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University of New Hampshire

1997

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Articles 1 - 30 of 59

Full-Text Articles in Physical Sciences and Mathematics

Distributions Of Beryllium 7 And Lead 2109, And Soluble Aerosol-Associated Ionic Species Over The Western Pacific: Pem West B, February-March 1994, Jack E. Dibb, R. Talbot, Barry Lefer, Eric Scheuer, G L. Gregory, E V. Browell, J D. Bradshaw, S T. Sandholm, H B. Singh Dec 1997

Distributions Of Beryllium 7 And Lead 2109, And Soluble Aerosol-Associated Ionic Species Over The Western Pacific: Pem West B, February-March 1994, Jack E. Dibb, R. Talbot, Barry Lefer, Eric Scheuer, G L. Gregory, E V. Browell, J D. Bradshaw, S T. Sandholm, H B. Singh

Earth Sciences

Aerosol sampling for the determination of the concentrations of soluble ionic species and the natural radionuclides 7Be and 210Pb was conducted from the NASA DC-8 over the western Pacific as part of GTE/PEM-West B during February-March 1994. Concentrations of most soluble ionic species in the free troposphere were higher in samples collected on flights originating from Hong Kong and Japan than those collected further east over the open ocean. In both regions the measured concentrations were higher than those found during PEM-West A (fall 1991). Activities of 210Pb, a tracer of air masses influenced by sources on …

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Chemical Characteristics Of Continental Outflow From Asia To The Troposphere Over The Western Pacific Ocean During February-March 1994: Results From Pem-West B, R. Talbot, Jack E. Dibb, Barry Lefer, J D. Bradshaw, S T. Sandholm, D R. Blake, N J. Blake, G W. Sachse, J E. Collins Jr, B J. Heikes, J T. Merrill, G L. Gregory, B E. Anderson, H B. Singh, D C. Thornton, A R. Bandy, R F. Pueschel Dec 1997

Chemical Characteristics Of Continental Outflow From Asia To The Troposphere Over The Western Pacific Ocean During February-March 1994: Results From Pem-West B, R. Talbot, Jack E. Dibb, Barry Lefer, J D. Bradshaw, S T. Sandholm, D R. Blake, N J. Blake, G W. Sachse, J E. Collins Jr, B J. Heikes, J T. Merrill, G L. Gregory, B E. Anderson, H B. Singh, D C. Thornton, A R. Bandy, R F. Pueschel

Earth Sciences

We present here the chemical composition of outflow from the Asian continent to the atmosphere over the western Pacific basin during the Pacific Exploratory Mission-West (PEM-West B) in February–March 1994. Comprehensive measurements of important tropospheric trace gases and aerosol particulate matter were performed from the NASA DC-8 airborne laboratory. Backward 5 day isentropic trajectories were used to partition the outflow from two major source regions: continental north (>20°N) and continental south (<20°N). Air parcels that had not passed over continental areas for the previous 5 days were classified as originating from an aged marine source. The trajectories and the chemistry together indicated that there was extensive rapid outflow of air parcels at altitudes below 5 km, while aged marine air was rarely encountered and only at <20°N latitude. The outflow at low altitudes had enhancements in common industrial solvent vapors such as C2Cl4, CH3CCl3, and C6H6, intermixed with the combustion emission products C2H2, C …

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Comparisons Of Trace Constituents From Ground Stations And The Dc-8 Aircraft During Pem-West B, Richard Arimoto, R A. Duce, J M. Prospero, D L. Savoie, R. Talbot, Jack E. Dibb, B J. Heikes, B J. Ray, N F. Lewis, U Tomza Dec 1997

Comparisons Of Trace Constituents From Ground Stations And The Dc-8 Aircraft During Pem-West B, Richard Arimoto, R A. Duce, J M. Prospero, D L. Savoie, R. Talbot, Jack E. Dibb, B J. Heikes, B J. Ray, N F. Lewis, U Tomza

Earth Sciences

Chemical data from ground stations in Asia and the North Pacific are compared with data from the DC-8 aircraft collected during the Pacific Exploratory Measurements in the Western Pacific Ocean (PEM-West B) mission. Ground station sampling took place on Hong Kong, Taiwan, Okinawa, and Cheju; and at three Pacific islands, Shemya, Midway, and Oahu. Aircraft samples were collected during 19 flights, most over the western North Pacific. Aluminum was used as an indicator of mineral aerosol, and even though the aircraft did sample Asian dust, strong dust storms were not encountered. The frequency distribution for non-sea-salt sulfate (nss SO4 …

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Large-Scale Distributions Of Tropospheric Nitric, Formic, And Acetic Acids Over The Western Pacific Basin During Wintertime, R. Talbot, Jack E. Dibb, Barry Lefer, Eric Scheuer, J D. Bradshaw, S T. Sandholm, S Smyth, D R. Blake, N J. Blake, G W. Sachse, J E. Collins Jr, G L. Gregory Dec 1997

Large-Scale Distributions Of Tropospheric Nitric, Formic, And Acetic Acids Over The Western Pacific Basin During Wintertime, R. Talbot, Jack E. Dibb, Barry Lefer, Eric Scheuer, J D. Bradshaw, S T. Sandholm, S Smyth, D R. Blake, N J. Blake, G W. Sachse, J E. Collins Jr, G L. Gregory

Earth Sciences

We report here measurements of the acidic gases nitric (HNO3), formic (HCOOH), and acetic (CH3COOH) over the western Pacific basin during the February-March 1994 Pacific Exploratory Mission-West (PEM-West B). These data were obtained aboard the NASA DC-8 research aircraft as it flew missions in the altitude range of 0.3–12.5 km over equatorial regions near Guam and then further westward encompassing the entire Pacific Rim arc. Aged marine air over the equatorial Pacific generally exhibited mixing ratios of acidic gases <100 parts per trillion by volume (pptv). Near the Asian continent, discrete plumes encountered below 6 km altitude contained up to 8 parts per billion by volume (ppbv) HNO3 and 10 ppbv HCOOH and CH3COOH. Overall there was a general correlation between mixing …

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Transport Of Sulfur Dioxide From The Asian Pacific Rim To The North Pacific Troposphere, D C. Thornton, A R. Bandy, Byrin W. Blomquist, R. Talbot, Jack E. Dibb Dec 1997

Transport Of Sulfur Dioxide From The Asian Pacific Rim To The North Pacific Troposphere, D C. Thornton, A R. Bandy, Byrin W. Blomquist, R. Talbot, Jack E. Dibb

Earth Sciences

The NASA Pacific Exploratory Mission over the Western Pacific Ocean (PEM-West B) field experiment provided an opportunity to study sulfur dioxide (SO2) in the troposphere over the western Pacific Ocean from the tropics to 60°N during February–March 1993. The large suite of chemical and physical measurements yielded a complex matrix in which to understand the distribution of sulfur dioxide over the western Pacific region. In contrast to the late summer period of Pacific Exploratory Mission-West A (PEM-West A) (1991) over this same area, SO2showed little increase with altitude, and concentrations were much lower in the free …

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Global Energetic Neutral Atom (Ena) Measurements And Their Association With The Dst Index, A. M. Jorgensen, Harlan E. Spence, M. G. Henderson, G. D. Reeves, M. Sugiura, T. Kamei Dec 1997

Global Energetic Neutral Atom (Ena) Measurements And Their Association With The Dst Index, A. M. Jorgensen, Harlan E. Spence, M. G. Henderson, G. D. Reeves, M. Sugiura, T. Kamei

Physics & Astronomy

We present a new global magnetospheric index that measures the intensity of the Earth's ring current through energetic neutral atoms (ENAs). We have named it the Global Energetic Neutral Index (GENI), and it is derived from ENA measurements obtained by the Imaging Proton Spectrometer (IPS), part of the Comprehensive Energetic Particle and Pitch Angle Distribution (CEPPAD) experiment on the POLAR satellite. GENI provides a simple orbit-independent global sum of ENAs measured with IPS. Actual ENA measurements for the same magnetospheric state look different when seen from different points in the POLAR orbit. In addition, the instrument is sensitive …

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Layout For Visualizing Large Software Structures In 3d, Colin Ware, Glenn Franck, Monica Parkhi, Tim Dudley Dec 1997

Layout For Visualizing Large Software Structures In 3d, Colin Ware, Glenn Franck, Monica Parkhi, Tim Dudley

Center for Coastal and Ocean Mapping

There is increasing evidence that 3D visualization of complex structures has advantages over 2D visualization. While nested directed graphs are an important method of representing information in 2D or 3D, they must be effectively organized in order to be understood. Most work on graph layout has assumed that fully automatic layout is desirable. Through our work with graphs representing large software structures, we have found that, due to the importance of the semantic content, it is necessary to combine automatic layout with manual layout. This paper describes a system called GraphVisualizer3D, which was designed to help people understand large nested …

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Assessment Of The Record Of The 1982 El Chichón Eruption As Preserved In Greenland Snow, Gregory A. Zielinski, Jack E. Dibb, Qinzhao Yang, Paul A. Mayewski, Sallie I. Whitlow, Mark S. Twickler, Mark S. Germani Dec 1997

Assessment Of The Record Of The 1982 El Chichón Eruption As Preserved In Greenland Snow, Gregory A. Zielinski, Jack E. Dibb, Qinzhao Yang, Paul A. Mayewski, Sallie I. Whitlow, Mark S. Twickler, Mark S. Germani

Earth Sciences

Variability in the SO4 2- and Cl- time series for the 1980s from 12 shallow snow pits across the Greenland ice sheet is used to evaluate the record of the 1982 El Chichón eruption and the potential for recording a moderate northern equatorial eruption in a single Greenland ice core. Composition of volcanic glass found in spring 1983 snow in one of the pits in the Summit region matches that from El Chichón glass, thereby verifying the deposition of material from the eruption. High Na+ and Cl- concentrations in this same layer probably represent deposition of the reaction products of …

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Temporal And Spatial Variability Of Snow Accumulation In Central Greenland, H Kuhns, C Davidson, Jack E. Dibb, C Stearns, M H. Bergin, J L. Jaffrezo Dec 1997

Temporal And Spatial Variability Of Snow Accumulation In Central Greenland, H Kuhns, C Davidson, Jack E. Dibb, C Stearns, M H. Bergin, J L. Jaffrezo

Earth Sciences

Snow accumulation records from central Greenland are explored to improve the understanding of the accumulation signal in Greenland ice core records. Results from a “forest” of 100 bamboo poles and automated accumulation monitors in the vicinity of Summit as well as shallow cores collected in the Summit and Crete areas are presented. Based on these accumulation data, a regression has been calculated to quantify the signal-to-noise variance ratio of ice core accumulation signals on a variety of temporal (1 week to 2 years) and spatial (20 m to 200 km) scales. Results are consistent with data obtained from year-round automated …

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Air-Snow Exchange Investigations At Summit, Greenland: An Overview, Jack E. Dibb, J L. Jaffrezo Nov 1997

Air-Snow Exchange Investigations At Summit, Greenland: An Overview, Jack E. Dibb, J L. Jaffrezo

Earth Sciences

The Greenland Ice Sheet Project 2 (GISP2) and Greenland Ice Core Project (GRIP) deep drilling programs at Summit, Greenland included support (both logistical and scientific) of extensive investigation of atmospheric transport and air-snow exchange processes of gases and particles relevant to the interpretation of the ice-core records. Much of the sampling for the air-snow exchange investigations was conducted at a unique solar-powered camp 30 km southwest of the GISP2 drill camp (even further from the GRIP camp) and was characterized by a high degree of international collaboration and cooperation. The wide range of expertise and analytical capabilities of the 20-plus …

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Prototype For Sontrac: A Scintillating Plastic Fiber Detector For Solar Neutron Spectroscopy, James M. Ryan, Janis Baltgalvis, D Holslin, John R. Macri, Mark L. Mcconnell, Cornelia B. Wunderer, Aaron R. Polichar Oct 1997

Prototype For Sontrac: A Scintillating Plastic Fiber Detector For Solar Neutron Spectroscopy, James M. Ryan, Janis Baltgalvis, D Holslin, John R. Macri, Mark L. Mcconnell, Cornelia B. Wunderer, Aaron R. Polichar

Space Science Center

We report the scientific motivation for and performance measurements of a prototype detector system for SONTRAC, a solar neutron tracking experiment designed to study high- energy solar flare processes. The full SONTRAC instrument will measure the energy and direction of 20 to 200 MeV neutrons by imaging the ionization tracks of the recoil protons in a densely packed bundle of scintillating plastic fibers. The prototype detector consists of a 12.7 mm square bundle of 250 micrometer scintillating plastic fibers, 10 cm long. A photomultiplier detects scintillation light from one end of the fiber bundle and provides a detection trigger to …

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A Prototype For Sontrac, A Scintillating Plastic Fiber Tracking Detector For Neutron Imaging And Spectroscopy, James M. Ryan, John R. Macri, Mark L. Mcconnell, C B. Wunderer, D Holslin, Aaron R. Polichar, Janis Baltgalvis Oct 1997

A Prototype For Sontrac, A Scintillating Plastic Fiber Tracking Detector For Neutron Imaging And Spectroscopy, James M. Ryan, John R. Macri, Mark L. Mcconnell, C B. Wunderer, D Holslin, Aaron R. Polichar, Janis Baltgalvis

Space Science Center

We report on tests of a prototype detector system designed to perform imaging and spectroscopy on 20 to 250 MeV neutrons. Although developed for the study of high-energy solar flare processes, the detection techniques employed for SONTRAC, the SOlar Neutron TRACking experiment, can be applied to measurements in a variety of disciplines including atmospheric physics, radiation therapy and nuclear materials monitoring. The SONTRAC instrument measures the energy and direction ofneutrons by detecting double neutron-proton scatters and recording images of the ionization tracks of the recoil protons in a densely packed bundle of scintillating plastic fibers stacked in orthogonal layers. By …

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Is Accurate Understanding Of Global Warming Necessary To Promote Willingness To Sacrifice?, Richard J. Bord, Ann Fisher, Robert E. O'Connor Sep 1997

Is Accurate Understanding Of Global Warming Necessary To Promote Willingness To Sacrifice?, Richard J. Bord, Ann Fisher, Robert E. O'Connor

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

Although not definitive, the authors' study suggests potential benefits from having a general public better informed about global climate change. They find, e.g., that accurate information appears to increase willingness to accept personal sacrifice.

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Book Review Of Deborah G. Mayo, Error And The Growth Of Experimental Knowledge (University Of Chicago Press 1996), Kristin S. Shrader-Frechette Sep 1997

Book Review Of Deborah G. Mayo, Error And The Growth Of Experimental Knowledge (University Of Chicago Press 1996), Kristin S. Shrader-Frechette

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

Review of the book: Deborah G. Mayo, Error and the Growth of Experimental Knowledge (University of Chicago Press 1996). Figures, index, preface, references. ISBN 0-226-51197-9 [493 pp. $74.00 Cloth; $29.95 Paper. 5801 S. Ellis Ave., Chicago, IL 60637.]

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Sontrac-A Low Background, Large Area Solar Neutron Spectrometer, C B. Wunderer, D Holslin, John R. Macri, Mark L. Mcconnell, James M. Ryan Jul 1997

Sontrac-A Low Background, Large Area Solar Neutron Spectrometer, C B. Wunderer, D Holslin, John R. Macri, Mark L. Mcconnell, James M. Ryan

Space Science Center

SONTRAC will measure 20-250 MeV neutrons from solar flares using scintillator fibers viewed by CCD cameras to track neutron-proton scatters. SONTRAC can also be used to track gamma rays above 20 MeV. Veto shields are used to reject all charged particles. Gamma-ray and neutron events have very different track densities, allowing discrimination between the two. Double neutron-proton scatters allow unambiguous determination of the incident neutron energy and direction. Therefore, SONTRAC is capable of rejecting almost all background except neutrons from the solar direction. SONTRAC would have detected the June 15, 1991 flare with 42σ for 20-100 MeV neutrons, having an …

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Activation In The Comptel Double-Scattering Gamma-Ray Telescope, D Morris, Mark L. Mcconnell, James M. Ryan, R Diehl, U Oberlack, V Schonfelder, M Varendorff, G Weidenspointer, H Deboer, K Bennett Jul 1997

Activation In The Comptel Double-Scattering Gamma-Ray Telescope, D Morris, Mark L. Mcconnell, James M. Ryan, R Diehl, U Oberlack, V Schonfelder, M Varendorff, G Weidenspointer, H Deboer, K Bennett

Space Science Center

Abstract-The COMPTEL gamma-ray telescope has been operating in low Earth orbit for six years, since the launch of the Compton Gamma-Ray Observatory in April 1991. Comparisons of data for different orbits and epochs show evidence of activation on time scales from minutes (27Mg, q,2=9.5 min) to years C2Na, q&.58 yr). The activation is correlated with both the orbital altitude and solar cosmic-ray modulation. Because it requires coincident measurements in two different detectors, COMPTEL is most susceptible to instrumental background events in which two or more photons are produced simultaneously.

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Initial Polar Mfe Observation Of Substorm Signatures In The Polar Magnetosphere, H. Kawano, G. Le, C. T. Russell, G. Rostoker, T. Mukai, Harlan E. Spence Jun 1997

Initial Polar Mfe Observation Of Substorm Signatures In The Polar Magnetosphere, H. Kawano, G. Le, C. T. Russell, G. Rostoker, T. Mukai, Harlan E. Spence

Physics & Astronomy

This paper studies substorm influences in the polar magnetosphere using data from the POLAR magnetic field experiment (MFE). The POLAR spacecraft remains in the high altitude polar magnetosphere for extended periods around apogee. There it can stay at nearly constant altitude through all phases of a substorm, which was not possible on previous missions. We report such an event on March 28, 1996. Ground magnetometers monitored substorm activity, while the POLAR spacecraft, directly over the pole at (−0.8, −0.6, 8.5) RE in GSM coordinates, observed a corresponding perturbation in the total magnetic field strength. The total magnetic field first …

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First Polar And 1995-034 Observations Of The Midaltitude Cusp During A Persistent Northward Imf Condition, M. Grande, J. Fennell, S. Livi, B. Kellett, C. Perry, P. Anderson, J. Roeder, Harlan E. Spence, T. Fritz, B. Wilken Jun 1997

First Polar And 1995-034 Observations Of The Midaltitude Cusp During A Persistent Northward Imf Condition, M. Grande, J. Fennell, S. Livi, B. Kellett, C. Perry, P. Anderson, J. Roeder, Harlan E. Spence, T. Fritz, B. Wilken

Physics & Astronomy

We present the first observations by Polar and 1995-034 of the mid-altitude cusp. On May 29, 1996, the Polar and 1995-034 spacecraft crossed into an extended cusp region. The region was characterized by intense fluxes of solar wind like ions in the energy range 1–10 keV that had angular distributions that showed evidence of flows and trapping. The ion composition data are combined with energetic proton observations from Polar and plasma observations from 1995-034 and DMSP satellites to examine the spatial and temporal extent and plasma characteristics of the cusp during a persistent northward IMF condition. The composition data is …

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A New, Temporarily Confined Population In The Polar Cap During The August 27, 1996 Geomagnetic Field Distortion Period, Jiasheng Chen, Theodore A. Fritz, Robert B. Sheldon, Harlan E. Spence, Walther N. Spjeldvik, Joseph F. Fennell, Stefano Livi Jun 1997

A New, Temporarily Confined Population In The Polar Cap During The August 27, 1996 Geomagnetic Field Distortion Period, Jiasheng Chen, Theodore A. Fritz, Robert B. Sheldon, Harlan E. Spence, Walther N. Spjeldvik, Joseph F. Fennell, Stefano Livi

Physics & Astronomy

On August 27, 1996, a two-hour energetic heavy ion event (∼1 MeV) was detected at 8:25 UT at apogee (∼9 Re and an invariant latitude of ∼80°), by the Charge and Mass Magnetospheric Ion Composition Experiment onboard POLAR. The event, with a maximum spin averaged peak flux of ∼150 particles/(cm²-sr-s-MeV), showed three local peaks corresponding to three localized regions; the ion pitch angle distributions in the three regions were different from an isotropic distribution and different from each other. No comparable flux was observed by the WIND spacecraft. The appearance of lower energy He++ and O > +2 during the event …

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Table Of Contents Volume Eight, Number Three, Summer 1997, Risk Editorial Board Jun 1997

Table Of Contents Volume Eight, Number Three, Summer 1997, Risk Editorial Board

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

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

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Scientific Facts Vs. Political Values, Thomas G. Field Jr. Jun 1997

Scientific Facts Vs. Political Values, Thomas G. Field Jr.

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

Professor Field takes exception to a recent Science editorial.

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An Administrative View Of Model Uncertainty In Public Health, Clark D. Carrington Jun 1997

An Administrative View Of Model Uncertainty In Public Health, Clark D. Carrington

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

Dr. Carrington reviews several ways to deal with model uncertainty, including those failing to acknowledge any use of models. He then evaluates six such methods with regard to, e.g., transparency and cost of execution.

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Reassessing The History Of U.S. Hazardous Waste Disposal Policy - Problem Definition, Expert Knowledge And Agenda-Setting, Halina Szejnwald Brown, Brian J. Cook, Robert Krueger, Shatkin Jun 1997

Reassessing The History Of U.S. Hazardous Waste Disposal Policy - Problem Definition, Expert Knowledge And Agenda-Setting, Halina Szejnwald Brown, Brian J. Cook, Robert Krueger, Shatkin

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

The authors show that in the 1940's technical consensus began to develop about the effects of land-based waste disposal on groundwater degradation. They go on to explain why this understanding was only slowly reflected in federal legislation.

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Strategy For Cost-Effective Reduction Of The Sum Of Health Risk Estimates For Exposures To Mixtures Of Toxic Substances, David W. Gaylor, James J. Chen Jun 1997

Strategy For Cost-Effective Reduction Of The Sum Of Health Risk Estimates For Exposures To Mixtures Of Toxic Substances, David W. Gaylor, James J. Chen

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

The authors argue that a minimization approach can provide guidance for effective use of funds to reduce the sum of estimated risks or the upper limit of the sum of risk estimates for mixtures of chemicals.

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Book Review Of Joshua M. Epstein & Robert Axtell, Growing Artificial Societies: Social Science From The Bottom Up (Mit Press 1996), Sean D. Detweiler Jun 1997

Book Review Of Joshua M. Epstein & Robert Axtell, Growing Artificial Societies: Social Science From The Bottom Up (Mit Press 1996), Sean D. Detweiler

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

Review of the book Joshua M. Epstein & Robert Axtell, Growing Artificial Societies: Social Science from the Bottom Up (MIT Press 1996). Acknowledgements, appendices, index, introduction references. LC 96-25332; ISBN 0-262-05053-6. [208 pp. Cloth $39.95. 55 Hayward St., Cambridge MA 02142.]

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First Energetic Neutral Atom Images From Polar, M. G. Henderson, G. D. Reeves, Harlan E. Spence, R. B. Sheldon, A. M. Jorgensen, J. B. Blake, J. F. Fennell May 1997

First Energetic Neutral Atom Images From Polar, M. G. Henderson, G. D. Reeves, Harlan E. Spence, R. B. Sheldon, A. M. Jorgensen, J. B. Blake, J. F. Fennell

Physics & Astronomy

Energetic neutral atoms are created when energetic magnetospheric ions undergo charge exchange with cold neutral atoms in the Earth's tenuous extended atmosphere (the geocorona). Since they are unaffected by the Earth's magnetic field, these energetic neutrals travel away in straight line trajectories from the points of charge exchange. The remote detection of these particles provides a powerful means through which the global distribution and properties of the geocorona and ring current can be inferred. Due to its 2 × 9 RE polar orbit, the Polar spacecraft provides an excellent platform from which to observe ENAs because it spends much of …

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Cdznte Strip Detectors As Sub-Millimeter Resolution Imaging Gamma Radiation Spectrometers, K Larson, V Boykin, M L. Cherry, J F. Courville, F P. Doty, A Drake, T G. Guzik, L A. Hamel, John R. Macri, M Mayer, Mark L. Mcconnell, James M. Ryan, O Tousignant May 1997

Cdznte Strip Detectors As Sub-Millimeter Resolution Imaging Gamma Radiation Spectrometers, K Larson, V Boykin, M L. Cherry, J F. Courville, F P. Doty, A Drake, T G. Guzik, L A. Hamel, John R. Macri, M Mayer, Mark L. Mcconnell, James M. Ryan, O Tousignant

Space Science Center

We report γ-ray detection performance measurements and computer simulations of a sub-millimeter pitch CdZnTe strip detector. The detector is a prototype for γ-ray measurements in the range of 20-600 keV. The prototype is a 1.5 mm thick, 64×64 orthogonal stripe CdZnTe detector of 0.375 mm pitch in both dimensions, with approximately one square inch of sensitive area. Using discrete laboratory electronics to process signals from an 8×8 stripe region of the prototype we measured good spectroscopic uniformity and sub-pitch (~0.2 mm) spatial resolution in both x and y dimensions. We present below measurements of the spatial uniformity, relative timing and …

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Physical And Managed Risk Of Nuclear Waste, Lennart Sjöberg, Britt-Marie Drottz-Sjöberg Mar 1997

Physical And Managed Risk Of Nuclear Waste, Lennart Sjöberg, Britt-Marie Drottz-Sjöberg

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

The authors describe their work on the perceived risk of nuclear waste in Sweden. Three levels of waste were studied, and comparisons between the perceptions of the public, politicians and nuclear experts are made.

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Book Review Of Alla Yaroshinskaya, Chernobyl: The Forbidden Truth, John M. Gleason Mar 1997

Book Review Of Alla Yaroshinskaya, Chernobyl: The Forbidden Truth, John M. Gleason

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

Review of the book: Alla Yaroshinskaya, Chernobyl: The Forbidden Truth (Michele Kahn & Julia Sallabank, trans. University of Nebraska Press 1995). Introduction, foreword, list of illustrations, photographs. ISBN 0-8032-4912-8. [136 pp. Cloth $25.00; Paper $10.00. 312 N. 14th Street, Lincoln NE 68588-0484.]

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Table Of Contents Volume Eight, Number Two, Spring 1997, Risk Editorial Board Mar 1997

Table Of Contents Volume Eight, Number Two, Spring 1997, Risk Editorial Board

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

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

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