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The Total Cosmic Diffuse Gamma-Ray Spectrum From 9 To 30 Mev Measured With Comptel, S C. Kappadath, James M. Ryan, K Bennett, H Bloemen, R Diehl, W Hermsen, Mark L. Mcconnell, V Schonfelder, M Varendorff, G Weidenspointer, C Winkler

Space Science Center

A preliminary COMPTEL Cosmic Diffuse Gamma-Ray (CDG) spectrum from 800 keV to 30 MeV was presented earlier at the 3rd Compton Symposium. The COMPTEL results represent the first significant detection of the CDG radiation in the 9 to 30 MeV range. Using high-latitude data from the first 5 years of the mission we have performed a new detailed measurement of the 9 to 30 MeV spectrum with finer energy binning. The new improved results are in good agreement with our previous estimates and are compatible with power-law extrapolations from higher energies. The measured 9–30 MeV spectra from the Virgo and …

A Time Dependent Model For The Activation Of Comptel, M Varendorff, U Oberlack, G Weidenspointer, R Diehl, R Vandijk, Mark L. Mcconnell, James M. Ryan

Space Science Center

The structure of the CGRO satellite is irradiated by cosmic rays and trapped particles fromradiation belts. These incident particles produce radioactive nuclei in nuclear reactions with the satellite structure. Most of the radiation dose can be attributed to the passages through the South Atlantic Anomaly. The incident particle flux on the COMPTEL instrument is estimated from the event rate of a plastic scintillation detector. This event rate is modeled with a Neural Network simulation. The increase of the event rate during SAA passages is taken as a measure for the amount of induced radioactivity. A Neural Network Model is used …

Comptel All-Sky Imaging At 2.2 Mev, Mark L. Mcconnell, S Fletcher, K Bennett, H Bloemen, R Diehl, W Hermsen, James M. Ryan, V Schonfelder, A W. Strong, R Vandijk

Space Science Center

It is now generally accepted that accretion of matter onto a compact object (white dwarf, neutron star or black hole) is one of the most efficient processes in the universe for producing high energy radiations. Measurements of the γ-ray emission will provide a potentially valuable means for furthering our understanding of the accretion process. Here we focus on neutroncapture processes, which can be expected in any situation where energetic neutrons may be produced and where the liberated neutrons will interact with matter before they decay (where they have a chance of undergoing some type of neutron capture). Line emission at …

Diffuse Galactic Continuum Emission: Recent Studies Using Comptel Data, A W. Strong, R Diehl, V Schonfelder, K Bennett, Mark L. Mcconnell, James M. Ryan

Space Science Center

COMPTEL full sky maximum entropy maps using 5 years of data have been produced using background estimates based on high-latitude observations. The Galactic diffuse emission can be studied using latitude and longitude profiles from these maps. Direct comparison of profiles with theoretical models is illustrated for the 10–30 MeV range. We demonstrate the presence of a broad latitude component, consistent with results from model-fitting studies. The method is also used to obtain model-independent broad-band spectra of the Galactic emission.

The Prompt Cosmic-Ray-Induced Background In The Orbiting Compton Telescope Comptel, James M. Ryan, S C. Kappadath, Mark L. Mcconnell, D Morris, V Schonfelder, M Varendorff, G Weidenspointer, W Hermsen, K Bennett

Space Science Center

The authors report the spectrum of background events that the COMPTEL instrument on ComptonGamma Ray Observatory experiences due to the instantaneous effects of cosmic rays. Otherbackgrounds are present in the data of this Compton telescope, but the components that closely follow the instantaneous flux of cosmic rays are the most identifiable. The background varies approximately linearly with the cosmic-ray intensity and exhibits a broad feature from about 1 to 10 MeV suggestive of the nuclear nature of the events. Above 10 MeV there is a marked change in the nature of thebackground that is not understood. It appears that the …

Evidence For Γ-Ray Flares In 3c 279 And Pks 1622-297 At ∼10 Mev, W Collmar, V Schonfelder, H Bloemen, J J. Blom, W Hermsen, Mark L. Mcconnell, J G. Stacy, K Bennett, O R. Williams

Space Science Center

The EGRET experiment aboard the Compton Gamma-Ray Observatory (CGRO) has observed at energies above 100 MeV strong gamma-ray flares with short-term time variability from thegamma-ray blazars 3C 279 [1] and PKS 1622-297 [2]. During these flaring periods both blazarshave been detected by the COMPTEL experiment aboard CGRO at photon energies of ∼10 MeV, revealing simultaneous γ-ray activity down to these energies. For both cases the derived fluxes exceed those measured in previous observations, and 3C 279 shows an indication for time variability within the observational period. Both sources show evidence for ‘hard’ MeV spectra. In general the behaviour of both …

Improved Comptel 10–30 Mev Event Selections For Point Sources From Inflight Data, W Collmar, U Wessolowski, V Schonfelder, G Weidenspointer, S C. Kappadath, Mark L. Mcconnell, K Bennett

Space Science Center

After several years in orbit the COMPTEL experiment aboard the COMPTON Gamma-RayObservatory has collected a substantial amount of data from the MeV sky. We have used the inflight event data collected from the Crab, which is the brightest point source at MeV energies, to optimize our event selections for point sources. For the COMPTEL 10–30 MeV range we have derived a set of improved parameter selections, which leads to a reduction of background events and—at the same time—increases the number of source events, resulting in an obvious improvement in the signal-to-background ratio for point sources. Due to a revised cut …

Faculty Excellence, University Of New Hampshire

Faculty Excellence Awards

Each year, the University of New Hampshire selects a small number of its outstanding faculty for special recognition of their achievements in teaching, scholarship and service. Awards for Excellence in Teaching are given in each college and school, and university-wide awards recognize public service, research, teaching and engagement. This booklet details the year's award winners' accomplishments in short profiles with photographs and text.

Judging Contingencies Accurately: The Effects Of Feedback, Practice, And Self-Efficacy, Steven C. Clark

Doctoral Dissertations

Some psychologists have claimed that people are not good at judging covariation (e.g., Smedslund, 1963; Jenkins & Ward, 1965). This claim, however, has been based on the results of experiments that may not have been optimal for promoting judgmental accuracy (Allan & Jenkins, 1980). Other psychologists have claimed that people are relatively good judges of covariation (e.g., Wasserman, Chatlosh, & Neunaber, 1983; Wasserman & Shaklee, 1984). Common to most of this research is an experimental paradigm in which participants do not ever receive feedback concerning the accuracy of their judgments.

The two experiments in this dissertation were designed to promote …

Dynamic Response Of Poroelastic Materials Containing Bingham Fluid: Application To Electrorheological Fluids, Mete Kesan

Doctoral Dissertations

This work examines the dynamic response to harmonic loading of a disk of poroelastic material containing non-Newtonian Bingham fluid which exhibits a yield stress. Biot's poroelasticity equations and modified Darcy's law for non-Newtonian fluids exhibiting a yield stress are combined together to obtain the governing equations of the system for quasi-static case. Dissipation due to friction arising from the flow of fluid relative to the solid is taken into account but inertia effects are neglected. The response and the complex modulus of the system are calculated using the finite element method taking into account the nonlinear nature of Bingham fluid. …

Student Achievement, Parental Effort And Schooling, Andrew James Houtenville

Doctoral Dissertations

When evaluating public education programs that are aimed at improving student achievement, it is often assumed that a child's family background is an exogenous factor, albeit an important factor. However, parental decisions may be influenced by such programs. It is the assertion of Becker and Tomes (1976) that distortions in parental behavior (time allocation) may be one of the reasons that compensatory education fails to improve student achievement. In short, parents reduce their own effort when school services (schooling) is increased. However, theoretically parental responses are ambiguous; parental effort can increase or decrease in response to increased schooling. This dissertation …

A Sensory-Based Adaptive Walking Control Algorithm For Variable Speed Biped Robot Gaits, Andrew L. Kun

Doctoral Dissertations

A balance scheme for handling variable speed gaits was implemented on an experimental biped. The control scheme used pre-planned but adaptive motion sequences in combination with closed loop reactive control. CMAC neural networks were responsible for the adaptive control of side-to-side and front-to-back balance. The biped performance improved with neural network training. The biped was able to walk with variable speed gaits, and to change gait speeds on the fly. The slower gait speeds required statically balanced walking, while the faster speeds required dynamically balanced walking. It was not necessary to distinguish between the two balance modes within the controller. …

Contributions To The Theory Of Neighborhoods And Its Applications, Michael Joseph Cullinane

Doctoral Dissertations

Neighborhoods have played a fundamental role in general topology since the birth of the field. This work outlines the historial evolution of the notion of neighborhood and employs neighborhood assignments, weak neighborhood assignments, and a naturally induced notion of duality in a study of non-Hausdorff topological spaces. Neighborhood characterizations of various classes of spaces, among them the developable and the pseudometrizable spaces, are obtained. A generalization of topological spaces based upon a primitive notion of neighborhood is explored and examples are supplied to motivate the investigation.

Adaptive Multiresolution Visualization Of Large Multidimensional Multivariate Scientific Datasets, Pak Chung Wong

Doctoral Dissertations

The sizes of today's scientific datasets range from megabytes to terabytes, making it impossible to directly browse the raw datasets visually. This presents significant challenges for visualization scientists who are interested in supporting these datasets. In this thesis, we present an adaptive data representation model which can be utilized with many of the commonly employed visualization techniques when dealing with large amounts of data. Our hierarchical design also alleviates the long standing visualization problem due to limited display space. The idea is based on using compactly supported orthogonal wavelets and additional downsizing techniques to generate a hierarchy of fine to …

Perfect Matchings: Modified Aztec Diamonds, Covering Graphs Andn-Matchings, Adriana Badauta Cransac

Doctoral Dissertations

In the Introduction, we present the problems we are going to study and we establish the basic definitions, concepts and results that are used throughout.

We begin the first chapter with a presentation of the Aztec diamond and the behaviour of its random domino tilings. We introduce the dual-matching-problem and we explore the structure of the perfect matchings of modified Aztec diamonds. We show that some of these matchings can be extended to matchings of the dual Aztec diamond, pointing out a bijection between these types of matchings. We determine the number of perfect matchings for each of the modified …

Modeling Of The Electromagnetic Radiation From Shielded Enclosures With Apertures And Attached Wires In A Real-World Environment, Bruce Roy Archambeault

Doctoral Dissertations

A hybrid modeling technique using the Finite-Difference Time-Domain (FDTD) approach in conjunction with the Method of Moments (MoM) approach was developed to allow simulation of electromagnetic interference (EMI) emissions through apertures due to sources within a shielded enclosure. These apertures can include air ventilation openings, option card slots, mating cover seams, or any other opening in the metal shielded enclosure. Modeled emission results can now be directly compared to U.S. and other countries' regulations to allow engineers to predict compliance before hardware prototypes are built. The effects of the test environment, including ground plane and specified measurement distance, as well …

Contributions To The Theory Of Distance Functions And Its Application In General Topology, Lawrence Valery Neveu

Doctoral Dissertations

As non-Hausdorff spaces are becoming more important in topology, there is a need to consider new notions in topology to supplement the usual structures. This work uses distance functions to find useful generalizations (in a non-Hausdorff context) of the classes of spaces that are important in the Hausdorff setting. We begin, in the first part, with a historical overview that traces the evolution of the notion of distance and its role in the development of general topology.

In the second part of this work, we launch our study of distance functions. Using non-symmetric distance functions, called asymmetric, we generalize the …

Numerical Analysis For Blood Distribution In Complete Flow Cross-Section Microvascular Networks, Jewen Xiao

Doctoral Dissertations

As the blood flows through a bifurcation, the axisymmetric red blood cell concentration profile is skewed by plasma skimming. In the downstream segment of the bifurcation the concentration profile of red blood cells recovers symmetry by the red blood cell dispersion process.

In this study, the concentration convective equation, which models the red blood cell dispersion process, is solved with the method of finite differences in cylindrical coordinates. In the computation, a shear-induced diffusivity coefficient is used. The computed hematocrit ratios at the second bifurcation are compared with in vitro experimental data obtained from 50 $\mu$m serial trees with two …

Student Interactions And Mathematics Discourse: A Study Of The Development Of Discussions In A Fifth-Grade Classroom, Sharon Marie Soucy Mccrone

Doctoral Dissertations

Mathematics reform efforts are gaining attention and support in the years since the dissemination of the National Council of Teachers of Mathematics (NCTM) Standards documents. Encouraging student interactions in small and large group settings, and promoting discussion and argumentation of mathematical ideas among students are two possible implications of the vision presented in the Standards. The goal of having mathematics discussions, however, can present a variety of classroom challenges. Many factors influence classroom discourse and need to be addressed in ways that inform teachers as they work toward creating a more interactive, discussion-based mathematics classroom.

The study examines the development …

Relativistic Thinking And Identity Development In College Students, Rebecca Anne Regeth

Doctoral Dissertations

The relationship between relativistic thinking and identity formation was examined. Relativistic thinking is the ability to accept the subjective nature of knowledge and values and has been shown to develop during college. It was predicted that as students become more relativistic in their thinking, they also realize that their own perception of reality is relative too. This causes an identity crisis, resulting in a mature identity. A one-year longitudinal study showed that changes in identity (increased moratorium) were related to changes in thinking (increased relativism). Students in different college majors were shown to think differently about the nature of knowledge …

Response Of Outer Radiation Belt Electrons To A Magnetic Storm, Donald Hugh Brautigam

Doctoral Dissertations

To advance our understanding of the magnetic storm dynamics of the outer radiation belt relativistic electrons, the magnetic storm which commenced on 9 October 1990 was analyzed in detail using data from the Combined Release and Radiation Effects Satellite (CRRES) and the Los Alamos National Laboratory geosynchronous satellite 1989enspace 046. Electron differential flux was transformed into phase space density as a function of the three adiabatic invariants. The invariants were determined by magnetic field data from CRRES and the Tsyganenko 1989 Kp driven model. The unique work of this thesis is the storm time radial diffusion modeling performed using time …

Preparing The Way Of The Lord: Three Case Studies Of Ministerial Preconditioning In Congregations Before The Great Awakening, 1675-1750, Douglas Kevin Fidler

Doctoral Dissertations

This study demonstrates that ministerial predecessors in three northern New England communities actually preconditioned community reactions to the Great Awakening during the years preceding the revival itself. "Preconditioning" is not the ordinary "influence" of pastors within their churches and professional circles suggested in other works. This kind of influence might cause parishioners to consider various behavioral alternatives when confronted by spiritual circumstances. Preconditioned congregations would already have established paradigms for responding to spiritual stimulus. While individual parishioners might act in ways consistent with their own personalities, psychological needs, and spiritual sensitivities, congregations as a whole would apply a predetermined set …

On Some Range Inclusions, Mihaela Anca Poplicher

Doctoral Dissertations

The de Branges-Rovnyak spaces have been introduced by Louis de Branges and James Rovnyak, and have been studied by several authors, in particular by Donald Sarason. The object of this thesis is to study more extensively some properties of this class of spaces. In particular, which of these spaces are invariant under the action of which composition operators, or adjoints of composition operators.

Some known facts and a couple of new properties are included in Chapter 1. There it is shown that the norm of the kernel function for evaluation at a point in the unit disc (in the de …

The Use Of An Artificial Light System To Assess The Influence Of Relative Light Change On Diel Activity Cycles Of Nymphs Of The Mayfly, Stenonema Modestum, In The Presence And Absence Of Predators, Annette L. Schloss

Doctoral Dissertations

A mechanism by which light controls diel changes in locomotor activity and surface location of mayfly nymphs (Stenonema modestum Banks), named the Stimulus-based Timing and Activity-Rate (STAR) Model, was tested. Nymph movements were video-recorded in time-lapse from underneath unglazed artificial substrates in a laboratory stream. Light/dark cycles were simulated using computer-controlled halogen lamps. Light increases and decreases were generated to maintain constant rates of relative light change throughout simulated twilight periods. Nymph locomotor activity and position on the substrate were measured in response to rate of light change. Experiments tested whether adaptation light intensity (10$\sp{-4}$ or 10$\sp{-6}$ W cm$\sp{-2}$), time …

Ecological Database Development And Analyses Of Soil Variability In Northern New England, Michael Anayo Okoye

Doctoral Dissertations

The 1983 Forest Inventory and Analysis (FIA) data of the states of Maine, New Hampshire and Vermont (the study area) contain large amounts of field-measurements of many ecologically important variables. Despite the vast potential usefulness of the FIA data for scientific research, the data were until now, literally unused except for a few administrative purposes, because of problems in the way the data were organized, summarized, and coded for storage. The primary objective of this research was to solve the problems that had thus precluded these FIA data from use in scientific applications, and present the data in a form …

A Metric-Based Scientific Data Model For Knowledge Discovery, David T. Kao

Doctoral Dissertations

Scientific data, which include multimedia (e.g., images, audio, and video) and non-standard data (e.g., finger prints and DNA sequences), is characterized by rich and complex inter-instance relationships in addition to the inter-entity relationships found in traditional data. Conventional data models are insufficient for modeling such inter-instance relationships. This thesis proposes a metric-based scientific data model from the notions of data-as-functions and pseudo-quasimetrics, which are used to model inter-entity and inter-instance relationships respectively. Compared to other scientific data models, the metric-based conceptual model can be applied to many data sets where geometric views might not otherwise be available.

A detailed approach …

Annual Report Of The Officers Of The Town Of Plymouth, N.H. Year Ending December 31, 1996 Fiscal Year Ending June 30, 1996., Plymouth Town Representatives

Plymouth, NH Annual Reports

This is an annual report containing vital statistics for a town/city in the state of New Hampshire.

Annual Report Of The Officers Of The Town Of Center Harbor For The Fiscal Year Ending December 31, 1996., Center Harbor Town Representatives

Center Harbor, NH Annual Reports

This is an annual report containing vital statistics for a town/city in the state of New Hampshire.

Annual Report Of The Town Officers Of The Town Of Clarksville, New Hampshire, For The Year Ending December 31, 1996, Including Report Of The School Directors., Clarksville Town Representatives

Clarksville, NH Annual Reports

This is an annual report containing vital statistics for a town/city in the state of New Hampshire.

Table Of Contents Volume Eight, Number One, Winter 1997, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal RISK: Health, Safety & Environment (ISSN: 1073-8673)