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2006

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Articles 5731 - 5760 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Introduction To N-Adaptive Fuzzy Models To Analyze Public Opinion On Aids, Florentin Smarandache, W.B. Vasantha Kandasamy Jan 2006

Introduction To N-Adaptive Fuzzy Models To Analyze Public Opinion On Aids, Florentin Smarandache, W.B. Vasantha Kandasamy

Branch Mathematics and Statistics Faculty and Staff Publications

“AIDS is not simply a physical malady, it is also an artifact of social and sexual transgression, violated taboo, fractured identity—political and personal projections. Its key words are primarily the property of the powerful. AIDS: Keywords – is my attempt to identify and contest some of the assumptions underlying our current ‘knowledge’. In this effort I am joined by many AIDS activists including people living with AIDS— Acquired Immuno Deficiency Syndrome. “A syndrome is a pattern of symptoms pointing to a “morbid state” which may or may not be caused by infectious agents; a disease, on the other hand is, …

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Dynamics Of An Atmospheric Pressure Plasma Plume Generated By Submicrosecond Voltage Pulses, Xinpei Lu, Mounir Laroussi Jan 2006

Dynamics Of An Atmospheric Pressure Plasma Plume Generated By Submicrosecond Voltage Pulses, Xinpei Lu, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

Nonequilibrium plasmas driven by submicrosecond high voltage pulses have been proven to produce high-energy electrons, which in turn lead to enhanced ionization and excitations. Here, we describe a device capable of launching a cold plasma plume in the surrounding air. This device, "the plasma pencil," is driven by few hundred nanosecond wide pulses at repetition rates of a few kilohertz. Correlation between current-voltage characteristics and fast photography shows that the plasma plume is in fact a small bulletlike volume of plasma traveling at unusually high velocities. A model based on photoionization is used to explain the propagation kinetics of the …

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The Formal Laplace-Borel Transform Of Fliess Operators And The Composition Product, Yaqin Li, W. Steven Gray Jan 2006

The Formal Laplace-Borel Transform Of Fliess Operators And The Composition Product, Yaqin Li, W. Steven Gray

Electrical & Computer Engineering Faculty Publications

The formal Laplace-Borel transform of an analytic integral operator, known as a Fliess operator, is defined and developed. Then, in conjunction with the composition product over formal power series, the formal Laplace-Borel transform is shown to provide an isomorphism between the semigroup of all Fliess operators under operator composition and the semigroup of all locally convergent formal power series under the composition product. Finally, the formal Laplace-Borel transform is applied in a systems theory setting to explicitly derive the relationship between the formal Laplace transform of the input and output functions of a Fliess operator. This gives a compact interpretation …

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Growth Of Ge Quantum Dots On Si(100)-(2×1) By Pulsed Laser Deposition, M. S. Hegazy, H. E. Elsayed-Ali Jan 2006

Growth Of Ge Quantum Dots On Si(100)-(2×1) By Pulsed Laser Deposition, M. S. Hegazy, H. E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Self-assembled germanium quantum dots (QDs) were grown on Si(100)-(2×1) by pulsed laser deposition. In situ reflection-high energy electron diffraction (RHEED) and postdeposition atomic force microscopy are used to study the growth of the QDs. Several films of different thicknesses were grown at a substrate temperature of 400 °C using a Q-switched Nd:yttrium aluminum garnet laser (λ= 1064 nm, 40 ns pulse width, 23 J/cm 2 fluence, and 10 Hz repetition rate). At low film thicknesses, hut clusters that are faceted by different planes, depending on their height, are observed after the completion of the wetting layer. With increasing film thickness, …

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Markov Switching And Jump Diffusion Models With Applications In Mathematical Finance, Shengkun Xie Jan 2006

Markov Switching And Jump Diffusion Models With Applications In Mathematical Finance, Shengkun Xie

Theses and Dissertations (Comprehensive)

In this thesis, we study some jump diffusion models with Markov switching and transition densities for Markov switching diffusion processes with and without an absorbing barrier. We work out some analytical results, which have useful applications in mathematical finance and other related fields. The first-passage time problem for a Markov switching model is also studied and European type options and lookback options are computed in closed-form as examples to show that these models can be applied in practice. We apply optimization methods and kernel smoothing techniques to produce some important numerical results that show that jump diffusion with Markov switching …

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An Analysis Of Community Forest Implementation In British Columbia, Canada, Ryan C. Bullock Jan 2006

An Analysis Of Community Forest Implementation In British Columbia, Canada, Ryan C. Bullock

Theses and Dissertations (Comprehensive)

The community forest is increasingly seen as an alternative to industrial forestry for its perceived potential to mitigate conflict in forest resource management and planning. Theoretically, a community-based approach affords the chance to assert local values, provide local benefits, and manage resources differently than established top-down approaches. Yet practical examples of community forest initiatives in Canada reveal a host of constraints. This research uses a multiple case study design to investigate the motivations for and challenges to implementing community forests in British Columbia, Canada. Observations are drawn from four case studies (Denman Island, Malcolm Island, Cortes Island, and Creston) in …

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Modeling Uncertainty In Mountain Pine Beetle Management Systems, Anthony L. Alfano Jan 2006

Modeling Uncertainty In Mountain Pine Beetle Management Systems, Anthony L. Alfano

Theses and Dissertations (Comprehensive)

This study attempts to introduce elements of data uncertainty into the Shore and Safranyik model for approximating risk and susceptibility ratings for Mountain Pine Beetle attack in the Morice Forest District of British Columbia, Canada. Data uncertainty is introduced into the modeling procedure by introducing attribute uncertainty and spatial (boundary) vagueness into representations of Forest Inventory Polygon data, an essential component of the Shore and Safranyik modeling system, for the purposes of assessing the effects of uncertainty on the results of the Shore and Safranyik susceptibility modeling procedure. Introducing uncertainty into the forest inventory data is done by introducing spatial …

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Interdependency Of Pharmacokinetic Parameters: A Chicken-And-Egg Problem? Not!, Reza Mehvar Jan 2006

Interdependency Of Pharmacokinetic Parameters: A Chicken-And-Egg Problem? Not!, Reza Mehvar

Pharmacy Faculty Articles and Research

Pharmacokinetic (PK) software packages are widely used by scientists in different disciplines to estimate PK parameters. However, their use without a clear understanding of physiological parameters affecting the PK parameters and how different PK parameters are related to each other may result in erroneous interpretation of data. Often, mathematical relationships used for the estimation of PK parameters obscure the true physiological relationships among these parameters, prompting a discussion of which parameter came first and giving the appearance of the-chicken-and-the-egg dilemma. In this article, the author attempts to show how different PK parameters are related to physiological parameters and each other …

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Patterns Of Total Suspended Solids Concentration And The Influence Of Antecedent Conditions On Hydrograph Response To Precipitation Events On Beaver Creek, Ontario, Matthew Peter Roy Mittler Jan 2006

Patterns Of Total Suspended Solids Concentration And The Influence Of Antecedent Conditions On Hydrograph Response To Precipitation Events On Beaver Creek, Ontario, Matthew Peter Roy Mittler

Theses and Dissertations (Comprehensive)

This study explored relationships between suspended solids concentration and discharge, the influence of antecedent conditions on event hydrograhs and the state of dynamic equilibrium in a second-order stream (Beaver Creek), draining an agricultural basin in southern Ontario, near the City of Waterloo. Beaver creek was monitored for nineteen weeks from July to November of 2005. Thirteen precipitation events of various magnitude and duration were examined within the study period. Discharge and total suspended soils were sampled throughout the events. Cross sectional profiles of six transects were measured prior to and after each event. Base flow, antecedent conditions and event response …

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An Investigation Into The Spatial And Temporal Movement Of The Sand Dunes In The West Lake Ecosystem Of Sandbanks Provincial Park And The Implications For Management (Ontario), Jayson A. Childs Jan 2006

An Investigation Into The Spatial And Temporal Movement Of The Sand Dunes In The West Lake Ecosystem Of Sandbanks Provincial Park And The Implications For Management (Ontario), Jayson A. Childs

Theses and Dissertations (Comprehensive)

Sandbanks Provincial Park is located on the northern shore of eastern Lake Ontario approximately 150km east of Toronto. The park is located on the southwestern shore of Prince Edward County in Hallowell Township and the research site was located on the larger of the two baymouth barriers the park protects. The research into aeolian sediment transport was carried out over twelve months in 2003--2004 on the Wellington Baymouth barrier. Vegetated sand dunes are sensitive geomorphic systems and when the protective cover is damaged and removed, changes are inevitable. The study examined variations in the amount of sediment transport in different …

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Implementing The Oak Ridges Moraine Conservation Plan: A Case Study Of Initial Implementation Experiences, Ryan Dore Jan 2006

Implementing The Oak Ridges Moraine Conservation Plan: A Case Study Of Initial Implementation Experiences, Ryan Dore

Theses and Dissertations (Comprehensive)

Implementing an ecologically-based land use plan presents a variety of challenges. To gain insight into these challenges, this study focuses on the experiences of actor intimately involved in implementing the Oak Ridges Moraine Conservation Plan. To begin, a conceptual overview of regional planning/growth management, ecosystem-based management, and policy implementation literature and concepts are presented, along with a contextual overview of the Oak Ridges Moraine Conservation Plan. Following the conceptual and contextual overviews, Hanna’s (2006) framework addressing eight obstacles to policy implementation is used to discuss and analyze the information collected during the interview process. Lastly, seven lessons for implementing an …

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Detecting Hot Spots Of Mountain Pine Beetle Infestations In The Forests Of British Columbia: An Approach Using Local Spatial Autocorrelation, Rodrigo Tapia-Mcclung Jan 2006

Detecting Hot Spots Of Mountain Pine Beetle Infestations In The Forests Of British Columbia: An Approach Using Local Spatial Autocorrelation, Rodrigo Tapia-Mcclung

Theses and Dissertations (Comprehensive)

Mountain pine beetle (Dendroctonus ponderosae Hopkins) is an endemic species in the forests of British Columbia that has become epidemic and reached infestation levels like never before. Different approaches have been taken in order to try and manage the forest and understand the processes affecting the behavior of mountain pine beetle. No single model has been entirely successful in unearthing the complexity of mountain pine beetle behavior. In this thesis, large spatial data sets of mountain pine beetle attacks, obtained from helicopter and ground surveys, and further adjusted for the incorporation of uncertainty, are studied using a spatial autocorrelation approach …

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Assessment And Classification Of A Modified Urban Stream: Schneider Creek, Kitchener, Ontario, J. Andrew Carnegie Jan 2006

Assessment And Classification Of A Modified Urban Stream: Schneider Creek, Kitchener, Ontario, J. Andrew Carnegie

Theses and Dissertations (Comprehensive)

This study has produced an assessment framework and classification designed specifically for urban modified streams. While many stream assessment frameworks do exist, most are designed for natural streams and as such have no provision for characteristics of urban streams such as concrete channelization, storm drains, and urban debris. Building upon previous assessment and classification schemes, both urban and natural, this framework satisfies this need. It strengths lie in its user-friendly, visual-based approach to assessment by employing representative photographs and qualitative information to aid the user. A total of ten variables were employed that are scaled on a spectrum of categories, …

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Seasonal Variability Of Carbon Dioxide Fluxes Over A Heterogeneous Low Tundra Ecosystem, Ronald P. Van Haarlem Jan 2006

Seasonal Variability Of Carbon Dioxide Fluxes Over A Heterogeneous Low Tundra Ecosystem, Ronald P. Van Haarlem

Theses and Dissertations (Comprehensive)

The seasonal carbon dioxide (CO2) budget and its associated environmental controlling parameters, soil moisture, soil temperature and depth to frost were investigated throughout the growing period during the summer of 2004. The study site is located within the low arctic tundra environment at Daring Lake, NWT (62⁰52’N, 111⁰35’W). The CO2 fluxes from an area of heterogeneous tundra composition were intensely monitored. The net seasonal CO2 budget was approximated to be 10.2 g C-CO2 m-2 for 100 days (DOY 159-259) of the 2004 snow-free study period. The CO2 flux dynamic was found to differ between 4 identified seasonal periods—melt, pre-green, green …

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Of Fish And People: Managerial Ecology In Newfoundland And Labrador Cod Fisheries, Dean Louis Yelwa Bavington Jan 2006

Of Fish And People: Managerial Ecology In Newfoundland And Labrador Cod Fisheries, Dean Louis Yelwa Bavington

Theses and Dissertations (Comprehensive)

This dissertation aims to understand the history of, and possible alternatives to, managerial responses to socio-ecological issues by examining one of the largest natural resource management failures of the twentieth century—the collapse of the Northern cod fisheries off Newfoundland and Labrador, Canada. In 1992, the Northern cod fishery off Newfoundland and Labrador (the world's largest ground fishery) was shut down. The Northern cod had been reduced to 1% of their historic spawning biomass and cod fishing as a way of life had come to an end after a 500 year history. The dissertation develops and applies a critical theory of …

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Water Quality Issues In The Illinois River Watershed: A Proposal For New Voluntary Incentives, Tory B. Hodges, Jennie S. Popp Jan 2006

Water Quality Issues In The Illinois River Watershed: A Proposal For New Voluntary Incentives, Tory B. Hodges, Jennie S. Popp

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Concerns about water quality degradation exist in Northwest Arkansas. The purpose of this study was to analyze the potential usefulness of U.S. conservation programs in addressing water quality concerns on farms in the Illinois River watershed as well as greater Washington County, Arkansas. It was hypothesized that neither the Environmental Quality Incentives Program (EQIP) nor the Conservation Security Program (CSP) in their current forms effectively assists farmers in meeting water-quality management goals. That hypothesis was tested by 1) examining agricultural characteristics of the watershed, 2) actual adoption of EQIP and CSP in Washington County and Arkansas, and, 3) identifying factors …

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The Challenges Of Itil Implementations, Jason Gray Jan 2006

The Challenges Of Itil Implementations, Jason Gray

Theses : Honours

Originating from the UK, the IT Infrastructure Library (ITIL) is an IT Service Management framework whose adoption is rapidly spreading throughout Canada, Netherlands, South Africa, India, USA, and Australia. Promoted as a collection of "Best Practices" in IT service management, ITIL is gaining a reputation as a "silver bullet" to IT Service Management woes and is now .gaining popularity amongst IT vendors and leaders of best practices worldwide. Increased IT productivity, IT accountability, increased compliance and reduced IT costs, are just some of the promised list of benefits. More and more organisations are plam1ing to embark on ITIL implementations as …

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Radio Frequency Enabled Soil Redox Potential Sensor Networks, Chris Holme Jan 2006

Radio Frequency Enabled Soil Redox Potential Sensor Networks, Chris Holme

Theses : Honours

There is a need for' cost effective tools and data collection methods for field measurements; to increase both productivity and volumes of collected data in the quest for enhanced understanding and management of environmental systems. To such end, various technologies that may be combined into a cost effective soil redox sensor network were explored. Suitability of each technology, as a component of said network was evaluated. A prototype soil redox sensor network was constructed and basic laboratory and field testing was completed. Results indicate that the prototype sensor network functions correctly within bounds. Both laboratory and field testing show that …

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The Determination Of Probes For The Indirect Detection Of Anions In Capillary Zone Electrophoresis Using Light Emitting Diode Detection, Peter Ashley Balding Jan 2006

The Determination Of Probes For The Indirect Detection Of Anions In Capillary Zone Electrophoresis Using Light Emitting Diode Detection, Peter Ashley Balding

Theses : Honours

This study investigated the potential of a number of compounds to act as probes for the indirect detection of inorganic and organic anions separated by capillary zone electrophoresis and using light emitting diodes (LED) as the light source. Desirable characteristics of the probe anion included: high molar absorptivity, moderate to high electrophoretic mobility, and having a wavelength of maximum absorbance near the maximum emission wavelength of a LED. A preliminary study led to the evaluation of eleven possible compounds. Two of these, p-nitrophenol and 4-hydroxy-3,5-dinitrobenzoic acid were selected for further study as they fulfilled the criteria previously mentioned. The optimised …

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An Attitude And Perception Study Of Wireless Network Usage In Home Environments, Patryk Szewczyk Jan 2006

An Attitude And Perception Study Of Wireless Network Usage In Home Environments, Patryk Szewczyk

Theses : Honours

Research on the use of 802.11 wireless networking and wireless security has in the past focused predominantly on corporations who generally have access to resources specifically allocated to computer and network security. Research has also focused on identifying the flaws in wireless network security, and developing stronger and safer methods which may be incorporated. To date there has been a lack of research into determining what the individual at home perceives towards wireless security. As broadband Internet connections are now predominantly chosen, the amount of available bandwidth open to exploitation is significantly higher than the now becoming obsolete dialup connection. …

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Use Of A Weighted Matching Algorithm To Sequence Clusters In Spatial Join Processing, Husen Husen Jan 2006

Use Of A Weighted Matching Algorithm To Sequence Clusters In Spatial Join Processing, Husen Husen

Theses : Honours

One of the most expensive operations in a spatial database is spatial join processing. This study focuses on how to improve the performance of such processing. The main objective is to reduce the Input/Output (I/O) cost of the spatial join process by using a technique called cluster-scheduling. Generally, the spatial join is processed in two steps, namely filtering and refinement. The cluster-scheduling technique is performed after the filtering step and before the refinement step and is part of the housekeeping phase. The key point of this technique is to realise order wherein two consecutive clusters in the sequence have maximal …

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The Kronecker Product, Bobbi Jo Broxson Jan 2006

The Kronecker Product, Bobbi Jo Broxson

UNF Graduate Theses and Dissertations

This paper presents a detailed discussion of the Kronecker product of matrices. It begins with the definition and some basic properties of the Kronecker product. Statements will be proven that reveal information concerning the eigenvalues, singular values, rank, trace, and determinant of the Kronecker product of two matrices. The Kronecker product will then be employed to solve linear matrix equations. An investigation of the commutativity of the Kronecker product will be carried out using permutation matrices. The Jordan - Canonical form of a Kronecker product will be examined. Variations such as the Kronecker sum and generalized Kronecker product will be …

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Improving Data Access For Computational Grid Applications, Ron Oldfield, David Kotz Jan 2006

Improving Data Access For Computational Grid Applications, Ron Oldfield, David Kotz

Dartmouth Scholarship

High-performance computing increasingly occurs on “computational grids” composed of heterogeneous and geographically distributed systems of computers, networks, and storage devices that collectively act as a single “virtual” computer. A key challenge in this environment is to provide efficient access to data distributed across remote data servers. Our parallel I/O framework, called Armada, allows application and data-set providers to flexibly compose graphs of processing modules that describe the distribution, application interfaces, and processing required of the dataset before computation. Although the framework provides a simple programming model for the application programmer and the data-set provider, the resulting graph may contain bottlenecks …

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Thermal Variations In The Hyporheic Zone Of A Karst Stream, Toby Dogwiler, Carol Wicks Jan 2006

Thermal Variations In The Hyporheic Zone Of A Karst Stream, Toby Dogwiler, Carol Wicks

International Journal of Speleology

This investigation quantifies how temperatures in the streambed sediments of a karst stream fluctuate in relation to discharge, seasonal, and diurnal temperature variations as the stream passes through a karst window. Furthermore, the linkages between meteorological processes and temperature variation in the hyporheic zone are delineated. Examination of a high-resolution, three dimensional record of temperature variation in a karst stream substrate provides insight into thermal disturbances in the hyporheic zone. Temperatures in the upper portion of the hyporheic zone are strongly linked to air temperatures via the surface water. The variation is considerably less as depth increases. The annual temperature …

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Caves And Speleogenesis At Blomstrandsøya, Kongsfjord, W. Spitsbergen, Stein-Erik Lauritzen Jan 2006

Caves And Speleogenesis At Blomstrandsøya, Kongsfjord, W. Spitsbergen, Stein-Erik Lauritzen

International Journal of Speleology

Blomstrandsøya, at Kongsfjord (78° 57’N), Spitsbergen, is within the high arctic, a completely permafrozen zone. The bedrock consists of Paleozoic marbles and has yielded a surprising amount of karst features. Early phases of hydrothermal, possibly Caledonian, speleogenesis and subsequent Devonian karstification with redbed deposits is well documented. 62 active seacaves, and more than 30 relict karst caves were found in the coastal cliffs and in escarpment faces around the island. All caves have very limited extent; they are either quite short, like most of the active sea caves, or they are soon choked by frozen sediments and ground ice after …

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Salt Ingestion Caves, Charles A. Lundquist, William W. Varnedoe Jr. Jan 2006

Salt Ingestion Caves, Charles A. Lundquist, William W. Varnedoe Jr.

International Journal of Speleology

Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, over generations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a unique class of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. An example in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer or bison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been …

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Vashegyite From Gaura Cu Muscă Cave (Locvei Mountains, Romania): A New And Rare Phosphate Occurrence, Bogdan P. Onac, Luminiţa Zaharia, Joe Kearns, Daniel Veres Jan 2006

Vashegyite From Gaura Cu Muscă Cave (Locvei Mountains, Romania): A New And Rare Phosphate Occurrence, Bogdan P. Onac, Luminiţa Zaharia, Joe Kearns, Daniel Veres

International Journal of Speleology

This study investigated the occurrence of vashegyite from a guano-rich deposit located in the Gaura cu Muscă Cave, Romania. Analytical methods used include optical microscopy, X-ray powder diffraction (XRD), scanning electron-microscopy (SEM), inductively coupled plasma-atomic emission spectrometry (ICP-AES), thermal investigations and Fourier-transform infrared (FT-IR) analyses. Vashegyite occurs as friable, chalky white, irregular nodules of up to 2.5 cm in diameter, within a 15 cm thick sequence of organic and minerogenic sediments. The chemical structural formula is: (Al10.91Fe3+0.06Na0.1Ca0.02Mg0.08)Σ=11.17[(PO4)8.78(SiO4)0.056]Σ=8.83(OH) …

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Relationships Between Deflector Faults, Collapse Dolines And Collector Channel Formation: Some Examples From Slovenia, France Šušteršič Jan 2006

Relationships Between Deflector Faults, Collapse Dolines And Collector Channel Formation: Some Examples From Slovenia, France Šušteršič

International Journal of Speleology

In some Slovenian caves collector channels gather sinking underground streams and redirect them for potentially long distances parallel to certain faults. The collector channels formed due to ongoing long-term collapse of cave roofs at the points where passages break through the faults, which function as a kind of screen and are termed deflector faults. The fault trends are marked by collapse within the caves, and by active collapse dolines at the surface.

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Tracer-Test Design For Losing Stream–Aquifer Systems, Malcolm S. Field Jan 2006

Tracer-Test Design For Losing Stream–Aquifer Systems, Malcolm S. Field

International Journal of Speleology

Hydrological tracer testing is an effective way for assessing the significance and extent of leakage through the bed of an influent (losing and sinking) stream. In karstic terranes, leakage from losing and sinking streams typically resurge at downstream springs, but flow may be intercepted by production wells. Although sinking streams that disappear into swallow holes and caves are relatively easy to trace, developing a tracer test design for a losing stream that allows slow percolation through its bed is complicated by the lack of basic knowledge regarding leakage rate, leakage locations along its length, and temporal variability. To overcome these …

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Radon In Caves: Clinical Aspects, Stephen A. Craven, Berend J. Smit Jan 2006

Radon In Caves: Clinical Aspects, Stephen A. Craven, Berend J. Smit

International Journal of Speleology

Historical, experimental and clinical evidence is presented to suggest that radon constitutes a relatively small carcinogenic risk for casual visitors to caves. The risk is dependent on radon levels and the smoking of tobacco. Show cave guides, chronically exposed to radon, may be at increased risk for lung cancer due to the effects of radon, especially if they are smokers of tobacco.

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