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1998

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Bestsellers In Mathematics 1997, Francois Crowell Jun 1998

Bestsellers In Mathematics 1997, Francois Crowell

Against the Grain

No abstract provided.


Computational Geometry Column 33, Joseph O'Rourke Jun 1998

Computational Geometry Column 33, Joseph O'Rourke

Computer Science: Faculty Publications

Several recent SIGGRAPH papers on surface simplification are described.


Utilization Of The Meteorological Data In The Prediction Of The Potential Of The Renewable Energy Resources In The United Arab Emirates, Nasser A.N. Albaloushi Jun 1998

Utilization Of The Meteorological Data In The Prediction Of The Potential Of The Renewable Energy Resources In The United Arab Emirates, Nasser A.N. Albaloushi

Theses

There has been an increasing world interest in clean renewable energies ( mainly radiation and wind energies ) due to the minimal environmental problems resulting from their use. The continuous depletion of conventional energy resources and the growing world concern about the environment have lead to extensive research and development efforts in order to improve the energy conversion efficiencies and economics of devices utilizing solar energy. However, it is important to identify first the potential of available energy resources in the site where renewable energy is to be utilized.

Meteorological information are critical to the assessment of the energy resources …


Fostering Reflective Thinking In First-Semester Calculus Students, Pamela Crawford Jun 1998

Fostering Reflective Thinking In First-Semester Calculus Students, Pamela Crawford

Dissertations

This study focuses on the fostering of reflective thinking in students in a reform calculus course through completion of homework assignments incorporating reflective tasks, and the effect of these assignments on student understandings of calculus and conceptions of mathematics. The study, conducted in Fall 1997, involved two sections of first-semester calculus at a large midwestern university and used quantitative (n = 25, 18) and qualitative (n = 7) techniques.

Homework assignments incorporating reflective tasks included asking students to compare and contrast textbook ideas; to write about how obstacles were overcome as they attempted exercises; to develop concept maps organizing and …


General Formulation Of The Semirelativistic Approach To Atomic Sum Rules, P.T. Leung, Scott M. Cohen Jun 1998

General Formulation Of The Semirelativistic Approach To Atomic Sum Rules, P.T. Leung, Scott M. Cohen

Physics Faculty Publications and Presentations

A general scheme is presented for obtaining systematic relativistic corrections to quantum-mechanical sum rules for various calculations in atomic physics. The single-particle picture and the Foldy-Wouthuysen transformation [Phys. Rev. 78, 29 (1950)] are adopted to derive such corrections. Results are obtained for the ldquogeneralized Bethe sums,rdquo which include all higher moments of the energy transfer, and explicit results are given to the lowest order of relativistic corrections.


Effect Of Postmenopausal Hormone Replacement Therapy On Heart Rate Variability, Diane Todd Pace Jun 1998

Effect Of Postmenopausal Hormone Replacement Therapy On Heart Rate Variability, Diane Todd Pace

Theses and Dissertations (ETD)

Minimal research has addressed effects of postmenopausal hormone replacement therapy (HRT) on heart rate variability (HRV), a measure of cardiovascular autonomic balance and a predictor of cardiac morbidity/mortality. Using an exploratory, pre-test/post-test design to describe HRV in postmenopausal women (PMW) before/after six weeks of HRT, twenty-four Black (n=15) and White (n=9) women, (mean age=55±4 years), were recruited from two primary care clinics (n=20) and one church population (n=4) in a large urban midsouth community. Cardiovascular risk factors for the sample included chronic illnesses of DM (n=8), HRT (n=11), both DM and HRT (n=4), smoking (n=9), non-exercise (n=11), and obesity quantified …


Empirical Studies Of A Safe Regression Test Selection Technique, Gregg Rothermel, Mary Jean Harrold Jun 1998

Empirical Studies Of A Safe Regression Test Selection Technique, Gregg Rothermel, Mary Jean Harrold

School of Computing: Faculty Publications

Regression testing is an expensive testing procedure utilized to validate modified software. Regression test selection techniques attempt to reduce the cost of regression testing by selecting a subset of a program’s existing test suite. Safe regression test selection techniques select subsets that, under certain well-defined conditions, exclude no tests (from the original test suite) that if executed would reveal faults in the modified software. Many regression test selection techniques, including several safe techniques, have been proposed, but few have been subjected to empirical validation. This paper reports empirical studies on a particular safe regression test selection technique, in which the …


Finite Size Scaling In The Thin Film Limit, C. Waldfield, D. Welipitiya, T. Mcavoy, Peter A. Dowben, Elio Vescovo Jun 1998

Finite Size Scaling In The Thin Film Limit, C. Waldfield, D. Welipitiya, T. Mcavoy, Peter A. Dowben, Elio Vescovo

Peter Dowben Publications

The thickness dependent spin-polarized electronic structure of strained thin and ultrathin films of Gd is characterized by a distinct change in the critical exponent λ in the formalism of finite size scaling. The reduced critical exponent in the ultrathin films can be correlated to the increased dominance of the surface magnetic structure and the increasing paramagnetic-like behavior of the bulk. ©1998 American Institute of Physics.


Redistributing Income Upward Through The Cost-Plus Reimbursement Terms Of Subgovernment Contracts, F. Gregory Hayden, Steven R. Bolduc Jun 1998

Redistributing Income Upward Through The Cost-Plus Reimbursement Terms Of Subgovernment Contracts, F. Gregory Hayden, Steven R. Bolduc

Department of Economics: Faculty Publications

This is a case study designed to test the thesis (drawn from political science literature) that the power of "subgovernments" in the United States has decreased and, in particular, claims a demise in the power of the atomic energy subgovernment as one proof for the thesis. The subgovernment approach to explaining policymaking in the United States "is based on the observation that relatively small groups of actors dominate certain sectors of the political system" [Duffy 1997, 4]. One function of such subgovernments is to redistribute income upward through the cost-plus reimbursement terms of government contracts.

The subgovernmental institutions-also referred to …


Immobilization Diffusion In R2Fe17 Nitrides, Ralph Skomski, S. Wirth Jun 1998

Immobilization Diffusion In R2Fe17 Nitrides, Ralph Skomski, S. Wirth

Ralph Skomski Publications

The diffusion of nitrogen in R2Fe17 intermetallics is investigated by an approach which reconciles the solid-solution and immobilization theories of nitrogen diffusion. It turns out that two-sublattice diffusions may yield sharp concentration profiles but leave the phase structure of the nitride unchanged. Beside the reaction time and a local relaxation time there exists a global relaxation time which governs the smoothing of concentration gradients. Due to the large number of unknown energy parameters involved it is difficult to make quantitative predictions, but in general the diffusion behavior depends on factors such as the use of N2 …


Finite-Temperature Behavior Of Anisotropic Two-Sublattice Magnets, Ralph Skomski Jun 1998

Finite-Temperature Behavior Of Anisotropic Two-Sublattice Magnets, Ralph Skomski

Ralph Skomski Publications

The finite-temperature magnetism of rare-earth transition-metal intermetallics is investigated by extending the n-component vector spin model to two-sublattice magnets. Mean-field analysis shows that the influence of the rare-earth anisotropy on the mean-field Curie temperature is much smaller than expected from the low-temperature rare-earth anisotropy. The use of ultraspherical polynomials yields a generalization of the famous m (m+1)/2 power-law exponent to m (m+n-2)/( n-1).


Micromagnetic Localization, Ralph Skomski Jun 1998

Micromagnetic Localization, Ralph Skomski

Ralph Skomski Publications

The localization of nucleation modes in inhomogeneous ferromagnets and its influence on the coercivity are investigated. From the formal analogy between quantum mechanics and micromagnetics follows that anisotropy inhomogeneities may cause localization. The nucleation modes of one-dimensional arrays, such as multilayers composed of hard and soft magnetic materials, are localized even if the superlattice exhibits a nearly ideal periodicity. Gaussian distributions of the layer thicknesses lead to Urbach tails and very low coercivities, but a maximum thickness lm of the soft layers suppresses the Urbach tails. The related problem of magnetic viscosity leads to a supersymmetric Fokker–Planck description where …


Simulation Of The Hybrid Fuzzy-Boolean Finite State Machine (Hfb-Fsm), Hamed Shakouri Jun 1998

Simulation Of The Hybrid Fuzzy-Boolean Finite State Machine (Hfb-Fsm), Hamed Shakouri

Masters Theses

Several models of fuzzy finite-state automata have been proposed in the literature. One model which benefits from the existing algorithms for designing Boolean finite-state machines, has been proposed by J. L. Grantner [8]. This model, which is called Hybrid Fuzzy-Boolean Finite State Machine (HFB-FSM), along with its algorithmic design procedure, can be used for implementing dynamic linguistic systems [7,8,13]. In this thesis we have developed a simulation program for the HFB-FSM model using C++ programming language. In order to simulate a HFB-FSM model, the user provides the information defining the system's behavior. Based on the algorithm proposed in [8], the …


A Measurement Of The Inclusive B → Sγ Branching Ratio, R. Barate, Manoj Thulasidas Jun 1998

A Measurement Of The Inclusive B → Sγ Branching Ratio, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The avour changing neutral current decay b ! s has been detected in hadronic Z decays collected by ALEPH at LEP. The signal is isolated in lifetime-tagged b b events by the presence of a hard photon associated with a system of high momentum and high rapidity hadrons. The background processes are normalised from the data themselves. The inclusive branching ratio is measured to be (3:11 0:80stat 0:72syst) 104 ; consistent with the Standard Model expectation via penguin processes


The Prairie Naturalist Volume 30, No.2 June 1998 Jun 1998

The Prairie Naturalist Volume 30, No.2 June 1998

The Prairie Naturalist

REPRODUCTIVE SUCCESS OF SHARP-TAILED GROUSE IN CENTRAL MONTANA ▪ K. R. Bousquet and J. J. Rotella

EFFECTS OF DROUGHT ON RECLAIMED GRASSLANDS IN WESTERN NORTH DAKOTA ▪ D. R. Kirby, L. M. Stewart, K. D. Krabbenhoft, and D. J. Nilson

MALE COMMON NIGHTHAWK USE OF GRAVEL ROADS AT NIGHT ▪ R. G. Poulin, L. D. Todd, and R. M. Brigham

RESTORATION AND STATUS OF THE RUFFED GROUSE IN KANSAS ▪ R. D. Rodgers, R. W. Wells, K. E. Church, R. L. Whiteaker, M. T. McFadden, D. S. Lekie, R. A. Bergquist, H. J. Abel, and R. D. Applegate

PITFALL TRAPPING …


Measurement Of Autonomic Function In Renal Disease And Diabetes, Ann King Cashion Jun 1998

Measurement Of Autonomic Function In Renal Disease And Diabetes, Ann King Cashion

Theses and Dissertations (ETD)

Renal disease and diabetes lead to dysautonomia resulting in consequences ranging from gastroparesis to sudden death. New technologies to detect dysautonomia, such as 24-hr heart rate variability, are being evaluated and compared to traditional evoked tests. These advances have, however, lead to a lack of standardization in testing batteries, procedures, and reporting formats. This series of 3 studies psychometrically assessed measures of autonomic function (AF) and explored relationships among objective and subjective measures in healthy adults and uremic patients. Participants underwent evoked tests that included change in heart rate with deep breathing and Valsalva. In addition, measures of 24-hr HRV …


Optimizing Conjunctive Water Use For Sustainable Production: Tools For The Management Spectrum, Richard C. Peralta, Shengjun J. Wu, H. J. Morel-Seytoux, Fernando Chanduvi Jun 1998

Optimizing Conjunctive Water Use For Sustainable Production: Tools For The Management Spectrum, Richard C. Peralta, Shengjun J. Wu, H. J. Morel-Seytoux, Fernando Chanduvi

Civil and Environmental Engineering Faculty Publications

Making best use of water resources requires coordinating use of groundwater and surface waters--conjunctive use. Conjunctive water management is important on the regional (watershed or aquifer), water district and field scales. Goals might differ for the different administrative levels. A regionally optimal water management strategy is not necessarily optimal for water district managers and individual farmers. Interactions between levels are affected by laws, regulations, traditions and public pressure. To help each organizational level develop water management strategies that best achieve its goals, computer simulation/optimization (S/O) models are useful. Such S/O models couple water flow and transport simulation techniques with formal …


A Computational Framework For Telemedicine, Ian Foster, Gregor Von Laszewski, Brian Toonen, George K. Thiruvathukal Jun 1998

A Computational Framework For Telemedicine, Ian Foster, Gregor Von Laszewski, Brian Toonen, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

Emerging telemedicine applications require the ability to exploit diverse, geographically distributed resources. These applications use high-speed neworks to integrate supercomputers, large databases, archival storage devices, advanced visualization devices, and/or sophisticated instruments. This form of networked virtual supercomputers is also known as metacomputers and is being used by many other scientific applications areas. In this article, we analyze requirements necessary for a telemedicine computing infrastructure and compare them with requirements found in a typical metacomputing environment. We will show that metacomputing environments can be used to enable a more powerful and unified computational infrastructure for telemedicine. The Globus metacomputing environment can …


Observation Of Oscillations Between Degenerate Bound-State Configurations In Rapidly Autoionizing Two-Electron Atoms, M. B. Campbell, Thomas J. Bensky, Robert R. Jones Jun 1998

Observation Of Oscillations Between Degenerate Bound-State Configurations In Rapidly Autoionizing Two-Electron Atoms, M. B. Campbell, Thomas J. Bensky, Robert R. Jones

Physics

The oscillation between bound-state configurations in a rapidly autoionizing three-body Coulomb system has been directly observed. Using a 500-fsec laser pulse, calcium atoms are excited to the pure 4p3/215d two-electron configuration at an energy greater than 3 eV above the ionization limit. As a result of configuration interaction, the electrons scatter coherently into multiple bound and continuum configurations. The oscillation between the degenerate 4p1/2n′d and 4p3/2nd modes as well as autoionization into 4s1/2εl, 3d3/2εl, and 3d5/2εl …


Evaluation Of Mortality Factors And Risk Analysis For The Design Of An Integrated Pest Management System, Olivier Roux, Johann Baumgärtner Jun 1998

Evaluation Of Mortality Factors And Risk Analysis For The Design Of An Integrated Pest Management System, Olivier Roux, Johann Baumgärtner

All Peer-Reviewed Publications

A probabilistic approach of survival analysis based on the theory of competing risks was applied to the potato tuber moth Phthorimaea operculella (Zeller) affecting tubers in Tunisian rustic stores. Exponential curve of death, i.e. constant force of mortality functions were used in a case study on a cohort time basis. The additive property of crude cause-specific forces of mortality is used to combine mortality factors, which permits to judge different control strategies. In an integrated pest management perspective, the effect of basic mortalities, i.e innate and dispersal related mortalities is recombined with native natural enemies. Thereafter, we calculate the force …


Does The Oswestry Or Sf-36 Help A Therapist To Predict Treatment Classification, Amy Crawford, Denese D. Kaufeldt-Soliz Jun 1998

Does The Oswestry Or Sf-36 Help A Therapist To Predict Treatment Classification, Amy Crawford, Denese D. Kaufeldt-Soliz

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the relationship of two disability questionnaires, the Oswestry Low Back Pain Disability Questionnaire (Oswestry) and the Medical Outcome Study Short Form-36 (SF-36), and a standardized physical examination and diagnostic classification system. The physical examination was performed by the evaluating therapists from the clinic and classification was determined by the evaluating therapists and the investigators to ensure correct subject placement into treatment Stages la, lb, or II. Data collection occurred at an outpatient physical therapy clinic in a metropolitan area health maintenance organization, where a sample of 221 subjects with low back pain …


Database Selection Techniques For Routing Bibliographic Queries, Ee Peng Lim, Wee-Keong Ng, Jian Xu, Yinyan Cao Jun 1998

Database Selection Techniques For Routing Bibliographic Queries, Ee Peng Lim, Wee-Keong Ng, Jian Xu, Yinyan Cao

Research Collection School Of Computing and Information Systems

No abstract provided.


Querying Structured Web Resources, Ee Peng Lim, Cheng Hai Tan, Boon Wan Lim, Wee-Keong Ng Jun 1998

Querying Structured Web Resources, Ee Peng Lim, Cheng Hai Tan, Boon Wan Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

To provide query facilities over Web resources, several web search engines such as Yahoo, Altavista, Infoseek, etc. have been developed. Most prominently, web search engines have been used to index all web pages on the Internet. The queries supported by these search engines are mainly designed to reveal web pages that meet the search criteria specified by the users. In this way, the search engines have been used as some kind of discovery tools. The queries supported are known as discovery queries. On the other hand, a web search engine can also be used to index and support queries over …


Process Lower Deviation Selection Policy For Load Distribution, Louay Farag Jun 1998

Process Lower Deviation Selection Policy For Load Distribution, Louay Farag

Archived Theses and Dissertations

No abstract provided.


Aquila X-1: A Low-Inclination Soft X-Ray Transient, T. Shahbaz, J. R. Thorstensen, P. A. Charles, N. D. Sherman Jun 1998

Aquila X-1: A Low-Inclination Soft X-Ray Transient, T. Shahbaz, J. R. Thorstensen, P. A. Charles, N. D. Sherman

Dartmouth Scholarship

We have obtained I-band photometry of the neutron star X-ray transient Aql X-1 during quiescence. We find a periodicity at 2.487 cycles d−1, which we interpret as twice the orbital frequency (19.30±0.05 h). Folding the data on the orbital period, we model the light-curve variations as the ellipsoidal modulation of the secondary star. We determine the binary inclination to be 20°–30° (90 per cent confidence) and also determine the 95 per cent upper limits to the radial velocity semi-amplitude and rotational broadening of the secondary star to be 117 and 50 km s−1, respectively.


Ichnology Of Holocene Carbonate Eolianites On San Salvador Island, Bahamas: Diversity And Significance, H. Allen Curran, Brian White Jun 1998

Ichnology Of Holocene Carbonate Eolianites On San Salvador Island, Bahamas: Diversity And Significance, H. Allen Curran, Brian White

Geosciences: Faculty Publications

Reprinted from: H. Allen Curran and John E. Mylroie (eds.), Proceedings of the 9th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Bahamian Field Station


A Mössbauer Spectral Study Of Tb₂Fe₁₇ And The Tb₂Fe₁₇₋ₓsiₓ Solid Solutions, Dimitri Hautot, Gary J. Long, Peter C. Ezekwenna, Fernande Grandjean, D. P. Middleton, K. H. J. Buschow Jun 1998

A Mössbauer Spectral Study Of Tb₂Fe₁₇ And The Tb₂Fe₁₇₋ₓsiₓ Solid Solutions, Dimitri Hautot, Gary J. Long, Peter C. Ezekwenna, Fernande Grandjean, D. P. Middleton, K. H. J. Buschow

Chemistry Faculty Research & Creative Works

The Mössbauer spectra of a series of rhombohedral Tb2Fe17-xSix solid solutions, with x equal to 0, 1, 2, and 3, have been measured as a function of temperature. Although the spectra of Tb2Fe17 change substantially upon cooling from 295 to 85 K, it has been possible to fit them with a consistent seven sextet model corresponding to a basal magnetization. The spectral analysis yields reasonable hyperfine parameters and the expected changes with temperature. The resulting weighted average effective iron recoil mass of 66 g/mol and the Mössbauer temperature of 395 K are …


Location Independent Names For Nomadic Computers, David Steere, Mark Morrissey, Peter Geib, Calton Pu, Jonathan Walpole Jun 1998

Location Independent Names For Nomadic Computers, David Steere, Mark Morrissey, Peter Geib, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Recent advances in the Domain Name System (DNS) and the Dynamic Host Configuration Protocol (DHCP) have enabled a new approach to supporting mobile users: location independent naming. In this approach, machines use the same hostname from any internet location, but use an IP address that corresponds to their current location. We describe a protocol that implements location independent naming for nomadic computers, i.e., machines that do not need transparent mobility. Our protocol allows hosts to move across security domains, uses existing protocols, and preserves existing trust relationships. Therefore, it preserves the performance and security of normal IP for nomadic computers …


Species Ratings For Landscape Tree Appraisal In Utah, Michael R. Kuhns Jun 1998

Species Ratings For Landscape Tree Appraisal In Utah, Michael R. Kuhns

All Current Publications

This fact sheet establishes species ratings to be used by tree appraisal experts with the trunk formula method for appraising the monetary value of trees in Utah.


Analytical And Experimental Study Of Investment Casting With Laser Stereolithography Models, Wen-Long Yao May 1998

Analytical And Experimental Study Of Investment Casting With Laser Stereolithography Models, Wen-Long Yao

Dissertations

This dissertation presents an analytical and experimental investigation of ceramic shell cracking during the burnout process in investment casting with internally webbed laser stereolithography (SLA) patterns. Included in the consideration are the cracking temperature of the ceramic shell, the web link buckling temperature, and the glass transition temperature of the epoxy resin. The hypothesis is that shell cracking will occur when the cracking temperature is lower than the glass transition temperature and the web buckling temperature.

An analytical and experimental study has been conducted, with the cross-sectional area, the span length of the web structure, and the shell thickness being …