification generation is previously oversimplified as summarization of fact-check article authored by professional checkers. In this work, we propose a realistic approach to generate justification based on retrieved evidence. We present a new benchmark dataset called ExClaim for Explainable Claim verification, and introduce JustiLM, a novel few-shot retrieval-augmented language model to learn justification generation by leveraging fact-check articles as auxiliary resource during training. Our results show that JustiLM outperforms in-context learning (ICL)-enabled LMs including Flan-T5 and Llama2, and the retrieval-augmented model Atlas …

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The Value Of Mobile Commerce To Customers, Keng Siau, H. Sheng, Fiona Fui-Hoon Nah Dec 2004

The Value Of Mobile Commerce To Customers, Keng Siau, H. Sheng, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

This research studies the values of m-commerce using a qualitative means-ends approach, called Value-Focused Thinking. The conceptual foundation for this research is the Work System Framework. By interviewing both current and potential m-commerce users, we captured the values of m-commerce and develop a means-ends objective network to illustrate the relationships among these values. As one of the first empirical research to assess the values of m-commerce, this research contributes to an increased understanding of mcommerce. The means-ends objective network also serves as a theoretical foundation for future research in mcommerce. For practitioners, our findings highlight the concerns and issues of …

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U-Commerce: Emerging Trends And Research Issues, H. Galanxhi-Janaqi, Fiona Fui-Hoon Nah Dec 2004

U-Commerce: Emerging Trends And Research Issues, H. Galanxhi-Janaqi, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

Ubiquitous commerce or u-commerce is the combination of traditional e-commerce and wireless, television, voice and silent commerce. U-commerce implies ubiquity, universality, uniqueness and unison. It is not a replacement for other types of commerce, but an extension of them. While bringing many benefits, there are challenges and impediments to overcome. Research is needed to assess the value of u-commerce and to address its related issues and challenges. Questions that need to be addressed are: What is the value of u-commerce? What are the ways to maximize the benefits and value of u-commerce? Is it the right technology and what directions …

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