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The Role Of The Epikarst In Karst And Cave Hydrogeology: A Review, Paul W. Williams

International Journal of Speleology

The epikarst (also known as the subcutaneous zone) comprises highly weathered carbonate bedrock immediately beneath the surface or beneath the soil (when present) or exposed at the surface. Porosity and permeability are higher near the surface than at depth, consequently after recharge percolating rainwater is detained near the base of the epikarst, the detention ponding producing an epikarstic aquifer. Such an aquifer is found only where the uppermost part of the vadose zone is very weathered compared to the bedrock at depth. Sometimes this contrast in porosity and permeability does not occur either because the epikarst has been scraped off …

Some Applications Of Geochemical And Isotopic Techniques To Hydrogeology Of The Caves After Research In Two Sites (Nerja Cave-S Spain And Fourbanne System-French Jura), Jacques Mudry, Bartolomé Andreo, Arnaud Charmoille, Cristina Liñán, Francisco Carrasco

International Journal of Speleology

Caves constitute privileged sampling spots to investigate the hydrochemical behaviour of infiltration, but the representative nature of samples can limit their reach. Taking this into account many results can be obtained from chemistry of water sampled in the caves. Carbonate tracers enable to reconstruct the ‘history’ of drip water water, including rainfall and temperatures. Moreover, permanent drip waters prove durability of water stored in the unsaturated zone over the cave, and lags between rain inputs and drip output enable to evaluate transit time through the unsaturated zone. The comparison of input/output concentrations can also contribute to estimate the local water …

The Origin Of The Bemaraha Tsingy (Madagascar), Márton Veress, Dénes Lóczy, Zoltán Zentai, Gábor Tóth, Roland Schläffer

International Journal of Speleology

On Madagascar the most representative occurrences of tsingy are at Ankarana and Bemaraha. The tsingy are built up of giant grikes developed along cracks as well as karren features of much smaller size which cover the surfaces between grikes. We investigated the Bemaraha tsingy of Madagascar (surveyed profiles, measured grike directions, etc.) in order to reconstruct their development. The observations indicate that the majority of grikes of the tsingy are created from caves formed under the karst water table and subsequently opened up to the surface. The predominant processes may have been downward progressing dissolution or the collapse of cave …

Design And Optimization Of Abrasive Slurry Feed System, Control Circuit And Jet Drilling Tool For Mining Applications,, Pradeep Nambiath

Doctoral Dissertations

"This dissertation focused on an investigation of small diameter hole drilling using abrasive slurry jet (ASJ) technology. The existing ASJ feed systems were reviewed and found inadequate to satisfy the requirements of an ASJ drill. A novel feed system was designed which improved on existing systems by resolving problems with the inability to perform stop/start operations and ensure precise metering of abrasive feed. This system met standards of consistency and evenness of feed required for machining aircraft component parts for Air Force Research Laboratory (AFRL). Theoretical and experimental analysis of the power of an ASJ stream yielded valuable design information …

Formation And Removal Of Pesticides And Pesticide Transformation Products During Water Treatment, Evelyn F. Chamberlain

Doctoral Dissertations

"A comprehensive suite of over 60 pesticides (herbicides, insecticides, and fungicides) representing a variety of classes at environmentally relevant concentrations (low µg/L) were screened for reactivity under typical drinking water conditions and dosages. The most common oxidants/transformation agents in water treatment systems were examined for reactivity including free and combined chlorine, chlorine dioxide, permanganate, ozone, hydrogen peroxide, ultraviolet radiation, and high pH (alkaline hydrolysis). Due to the broad nature of the study, pesticide compounds were analyzed as multiple mixes broken into two groups based on analytical methods, those analyzed by GC/ECD and those by LC/MS. Combinations of reactive disinfectant/oxidant and …

Mechanics Of Dump Truck Vibrations In High-Impact Shovel Loading Operations, Nassib Aouad

Doctoral Dissertations

"The deployment of large machinery for low cost, bulk surface mine production operations has resulted in high-impact shovel loading operations (HISLO). In extreme cases, shovels load large dump trucks with 100-ton (or more) passes generating high-impact forces under gravity. HISLO generates high-frequency shockwaves that cause severe truck vibrations exposing operators to whole body vibrations (WBV). This WBV levels may exceed the recommended International Standards Organization (ISO) limits resulting in longterm lower-back disorders and other health problems. There is a need for fundamental and applied research to determine HISLO vibration levels for heavy mining machinery, their comparisons to ISO 2631 limits …

Beyond Intention, Kimberly Kessler Ferzan

Cardozo Law Review

No abstract provided.

The Suburb As A Legal Concept: The Problem Of Organization And The Fate Of Municipalities In American Law, Kenneth A. Stahl

Cardozo Law Review

No abstract provided.

Enabling Wind Turbine Generators To Participate In Power Grid Frequency Regulation For Enhanced Stability, Hongtao Ma

Doctoral Dissertations

"This dissertation focuses on wind farm frequency regulation capability to maintain the grid frequency stability. Wind plant power controllers are designed and tested for participation in grid frequency restoration. The small signal stability on sub-optimal operating points is analyzed and a de-loaded operating point is proposed.

In the first paper, a new frequency regulation scheme is developed for the wind turbine/generator/converter trio that will provide the capability to participate in restoring frequency in a way similar to the droop response of conventional generators. Output active power adjustment can be realized by both converter and pitch angle control in addition to …

Friction Stir Channeling: An Innovative Technique For Heat Exchanger Manufacturing, Nagarajan Balasubramanian

Doctoral Dissertations

"Friction stir processing (FSP) is an emerging processing technique based on the principles of friction stir welding (FSW), which is a relatively new solid-state metal joining process developed by The Welding Institute, UK. Some of the unique features of FSW such as the low amount of heat generated, extensive plastic deformation and controlled flow of material is being exploited to develop new material modification and manufacturing processes. Friction stir channeling (FSC) is one such adaptation of FSP that can produce continuous and stable internal channels for application in heat exchanging equipment. Friction stir channeling produces these channels if the defect …

Inverse Limits Of Permutation Maps, Robbie A. Beane

Doctoral Dissertations

"In this paper we study the topological properties of continua which arise as inverse limits on [0; 1] with bonding maps chosen from the permutation family of Markov maps. For such inverse limits, we examine the occurrence of indecomposability, the number of end points in the continuum, and the types of subcontinua present in the continuum. We provide a process for determining the topological structure of the inverse limit generated by a single permutation map, or by the composition of several such maps. Additionally, we show that all such inverse limits are Kelley continua. We will apply these results to …

Addressing Nonlinear Combustion Instabilities In Highly Dilute Spark Ignition Engine Operation, Brian C. Kaul

Doctoral Dissertations

"Dilute operation is a promising approach for increasing spark-ignition engine efficiency, in the form of either lean burn (air dilution) or EGR (inert dilution). High levels of charge dilution, however, lead to cyclic variability that is largely deterministic in nature. The determinism and nonlinear nature of the system indicate that it should be possible to reduce the cycle-to-cycle variations by implementing an electronic controller. Several needs arise when considering the development of such a controller. Three topics of interest are covered herein. First, a method of analysis for nonlinear dynamical systems is applied to engine data in order to estimate …

Universal Electric And Magnetic Fields Analyzer System, Yong Cheh Ho

Masters Theses

"Near-field probing is often used to measure the electric and magnetic fields above a printed circuit board (PCB) or integrated circuits (IC) chip in order to identify the sources and coupling paths of an electromagnetic interference (EMI) problem.

A wideband universal field analyzer was designed, built and tested in this thesis. The system is able to provide fast field scanning over a wide frequency range in lieu of its capabilities to measure multiple field components using a single probe design. Central to the system operation is the phase-shifting concept that provides wideband and wide- range phase-shifting.

The complete universal field …

Obscurant Oil Characterization Produced Through Vaporization By Exhaust Gas Of Mini-Jet Turbine Engine, Hossein Daniel Bahaghighat

Masters Theses

"Obscurants have been used for centuries to conceal and protect military assets from direct enemy attack, or as a signal between units. Obscurants still play a significant role in protecting soldiers on the battlefield. This research was geared towards development of highly efficient man portable obscurant generation system to demonstrate its use with biogenic oils as the obscurants. The research reported in the thesis was directed evaluating the performance of a mini-jet based generator in the laboratory and field with two different obscurant oils, Fog Oil (FO) the oil used by the US Army at present and potential replacement oil …

Polymer Reinforced Aerogels And Composites A. Polyimide Crosslinked Aerogels B. Silica-Polymethylmethacrylate Composites, Vishal U. Patil

Masters Theses

"Crosslinking of aerogels is a promising approach to combine the advantages of inorganic and polymeric materials. In the present study, two types of polyimide-silica hybrid aerogels, APTES-BTDA-MDA (mol ratio: 2:2:1) and APTES-BTDA-MDA (mol ratio: 2:3:2), were synthesized using a sol-gel process followed by heating in order to imidize the polyamic acid that is formed quickly and is covalently bonded to silica. The hybrid aerogels were made using 3-aminopropyltriethoxysilane (APTES) endcapped polyamic acids and tetramethoxysilane (TMOS) as precursors. Polyimide crosslinked aerogels were characterized by TGA, SEM, FT-IR, BET, solid state NMR and gas pycnometry. These hybrid aerogels exhibit high thermal stability …

Friction Stir Spot Welding Of Aluminum Alloys, Wei Yuan

Masters Theses

"Efforts to reduce vehicle weight and improve safety performance have resulted in increased application of light-weight aluminum alloys and a recent focus on the weldability of these alloys. Friction stir spot welding (FSSW) is a solid state welding technique (derivative from friction stir welding (FSW), which was developed as a novel method for joining aluminum alloys). During FSSW, the frictional heat generated at the tool-workpiece interface softens the surrounding material, and the rotating and moving pin causes material flow. The forging pressure and mixing of the plasticized material result in the formation of a solid bond region. The present work …

Friction Stir Form Welding Of Aluminum Structures, Kamini Ashokkumar Gupta

Masters Theses

"The objective of this work was to demonstrate the applicability of friction stir welding (FSW) technology in the automotive industry. Increasing fuel prices, stringent safety and emission norms are continuously striving automakers to make lightweight, fuel efficient vehicles. Automotive engineers are researching for alternate materials in order to meet weight savings targets. Use of aluminum in place of steel in a car has been increasing for making lightweight vehicles. Conventional welding and spot welding are used as preferred joining methods by the automotive industry. However, if aluminum is used in place of steel alternate joining methods are to be researched. …

Staying Within The Margins: The Educational Stories Of First-Generation, Low-Income College Students, Diane Lyn Cole

Dissertations and Theses

his research addressed educational persistence among first-generation, low-income college students. The educational paths of 22 first-generation, low-income undergraduate students attending a large, urban university in the Northwest region of the United States were examined through a narrative framework. Half of the participants had persisted from year one to year two, and the other half left the university after their first year. Analytic procedures consisted of thematic qualitative coding, an analysis of student trajectories over educational histories, and the reconstruction of narrative stories. Data were used to examine: (1) How first-generation, low-income students understood and described their journey through their first …

Signature Identification In The Light Of Science And Experience, Roger C. Park

Faculty Scholarship

No abstract provided.

Conceptual Hurdles To The Application Of Atkins V. Virginia, Lois A. Weithorn

Faculty Scholarship

No abstract provided.

The Text Of The New Testament: Its Transmission, Corruption, And Restoration, 4th Ed. [Review] / Metzger, Bruce And Bart Ehrman, Terry Dwain Robertson

Andrews University Seminary Studies (AUSS)

No abstract provided.

America, Amerikkka, Elect Nation And Imperial Violence [Review] / Reuther, Rosemary Radford, Trevor O'Reggio

Andrews University Seminary Studies (AUSS)

No abstract provided.

Access Assured: Restoring Progressivity In The Tax And Spending Programs For Higher Education, Kerry A. Ryan

All Faculty Scholarship

Presently, the federal government subsidizes the higher education expenses of individual college students through two distribution channels: the tax system and the transfer system. Under each subsystem, there are a multitude of programs available to assist students in meeting their postsecondary educational expenses. The proliferation of so many forms of federal student aid raises issues of intra- and inter-program effectiveness. In their current form, the tax benefits for higher education do not get the right amount to the right people at the right time. The federal college spending programs, on the other hand, get the right amount to the right …

Corporate Social Responsibility Of Multinational Enterprises And The International Business Law Curriculum, Constance Z. Wagner

All Faculty Scholarship

The author argues for expanded coverage of corporate social responsibility in the U.S. law school curriculum. Corporate social responsibility is of increasing importance for businesses, particularly for those companies that conduct multinational operations. Current national legal and regulatory regimes fail to adequately address the social and environmental issues that arise in business operations. As a result, intergovernmental organizations, non-governmental organizations and businesses have begun to promulgate voluntary codes ofconduct. These codes touch on such subjects as core labor standards, environmental protection, bribery offoreign government officials in international business and human rights. Examples include the Organization for Economic Cooperation and Development …

Resolving Conflicts Between Humans And The Threatened Louisiana Black Bear, Walter Cotton

Human–Wildlife Interactions

The Louisiana black bear (Ursus americanus luteolus) is one of 16 subspecies of American black bear. At the time of English settlement, this subspecies was abundant throughout Louisiana, the southern two-thirds of Mississippi, eastern Texas, and extreme southern Arkansas. By the 1950s, Louisiana black bears had been extirpated from most of their original range due to habitat destruction and fragmentation and over-harvest by hunters (Leigh and Chamberlain 2008). It is believed that only about 100 black bears remained; existing in isolated, extremely rural areas of eastern Louisiana. Bears became so scarce during the 1960s that the Louisiana Department …

Eat This Book: A Conversation In The Art Of Spiritual Reading [Review] / Petersen, Eugene H., Lael O. Caesar

Andrews University Seminary Studies (AUSS)

No abstract provided.

Sin, Impurity, Sacrifice, Atonement: The Priestly Conceptions [Review] / Sklar, Jay, Gerald A. Klingbeil

Andrews University Seminary Studies (AUSS)

No abstract provided.

The Book Of Proverbs: Chapters 15-31 [Review] / Waltke, Bruce K., Lael O. Caesar

Andrews University Seminary Studies (AUSS)

No abstract provided.

Bridging The Gap: Ritual And Ritual Texts In The Bible [Review] / Gerald A. Klingbeil, Roy E. Gane

Andrews University Seminary Studies (AUSS)

No abstract provided.