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Distributed discrete event simulation. Final report

Description: The presentation given here is restricted to discrete event simulation. The complexity of and time required for many present and potential discrete simulations exceeds the reasonable capacity of most present serial computers. The desire, then, is to implement the simulations on a parallel machine. However, certain problems arise in an effort to program the simulation on a parallel machine. In one category of methods deadlock care arise and some method is required to either detect deadlock and recover from it or to avoid deadlock through information passing. In the second category of methods, potentially incorrect simulations are allowed to proceed. If the situation is later determined to be incorrect, recovery from the error must be initiated. In either case, computation and information passing are required which would not be required in a serial implementation. The net effect is that the parallel simulation may not be much better than a serial simulation. In an effort to determine alternate approaches, important papers in the area were reviewed. As a part of that review process, each of the papers was summarized. The summary of each paper is presented in this report in the hopes that those doing future work in the area will be able to gain insight that might not otherwise be available, and to aid in deciding which papers would be most beneficial to pursue in more detail. The papers are broken down into categories and then by author. Conclusions reached after examining the papers and other material, such as direct talks with an author, are presented in the last section. Also presented there are some ideas that surfaced late in the research effort. These promise to be of some benefit in limiting information which must be passed between processes and in better understanding the structure of a distributed simulation. Pursuit ...
Date: February 1, 1988
Creator: De Vries, R.C.
Partner: UNT Libraries Government Documents Department

Comments on the linear transverse coupling

Description: One of the most troublesome phenomena during the commissioning of synchrotrons is the linear horizontal-vertical coupling. Because of its linear nature, on can in principle obtain the analytical solution provided that all sources of skew quadrupole field are known completely in the entire ring. In spite of all this, many standard diagnostic procedures and measurements become rather confusing and often lead to wrong conclusions. The purpose of this note is to explain some of the simpler relation which are useful in understanding measurement of tunes and the amount of coupling.
Date: February 1, 1988
Creator: Ohnuma, S.
Partner: UNT Libraries Government Documents Department

Tune shifts caused by horizontal closed orbit deviations in sextupoles

Description: One of the uncomfortable features of the Chasman-Green lattice is that the chromaticity-correcting sextupoles are all very strong compared with those in the FODO-type lattice. Because of their strengths, when their arrangement creates certain harmonic components, the dynamic aperture is severely reduced and on is forced to add more sextupoles to eliminate harmful harmonic components.During the course of design studies, S. Kramer has made many computer runs to investigate tune shifts resulting from horizontal orbit deviations in sextupoles. An interesting observation is that the average tune shift is definitely related to the dependence of tunes on the betatron oscillation amplitudes (or, equivalently, the transverse emittances). This note is an ``attempt`` to explain the connection at least qualitatively. It is no more than an attempt since the explanation is not yet quantitative and it may even be somewhat inconsistent.
Date: February 1, 1988
Creator: Ohnuma, S.
Partner: UNT Libraries Government Documents Department

Comparison of air and water quenching of HDS slugs

Description: This memorandum recommends the use of water quenching, rather than air quenching, for pressed slugs in any future project to substantially update the Building 313-M slug manufacturing facility. At the outset of the recently canceled Project S-4092, Improved Slug Processing Facility (ISPF), 313-M, consensus of the SRP liaison team was to replace the existing water quench facility with air quenching. Principal motivations were to eliminate a liquid waste stream, reduce the quantity of process water used, and attain a more reliable mechanical system. During the ensuing years, unforeseen difficulties with air quenching have been realized. Also, effective methods of reducing and treating the waste streams generated by water quenching have been developed. Both methods the author believes will work. However, the propriety of either method of quenching is a function of the system into which it is being incorporated. Each method carried with it a lot of concealed constraint s and carefully designed additional equipment. There is today a consensus that water quenching is preferable. For future reference, some advantages and disadvantages of the two quenching methods are discussed.
Date: February 3, 1988
Creator: Burk, J. A.
Partner: UNT Libraries Government Documents Department

Porosity in as-cast U-Al alloy

Description: This memorandum documents a study that showed a cyclic occurrence of porosity in U-Al alloys produced in Building 321-M. Review of process data shows that the extent of porosity is more pronounced in months of warm, humid weather and less pronounced in cooler, drier months. This porosity is most likely caused by hydrogen, which becomes dissolved in the molten U-Al alloy during casting. Although excessive porosity was the cause of some observed process anomalies, this type of porosity has no significant effect on yield or fuel tube quality.
Date: February 25, 1988
Creator: Rhode, F. C.
Partner: UNT Libraries Government Documents Department

ZPPR progress report: November 1987-January 1988

Description: This report details activities for the time period of November, 1987 through January, 1988. Further results are presented from the axially heterogeneous assembly ZPPR-17, a part of the JUPITER-III program. The loading of the ZPPR-17C assembly, with 13 half-inserted control rods, is described along with operational measurements, calculation models, and measurements and prediction of criticality. From ZPPR-17A, calculated and measured results are given for reaction rates and measured results for bowing, expansion and small sample worth experiments. From the earlier metal-fuel ZPPR-15 program results are given for measurements and calculations of Doppler reactivity coefficients.
Date: February 15, 1988
Creator: Collins, P.J. & Brumbach, S.B.
Partner: UNT Libraries Government Documents Department

Correction of closed orbit distortions in the horizontal direction

Description: Many computer programs with a variety of algorithms exist for controlling the closed orbit in synchrotrons. The scope of this note is rather modest in comparison. Based on a simple model, a study has been made to find out statistically how much kick angle is needed by each steering element and how much residual closed orbit deviation should be expected when the closed orbit is steered to go through the center of seven position monitors (M{sub 2} through M{sub 8}) in each cell. Seven independent kicks are supplied by two trim dipoles B{sub U} and B{sub D}, and six steering elements (H{sub 1} through H{sub 6}) with H{sub 3} and H{sub 4} assumed to have the same kick angle. If it is necessary to remove H{sub 3} to make a space there for a correction skew quadrupole (in every other cell), the kick angle of H{sub 4} would have to be doubled.
Date: February 1, 1988
Creator: Ohnuma, S.
Partner: UNT Libraries Government Documents Department

Description of ground motion data processing codes: Volume 3

Description: Data processing codes developed to process ground motion at the Nevada Test Site for the Weapons Test Seismic Investigations Project are used today as part of the program to process ground motion records for the Nevada Nuclear Waste Storage Investigations Project. The work contained in this report documents and lists codes and verifies the ``PSRV`` code. 39 figs.
Date: February 1, 1988
Creator: Sanders, M.L.
Partner: UNT Libraries Government Documents Department

Plan for waste package environment for NNWSI [Nevada Nuclear Waste Storage Investigations]

Description: The purpose and objective of the Waste Package Environment task is to establish and characterize the environmental processes affecting the near-field repository host rock after waste package emplacement. These processes, which reflect the perturbation induces in the environment by engineering effects and by the waste package decay heat and radiation, will influence chemical, mineralogical and hydrological features of the environment. The thermal and radiation output of the waste packages will change with time, resulting in an environment in which the chemical, mineralogical and physical attributes may also change through time. To assure that waste package design considerations reflect the characteristics of this evolving environment, it is necessary to determine the range of conditions that may develop in the pre- and post-emplacement waste package environment. To assure that the emplacement configurations do not compromise the lifetime of the repository or the waste packages, the design of the emplacement configuration must also consider the environmental features. Recognition of these requirements resulted in the development of the issue an information needs. 20 refs.
Date: February 1, 1988
Creator: Glassley, W.E.
Partner: UNT Libraries Government Documents Department

Dried plutonium nitrate decontamination using HNO{sub 3} or Freon 113

Description: A request was made of the Separations Technology Laboratory to perform tests to determine the relative effectiveness of Freon 113 and 18% (3.15M) nitric acid on removing dried plutonium nitrate from Hypalon{reg_sign} gloves destined for use in F B-Line. Freon 113 was very inefficient for removing dried plutonium nitrate under conditions of moderate agitation of the liquid in contact with the dried compound. Nitric acid proved to be an excellent agent for decontaminating purposes for both the gloves and for the Pyrex glass. In tests conducted on the glass or on the gloves on which dried plutonium nitrate had not been removed by Freon 113, followup with nitric acid efficiently removed the residual plutonium nitrate. Tests were also conducted to give some measure of the resistance of the Hypalon glove to continuous contact with 18% HNO{sub 3} or with Freon 113. Following two weeks` immersion, there was little physical difference noted from the starting material, except the glove piece immersed in the Freon underwent an 8% weight gain.
Date: February 4, 1988
Creator: Holcomb, H. P.
Partner: UNT Libraries Government Documents Department

Test dissolution of Hanford scrap oxide, HRA-40

Description: Two portions from a single sample of Hanford scrap plutonium oxide (12% Pu{sup 240}), account HRA-40, were dissolved in the Separations Technology Laboratory as requested. Test conditions, including oxide-to-solvent ratio were very similar to those used in the process. Both test portions dissolved quite readily in 14M HNO{sub 3}-0.2 M HF in a boiling water bath. Efficient agitation of the oxide in the solvent was instrumental in ensuring quick, thorough dissolution.
Date: February 16, 1988
Creator: Holcomb, H.P.
Partner: UNT Libraries Government Documents Department

Progress in evaluation of radionuclide geochemical information developed by DOE high-level nuclear waste repository site projects: Report for April 1986-September 1987

Description: Experiments were conducted with tuff from the proposed high-level nuclear waste site at Yucca Mountain, Nevada. Batch sorption ratio determinations were conducted for strontium, cesium, uranium, and technetium onto samples of tuff using real and synthetic groundwater J-13. There were no significant differences in sorption ratios in experiments with real and synthetic groundwater. Columns 1 cm in diameter and about 5 cm long were constructed, and experiments were conducted with the objective of correlating the results of batch and the column experiments. The characteristics of the columns were tested by determination of elution curves in J-13 containing tritium and technetium as the TcO{sub 4}{sup -} ion. For strontium and cesium, fairly good correlation between values of the sorption ratio obtained by the two methods was observed. Little or no technetium sorption was observed with either method. The elution peaks obtained with neptunium and uranium were asymmetrical and the shapes were often complex, observations which suggest irreversibilities in the sorption reaction. An experiment was performed to provide information on the compositions of the first groundwaters that will contact waste canisters in a tuff-hosted repository after very near field temperatures have cooled to below 100{degree}C. Synthetic groundwater J-13 was slowly dripped onto a slab of tuff maintained at 95-100{degree}C, and the result was a thin encrustation of solids on the slab as the water evaporated. Fresh J-13 groundwater was then allowed to contact the encrustation in a vessel maintained at 90{degree}C. The principal result of the experiment was a significant loss of calcium and magnesium from the fresh J-13 groundwater.
Date: February 1, 1988
Creator: Meyer, R.E.; Arnold, W.D.; Blencoe, J.G.; O`Kelley, G.D. & Land, J.F.
Partner: UNT Libraries Government Documents Department

Laboratory and field studies related to the Radionuclide Migration project: Progress report, October 1, 1986-September 30, 1987

Description: In this report we describe the research done by personnel of the Los Alamos National Laboratory in support of the Radionuclide Migration project during FY 1987. We are engaged in collecting data concerning the movement of radionuclides at three locations on the Nevada Test Site. We continue to monitor the elution of tritium and krypton from the RNM-2S well at the Cambric site and have described in detail the elution of {sup 36}Cl from the same well. The data from this field study provide us with the opportunity to test the validity of several models of solute transport through geologic media. We have detected tritium and fission products in a water sample from the hole UE20n #1, which was drilled this year at the Cheshire site on Pahute Mesa. We are also continuing our efforts to learn how radionuclides have moved in test areas 3 and 4 near the Aleman site. Our laboratory work this year includes (1) a characterization of the size and density of two stable plutonium(IV) colloid suspensions prepared by different techniques and (2) a study of the transmission of colloidal-size polystyrene beads through crushed-rock columns. 18 refs., 7 figs., 9 tabs.
Date: February 1, 1988
Creator: Thompson, J.L. (comp.)
Partner: UNT Libraries Government Documents Department

The reaction of glass during gamma irradiation in a saturated tuff environment: Part 3, long-term experiments at 1 x 10{sup 4}rad/hour

Description: Savannah River Laboratory 165 type glass was leached with equilibrated J-13 groundwater at 90{degree}C for times up to 182 days. These experiments were performed as part of an effort by the Nevada Nuclear Waste Storage Investigations Project to assess the importance of radiation effects on repository performance and waste glass corrosion. The gamma radiation field used in this work was 1. 0 +- 0.2 x 10{sup 4} rad/h. Glass dissolution is notably incongruent throughout the entire experimental periods and normalized releases follow the sequence Li {ge} Na {ge} B {approx_equal} U {ge} Si. The normalized leach rates of these elements, as well as the measured growth rates of the reaction layers, decreased with time. The only significant variation observed in the abundance of anions is the systematic decrease in NO{sub 3}/sup {minus}//NO{sub 2}/sup {minus}/ ratio from the starting EJ-13 groundwater to the EJ-13 blank experiments to the tuff- and glass-containing experiments. A leaching model that is consistent with the observed solution data and depth profiles is presented. The applicability and limitation of the present results in predicting the actual interactions that may occur in the NNWSI repository are discussed. 35 refs., 30 figs., 12 tabs.
Date: February 1, 1988
Creator: Abrajano, T.A. Jr.; Bates, J.K.; Gerding, T.J. & Ebert, W.L.
Partner: UNT Libraries Government Documents Department

Rail abandonments in the South and their effect on NWPA rail shipments

Description: The railroad industry will have a very critical role in the eventual shipping of commercial spent fuel and defense high-level waste as provided under the Nuclear Waste Policy Act of 1982 and the 1987 amendments. The transport of spent fuel is expected to be accomplished by rail from 19 of the South`s 27 reactor sites to the proposed Yucca Mountain repository or possible monitored retrievable storage facility. The decline in total track availability, however, could significantly impact the federal government`s transportation program. Particularly the situation of continuing abandonments may limit rail opportunities at numerous reactor locations. Commercial nuclear reactor sites have the unfortunate problem of not being located on Class I railroad mainline tracks. The reactor sites are generally located in areas with limited rail traffic and thus vulnerable to rail abandonment procedures. The general deregulation of the railroad industry under the Staggers Act of 1980 also assisted in making rail abandonment, through the Interstate Commerce Commission, a rather simple and quick process. The effects of deregulation, however, have provided alternatives to abandonment. In particular, the Staggers Act has led to an enormous surge in the growth of short line and regional railroads. Such railroads have been able to effectively operate rail lines which Class I railroads found unprofitable. The short lines and regionals were also encouraged to competitively negotiate contracts directly with shippers. While these railroads may help reduce the number of abandonment applications, they may also represent higher shipping costs. The South has experienced a great number of abandonments since the 1960`s. Many of the abandonments have been significant in length and have affected areas near nuclear plants expected to ship by rail.
Date: February 1, 1988
Partner: UNT Libraries Government Documents Department

Mapping our genes: federal genome projects: How vast? How fast?: contractor reports, volume 2

Description: This report discusses the research and technology efforts aimed at mapping and sequencing large portions or entire genomes. It includes the implication of technologies, social and ethical issues, applications in research biology and medicine etc.
Date: February 1988
Creator: United States. Congress. Office of Technology Assessment
Partner: UNT Libraries Government Documents Department

Mapping our genes: federal genome projects: How vast? How fast?: contractor reports, volume 1

Description: This report discusses the research and technology efforts aimed at mapping and sequencing large portions or entire genomes. It includes the implication of technologies, social and ethical issues, applications in research biology and medicine etc.
Date: February 1988
Creator: United States. Congress. Office of Technology Assessment
Partner: UNT Libraries Government Documents Department

A note on the strengths and weaknessess [sic] of using the CPS to estimate children's health insurance coverage

Description: This report discusses the strengths and weaknesses of the Current Population Survey (CPS) relative to the National Health Interview Survey (NHIS), the National Medical Care Expenditure Survey (NMCE), for the purpose of estimating the numbers of children with different types of health insurance.
Date: February 1988
Creator: Swartz, Katherine
Partner: UNT Libraries Government Documents Department

Direct catalytic conversion of methane and light hydrocarbon gases. Quarterly report No. 5, November 16, 1987--January 15, 1988

Description: The goal of this research is to develop catalysts that directly convert methane and light hydrocarbons to intermediates that later can be converted to either liquid fuels or value-added chemicals, as economics dictate. During this reporting period, we have synthesized and tested several novel catalysts for methane reforming (Tasks 1 and 2) and for partial oxidation of methane (Tasks 3 and 4). We started to test a mixed metal system, an FeRu{sub 3} cluster. This catalyst was supported both on zeolite and on magnesium oxide and the systems were tested for methane reforming at various reaction temperatures. We also prepared and tested a monomeric ruthenium catalyst supported on magnesium oxide. We found that methane is activated at a lower temperature with the basic magnesium oxide support than with acidic supports such as zeolite or alumina. Methane conversions increased with temperature, but the production of coke also increased. We prepared a sterically hindered ruthenium porphyrin encapsulated in a zeolite supercage for catalysis of methane oxidation. The results showed that only carbon dioxide was produced. Addition of axial base to this catalyst gave similar results. Another type of catalyst, cobalt Schiff base complexes, was also prepared and tested for methane oxidation. In this case, no methane conversion was observed at temperatures ranging from 200 to 450{degrees}C. These complexes do not appear to be stable under the reaction conditions.
Date: February 5, 1988
Creator: Wilson, R.B. Jr. & Wai, Chan Yee
Partner: UNT Libraries Government Documents Department