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New possibilities for a secure and just world (open access)

New possibilities for a secure and just world

More than a decade ago individuals from three significant institutions in East Bay Area began discussions in response to the apprehensions that were so deep in the early 1980s. These apprehensions were a result of the intense rhetoric between the two superpowers and the casual commentary about ``limited nuclear war.`` The discussions spoke to the mortal danger as well as to the profound moral question revolving around nuclear arms. The issuance of the US Bishops` Pastoral on War and Peace in 1983 gave the group focus and momentum. The Chancellor at the University of California at Berkeley, the President of the Graduate Theological Union (the consortium of theological schools in Berkeley), and the Director of the Lawrence Livermore National Laboratory (one of the chief designers of American nuclear arms) encouraged us to complete plans for a symposium. It was an era of activism. We chose, however, to serve the theme expressed by Albert Einstein, ``Peace cannot be kept by force, it can only be achieved by understanding.`` After a decade, all of us can commend the leadership of the three institutions and the individuals involved for their perseverance. Their commitments to the pursuit of peace and to the development of …
Date: February 28, 1994
Creator: Zagotta, W. E.
System: The UNT Digital Library
Sodium/nickel-chloride battery development (open access)

Sodium/nickel-chloride battery development

The performance of the Ni/NiCl{sub 2} positive electrode for the Na/NiCl{sub 2} battery has been significantly improved compared to that of our earlier electrodes, representative for 1990. This improvement has been achieved by lowering the impedance and increasing the usable capacity through the use of chemical additives and a tailored electrode morphology. The improved electrode has excellent performance even at 250{degrees}C and can be recharged within one hour. The performance of this new electrode was measured by the conventional interrupted galvanostatic method and under simulated driving profiles. These measurements were used to project the performance of 40- to 60-kWh batteries built with this new electrode combined with the already highly developed sodium/{beta}{double_prime}-alumina negative electrode. These calculated results yielded a specific power of 150--400 W/kg and a specific energy of 110--200 Wh/kg for batteries with single-tube and bipolar cell designs. This high performance, along with the high cell voltage, mid-temperature operation, fast recharge capability, and short-circuited failure mode of the electrode couple, makes the Na/NiCl{sub 2} battery attractive for electric vehicle applications.
Date: February 28, 1994
Creator: Redey, L.; Prakash, J.; Vissers, D. R. & Dowgiallo, E. J.
System: The UNT Digital Library
Selective Fluorescence Quenching to Discriminate Between Alternant and Non-alternant Polycyclic Aromatic Hydrocarbons: Acephenanthrylene Derivatives as Exceptions to the Nitromethane Quenching Rule (open access)

Selective Fluorescence Quenching to Discriminate Between Alternant and Non-alternant Polycyclic Aromatic Hydrocarbons: Acephenanthrylene Derivatives as Exceptions to the Nitromethane Quenching Rule

Article on selective fluorescence quenching to discriminate between alternant and non-alternant polycyclic aromatic hydrocarbons and acephenanthrylene derivatives as exceptions to the nitromethane quenching rule.
Date: February 24, 1994
Creator: Tucker, Sheryl A. (Sheryl Ann); Griffin, Jason M.; Acree, William E. (William Eugene); Mulder, Patrick P. J.; Lugtenburg, Johan & Cornelisse, Jan
System: The UNT Digital Library
CANDID: Comparison algorithm for navigating digital image databases (open access)

CANDID: Comparison algorithm for navigating digital image databases

In this paper, we propose a method for calculating the similarity between two digital images. A global signature describing the texture, shape, or color content is first computed for every image stored in a database, and a normalized distance between probability density functions of feature vectors is used to match signatures. This method can be used to retrieve images from a database that are similar to an example target image. This algorithm is applied to the problem of search and retrieval for database containing pulmonary CT imagery, and experimental results are provided.
Date: February 21, 1994
Creator: Kelly, P. M. & Cannon, T. M.
System: The UNT Digital Library
Coupling correction using closed orbit measurements (open access)

Coupling correction using closed orbit measurements

The authors describe a coupling correction scheme they have developed and used to successfully reduce the vertical emittance of the NSLS X-Ray ring by a factor of 6 to below 2 A. This gives a vertical to horizontal emittance ratio of less than 0.2%. They find the strengths of 17 skew quadrupoles to simultaneously minimize the vertical dispersion and the coupling. As a measure of coupling they utilize the shift in vertical closed orbit resulting from a change in strength of a horizontal steering magnet. Experimental measurements confirm the reduced emittance.
Date: February 18, 1994
Creator: Safranek, J. & Krinsky, S.
System: The UNT Digital Library
Stapp`S Quantum Dualism: The James/Heisenberg Model of Consciousness (open access)

Stapp`S Quantum Dualism: The James/Heisenberg Model of Consciousness

Henry Stapp attempts to resolve the Cartesian dilemma by introducing what the author would characterize as an ontological dualism between mind and matter. His model for mind comes from William James` description of conscious events and for matter from Werner Heisenberg`s ontological model for quantum events (wave function collapse). His demonstration of the isomorphism between the two types of events is successful, but in the author`s opinion fails to establish a monistic, scientific theory. The author traces Stapp`s failure to his adamant rejection of arbitrariness, or `randomness`. This makes it impossible for him (or for Bohr and Pauli before him) to understand the power of Darwin`s explanation of biology, let along the triumphs of modern `neo-Darwinism`. The author notes that the point at issue is a modern version of the unresolved opposition between Leucippus and Democritus on one side and Epicurus on the other. Stapp`s views are contrasted with recent discussions of consciousness by two eminent biologists: Crick and Edelman. They locate the problem firmly in the context of natural selection on the surface of the earth. Their approaches provide a sound basis for further scientific work. The author briefly examines the connection between this scientific (rather than ontological) framework …
Date: February 18, 1994
Creator: Noyes, H. P.
System: The UNT Digital Library
The Nijmegen hyperon-nucleon potentials (open access)

The Nijmegen hyperon-nucleon potentials

The Nijmegen YN potential models are reviewed. Differences with the models constructed by the Juelich group are highlighted. A mini- review is given of the status of the scalar mesons and their relevance for the NN and YN interactions. Finally, the reactions {bar N}N {yields} {bar Y}Y are discussed.
Date: February 17, 1994
Creator: Timmermans, R.
System: The UNT Digital Library
A spinor technique in symbolic Feynman diagram calculation mesons (open access)

A spinor technique in symbolic Feynman diagram calculation mesons

The authors present a recursive diagrammatic method for evaluating tree-level Feynman diagrams involving multi-fermions which interact through gauge bosons (gluons or photons). Based on this method, a package called COMPUTE, which can generate and calculate all the possible Feynman diagrams for exclusive processes in perturbative QCD, has been developed (available in both Mathematics and Maple). As an example, a calculation of the nucleon Compton scattering amplitude is given.
Date: February 17, 1994
Creator: Pang, A. & Ji, C.
System: The UNT Digital Library
The winds of cataclysmic variables (open access)

The winds of cataclysmic variables

The authors present an observational and theoretical review of the winds of cataclysmic variables (CVs). Specifically, they consider the related problems of the geometry and mass-loss rate of the winds of CVs, their ionization state and variability, and the results from studies of eclipsing CVs. Finally, they consider the properties of accretion disk wind models. Some of these models predict substantial angular momentum loss, which could affect both disk structure and binary evolution.
Date: February 16, 1994
Creator: Mauche, C. W. & Raymond, J. C.
System: The UNT Digital Library
A {open_quotes}New{close_quotes} regime for nuclear weapons and materials (open access)

A {open_quotes}New{close_quotes} regime for nuclear weapons and materials

In this paper, I discuss the principal ideas that I covered in my presentation on December 8, 1993, at the Future of Foreign Nuclear Materials Symposium held by the Naval Postgraduate School in Monterey, California. I was asked to discuss issues related to military inventories of plutonium, and I took this opportunity to describe a possible declaratory regime that could encompass military as well as civilian inventories of plutonium. The {open_quote}new{close_quotes} in the title does not imply that the regime discussed here is an original idea. Rather, the regime will be {open_quotes}new,{close_quotes} when it is adopted. The regime proposed here and in other works is one in which all stocks of nuclear weapons and materials are declared. Originally, declarations were proposed as a traditional arms control measure. Here, declarations are proposed to support the prevention of misuse of nuclear weapons and materials, including support for the nonproliferation regime. In the following, I discuss: (1) Worldwide inventories of nuclear weapons and materials, including the fact that military plutonium must be viewed as part of that worldwide inventory. (2) Life cycles of nuclear weapons and materials, including the various stages from the creation of nuclear materials for weapons through deployment and retirement …
Date: February 15, 1994
Creator: Sutcliffe, W. G.
System: The UNT Digital Library
Space sensors for global change (open access)

Space sensors for global change

Satellite measurements should contribute to a fuller understanding of the physical processes behind the radiation budget, exchange processes, and global change. Climate engineering requires global observation for early indications of predicted effects, which puts a premium on affordable, distributed constellations of satellites with effective, affordable sensors. Defense has a requirement for continuous global surveillance for warning of aggression, which could evolve from advanced sensors and satellites in development. Many climate engineering needs match those of defense technologies.
Date: February 15, 1994
Creator: Canavan, G. H.
System: The UNT Digital Library
Waste container fabrication from recycled DOE metal (open access)

Waste container fabrication from recycled DOE metal

The Department of Energy (DOE) has more than 2.5 million tons of radioactive scrap metal (RSM) that is either in inventory or expected to be generated over the next 25 years as major facilities within the weapons complex are decommissioned. Much of this material cannot be surface decontaminated. In an attempt to conserve natural resources and to avoid burial of this material at DOE disposal sites, options are now being explored to {open_quotes}beneficially reuse{close_quotes} this material in applications where small amounts of radioactivity are not a detriment. One example is where RSM is currently being beneficially used to fabricate shield blocks for use in DOE medium energy physics programs. This paper describes other initiatives now underway within DOE to utilize RSM to fabricate other products, such as radioactive waste shipping, storage and disposal containers.
Date: February 15, 1994
Creator: Motl, G. P. & Burns, D. D.
System: The UNT Digital Library
What can we do about it? (open access)

What can we do about it?

The requirements for intercept have been defined. Most can be met with existing technology. Them are significant uncertainties in coupling efficiency and fragmentation limits. The best approach depends on warning, NEO size and composition, and cost. Optimal defenses generally involve both detection and defense. They are effective to large diameters and justify expenditures on the order of $50-100M/yr. Flyby and landing precursor experiments are scientifically justified. Coupling and deflection experiments are also needed and feasible.
Date: February 15, 1994
Creator: Canavan, G. H.
System: The UNT Digital Library
Implications of ethanol-based fuels for greenhouse gas emissions (open access)

Implications of ethanol-based fuels for greenhouse gas emissions

The US Environmental Protection Agency has proposed a rule which would mandate that 30% of the oxygen content of reformulated gasoline be provided by renewable oxygenates. The rule would essentially require that biomass-based ethanol, or ETBE derived from ethanol, be used to supply 30% of the oxygen in reformulated gasoline. This short statement addresses the very narrow question, ``Would this rule result in a net decrease in greenhouse gas emissions?`` The challenge then is to determine how much greenhouse gas is emitted during the ethanol fuel cycle, a fuel cycle that is much less mature and less well documented than the petroleum fuel cycle. In the petroleum fuel cycle, most of the greenhouse gas emissions come from fuel combustion. In the ethanol fuel cycle most of the greenhouse gas emissions come from the fuel production processes. Details of corn productivity, fertilizer use, process efficiency, fuel source, etc. become very important. It is also important that the ethanol fuel cycle produces additional products and the greenhouse gas emissions have somehow to be allocated among the respective products. With so many variables in the ethanol fuel cycle, the concern is actually with ethanol-based additives which will be produced in response to the …
Date: February 14, 1994
Creator: Marland, G.; DeLuchi, M. A. & Wyman, C.
System: The UNT Digital Library
What is an open architecture robot controller? (open access)

What is an open architecture robot controller?

This paper addresses the issue of what is an open architecture robot controllers. Three different classifications are defined along with the various advantages and shortcomings of each approach. Knowledge from past research and new technology has been included in this analysis. The conclusions recommend a communication-based hybrid approach with well defined interfaces between modules.
Date: February 14, 1994
Creator: Ford, W.E.
System: The UNT Digital Library
The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste (open access)

The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste

On May 17, 1991, the US Department of Energy (DOE) issued a directive for DOE operations to cease off-site shipments of non-radioactive hazardous waste pending further clarification and approvals. A DOE Performance Objective for Certification of Non-Radioactive Hazardous Waste was issued in November 1991. In response to these directives, the Waste Management Division of Oak Ridge Y-12 Plant, with assistance from Roy F. Weston, Inc., has developed a No Rad-Added Program to provide small programmatic guidance and a set of procedures, approved by DOE, which will permit hazardous waste to be shipped from the Y-12 Plant to commercial treatment, storage, or disposal facilities after ensuring and certifying that hazardous waste has no radioactivity added as a result of DOE operations. There are serious legal and financial consequences of shipping waste containing radioactivity to an off-site facility not licensed to receive radioactive materials. Therefore, this program is designed with well-defined responsibilities and stringent documentation requirements.
Date: February 14, 1994
Creator: Cooper, K. H.; Mattie, B. K.; Williams, J. L.; Jacobs, D. G. & Roberts, K. A.
System: The UNT Digital Library
Deterrence, denuclearization, and proliferation: Alternative visions of the next fifty years (open access)

Deterrence, denuclearization, and proliferation: Alternative visions of the next fifty years

The great library of Alexandria may have contained fewer volumes than the number which have been written on the subject of nuclear weapons in the Cold War. With the end of the Cold War, a new nuclear library is in the making. Much thought is being given to the next steps in nuclear policy, strategy, forces, arms control, and nonproliferation. For this very distinguished conference, however, I have been asked to look further ahead indeed, forward fifty-years. Prognostication is always a risky business. Detailed predictions beyond the shortest duration are difficult to label as ``scientific`` even in the social sciences. Forecasting ahead fifty years in an age of ever accelerating change would seem to be hopeless. Projecting the future of nuclear weapons, however, may not be as complex as one might think. Detailing the future fifty years from now is not necessary. We want to inform upcoming decisions by examining the possibilities, not write a history in advance of what is to happen. Our look forward con benefit from a brief look back fifty years. In retrospect, those years passed quickly, and with each additional year, analysts make them appear more simple than they seemed at the time. This paper …
Date: February 12, 1994
Creator: Lehman, R. F., II
System: The UNT Digital Library
Vision Denton '94 (open access)

Vision Denton '94

Clippings from the Denton Record-Chronicle titled 'Vision Denton '94, City builds on education reputation'. The two clippings are part of the same story covering the collaboration of colleges including UNT, museums, and DFW Metroplex area schools. The collaboration offers better art programs and college credit to high schoolers.
Date: February 12, 1994
Creator: Cobler, Paula
System: The UNT Digital Library
Greenhouse gas emission impacts of electric vehicles under varying driving cycles in various counties and US cities (open access)

Greenhouse gas emission impacts of electric vehicles under varying driving cycles in various counties and US cities

Electric vehicles (EVs) can reduce greenhouse gas emissions, relative to emissions from gasoline-fueled vehicles. However, those studies have not considered all aspects that determine greenhouse gas emissions from both gasoline vehicles (GVs) and EVs. Aspects often overlooked include variations in vehicle trip characteristics, inclusion of all greenhouse gases, and vehicle total fuel cycle. In this paper, we estimate greenhouse gas emission reductions for EVs, including these important aspects. We select four US cities (Boston, Chicago, Los Angeles, and Washington, D.C.) and six countries (Australia, France, Japan, Norway, the United Kingdom, and the United States) and analyze greenhouse emission impacts of EVs in each city or country. We also select six driving cycles developed around the world (i.e., the US federal urban driving cycle, the Economic Community of Europe cycle 15, the Japanese 10-mode cycle, the Los Angeles 92 cycle, the New York City cycle, and the Sydney cycle). Note that we have not analyzed EVs in high-speed driving (e.g., highway driving), where the results would be less favorable to EVs; here, EVs are regarded as urban vehicles only. We choose one specific driving cycle for a given city or country and estimate the energy consumption of four-passenger compact electric and …
Date: February 10, 1994
Creator: Wang, M. Q. & Marr, W. W.
System: The UNT Digital Library
Neutron detectors for fusion reaction-rate measurements (open access)

Neutron detectors for fusion reaction-rate measurements

Fusion reactions in an inertial-confinement fusion (ICF) target filled with deuterium or a deuterium/tritium fuel release nearly monoenergetic neutrons. Because most the neutrons leave the compressed target without collision, they preserve reaction-rate information as they travel radially outward from their point of origin. Three fast, neutron detector techniques, each capable of measuring the fusion reaction-rate of ICF targets, have been demonstrated. The most advanced detector is based on the fast rise-time of a commercial plastic scintillator material (BC-422) which acts as a neutron-to-light converter. Signals, which are recorded with a fast optical streak camera, have a resolution of 25 ps. Good signals can be recorded for targets producing only 5 x 10{sup 7} DT neutrons. Two other detectors use knock-on collisions between neutrons and protons in a thin polyethylene (CH{sub 2}) converter. In one, the converter is placed in front of the photocathode of an x-ray streak camera. Recoil protons pass through the photocathode and knock out electrons which are accelerated and deflected to produce a signal. Resolutions < 25 ps are possible. In the other, the converter is placed in front of a microchannel plate (MCP) with a gated microstrip. Recoil protons eject electrons from the gold layer forming …
Date: February 10, 1994
Creator: Lerche, R. A.; Phillion, D. W.; Landen, O. L.; Murphy, T. J. & Jaanimagi, P. A.
System: The UNT Digital Library
ROOM: A recursive object oriented method for information systems development (open access)

ROOM: A recursive object oriented method for information systems development

Although complementary for the development of complex systems, top-down structured design and object oriented approach are still opposed and not integrated. As the complexity of the systems are still growing, and the so-called software crisis still not solved, it is urgent to provide a framework mixing the two paradigms. This paper presents an elegant attempt in this direction through our Recursive Object-Oriented Method (ROOM) in which a top-down approach divides the complexity of the system and an object oriented method studies a given level of abstraction. Illustrating this recursive schema with a simple example, we demonstrate that we achieve the goal of creating loosely coupled and reusable components.
Date: February 9, 1994
Creator: Thelliez, T. & Donahue, S.
System: The UNT Digital Library
Neutron diffraction from HoNi{sub 2}B{sub 2}C. Version 1 (open access)

Neutron diffraction from HoNi{sub 2}B{sub 2}C. Version 1

RENi{sub 2}B{sub 2}C (RE=Rare Earth) are quaternary compounds which exhibit a considerable degree of interaction between their superconducting and magnetic properties. The Ho variant is found to become superconducting at {Tc} = 9 K, but anomalous behaviour is observed in the low field magnetic properties at T<7 K (increasing susceptibility with decreasing temperature); at temperatures less than 5.6 K more conventional behaviour is regained. Neutron diffraction measurements demonstrate that at low temperatures (T<5K) the magnetic order consists of ferromagnetic planes antiferromagnetically coupled up the c-axis with a Ho moment of 8.9 {plus_minus}0 0.2 {mu}{sub B} canted at 15{degree}{plus_minus}5 from the a-b plane. At high temperatures (7<T<8.5 K) satellites, together with the principal Bragg reflections, are observed which correspond to a modulation of the magnetic order with a wavelength of {approximately} 136 {Angstrom} up the c-axis. In the intermediate temperature (5<T<7 K) range further Bragg refections become evident. An additional modulation along the a-axis becomes important in this temperature range.
Date: February 7, 1994
Creator: Tomy, C. V.; Chang, L. J.; Paul, D. M.; Andersen, N. H. & Yethiraj, M.
System: The UNT Digital Library
Absorption of intense microwaves and ion acoustic turbulence due to heat transport (open access)

Absorption of intense microwaves and ion acoustic turbulence due to heat transport

Measurements and calculations of the inverse bremsstrahlung absorption of intense microwaves are presented. The isotropic component of the electron distribution becomes flat-topped in agreement with detailed Fokker-Planck calculations. The plasma heating is reduced due to the flat-topped distributions in agreement with calculations. The calculations show that the heat flux at high microwave powers is very large, q{sub max} {approx} 0.3 n{sub e}v{sub e}T{sub e}. A new particle model to, calculate the heat transport inhibition due to ion acoustic turbulence in ICF plasmas is also presented. One-dimensional PIC calculations of ion acoustic turbulence excited due to heat transport are presented. The 2-D PIC code is presently being used to perform calculations of heat flux inhibition due to ion acoustic turbulence.
Date: February 4, 1994
Creator: De Groot, J. S.; Liu, J. M. & Matte, J. P.
System: The UNT Digital Library
Fast electrons, filamented laser light, and the fast ignitor (open access)

Fast electrons, filamented laser light, and the fast ignitor

We report on the absorption of laser energy that results when an ultra-intense laser pulse is incident onto a sharp vacuum-plasma boundary, where the initial shelf density of the plasma is much greater than the critical density, n{sub cr}. It is found that 2-D effects greatly increase the amount of absorption into hot electrons, over the amount predicted using 1-D theory. In particular, a scaling for the absorption as a function of density, for a fixed laser intensity, implies that the absorption will be of order 30% for densities well in excess of The interaction is studied using both 1- and 2- dimensional particle-in-cell (PIC) 100 n{sub cr} simulations. The 1-D results agree quite well with a simple scaling of JxB heating, where the laser electric field penetrates a skin depth into the overdense plasma and subsequently heats electrons. In 2-D, when the laser is incident at an angle, the absorption is seen to increase substantially due to a form of resonant absorption that occurs in steep density profiles. We find that the inclusion of kinetic and multi-dimensional effects are crucial to obtaining a complete picture of the interaction. The ability of ultra-intense lasers to produce acceptable amounts o f …
Date: February 4, 1994
Creator: Kruer, W. L. & Wilks, S. C.
System: The UNT Digital Library