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Full-Text Articles in Physics

Wiki Leaks Revelations In Global Context—The War Between ‘Right To Publish’ And ‘Ethical Code Of Conduct, Ratnesh Dwivedi Mr Nov 2011

Wiki Leaks Revelations In Global Context—The War Between ‘Right To Publish’ And ‘Ethical Code Of Conduct, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

WikiLeaks is an international non-profit organisation that publishes submissions of private, secret, and classified media from anonymous news sources, news leaks, and whistleblowers. Its website, launched in 2006 under The Sunshine Press organisation claimed a database of more than 1.2 million documents within a year of its launch. WikiLeaks describes its founders as a mix of Chinese dissidents, journalists, mathematicians, and start-up company technologists from the United States, Taiwan, Europe, Australia, and South Africa. Julian Assange, an Australian Internet activist, is generally described as its director. The site was originally launched as a user-editable wiki, but has progressively moved towards …


A Critical Study Of Organizational Communication And Organizational Communication Theories- A Historical Perspective, Ratnesh Dwivedi Mr Nov 2011

A Critical Study Of Organizational Communication And Organizational Communication Theories- A Historical Perspective, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

Organizational Communication is the study that looks at human communication within and outside the organization. Conrad and Poole (1998) break the definition of organizational communication in parts, by first defining communication and then analyses the organization. These researchers define communication as “a process through which people, acting together, create, sustain, and manage meanings through the use of verbal and nonverbal signs and symbols within a particular context” (Conrad and Poole, 1998, p. 5). In the context of this book, Kenyans and their leaders are communicating their views and final decision through the ballot box to elect their third president, during …


Public Accountability And Media : Its Success And Failure In Performing The Role As A Force For Public Accountability, Ratnesh Dwivedi Mr Nov 2011

Public Accountability And Media : Its Success And Failure In Performing The Role As A Force For Public Accountability, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

Media accountability is a phrase that refers to the general (especially western) belief that mass media has to be accountable in the public’s interest - that is, they are expected to behave in certain ways that contribute to the public good. The concept is not clearly defined, and often collides with commercial interests of media owners; legal issues, such as the constitutional right to the freedom of the press in the U.S.; and governmental concerns about public security and order. Several international organizations, like International Freedom of Expression Exchange, Freedom House, International Press Institute, World Press Freedom Committee and the …


Risk-Based Critical Infrastructure Priorities For Emp And Solar Storms, George H. Baker Iii Oct 2011

Risk-Based Critical Infrastructure Priorities For Emp And Solar Storms, George H. Baker Iii

George H Baker

Two electromagnetic phenomena have the potential to create continental-scale disasters. The first, nuclear electromagnetic pulse (EMP), results from a nuclear detonation high above the tropopause. The second, a major solar storm, or "solar tsunami" occurs naturally when an intense wave of charged particles from the sun perturbs the earth's magnetic field. Both phenomena can debilitate electrical and electronic systems necessary for the operation of infrastructure systems and services. One reason why a U.S. protection program has yet to be initiated is that policy makers continue to wrestle with the question of where to begin, given the Department of Homeland Security’s …


Environmental Research With Undergraduates In East Asia: Collaborations In China And Japan, Gary A. Morris, Jon Schoer Oct 2011

Environmental Research With Undergraduates In East Asia: Collaborations In China And Japan, Gary A. Morris, Jon Schoer

Gary A. Morris

China: From 2007-2008 as part of a collaborative research project funded by the ASIANetwork, VU and the VLACD, 5 VU students (2 chemistry, 1 biology, 1 environmental science, and 1 civil engineering) spent 3 weeks in Zhejiang province, China and 7 additional weeks in northwest Indiana comparing and contrasting water quality issues and attitudes in the two regions. While in China, the students interacted with one another and graduate students, faculty, and staff from Zhejiang University and Zhejiang A &F University, and with multiple local & regional officials and residents to collect water quality data and opinions about key water …


Risk-Based Critical Infrastructure Protection Priorities For Emp And Solar Storms, George H. Baker Iii Sep 2011

Risk-Based Critical Infrastructure Protection Priorities For Emp And Solar Storms, George H. Baker Iii

George H Baker

The Commission to Assess the Threat to the United States from Electromagnetic Pulse Attack has provided a compelling case for protecting civilian infrastructure against the effects of EMP. As with protecting infrastructure against any hazard, it will be important to take a risk-based priority approach for EMP, recognizing that it is fiscally impracticable to protect everything. In this regard, EMP is particularly challenging in that it interferes with electrical and electronic data, control, transmission, and communication systems organic to nearly all infrastructures in a simultaneous and wide-scale manner. And, for nuclear burst altitudes of 100s of kilometers, the exposed geography …


Emp: A Brief Tutorial, George H. Baker Iii Jul 2011

Emp: A Brief Tutorial, George H. Baker Iii

George H Baker

A nuclear detonation at altitudes from about 30 to 500 kilometers generates a strong electromagnetic pulse (EMP) that propagates to points on the ground within the line-of-sight of the burst. For bursts above 100 kilometers, electronics can be affected over continental scale areas. The EMP induces large voltages and currents in antennas and cables of electronic systems that will upset operation or damage circuit components if protection measures are not present. The article provides a brief tutorial on EMP environments, effects and protection.


High Power Electromagnetic Weapons: A Brief Tutorial, George H. Baker Iii Jul 2011

High Power Electromagnetic Weapons: A Brief Tutorial, George H. Baker Iii

George H Baker

High power electromagnetic weapons, also referred to as high power radiofrequency (HPRF) weapons, are a type of directed energy weapons. The system effects of high power electromagnetic environments are well recognized by world scientific and military communities. Former CIA Director John Deutch has said that, "the electron is the ultimate precision-guided weapon." In the course of the investigation ofnuclear EMP effects on electronics during the Cold War period, it became evident that garden variety, unprotected electronics would malfunction, in some cases burn out, in the presence of electromagnetic fields in the hundreds to thousands of volts per meter. The EMP …


Vuv Absorption Cross Section Of Benzene, Relevance For Titan’S Atmosphere, F-J. Capalbo, Y. Bénilan, N. Fray, M. Schwell, Et. Es-Sebbar, N. Champion, T. Koskinen, R. Yelle Jul 2011

Vuv Absorption Cross Section Of Benzene, Relevance For Titan’S Atmosphere, F-J. Capalbo, Y. Bénilan, N. Fray, M. Schwell, Et. Es-Sebbar, N. Champion, T. Koskinen, R. Yelle

Dr. Et-touhami Es-sebbar

Saturn's largest satellite, Titan, is the only one in the Solar System known to have a thick N2/CH4, planet like atmosphere. The dissociation of these principal components and the recombination of the products make this atmosphere to be rich in organic compounds of high interest for astrobiology. Solar and stellar occultations observed by the Ultraviolet Imaging Spectrograph (UVIS) on board the Cassini spacecraft can be used to characterize the composition of Titan’s upper atmosphere (400 – 1400 km). The results depend strongly on the knowledge of the molecular absorption cross sections of the atmospheric constituents (Ferradaz et al. 2009). This …


The Penetration Of Social Media In Governance,Political Reforms And Building Public Perception, Ratnesh Dwivedi Mr May 2011

The Penetration Of Social Media In Governance,Political Reforms And Building Public Perception, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

Social media are media for social interaction, using highly accessible and scalable communication techniques. Social media is the use of web-based and mobile technologies to turn communication into interactive dialogue. While we know that social media can play an important role in publicizing political activities such as protests, do we have evidence that such actions have led to substantive political change? Is it possible to develop a set of indicators to more effectively gauge the impact of new technologies and media on questions of political change? That social media can help coordinate large and discrete activities, such as protests and …


Two Faces Of Media While Covering Human Right Activities In India, Ratnesh Dwivedi Mr Apr 2011

Two Faces Of Media While Covering Human Right Activities In India, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

The situation of human rights in India is a complex one, as a result of the country's large size and tremendous diversity, its status as a developing country and a sovereign, secular, democratic republic, and its history as a former colonial territory. The Constitution of India provides for Fundamental rights, which include freedom of religion. Clauses also provide for Freedom of Speech, as well as separation of executive and judiciary and freedom of movement within the country and abroad. In its report on human rights in India during 2010, Human Rights Watch stated India had "significant human rights problems". They …


Characterization Of Continuous Vacuum Ultraviolet Lamps-Implication On The Study Of Methane Photolysis At Lyman Alpha (121.6 Nm), M-C. Gazeau, Y. Benilan, Et. Es-Sebbar, A. Jolly, E. Arzoumanian, N. Fray, H. Cottin Apr 2011

Characterization Of Continuous Vacuum Ultraviolet Lamps-Implication On The Study Of Methane Photolysis At Lyman Alpha (121.6 Nm), M-C. Gazeau, Y. Benilan, Et. Es-Sebbar, A. Jolly, E. Arzoumanian, N. Fray, H. Cottin

Dr. Et-touhami Es-sebbar

Low-temperature hydrogen plasmas are widely used as continuous vacuum ultraviolet irradiation sources in photochemical studies and, in particular, in laboratory simulations of planetary atmospheres. One of the most challenging objectives of such experiments is to retrieve accurate quantitative laboratory data allowing a reliable comparison with theoretical and/or observational ones. This task can only be achieved when the irradiation source delivers a well characterised radiation in terms of flux and wavelength dependency. As an example, we will present a study, developed in the frame of a program dedicated to simulations of Titan’s atmosphere, on methane photolysis at Lyman alpha (121.6 nm). …


Formation Of Hcn And Nh3 As Primary Compounds Of Titan’S Atmosphere Simulations Using N2-Ch4 Afterglow Plasma’’, M-C. Gazeau, Y. Bénilan, E. Arzoumanian, Et. Es-Sebbar, A. Jolly, C.D. Pintassilgo Apr 2011

Formation Of Hcn And Nh3 As Primary Compounds Of Titan’S Atmosphere Simulations Using N2-Ch4 Afterglow Plasma’’, M-C. Gazeau, Y. Bénilan, E. Arzoumanian, Et. Es-Sebbar, A. Jolly, C.D. Pintassilgo

Dr. Et-touhami Es-sebbar

No abstract provided.


Language Discourse- A Critical Analysis Of Michel Focault's Work On Language Discourse With Special Reference To His Masterpiece "The Archeology Of Knowledge", Ratnesh Dwivedi Mr Apr 2011

Language Discourse- A Critical Analysis Of Michel Focault's Work On Language Discourse With Special Reference To His Masterpiece "The Archeology Of Knowledge", Ratnesh Dwivedi Mr

Ratnesh Dwivedi

Discourse generally refers to "written or spoken communication or debate". The following are three more specific definitions: (1) In semantics and discourse analysis: A generalization of the concept of conversation to all modalities and contexts. (2) "The totality of codified linguistic usages attached to a given type of social practice. (E.g.: legal discourse, medical discourse, religious discourse.)" (3) In the work of Michel Foucault, and social theorists inspired by him: "an entity of sequences of signs in that they are enouncements (enoncés)" (Foucault 1969: 141). An enouncement (often translated as "statement") is not a unity of signs, but an abstract …


Epistemic Strategies For Solving Two-Dimensional Physics Problems, Mary Elyse Hing-Hickman Apr 2011

Epistemic Strategies For Solving Two-Dimensional Physics Problems, Mary Elyse Hing-Hickman

Physics Theses & Dissertations

An epistemic strategy is one in which a person takes a piece of knowledge and uses it to create new knowledge. Students in algebra and calculus based physics courses use epistemic strategies to solve physics problems. It is important to map how students use these epistemic strategies to solve physics problems in order to provide insight into the problem solving process.

In this thesis three questions were addressed: (1) What epistemic strategies do students use when solving two-dimensional physics problems that require vector algebra? (2) Do vector preconceptions in kinematics and Newtonian mechanics hinder a student's ability to apply the …


Challenges Before Traditional Media In The Age Of Digital Media-How To Integrate It With Digital Media-The Way Ahead, Ratnesh Dwivedi Mr Mar 2011

Challenges Before Traditional Media In The Age Of Digital Media-How To Integrate It With Digital Media-The Way Ahead, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

You may have heard of digital media, but you may have no idea what it is and how it can help you out when it comes to marketing. It's definitely important that you get up to speed so you can use this to benefit your business. Basically digital media refers to any type of electronic media out there. Today media can be accessed in many ways, including with hand held devices like mobile phones, laptops, desktops, mp3 players, and more.Digital media must be stored in an electronic way, so there is a lot of digital content on the internet today, …


Colloids And Emulsions, Tony Dinsmore Jan 2011

Colloids And Emulsions, Tony Dinsmore

Science and Engineering Saturday Seminars

Colloids and Emulsions.

These materials are very common and are amenable to some nice demonstrations, yet are not part of the usual curriculum. Topics include surface tension (and why droplets are spherical; why shaving cream acts like a solid even though it's made of liquid and gas); Brownian motion and the microscopic origin of heat; the behavior of many particles (phase transitions, how colloidal particles can spontaneously order themselves – an accurate demonstration of how water molecules form ice crystals); what is inside everyday materials.


Apparatus For Demonstrating Longitudinal Wave Pulses, Walter L. Trikosko, Thomas O. Callaway Jan 2011

Apparatus For Demonstrating Longitudinal Wave Pulses, Walter L. Trikosko, Thomas O. Callaway

Faculty Publications

For live classroom demonstrations there are a number of devices that have been used to simulate waves. Some are based upon a design produced by E. S. Ritchie & Sons1 and consist of rods and cams that are activated by turning a crank.2,3 These devices show what transverse and longitudinal waves look like, but they do not allow for the free manipulation of wave parameters and observations of the changes that take place. A simple device can be constructed using elastic bands and straws4 to demonstrate properties of transverse waves.


Understanding Student Pathways In Context-Rich Problems, Pavlo Antonenko, John Jackman, Piyamart Kumsaikaew, Rahul Marathe, Dale Niederhauser, Craig Ogilvie, Sarah Ryan Jan 2011

Understanding Student Pathways In Context-Rich Problems, Pavlo Antonenko, John Jackman, Piyamart Kumsaikaew, Rahul Marathe, Dale Niederhauser, Craig Ogilvie, Sarah Ryan

Sarah M. Ryan

In this paper we investigate the ways that students' problem-solving behaviors evolve when solving multi-faceted, context-rich problems within a structured, computer-based learning environment. During the semester, groups of two or three students worked on several problems that required drawing on more than one concept and, hence, could not be readily solved with simple "plug-and-chug" strategies. The problems were presented to students in a data-rich, online problem-solving environment that tracked which information items were selected by students as they attempted to solve the problem. The students also completed a variety of tasks, like entering an initial qualitative analysis into an online …


Demonstrating The Principles Of Aperture Synthesis With The Very Small Radio Telescope, Jonathan M. Marr, Karel Durkota, Francis P. Wilkin, Adam Pere, Alan E.E. Rogers, Vincent L. Fish, Gabriel Holodak, Martina B. Arndt Jan 2011

Demonstrating The Principles Of Aperture Synthesis With The Very Small Radio Telescope, Jonathan M. Marr, Karel Durkota, Francis P. Wilkin, Adam Pere, Alan E.E. Rogers, Vincent L. Fish, Gabriel Holodak, Martina B. Arndt

Physics Faculty Publications

We have developed a set of college-level, table-top labs for teaching the basics of radio interferometry and aperture synthesis. These labs are performed with the Very Small Radio Telescope (VSRT), an interferometer using satellite TV electronics as detectors and compact fluorescent light bulbs as microwave signal sources. The hands-on experience provided by the VSRT in these labs allows students to gain a conceptual understanding of radio interferometry and aperture synthesis without the rigorous mathematical background traditionally required.


Impulse-Momentum Diagrams, David Rosengrant Jan 2011

Impulse-Momentum Diagrams, David Rosengrant

Faculty and Research Publications

Multiple representations are a valuable tool to help students learn and understand physics concepts. Furthermore, representations help students learn how to think and act like real scientists. These representations include: pictures, free‐body diagrams, energy bar charts, electrical circuits, and, more recently, computer simulations and animations. However, instructors have limited choices when they want to help their students understand impulse and momentum. One of the only available options is the impulse‐momentum bar chart. The bar charts can effectively show the magnitude of the momentum as well as help students understand conservation of momentum, but they do not easily show the actual …


Scaffolding With Video Prior To Sophomore Physics Lab: The Addition And Resolution Of Vectors, David J. Sitar Jan 2011

Scaffolding With Video Prior To Sophomore Physics Lab: The Addition And Resolution Of Vectors, David J. Sitar

Master's Theses and Doctoral Dissertations

No abstract provided.


Identifying And Addressing Specific Student Difficulties In Advanced Thermal Physics, Trevor I. Smith Jan 2011

Identifying And Addressing Specific Student Difficulties In Advanced Thermal Physics, Trevor I. Smith

Electronic Theses and Dissertations

As part of an ongoing multi-university research study on student understanding of concepts in thermal physics at the upper division, I identified several student difficulties with topics related to heat engines (especially the Carnot cycle), as well as difficulties related to the Boltzmann factor. In an effort to address these difficulties, I developed two guided-inquiry worksheet activities (a.k.a. tutorials) for use in advanced undergraduate thermal physics courses. Both tutorials seek to improve student understanding of the utility and physical background of a particular mathematical expression. One tutorial focuses on a derivation of Carnot's theorem regarding the limit on thermodynamic efficiency, …