Digital Commons Network^™

Volcanic Caves Of East Africa - An Overview, Jim W. Simons

International Journal of Speleology

Numerous Tertiary to recent volcanoes are located in East Africa. Thus, much of the region is made up volcanic rock, which hosts the largest and greatest variety of East Africas caves. Exploration of volcanic caves has preoccupied members of Cave Exploration Group of East Africa (CEGEA) for the past 30 years. The various publications edited by CEGEA are in this respect a treasure troves of speleological information. In the present paper an overview on the most important volcanic caves and areas are shortly reported.

Guano Mining In Kenyan Lava Tunnel Caves, Jim W. Simons

International Journal of Speleology

Commercial mining of bat guano for agricultural fertilizer only became possible in Kenya through discovery of major deposits in the lava tunnel caves of Mt. Suswa and the North Chyulu Hills in the early 1960’s. This paper provides historical information leading up to the guano mining, describes the cave deposits, outlines the mining under-takings, and provides information on the guano producing bats and insect faunas. The results of guano analyses, details of the tonnages extracted and sold to recipients between 1966 to 1984, and some benefits which resulted from its use on crops are given. A brief outline of attempts …

Lave Caves Of Kilimanjaro. Mawenzi Lava Tubes, Clive Ward

International Journal of Speleology

This is the first short report on the exploration of lava tubes in the upper part of Kilimanjaro. The area seems to be extremely interesting from vulcanospeleological point of view.

The Origin Of Tubular Lava Stalactites And Other Related Forms, Kevin Allred, Carlene Allred

International Journal of Speleology

Tubular lava stalactites are often found in lava tubes. Field observations, sample analysis, and comparative studies indicate that these are segregations extruded during cooling from partially crystallized lava al about 1,070 - 1,000 °C. Retrograde boiling (gas pressure) within the lava provides a mechanism to expel the interstitial liquid. In addition to tubular lava stalactites, a variety of other lava features can also result, such as lava helictites, lava coralloids, barnacle-like stretched lava, runners, runner channels, and some lava blisters and squeeze-ups.

Charged Particles And Neutral Kaons In Photoproduced Jets At Hera, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

Charged particles (h±) and K0 mesons have been studied in photoproduced events containing at least one jet of ET > 8 GeV n a pseudorapidity interval (-0.5, 0.5) in the ZEUS laboratory frame. Distributions are presented in terms of transverse momentum, pseudorapidity and distance of the particle from the axis of a jet. The properties of h± within the jet are described well using the standard settings of PYTHIA, but the use of the multiparton interaction option improves the description outside the jets.

Characterisations Of Slender Groups, Thomas Kelly

Masters

Chapter 1 summarises some necessary results concerning free, divisible, algebraically compact and cotorsion groups. A detailed proof of the well-known result that the Specker group P is ℵ1 free but not free is included and the structure of the quotient group P/S is determined. The basic properties of slender groups are examined and cotorsion groups of cardinality less than or equal to that of the continuum are shown to be epimorphic images of P. Chapter II presents Nunke’s characterisation of slender groups. This approach establishes that homomorphic images of the Specker group P are the direct sum of a cotorsion …

Transitive And Fully Transitive Groups, Steve Files, Brendan Goldsmith

Articles

The notions of transitivity and full transitivity for abelian p-groups were introduced by Kaplansky in the 1950s. Important classes of transitive and fully transitive p-groups were discovered by Hill, among others. Since a 1976 paper by Corner, it has been known that the two properties are independent of one another. We examine how the formation of direct sums of p-groups affects transitivity and full transitivity. In so doing, we uncover a far-reaching class of p-groups for which transitivity and full transitivity are equivalent. This result sheds light on the relationship between the two properties for all p-groups.

Usable Software And It's Attributes: A Synthesis Of Software Quality: European Community Law And Human-Computer Interaction., Ronan Fitzpatrick, Catherine Higgins

Conference papers

Strategic managers and IS professionals who are responsible for specifying, acquiring and producing quality software products are not supported by the endless flow of new international standards, legislation and user requirements. In order to clarify the current situation for everybody concerned with software quality, and especially those interested in usability, there is a need for a new review and evaluation of the various strands that contribute to software quality. By way of review this paper recalls the original software quality factors which were defined twenty years ago by McCall et al. and presents a methodical analysis and synthesis of three …

Comparative Study Of Stock Trend Prediction Using Time Delay, Recurrent And Probabilistic Neural Networks, Donald C. Wunsch, Emad W. Saad, Danil V. Prokhorov

Electrical and Computer Engineering Faculty Research & Creative Works

Three networks are compared for low false alarm stock trend predictions. Short-term trends, particularly attractive for neural network analysis, can be used profitably in scenarios such as option trading, but only with significant risk. Therefore, we focus on limiting false alarms, which improves the risk/reward ratio by preventing losses. To predict stock trends, we exploit time delay, recurrent, and probabilistic neural networks (TDNN, RNN, and PNN, respectively), utilizing conjugate gradient and multistream extended Kalman filter training for TDNN and RNN. We also discuss different predictability analysis techniques and perform an analysis of predictability based on a history of daily closing …

Measurement Of The He Ground State Lamb Shift Via The Two-Photon 1 1S-2 1S Transition, Scott D. Bergeson, A. Balakrishnan, K. G. H. Baldwin, T. B. Lucatorto, J. P. Marangos, T. J. Mcilrath, T. T. O'Brian, S. L. Rolston, C. J. Sansonetti, Jesse Wen, N. Westbrook, C. H. Cheng, E. E. Eyler

Faculty Publications

We have extended two-photon Doppler-free spectroscopy to the vacuum ultraviolet spectral region, to accurately measure the He 1¹S-2¹S transition at 120 nm. Our result is 4984872315(48) MHz. This yields a ground state Lamb shift of 41104(48) MHz, in fair agreement with theory and other experiments. This approach has the potential for significantly better accuracy once improvements in the laser and the wavelength metrology are implemented.

Reading And Writing In The Engineering Classroom : An Ethnographic Exploration / Patricia Anne John., Patricia Anne John

Pre-2000 Student Works

No abstract provided.

Kajian Kes Tentang Pengajaran Matematik Pensyarah Institut Teknologi Mara (Jilid Ii) / Rokiah Embong., Rokiah Embong

Pre-2000 Student Works

No abstract provided.

Digital Implementation Of Artificial Neural Networks / Saffih Faycal, Faycal Saffih

Pre-2000 Student Works

This thesis is concerned with the philosophy and the strategies related to the digital implementations of artificial neural networks ANN. An open and deep insight of the biological origin of ANN as well as its tidy relation with physics through statistical mechanics and the Hopficld revolutionary concept of computational energy (See Ref (4] of Chapter 2) is given. The Very Large-Scale Integration VLSI implementation of ANN (mainly digital) with its diverse methodologies, strategies and goals also discussed. The notion of parallelism that was the comer stone of the third chapter in the processing (or the hardware) point-of-view and is enhanced …

Digital Implementation Of Artificial Neural Networks / Saffith Faycal, Saffith Faycal

Pre-2000 Student Works

No abstract provided.

Undergraduate Bulletin Of The University Of San Diego 1998-2000, University Of San Diego

Undergraduate Course Catalogs (1973- )

220 pages : illustrations, photographs ; 28 cm

Operations And Spectral Sequences. I, James M. Turner

University Faculty Publications and Creative Works

Using methods developed by W. Singer and J. P. May, we describe a systematic approach to showing that many spectral sequences, determined by a filtration on a complex whose homology has an action of operations, possess a compatible action of the same operations. As a consequence, we obtain \V. Singer's result for Steenrod operations on Serre spectral sequence and extend A. Bahri's action of Dyer-Lashof operations on the second quadrant Eilenberg-Moore spectral sequence.

Market-Based Assets And Shareholder Value: A Framework For Analysis, Rajendra Kumar Srivastava, Tasadduq A. Shervani, Liam Fahey

Research Collection Lee Kong Chian School Of Business

The authors develop a conceptual framework of the marketing-finance interface and discuss its implications for the theory and practice of marketing. The framework proposes that marketing is concerned with the task of developing and managing market-based assets, or assets that arise from the commingling of the firm with entities in its external environment. Examples of market-based assets include customer relationships, channel relationships, and partner relationships. Market-based assets, in turn, increase shareholder value by accelerating and enhancing cash flows, lowering the volatility and vulnerability of cash flows, and increasing the residual value of cash flows. ABSTRACT FROM AUTHOR Copyright of Journal …

The Relationship Between Student Characteristics And Math Achievement When Using Computer Spreadsheets., Jeanne Heindel Gasiorowski

Graduate Theses, Dissertations, and Problem Reports (ETD)

The use of computer hardware and software technology in schools is on the rise while there are increasing demands for success in mathematics by all students, despite diverse backgrounds. The problem is to determine the characteristics of students who most benefit from the use of spreadsheet software as a cognitive tool to assist them as they learn to organize and analyze data. For a period of six weeks, 114 seventh grade students received standard instruction in their mathematics classes in basic statistics/data analysis content. Concurrently, in a separate computer class, the students received instruction which focused on the use of …

Parametric Study Of Dust Generation With Rock Ridge Breakage Analysis Using A Simulated Continuous Miner., Venkata Babu Achanti

Graduate Theses, Dissertations, and Problem Reports (ETD)

Efficient rock breakage is a result of optimum use of available resources in a continuous mining system. Research demonstrates that specific respirable dust must be kept at a minimum in order to produce the optimum parameters of rock breakage process. A cutting process that induces large chips of cut product results in minimum respirable dust. To produce larger chips of cut product, a correct inter-play of several bit geometry related parameters is essential. As the ridges/lands between two adjacent grooves are removed, a free surface is available for subsequent cuts. The nature of ridge failure is a function of the …

Time Series Forecasting Of Mexican Trade Prices., Horacio Cardiel Perez

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main purpose of this study is to address the question of how price forecasts can be produced in an accurate, reliable, and cost-effective form for planning and policy purposes in Mexican agriculture. The need for this stems from the recent opening of the Mexican economy, which resulted in a decrease government intervention, such that market demand, supply and prices are now influenced more by international events. Thus, this work investigates the application of univariate time series models to forecasting the trade prices for corn, dry beans, and sorghum in an import side, and tomatoes, broccoli, coffee, and sugar as …

Economic Valuation Models For Insurers, David F. Babbel, Craig B. Merrill

Faculty Publications

Recently much attention has been given to the approaches insurers undertake in valuing their liabilities and assets. For example, in 1994 the American Academy of Actuaries created a Fair Valuation of Liabilities Task Force to address the issue [see Doll et al. (1998), Reitano (1997), Babbel (1997, 1998b), Babbel and Merrill (1996), and Merrill (1997)]. In 1997, the Academy established a Valuation Law Task Force and a Valuation Tools Working Group to investigate the various valuation approaches extant and to recommend the models best suited to the task.

Much of the literature on valuation has focused on the strengths and …

Synthesis And Evaluation Of Novel Polymeric Stationary Phases For Capillary Liquid Chromatography And Electrochromatography., Zhixin Jessica Tan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The stationary phase is at the heart of chromatographic separation techniques. In the pursuit of higher separation efficiency and resolving power, methods for the synthesis of novel polymeric stationary phases were developed. These stationary phases were evaluated using microscale separation techniques that have inherent high efficiency: open-tubular liquid chromatography (OT-LC), open-tubular capillary electrochromatography (OT-CEC), and packed column capillary electrochromatography (PC-CEC). A new technique was developed for the in situ synthesis of thin film polymer stationary phases inside small diameter fused silica capillaries. This technique allows the use of readily available and inexpensive polyimide jacketed capillaries, and provides greater control over …

A Computational Study Of M-M Multiple Bonding In Ph2mmph2N-, Where M = B Or Al, And N = 0, 1, Or 2, Edward L. Hamilton, Justin G. Pruis, Roger L. Dekock, Karl J. Jalkanen

University Faculty Publications and Creative Works

We have completed Hartree-Fock ab initio electronic structure calculations on the series of compounds Ph2MMPh2n, where M = B or Al, and n = 0, 1-, or 2-. The results show that the added one and two electrons upon reduction of the neutral compounds go into the M-M π bond, as expected. The canting of the rings in D2 symmetry is related to the degree of steric repulsion in the compounds. There is no evidence for preferential population of an Al-Al σ* orbital in the dianion of the aluminum compound, and hence we have no ready explanation as to why …

A Manifold That Does Not Contain A Compact Core, Gerard A. Venema

University Faculty Publications and Creative Works

A core of a (noncompact) manifold is a submanifold with the property that the inclusion of the submanifold into the manifold is a homotopy equivalence. It is shown by example that a manifold may fail to contain a compact core even though the manifold has the homotopy type of a finite complex.

Economies Of Scale, Overcapitalization And Asset Pricing In The United States Electric Utility Industry., Russell Rhine

Graduate Theses, Dissertations, and Problem Reports (ETD)

The following dissertation is the consolidation of three research projects in the U.S. electric utility industry. The first essay tests for scale economies in the electric utility industry using a panel data set of fossil fuel and nuclear fuel utilities. In addition, a variable cost function is used as opposed to a total cost function because the assumption of cost minimizing production inputs is not met. That is, electric utilities are overcapitalized. Therefore, the optimal capital stock is estimated and an estimate of economies of scale is generated. Evidence suggests that firms are operating on the negatively sloped portion of …

A Homotopy Equivalence That Is Not Homotopic To A Topological Embedding, Vo Thanh Liem, Yukio Matsumoto, Gerard A. Venema

University Faculty Publications and Creative Works

An open subset W of Sn, n ≥ 6 or n = 4, and a homotopy equivalence f : S2 × Sn-4 → W are constructed having the property that f is not homotopic to any topological embedding.

Depolarized Resonance Light Scattering By Porphyrin And Chlorophyll A Aggregates, Jai Parkash, John H. Robblee, John Agnew, Julio C. De Paula

Chemistry Faculty Scholarship

No abstract provided.

Whitehead's Metaphysics And The Law: A Dialogue, Jay Tidmarsh

Journal Articles

The purposes of this Article are to explore the relationship between Alfred North Whitehead's process philosophy and the nature of law, and to develop from that exploration a theory of "process jurisprudence." To some extent, this Article is a process of interpretation and imagination. Whitehead himself devoted little attention to the nature of law. Therefore, rather than attempting to declare definitively the implications of Whitehead's thought for the nature of law, this Article is structured in the form of a dialogue between "Whitehead" and a lawyer whom I have called "Chris." In Part II, as he discusses his system of …

1998-1999 Usd Facts, University Of San Diego

USD Fact Books (1985- )

No abstract provided.

The Effects Of Foreign Capital Inflows On The Malaysian Economy, 1966-96 / Wong Hwa Kiong., Hwa Kiong Wong

Pre-2000 Student Works

No abstract provided.