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Bicriteria network design problems (open access)

Bicriteria network design problems

We study several bicriteria network design problems phrased as follows: given an undirected graph and two minimization objectives with a budget specified on one objective, find a subgraph satisfying certain connectivity requirements that minimizes the second objective subject to the budget on the first. Define an ({alpha}, {beta})-approximation algorithm as a polynomial-time algorithm that produces a solution in which the first objective value is at most {alpha} times the budget, and the second objective value is at most {alpha} times the minimum cost of a network obeying the budget oil the first objective. We, present the first approximation algorithms for bicriteria problems obtained by combining classical minimization objectives such as the total edge cost of the network, the diameter of the network and a weighted generalization of the maximum degree of any node in the network. We first develop some formalism related to bicriteria problems that leads to a clean way to state bicriteria approximation results. Secondly, when the two objectives are similar but only differ based on the cost function under which they are computed we present a general parametric search technique that yields approximation algorithms by reducing the problem to one of minimizing a single objective of the …
Date: December 31, 1994
Creator: Marathe, M. V.; Ravi, R.; Sundaram, R.; Ravi, S. S.; Rosenkrantz, D. J. & Hunt, H. B., III
Object Type: Article
System: The UNT Digital Library
Bioenergy: What`s in it for the grower? The cost of producing dedicated energy crops. Comparisons with conventional crops (open access)

Bioenergy: What`s in it for the grower? The cost of producing dedicated energy crops. Comparisons with conventional crops

Dedicated energy crops must be at least as profitable as conventional crops that could be grown on a given site before farmers will produce energy crops on that site. This report concentrates on the cost of producing dedicated energy crops and compare those costs to the profitability of conventional crops. This comparison allows one to estimate a breakeven price, that is, a price for which the profitability of dedicated energy crops is equivalent to the profitability of conventional crops. Switchgrass and hybrid poplar have been chosen as representative herbaceous and woody crop species for the estimation.
Date: December 31, 1994
Creator: Walsh, M.
Object Type: Article
System: The UNT Digital Library
Boiling heat transfer in compact heat exchangers (open access)

Boiling heat transfer in compact heat exchangers

Small circular and noncircular channels are representative of flow passages in compact evaporators and condensers. This paper describes results of an experimental study on heat transfer to the flow boiling of refrigerant- 12 in a small circular tube of diameter = 2.46 mm. The objective of the study was to assess the effect of channel size on the heat transfer coefficient and to obtain additional insights relative to the heat transfer mechanisms. The flow channel was made of brass and had an overall length of 0.9 m. The channel wall was electrically heated, and temperatures were measured on the channel wall and in the bulk fluid stream. Voltage taps were located at the same axial locations as the stream thermocouples to allow testing over an exit quality range of 0.21 to 0.94 and a large range of mass flux (63 to 832 kg/m{sup 2}s) and heat flux (2.5 to 59 kW/m{sup 2}). Saturation pressure was nearly constant, averaging 0.82 MPa for most of the testing; a few test data were also taken at a constant lower pressure of 0.52 MPa. Local heat transfer coefficients were determined experimentally. Analysis provided additional support for the conclusion, arrived at from previous studies, that …
Date: December 31, 1994
Creator: Tran, T. N.; Wambsganss, M. W. & France, D. M.
Object Type: Article
System: The UNT Digital Library
A borehole instrumentation program for characterization of unsaturated-zone percolation (open access)

A borehole instrumentation program for characterization of unsaturated-zone percolation

A borehole instrumentation and monitoring program has been designed by the US Geological Survey to support site characterization of unsaturated-zone percolation at Yucca Mountain, Nye County, Nevada. This program provides a means of defining the unsaturated-zone fluid flow (liquid and gas) potential field in a setting that incorporates large-scale stratigraphic and structural features, and the influences of geothermal heat flow and atmospheric pressure changes. Data derived from this program will be used to evaluate the suitability of Yucca Mountain as a mined geologic-repository for the storage of high-level, radioactive waste. These data include in-situ temperature, pneumatic pressure, and water potential. In addition, the instrumentation program provides facilities for gas-sampling, gas-tracer diffusion testing, water-injection testing, water-level monitoring, neutron moisture-meter monitoring, temperature profiling, and in-situ recalibration of the downhole sensors. The program included testing and development of: (1) precision sensors for measurement; (2) a downhole instrumentation-station-apparatus to house the sensors, recalibrate sensors in-situ, and allow access to instrument stations for other testing purposes; and (3) surface-based support and instrumentation facilities.
Date: December 31, 1994
Creator: Kume, J. & Rousseau, J.P.
Object Type: Article
System: The UNT Digital Library
Boron neutron capture therapy of glioblastoma multiforme using the p- boronophenylalanine-fructose complex and epithermal neutrons (open access)

Boron neutron capture therapy of glioblastoma multiforme using the p- boronophenylalanine-fructose complex and epithermal neutrons

The amino acid analogue p-boronophenylalanine (BPA) is under investigation as a neutron capture agent for BNCT of glioblastoma multiforme. A series of patients undergoing surgical removal of tumor received BPA orally as the free amino acid. Favorable tumor/blood boron concentration ratios were obtained but the absolute amount of boron in the tumor would have been insufficient for BNCT. BPA can be solubilized at neutral pH by complexation with fructose (BPA-F). Studies with rats suggest that intraperitoneal injection of BPA-F complex produces a much higher tumor boron concentration to rat intracerebral 9L gliosarcoma that were possible with oral BPA. Higher boron concentrations have allowed higher tumor radiation doses to be delivered while maintaining the dose to the normal brain vascular endothelium below the threshold of tolerance. The experience to date of the administration of BPA-F to one patient is provided in this report.
Date: December 31, 1994
Creator: Coderre, J. A.; Chanana, A. D.; Joel, D. D.; Liu, H. B.; Slatkin, D. N.; Wielopolski, L. et al.
Object Type: Article
System: The UNT Digital Library
Brookhaven highlights 1994 (open access)

Brookhaven highlights 1994

Established in 1947 on Long Island, New York, on the site of the former army Camp Upton, BNL is a multidisciplinary laboratory that carries out basic and applied research in the physical, biomedical and environmental sciences and in selected energy technologies. The Laboratory is managed by Associated Universities, Inc., under contract to the US Department of Energy. BNL`s annual budget is about $400 million, and the Laboratory`s facilities are valued at replacements cost in excess of over $2.8 billion. Employees number around 3,300,and over 4,000 guests, collaborators and students come each year to use the Laboratory`s facilities and work with the staff. Scientific and technical achievements at BNL have made their way into daily life in areas as varied as health care, construction materials and video games. The backbone of these developments is fundamental research, which is and always will be an investment in the future.
Date: December 31, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Building an electronic book on the Internet: ``CSEP -- an interdisciplinary syllabus for teaching computational science at the graduate level`` (open access)

Building an electronic book on the Internet: ``CSEP -- an interdisciplinary syllabus for teaching computational science at the graduate level``

The Computational Science Education Project was initiated in September 1991, by the Department of Energy to develop a syllabus for teaching interdisciplinary computational science. CSEP has two major activities. The writing and maintenance of an electronic book (e-book) and educational outreach to the computational science communities through presentations at professional society meetings, journal articles, and by training educators. The interdisciplinary nature of the project is intended to contribute to national technological competitiveness by producing a body of graduates with the necessary skills to operate effectively in high performance computing environments. The educational outreach guides and supports instructors in developing computational science courses and curricula at their institutions. The CSEP e-book provides valuable teaching material around which educators have built. The outreach not only introduces new educators to CSEP, but also establishes a synergistic relationship between CSEP authors, reviewers and users.
Date: December 31, 1994
Creator: Oliver, C. E.; Strayer, M. R. & Umar, V. M.
Object Type: Article
System: The UNT Digital Library
Buried Waste Integrated Demonstration lessons learned: 1993 technology demonstrations (open access)

Buried Waste Integrated Demonstration lessons learned: 1993 technology demonstrations

An integrated technology demonstration was conducted by the Buried Waste Integrated Demonstration (BWID) at the Idaho National Engineering Laboratory Cold Test Pit in the summer of 1993. This program and demonstration was sponsored by the US Department of Energy Office of Technology Development. The demonstration included six technologies representing a synergistic system for the characterization and retrieval of a buried hazardous waste site. The integrated technology demonstration proved very successful and a summary of the technical accomplishments is presented. Upon completion of the integrated technology demonstration, cognizant program personnel participated in a lessons learned exercise. This exercise was conducted at the Simplot Decision Support Center at Idaho State University and lessons learned activity captured additional information relative to the integration of technologies for demonstration purposes. This information will be used by BWID to enhance program planning and strengthen future technology demonstrations.
Date: December 31, 1994
Creator: Kostelnik, K. M. & Owens, K. J.
Object Type: Article
System: The UNT Digital Library
C15 intermetallic compounds HfV{sub 2}+Nb (open access)

C15 intermetallic compounds HfV{sub 2}+Nb

Phase fields and equilibria in the Hf-V-Nb system were determined using a combination-of SEM, EDS and x-ray diffraction. The structural stability of the C15 HfV{sub 2+}Nb was studied by x-ray diffraction and specific heat measurements. The elastic constants of C15 HfV{sub 2+}Nb were measured by the resonant ultrasound spectroscopy technique. First-principle quantum mechanical calculations based on the local-density-functional theory have been employed to study the total energy and electronic structure of C15 HfV{sub 2}, which can be used to understand the physical and metallurgical properties of the C15 intermetallics HfV{sub 2+}Nb.
Date: December 31, 1994
Creator: Chu, F.; Chen, S. P.; Mitchell, T. E.; Pope, D. P. & Liu, C. T.
Object Type: Article
System: The UNT Digital Library
California low-temperature geothermal resources update: 1993 (open access)

California low-temperature geothermal resources update: 1993

The US Department of Energy -- Geothermal Division (DOE/GD) recently sponsored the Low-Temperature Geothermal Resources and Technology Transfer Program to bring the inventory of the nation`s low- and moderate-temperature geothermal resources up to date and to encourage development of the resources. The Oregon Institute of Technology, Geo-Heat Center (OIT/GHC) and the University of Utah Research Institute (UURI) established subcontracts and coordinated the project with the state resource teams from the western states that participated in the program. The California Department of Conservation, Division of Mines and Geology (DMG) entered into contract numbered 1092--023(R) with the OIT/GHC to provide the California data for the program. This report is submitted in fulfillment of that contract.
Date: December 31, 1994
Creator: Youngs, L. G.
Object Type: Report
System: The UNT Digital Library
Cancer of the melanocytic system (open access)

Cancer of the melanocytic system

Within reasonably homogenous populations, skin cancer increases toward low latitudes, but this association does not indicate the wavelength regions involved in cancer induction. At present, the only animal model suitable for determining the wavelengths effective in melanoma induction are certain inter- and intraspecies hybrids of the small fish, Xiphophorus. Genetic evidence indicates that the hybrids contain only one tumor suppressor gene and, therefore, are very sensitive to cancer induction by single exposures to light. 5-Day old fish were exposed in spectrophotometer cuvettes, to different monochromatic wavelengths and fluences. The fish were kept for two months in tanks shielded with yellow plastic, so as to minimize the possibility of photoreactivation, and were scored at four months. The melanoma prevalence increased with exposure to a maximum of {approximately} 0.5. The fluence-response curves were fitted to surviving fraction = a+b(l-e{sup {minus}kE}), where a is the background prevalence with no exposure, b is the maximum induced prevalence, k is the sensitivity parameter (the cross section for melanoma induction), and E is the incident fluence. The value of k at 302 nm was 0.05 m{sup 2}/J giving a mean melanoma inducing exposure, for swimming fish, of 200 J/m{sup 2}, corresponding to 3.5 cyclobutane pyrimidine dimers …
Date: December 31, 1994
Creator: Setlow, R.B.
Object Type: Article
System: The UNT Digital Library
Case Study and Presentation of the DOE Treatability Group Concept for Low-Level and Mixed Waste Streams (open access)

Case Study and Presentation of the DOE Treatability Group Concept for Low-Level and Mixed Waste Streams

The Federal Facility Compliance Act of 1992 requires the US Department of Energy (DOE) to prepare an inventory report of its mixed waste and treatment capacities and technologies. Grouping waste streams according to technological requirements is the logical means of matching waste streams to treatment technologies, and streamlines the effort of identifying technology development needs. To provide consistency, DOE has developed a standard methodology for categorizing waste into treatability groups based on three characteristic parameters: radiological, bulk physical/chemical form, and regulated contaminant. Based on category and component definitions in the methodology, descriptive codes or strings of codes are assigned under each parameter, resulting in a waste characterization amenable to a computerized format for query and sort functions. By using only the applicable parameters, this methodology can be applied to all waste types generated within the DOE complex: radioactive, hazardous, mixed, and sanitary/municipal. Implementation of this methodology will assist the individual sites and DOE Headquarters in analyzing waste management technology and facility needs.
Date: December 31, 1994
Creator: Kirkpatrick, T. D.; Heath, B. A. & Davis, K. D.
Object Type: Article
System: The UNT Digital Library
Catalytic conversion of light alkanes-proof-of-concept stage -- Phase 6. Final report, February 1--October 31, 1994 (open access)

Catalytic conversion of light alkanes-proof-of-concept stage -- Phase 6. Final report, February 1--October 31, 1994

During the course of the first three years of the Cooperative Agreement, the authors uncovered a family of metal perhaloporphyrin complexes which had unprecedented activity for the selective air-oxidation of light alkanes to alcohols. The reactivity of light hydrocarbon substrates with air or oxygen was in the order: isobutane > propane > ethane > methane, in accord with their homolytic bond dissociation energies. Isobutane was so reactive that the proof-of-concept stage of a process for producing tert-butyl alcohol from isobutane was begun (Phase 5). It was proposed that as more active catalytic systems were developed (Phases 4, 6), propane, then ethane and finally methane oxidations will move into this stage (Phases 7 through 9). As of this writing, however, the program has been terminated during the later stages of Phase 5 and 6 so that further work is not anticipated. 72 refs.
Date: December 31, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Catalytic extraction processing of contaminated scrap metal (open access)

Catalytic extraction processing of contaminated scrap metal

The contract was conceived to establish the commercial capability of Catalytic Extraction Processing (CEP) to treat contaminated scrap metal in the DOE inventory. In so doing, Molten Metal Technology, Inc. (MMT), pursued the following objectives: demonstration of the recycling of ferrous and non-ferrous metals--to establish that radioactively contaminated scrap metal can be converted to high-grade, ferrous and non-ferrous alloys which can be reused by DOE or reintroduced into commerce; immobilize radionuclides--that CEP will concentrate the radionuclides in a dense vitreous phase, minimize secondary waste generation and stabilize and reduce waste volume; destroy hazardous organics--that CEP will convert hazardous organics to valuable industrial gases, which can be used as feed gases for chemical synthesis or as an energy source; recovery volatile heavy metals--that CEP`s off-gas treatment system will capture volatile heavy metals, such as mercury and lead; and establish that CEP is economical for processing contaminated scrap metal in the DOE inventory--that CEP is a more cost-effective and, complete treatment and recycling technology than competing technologies for processing contaminated scrap. The process and its performance are described.
Date: December 31, 1994
Creator: Griffin, T.P. & Johnston, J.E.
Object Type: Report
System: The UNT Digital Library
Cavity formation and impurity gettering in He-implanted Si (open access)

Cavity formation and impurity gettering in He-implanted Si

Cavity microstructures formed in Si after ion implantation of He and annealing at 700 C or above are examined with cross-section transmission electron microscopy. A threshold concentration of 1.6 at.% He is identified to form cavities that survive such anneals. The cavities coarsen with a constant volume of 15 nm{sup 3}/nm{sup 2} (per wafer surface area), corresponding to {approximately}0.75 lattice sites per implanted He atom. The internal area of the cavities is 3--7 times that of the wafer surface area for fluences of 1 {times} 10{sup 17} He/cm{sup 2}. Transition metal atoms (Cu, Ni, Co, Fe, Au) are shown to be strongly trapped (1.5--2.2 eV) on the cavity walls by chemisorption. Whereas Cu, Au and Ni are bound more strongly to the cavity sites than to their respective precipitated phases, Co and Fe are more strongly bound to their silicides; nonetheless, appreciable trapping of Co and Fe does occur in equilibrium with the silicides. Cavity trapping appears to be an effective gettering mechanism at low impurity levels, as needed to meet future microelectronics device requirements.
Date: December 31, 1994
Creator: Follstaedt, D. M.; Myers, S. M.; Petersen, G. A. & Medernach, J. W.
Object Type: Report
System: The UNT Digital Library
CD-ROM in the age of internet (open access)

CD-ROM in the age of internet

Networks are hot and CD-ROM is also hot, but how do they mix? CD-ROM is a relatively inexpensive medium for storing and delivering information, and increasingly, users are connected to networks. But the technologies have developed separately, and there are obstacles to their integration. Drawing on their experience networking CD-ROMs at Oak Ridge National Laboratory, the authors discuss CD-ROM`s strengths and weaknesses as a technology for delivering information to the desktop. CD-ROM networking solutions are LAN-based, not ``open systems.`` Despite this limitation, due to the large number of information resources available on CD-ROM and the relative ease of installing and maintaining databases on CD-ROM, CD-ROMs remain an essential piece of the electronic information puzzle.
Date: December 31, 1994
Creator: Conrad, B. & Depp, D.
Object Type: Article
System: The UNT Digital Library
CdTe/CdZnTe Characterization and Detector Development. Final report (open access)

CdTe/CdZnTe Characterization and Detector Development. Final report

None
Date: December 31, 1994
Creator: Lynn, K G
Object Type: Report
System: The UNT Digital Library
CEBAF at higher energies (open access)

CEBAF at higher energies

This report summarizes topics in hadron spectroscopy and production which could be addressed at CEBAF with an energy upgrade to E{sub gamma} = 8 GeV and beyond. The topics discussed include conventional meson and baryon spectroscopy, spectroscopy of exotica (especially molecules and hybrids), CP and CPT tests using {phi} mesons, and new detector and accelerator options.
Date: December 31, 1994
Creator: Barnes, T. & Napolitano, J.
Object Type: Article
System: The UNT Digital Library
Center for Volcanic and Tectonic Studies: 1992--1993 annual report (open access)

Center for Volcanic and Tectonic Studies: 1992--1993 annual report

The annual report of the Center for Volcanic Studies (CVTS) contains a series of papers, reprints and a Master of Science thesis that review the progress made by the CVTS between October 1, 1992 and February 1, 1994. During this period CVTS staff focused on several topics that have direct relevance to volcanic hazards related to the proposed high-level nuclear waste repository at Yucca Mountain, Nevada. These topics include: (1) polygenetic/polycyclic volcanism in Crater Flat, Nevada; (2) the role of the mantle during crustal extension; (3) the detailed geology of Crater Flat, Nevada; (4) Pliocene volcanoes in the Reveille Range, south-central Nevada; (5) estimating the probability of disruption of the proposed repository by volcanic eruptions. This topic is being studied by Dr. C.H. Ho at UNLV. The report contains copies of these individual papers as they were presented in various conference proceedings.
Date: December 31, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Ceramic membranes for partial oxygenation of hydrocarbon fuels to high-value-added products (open access)

Ceramic membranes for partial oxygenation of hydrocarbon fuels to high-value-added products

This report describes the design of a membrane reactor for converting methane into value added products. The design includes an outer tube of perovskite which contacts air, an inner tube of zirconium oxide which contacts methane, and a bonding layer of a mixture of zirconium oxide and perovskite.
Date: December 31, 1994
Creator: Balachandran, U.; Dusek, J.T.; Kleefisch, M.S. & Kobylinski, T.P.
Object Type: Patent
System: The UNT Digital Library
Cermet crucible for metallurgical processing (open access)

Cermet crucible for metallurgical processing

A cermet crucible for metallurgically processing metals having high melting points comprising a body consisting essentially of a mixture of calcium oxide and erbium metal, the mixture comprising calcium oxide in a range between about 50 and 90% by weight and erbium metal in a range between about 10 and 50% by weight.
Date: December 31, 1994
Creator: Boring, C.P.
Object Type: Patent
System: The UNT Digital Library
Cesium cobaltdicarbollide-solubility, precipitation, and reactivity in basic aqueous solution (open access)

Cesium cobaltdicarbollide-solubility, precipitation, and reactivity in basic aqueous solution

The title compound, Cs{sup +}[Co((3)-1,2-C{sub 2}B{sub 9}H{sub 11}){sub 2}]{sup {minus}}(CsCDC), was precipitated with a NaCDC solution from solutions containing CsCl. The reaction was followed by measuring loss of light intensity as the precipitate formed. The [Cs{sup +}] and [CDC{sup {minus}}] at the point of precipitation were estimated and approximate values of the K{sub sp} for CsCDC determined at room temperature: 8 {times} 10{sup {minus}6} (water), 7 {times} 10{sup {minus}6} (1 M NaOH), and 2 {times} 10{sup {minus}6} (5M NaCl/0.1 M KOH/1.0 M NaOH). In some cases, NaCDC precipitated from solution when added to the latter salt solution. For the medium, 5 M NaNO{sub 3}/0.1 M KOH/1.0 M NaOH a four-fold excess of NaCDC was added to a 10mM Cs{sup +} solution at 40{degrees}C and the [CDC{sup {minus}}] measured spectrophotometrically. Only CsCDC precipitated, and a K{sub sp} of 3.9 {times} 10{sup {minus}6} was determined. The solubilities of CsCDC were measured in NaNO{sub 3} and NaCl solutions at 30{sub C} as a function of the Na salt concentration. Reaction of the CDC{sup {minus}} with OH{sup {minus}} slowly produces B(OH{sub 4}{sup {minus}}, H{sub 2}, and CoO(OH). Reaction of 22 {mu}M CsCDC with 1M NaOH has a first order rate constant at 56{degrees}C of …
Date: December 31, 1994
Creator: McCabe, D. J.; Fanning, J. C.; Hugg, L. A.; Smith, W. A.; Terrell, A. S.; Yasinsac, L. et al.
Object Type: Report
System: The UNT Digital Library
The challenge of implementing an IRP process in Asia: The case of Hainan Province, China (open access)

The challenge of implementing an IRP process in Asia: The case of Hainan Province, China

Developing a modern electric power sector is necessary for economic growth and development to proceed. Institutions to implement an IRP (integrated resource planning) process do not exist in many countries. Hainan`s economy is growing rapidly with a concomitant increase in electricity demand. This is an ideal time in Hainan`s development to implement an IRP process. The challenge is for Hainan to develop institutions and incentive mechanisms for HEPCO (Hainan Electric Power Co.) to adopt cost-based pricing, run DSM programs, construct renewable generating plants, etc. One proposal is to great a Hainan government-wide IRP committee.
Date: December 31, 1994
Creator: Hill, L.J.
Object Type: Article
System: The UNT Digital Library
Changing mass liner system for generation of soft X-radiation (open access)

Changing mass liner system for generation of soft X-radiation

This report is issued in compliance with Clause F.4.2 of Contract 4769M0014-9Y ``Design study for X-ray generation``. In the first report (Clause F.4.1 of Contract) three systems were considered to solve the formulated problem. All of them were designed on the basis of employment of {O}400 mm disk explosive-magnetic generators (DEMG) as an energy source using a high-speed (25--30 cm/{micro}s) liner converging to the axis. The considered systems differs in modes of current pulse formation. For further effort the customer has chosen System 3 with the changing mass liner. In accordance with this fact this report discusses basic theoretical and computational results obtained to date for System 3. Further development of the theory of the considered system is suggested in the context of the series of experiments the ultimate goal of which is to generate soft X-radiation. Basic stages of the effort to generate soft X-radiation are discussed on the basis of the schedule given with consideration of some corrections which occurred when the system type had been selected.
Date: December 31, 1994
Creator: Mokhov, V. N.; Buyko, A. M.; Burenkov, O. M.; Garanin, S. F.; Startsev, A. I. & Yakubov, V. B.
Object Type: Report
System: The UNT Digital Library