Digital Commons Network^™

Petrographic And Geochemical Study On Cave Pearls From Kanaan Cave (Lebanon), Fadi H. Nader

International Journal of Speleology

The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon). The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian) which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy) and geochemical analyses (major/trace elements and stable isotopes). The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show δ¹⁸O_V-PDB values of …

Seasonal Variations Of Co2 And 222Rn In A Mediterranean Sinkhole - Spring (Causse D’Aumelas, Se France), Christelle Batiot-Guilhe, Jean-Luc Seidel, Hervé Jourde, Olivier Hébrard, Vincent Bailly-Comte

International Journal of Speleology

Carbon dioxide and ²²²Rn monitoring of the atmosphere of a Mediterranean sink hole - spring (SE France) during two hydrological cycles (from September 2004 to September 2006) showed seasonal variations with very high concentrations during summer (greater than 6% and 20 000 Bq/m³, respectively). Gas dynamics in caves often show seasonal variations. Meteorological parameters (barometric pressure and temperature mainly), cave geometry and fracture networks control exchanges between the cavity and outside atmosphere. Carbon dioxide and ²²²Rn may have different sources (atmosphere, soil, bedrock, deep gas diffusion, in situ oxidation of organic matter and, in some caves, …

Eogenetic Karst, Glacioeustatic Cave Pools And Anchialine Environments On Mallorca Island: A Discussion Of Coastal Speleogenesis, Angel Ginés, Joaquín Ginés

International Journal of Speleology

Coastal karst is characterized by special geomorphologic and hydrodynamic conditions as well as by peculiar sedimentary, geochemical, and biospeleological environments. Generally, the more distinctive karstic features produced near the coastline are strongly influenced by sea-level changes, which generate a broad set of interactions between littoral processes and karst development. The glacioeustatic rises and falls of sea level affected the littoral karst in different ways, namely: vertical and horizontal shifts in the shoreline position, changes in elevation of the local water table, and vertical displacements of the halocline. Most eogenetic karsts have been subjected over long time spans to repeated changes …

Sails: A New Gypsum Speleothem From Naica, Chihuahua, Mexico, Tullio Bernabei, Paolo Forti, Roberto Villasuso

International Journal of Speleology

The caves of Naica (Chihuahua, Mexico) are perhaps the most famous mine caves of the world due to the presence of gigantic gypsum crystals. Nevertheless, very little research has been carried out on this karst area until now. A multidisciplinary investigation started in 2006 with the aim not only to define the genesis and the age of the Naica gypsum crystals, but also on other scientific aspects of these caves. This paper describes a completely new type of gypsum speleothem: the “sails”, observed only inside the Cueva de las Velas, one of the caves of the Naica system. This speleothem …

Acadian Biospeleology: Composition And Ecology Of Cave Fauna Of Nova Scotia And Southern New Brunswick, Canada, Max Moseley

International Journal of Speleology

The vertebrate and invertebrate fauna, environment and habitats of caves and disused mines in Nova Scotia and southern New Brunswick are provisionally catalogued and described, based on field collections made over many years. The area was glaciated and the subterranean fauna consists of non-troglobites all of which have arrived and colonised the caves during or following final recession of the Pleistocene glaciers. The statistical composition of the fauna at the higher taxonomic level is similar to that in Ontario, but is less species rich and there are some notable ecological and other differences. Porcupine dung accumulations are an important habitat …

Bomb-Spike Dating Of A Mummified Baboon In Ludwig Cave, Namibia, Greg Hodgins, George A. Brook, Eugene Marais

International Journal of Speleology

In 1982 a mummified adult female baboon was discovered on a ledge in Ludwig Cave in Namibia. A toe bone was removed for dating in July 1995. AMS radiocarbon dating of bone collagen, tendon, and skin indicates a post-modern age. Application of the atomic bomb-spike calibration curve suggests death in late 1977 and an age at death of around 19 years. Baboons roost in the cave and the mummified female, along with a mummified juvenile male discovered in 2002 and three rotting corpses discovered in 1995, were probably chased by other baboons or by leopards down a ca. 6 m …

Diffusion And Fractional Diffusion Based Models For Multiple Light Scattering And Image Analysis, Jonathan Blackledge

Articles

This paper considers a fractional light diffusion model as an approach to characterizing the case when intermediate scattering processes are present, i.e. the scattering regime is neither strong nor weak. In order to introduce the basis for this approach, we revisit the elements of formal scattering theory and the classical diffusion problem in terms of solutions to the inhomogeneous wave and diffusion equations respectively. We then address the significance of these equations in terms of a random walk model for multiple scattering. This leads to the proposition of a fractional diffusion equation for modelling intermediate strength scattering that is based …

An Approach To Unification Using A Linear Systems Model For The Propagation Of Broad-Band Signals, Jonathan Blackledge

Articles

We review the inhomogeneous scalar Helmholtz equation in three-dimensions and the scattering of scalar wavefields from a scatterer of compact support. An asymptotic solution is then considered representing the effect of the frequency approaching zero when a ‘wavefield’ reduces to a ‘field’. The characteristics of ultra-low frequency Helmholtz scattering are then considered and the physical significance discussed of a model that is based on the scattering of Helmholtz wavefields over a broad frequency spectrum. This is equivalent to using a linear systems approach for modelling the propagation, interaction and detection of broad-band signals and provides an approach to the classification …

Digital Watermarking And Self-Authentication Using Chirp Coding, Jonathan Blackledge

Articles

This paper discusses a new approach to ‘watermarking’ digital signals using linear frequency modulated or ‘chirp’ coding. The principles underlying this approach are based on the use of a matched filter to provide a reconstruction of a chirped code that is uniquely robust, i.e. in the case of very low signal-to-noise ratios.

Chirp coding for authenticating data is generic in the sense that it can be used for a range of data types and applications (the authentication of speech and audio signals, for example). The theoretical and computational aspects of the matched filter and the properties of a chirp are …

Experimental Study For The Conditions Of Analog Switching In Ferroelectric Liquid Crystal Cells, V. Manjuladevi, Yuri Panarin, J.K. Vij

Articles

The authors study the effect of the spontaneous polarization (PS) of a ferroelectric liquid crystal mixture with compensated helix and of the thickness of the alignment layer (da) on the analog switching in a cell. The quality of analog switching is established in terms of its contrast ratio, texture in the dark state, and the electrostatic energy. The latter approximates to PS 2da for da

Influence Of Electric Field And Light On An Easy Axis Of Nlc Confined By Rectangular Channel At Weak Surface Anchoring, S.V. Pasechnik, A.V. Dubtsov, Yuri Panarin, D.V. Shmeliova, V.A. Tsvetkov, V.G. Chigrinov

Articles

We present new experimental results on combined action of light and electric field on a nematic liquid crystal in a rectangular channel at a weak surface anchoring. The first experimental study of slow surface dynamics at combined action of electric field and polarized light in new experimental geometry was performed. Influence of polarized light on spatial twist-like deformation of a director field induced by electric field was established.

Discontinuous Change In The Smectic Layer Thickness In Ferrielectric Liquid Crystals, V. P. Panov, J. K. Vij, Yuri Panarin, C. Blanc, V. Lorman, J. W. Goodby

Articles

The temperature dependence of the thickness of thick free-standing films is studied using a high-resolution film thickness measurement technique. A small discontinuity in the temperature dependence of the smectic layer thickness at every phase transition between ferro-, ferri-, and antiferroelectric phases is observed. We show that the major contribution to it arises from a change in the smectic tilt angle.

Pure Non-Blocking Lc Based Matrix Optical Switch For All-Optical Fibre Networks, Yuri Panarin, V. Alex

Articles

New pure non-blocking matrix optical switch scheme for fiber networks is presented. The optical switch is based on conventional LCD technology, where the each pixel controls the polarization state of the light beam. The suggested switch offers several advantages over the conventional cross-point architecture such as: cost; complexity; size; adjustment; and optical performance

Optical Performance Of Non-Blocking 4x4 Optical Switch: Simulation And Experiment, V. Alex, A. Dubtsov, Yuri Panarin, T. Wilkinson

Articles

A prototype of pure non-blocking 4x4 optical LC switch was designed and built. This switch is based on conventional LCD technology, where the each pixel controlled the polarization state of the light beam. An addressing algorithm was described. The optical performance of the switch, such as cross-talk and insertion loss, was simulated and experimentally studied. The suggested approach offers several advantages over the conventional cross-point architecture such as: cost; complexity; size; adjustment; and optical performance.

Increasing Effectiveness Of Public Private Partnerships In The Irish Construction Industry, Louis Gunnigan

Doctoral

By 2003 the first Irish Public Private Partnership (PPP) projects had reached the operational stage. Media reports were emerging of significant differences in the effectiveness of these projects.

This research set out to find a means by which effectiveness of PPPs could be increased and to develop a model that would assist PPP practitioners with this task in the future. Through a literature review, the Irish PPP process was mapped, the changes encountered in the introduction of PPP were investigated and a conceptual model – based on a traditional process model - was proposed. The model was tested by examining …

Modelling And Computer Simulation Of Radar Screening Using Plasma Clouds, Jonathan Blackledge

Articles

Following a brief introduction on the principles of screening an aerospace vehicle using a plasma, we develop models for the Impulse Response Functions (IRFs) associated with microwave (Radar) back-scattering from a strong and weakly ionized plasma screen. In the latter case, it is shown that the strength of the return signal is determined by an IRF that is characterised by the simple negative exponential exp(−σ₀t/Є₀) where σ₀ is the average conductivity of the plasma, Є₀ is the permittivity of free space and t is the two-way travel time. For a weakly ionized plasma, the …

Realising Electronic Tendering In The Irish Construction Industry, Alan V. Hore

Conference papers

No abstract provided.

Efficiency Gains To Be Won Through The Introduction Of Electronic Tendering In The Construction Industry, Alan V. Hore, Roger West

Conference papers

The tendering process predominantly adopted in the Irish construction industry is largely paper-dependent. However, the increase in the availability of high speed Information Communications Technology (ICT) has meant that construction consultants can disseminate this information more cost effectively in an electronic format. The aim of this paper is to present a status report on an industry-led network project currently being undertaken by the Construction Information Technology Alliance (CITA) in Ireland. This project aims to demonstrate how greater effectiveness and efficiency can be applied to the tendering process by the application of ICT already used widely in other industries. The status …

Colour Doppler Spatial Resolution Performance Testing, Jacinta Browne, Ian Brown, Peter Hoskins, Amanda Watson, Alex Elliott

Articles

No abstract available

Phenomenographic Study Of Students’ Problem Solving Approaches In Physics, Laura Walsh, Robert Howard, Brian Bowe

Articles

This paper describes ongoing research investigating student approaches to quantitative and qualitative problem solving in physics. This empirical study was conducted using a phenomenographic approach to analyze data from individual semistructured problem solving interviews with 22 introductory college physics students. The main result of the study is a hierarchical set of categories that describe the students’ problem solving approaches in the context of introductory physics.

The Council Of Europe Addresses Cia Rendition And Detention Program, Monica Hakimi

Faculty Scholarship

In November 2005, the U.S. media reported that the Central Intelligence Agency was operating secret detention facilities in a handful of foreign countries, including two in eastern Europe, and that detainees were often transferred between those facilities and states known to engage in torture. The news that terrorism suspects may have been denied their human rights in member states of the Council of Europe caused concern within the Council and triggered several responses. Within days of the media reports, the Council's Parliamentary Assembly appointed a rapporteur to investigate the extent to which member states were participating in the CIA program. …

The Future Of International Law: Members' Reception And Plenary Panel, Georgetown University Law Center – Remarks By Lori Damrosch, Lori Fisler Damrosch

Faculty Scholarship

It is a privilege to follow Judge Owada and to take up the challenge offered by the theme statement of this panel: to assess trends that we perceive to be shifting the future of international law, while also interrogating claims of their newness. Perhaps everything that we think of as new has some resonance with the past.

Ensuring Effective Representation Of Parents In Dependency And Neglect Cases, Clare Huntington

Faculty Scholarship

Since 2005, the Colorado Supreme Court Respondent Parents' Counsel Task Force has been working to ensure the effective representation of parents in dependency and neglect proceedings. This article describes the work of the Task Force.

Panel One: Lessons Learned: Gender Analyses Of Past Policies And Practices: Introduction, Suzanne B. Goldberg

Faculty Scholarship

Hello. I'm Suzanne Goldberg. I am pleased to welcome you to the first of two afternoon panels as part of the Women's Rights Law Reporter Symposium, "Lessons Learned: Gender Analyses of Past Policies and Practices." Thank you to Dr. Enarson for the wonderful opening to our conversation today. She has inspired us to think about broadening our analytic lens by foregrounding questions of gender in our consideration of disasters and disaster relief.

Book Review: Conquest In Cyberspace: National Security And Information Warfare, Gary C. Kessler

Publications

This document is Dr. Kessler's review of Conquest in Cyberspace: National Security and Information Warfare, by Martin C. Libicki. Cambridge University Press, 2007. ISBN 978-0-521-69214-4

Asthme Au Travail : Plomberie Et Chauffage : Fiche De Prévention, Brigitte Roberge, Éric Audet, Denyse Gautrin

Fiches

No abstract provided.

Asthme Au Travail : Information Et Prévention : Fiche De Prévention, Denyse Gautrin, Sylvie Daigle, Nicole Goyer

Fiches

No abstract provided.

How Does "Equal Liberty" Fare In Relation To Other Approaches To The Religion Clauses?, Kent Greenawalt

Faculty Scholarship

As one of four contributors to an issue celebrating Christopher Eisgruber and Lawrence Sager's Religious Freedom and the Constitution, I have chosen to write an Essay that differs from an ordinary review. I compare the authors' approach with two other recent formulations of what should be central for the jurisprudence of the Religion Clauses. Since I have recently published my own treatment of the Free Exercise Clause, and a second volume on the Establishment Clause is in the pipeline toward publication, I do not here present my own positive views (though I provide references for interested readers). Those views …

Economic Policy In The Public Interest, Jagdish N. Bhagwati

Faculty Scholarship

Economists, whose discipline has always had a strong relationship to moral philosophy (Adam Smith, the author of The Wealth of Nations, also wrote the celebrated Theory of Moral Sentiments), have always seen their role in society as that of pursuing the public good. They properly see themselves as guardians of the public interest, and to be engaged in public-policy debates against special interests who wish to ‘capture’ policy to advance their narrowly circumscribed, self-serving agendas.

The Social Costs Of Property Rights In Broadcast (And Cable) Signals, Shyamkrishna Balganesh

Faculty Scholarship

The use of property as a regulatory mechanism in the telecommunications sector is hardly novel. Since the early twentieth century, policy makers and regulators in the United States have experimented with different mechanisms for allocating private rights in the radio spectrum. In 1959, Ronald Coase proposed that the FCC auction rights in the broadcast spectrum and convert broadcast licenses into tradable commodities. However, it was not until very recently that the FCC implemented Coase's idea. At least part of the reason for the long delay in implementing this seemingly efficient mechanism lay in the public nature of broadcasting and the …