Parameterization of cumulus convection in general circulation model (GCM) has been recognized as one of the most important and complex issues in the model physical parameterizations. In earlier studies, most cumulus parameterizations were developed and evaluated using data observed over tropical oceans, such as the GATE (the Global Atmospheric Research Program's Atlantic Tropical Experiment) data. This is partly due to inadequate field measurements in the midlatitudes. In this study, we compare and evaluate a total of eight types of the state-of-the-art cumulus parameterizations used in fifteen Single-Column Models (SCM) under the summertime midlatitude continental conditions using the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) summer 1997 Intensive Operational Period (IOP) data, which covers several continental convection events. The purpose is to systematically compare and evaluate the performance of these cumulus parameterizations under summertime midlatitude continental conditions. Through the study we hope to identify strengths and weaknesses of these cumulus parameterizations that will lead to further improvements. Here, we briefly present our most interesting results. A full description of this study can be seen in Xie et al. (2001). The authors conclude that: (1) The SCM simulation errors are closely related to problems with model cumulus parameterizations. The schemes with …

Parameterization of cumulus convection in general circulation model (GCM) has been recognized as one of the most important and complex issues in the model physical parameterizations. In earlier studies, most cumulus parameterizations were developed and evaluated using data observed over tropical oceans, such as the GATE (the Global Atmospheric Research Program's Atlantic Tropical Experiment) data. This is partly due to inadequate field measurements in the midlatitudes. In this study, we compare and evaluate a total of eight types of the state-of-the-art cumulus parameterizations used in fifteen Single-Column Models (SCM) under the summertime midlatitude continental conditions using the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) summer 1997 Intensive Operational Period (IOP) data, which covers several continental convection events. The purpose is to systematically compare and evaluate the performance of these cumulus parameterizations under summertime midlatitude continental conditions. Through the study we hope to identify strengths and weaknesses of these cumulus parameterizations that will lead to further improvements. Here, we briefly present our most interesting results. A full description of this study can be seen in Xie et al. (2001).

This work addresses specification and design of reliable safety-critical systems, such as nuclear reactor control systems. Reliability concerns are addressed in complimentary fashion by different fields. Reliability engineers build software reliability models, etc. Safety engineers focus on prevention of potential harmful effects of systems on environment. Software/hardware correctness engineers focus on production of reliable systems on the basis of mathematical proofs. The authors think that correctness may be a crucial guiding issue in the development of reliable safety-critical systems. However, purely formal approaches are not adequate for the task, because they neglect the connection with the informal customer requirements. They alleviate that as follows. First, on the basis of the requirements, they build a model of the system interactions with the environment, where the system is viewed as a black box. They will provide foundations for automated tools which will (a) demonstrate to the customer that all of the scenarios of system behavior are presented in the model, (b) uncover scenarios not present in the requirements, and (c) uncover inconsistent scenarios. The developers will work with the customer until the black box model will not possess scenarios (b) and (c) above. Second, the authors will build a chain of several …

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Searches for the top quark in p{bar p} collisions at {radical}s = 1.8 TeV are described. The analyses are based on data with an integrated luminosity of 4.4 pb{sup {minus}1} recorded with the Collider Detector at Fermilab in the 1988--1989 run. An upper limit on the t{bar t} cross section is obtained. The top quark with mass below 89 GeV/c{sup 2} is excluded at the 95% CL. Prospects for searches for the top quark in the future are presented. We also briefly present results on searches for supersymmetric particles. 14 refs., 10 figs.

In the present reporting period, the first quarter of calendar year 1993, the effort was divided between Task 2. ``Pre Systems Tests`` and Task 4 ``Economics and Commercialization Plan.`` A major part of the task 2 effort was devoted converting the nozzle from adiabatic to air cooted operation. This conversion will allow immediate implementation of the longer duration task 3.2 tests after the completion of the task 2 tests. Therefore, a significant pan of the exit nozzle conversion effort is also part of task 3.1, ``Combustor Refurbishment.`` In task 1 the only activity remaining is to receive the results of the BYU combustion modeling. The results are anticipated this Spring. One of the three remaining tests in task 2 was implemented in late January under freezing weather and snow conditions. Ice plugged the coal feed lines and stack scrubber water outlet and ice jammed and damaged the coal metering auger. While these lines were thawed, the combustor was fired with oil. The coal used in this test contained fine fibrous tramp material which passed through the two tramp material retaining screens and eventually plugged several of the coal feed lines to the combustor. This cut the planned coal feed rate …

High salinity is one of the most common environmental stressors. In order to understand how environmental organisms adapt to salty environment, an experiment evolution with sulfate reducing bacteria Desulfovibrio vugaris Hildenborough was conducted. Control lines and salt-stressed lines (6 lines each) grown in minimal medium LS4D or LS4D + 100 mM NaCl were transferred for 1200 generations. The salt tolerance was tested with LS4D supplemented with 250 mM NaCl. Statistical analysis of the growth data suggested that all lines adapted to their evolutionary environment. In addition, the control lines performed better than the ancestor with faster growth rate, higher biomass yield and shorter lag phase under salty environment they did not evolve in. However, the salt-adapted lines performed better than the control lines on measures of growth rate and yield under salty environment, suggesting that the salt?evolved lines acquired mutations specific to having extra salt in LS4D. Growth data and gene transcription data suggested that populations tended to improve till 1000 generations and active mutations tended to be fixed at the stage of 1000 generations. Point mutations and insertion/deletions were identified in isolated colonies from salt-adapted and control lines via whole genome sequencing. Glu, Gln and Ala appears to be …

Short beam usage times were encountered using a 60 keV electron beam welder. These short times were the direct result of a buildup of a reaction product (WO/sub 2/./sub 90/) that occurred on graphite washers which housed the tungsten emitter plate. While it was not possible to prevent the reaction product, its growth rate was sufficiently altered by changing graphite materials and minor design changes of the washers. With these modifications beam usage times increased from an original 40 min to approximately 675 min.

We describe the scientific motivation for a new type of accelerator, the muon collider. This accelerator would permit an energy-frontier scientific program and yet would fit on the site of an existing laboratory. Such a device is quite challenging, and requires a substantial R&D program. After describing the ingredients of the facility, the ongoing R&D activities of the Muon Accelerator Program are discussed. A possible U.S. scenario that could lead to a muon collider at Fermilab is briefly mentioned.

A Neutrino Factory requires an intense and well-cooled (in transverse phase space) muon beam. We discuss a hybrid approach for a linear 4D cooling channel consisting of high-pressure gas-filled RF cavities--potentially allowing high gradients without breakdown--and discrete LiH absorbers to provide the necessary energy loss that results in the required muon beam cooling. We report simulations of the channel performance and its comparison with the vacuum case; we also briefly discuss technical and safety issues associated with cavities filled with high-pressure hydrogen gas. Even with additional windows that might be needed for safety reasons, the channel performance is comparable to that of the original, all-vacuum Feasibility Study 2a channel on which our design is based. If tests demonstrate that the gas-filled RF cavities can operate effectively with an intense beam of ionizing particles passing through them, our approach would be an attractive way of avoiding possible breakdown problems with a vacuum RF channel.

Three peaks and two dips have been detected in the power spectrum of the cosmic microwave background from the BOOMERANG experiment, at {ell} {approx} 210, 540, 840 and {ell} {approx} 420, 750, respectively. Using model-independent analyses, we find that all five features are statistically significant and we measure their location and amplitude. These are consistent with the adiabatic inflationary model. We also calculate the mean and variance of the peak and dip locations and amplitudes in a large 7-dimensional parameter space of such models, which gives good agreement with the model-independent estimates, and forecast where the next few peaks and dips should be found if the basic paradigm is correct. We test the robustness of our results by comparing Bayesian marginalization techniques on this space with likelihood maximization techniques applied to a second 7-dimensional cosmological parameter space, using an independent computational pipeline, and find excellent agreement: {Omega}{sub tot} = 1.02{sub -0.05}{sup +0.06} vs. 1.04 {+-} 0.05, {Omega}{sub b}h{sup 2} = 0.022{sub -0.003}{sup +0.004} vs. 0.019{sub -0.004}{sup +0.005}, and n{sub s} = 0.96{sub -0.09}{sup +0.10} vs. 0.90 {+-} 0.08. The deviation in primordial spectral index n{sub s} is a consequence of the strong correlation with the optical depth.

Objective of this audit was to determine whether the Mound Plant`s Fiscal Year 1992 reduction in force (RIF) was effectively managed and implemented properly by DOE. DOE established policy to encourage contractors to reduce staffing by voluntary separations without unreasonable separation costs. EG&G Mound`s FY 1992 RIF was accomplished by voluntary separations; however, its implementation unreasonably increased costs because DOE did not have adequate criteria or guidelines for evaluating contractors` RIF proposals, and because EG&G Mound furnished inaccurate cost data to DOE evaluators. The unreasonable costs amounted to at least $21 million. Recommendations are made that DOE develop and implement guidelines to impose limitations on voluntary separation allowances, early retirement incentive payments, and inclusion of crucial employee classifications in voluntary RIFs.

This document is an end-of-contract report, prepared by Hydro Geo Chem for Los Alamos National Laboratory under contract number 9-XDD-6329F-1. The ultimate goal of this work is to characterize historical infiltration and unsaturated flow in the Yucca Mountain area of the Nevada Test Site. Work on this contract has focused on using chloride, bromide, stable chlorine isotopes, and chlorine-36 distributions to evaluate the depth of infiltration in the unsaturated zone. Effort in support of this work has included developing analytical procedures, exploring ways in which to separate the. meteoric component from the rock component, and meeting quality assurance requirements.

We have constructed an anatomically correct human geometry, which can be used to store radioisotope concentrations in 51 various internal organs. Each organ is associated with an index number which references to its attenuating characteristics (composition and density). The initial development of Computer Simulated Images of Radiopharmaceuticals in Anthropomorphic Phantoms (CSIRDAP) over the first 3 years has been very successful. All components of the simulation have been coded, made operational and debugged.

We have constructed an anatomically correct human geometry, which can be used to store radioisotope concentrations in 51 various internal organs. Each organ is associated with an index number which references to its attenuating characteristics (composition and density). The initial development of Computer Simulated Images of Radiopharmaceuticals in Anthropomorphic Phantoms (CSIRDAP) over the first 3 years has been very successful. All components of the simulation have been coded, made operational and debugged.

The Pebble-Bed Reactor Experiment (PBRE) was designed to advance the pebble-bed concept by providing a test of characteristic features and make contriliutions to the general development of all-ceramic gas-cooled reactors. The following objectives were established for the reactor experiment: to investigate key features of the pebble-bed concept, including on-stream fuel handling, movement of fuel through bed, and performance of core; to obtain operation and maintenance experience with a system contaminated with fission- product activity; and to investigate the behavior of graphite fuel elements. A fourth objective, study of the behavior of core materials at conditions occurring with exit gas temperatures in the range 2000 to 2500 deg F, was tentatively included. The preliminary design oE a 5-Mw(t) reactor for achieving these objectives was prepared. The core of the PBRE is a 2 1/2-ft-diam, 4-ft-tall cylinder containing approximately 12,000 spherical graphite fuel elements 1 1/2 in. in diameter. Fuel spheres are added to and removed from the core by gravity flow, and these operations are performed while the reactor is at power by using pairs of valves for passage of elements into and out of the high-pressure system. Exposed fuel can be recycled to the top of the core. Helium coolant …

This publication disseminates information on progress in various DOE research areas. This issues contains information on Longwall mining; electric fleet utility survey; electronic publishing system; other publications of the EIA; and places from which to purchase publications.

Work continued as planned and scheduled. Total expenditures are below budget. Tasks 2 and 3 are complete. Task 5 was started early. Task 6 will start in April. The following major deliverables were issued: (1) Slides and narrative for PETC Audio/Visual combustion 2000 Exhibit; (2) Technical Paper for the 19th International Technical Conference on Coal Utilization & Fuel Systems; and (3) Draft of Technical Paper (for internal review) for the 1994 International Joint Power Generation Conference. Two advisors were added to the Team -- Richmond Power & Light and Peridot chemicals, Inc. RP&L is an excellent candidate for the POC host. Peridot has expertise in the production and marketing of sulfuric acid. A regular Quarterly Review Meeting was held with DOE-PETC.

The project is on schedule and under budget. The current status is shown in the Milestone Schedule Report included as Appendix A. All Project Plans were updated based on the revised finding level authorized for FY95 and anticipated for FY96. Technology Transfer activities included {open_quotes}supplying{close_quotes} three executives and several team members to the LEBS Workshop, delivering a technical paper at a conference, and working on a Combustion 2000 Session for another conference. ABBES and CeraMem reached agreement concerning Task 7 work, including ownership and disposition of project-purchased equipment to be used during Task 7 and also during Task 11. A test plan was prepared. Task 7 activities for the Low-NO{sub x} Firing System included computational modeling of the firing arrangement. Reasonable comparisons to experimental data previously obtained in the Boiler Simulation Facility were achieved. A kinetic evaluation for both baseline and low NO{sub x} firing arrangements was also performed, with results indicating that the final reducing zone within the main windbox has a dominant effect on NO{sub x} reduction, with higher temperatures being more favorable for lower NO{sub x}. A week of combustion testing was completed in the Fundamental Scale Burner Facility to examine the impact of integrated fuel staging …

Inspection revealed that immediate management attention is needed to properly control, store, and dispose of excess personal property at Rocky Flats. Current system of operation does not allow for efficient, timely, cost effective management; current storage and disposal practices are not consistent with contract requirements or DOE policies and procedures. Other deficiencies are pointed out. Results of inspection are divided into 4 sections: contract changeover issues, moratorium issues, additional excess property issues, and award fee observations. Recommendations are outlined.

Crystal growth experiments were performed and growth of KTb/sub 3/F/sub 10/ crystals were accomplished. The crystal growth experiments consisted of hot zone modification and development of growth parameters. Several boules of KTb/sub 3/F/sub 10/ 30 to 40mm in diameter and one boule 50mm in diameter were grown at rates varying from .5mm/hr to 3.0mm/hr. The crystals evaluated display excellent optical quality. The optical path distortion was less than 0.5 fringe/cm at 633nm as viewed in Twyman--Green interferometry. Growth of large crystals has been limited by mechanical cleavage.

This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted by the Environmental Protection Department`s Environmental Monitoring Section (EPD/EMS) during the fourth quarter of 1992. It includes the analytical data, field data, data review, quality control, and other documentation for this program, provides a record of the program`s activities; and serves as an official document of the analytical results.

This report summarizes the activities of this grant during the second reporting period. During this period, several research activities concerning the synthesis and characterization of novel surfactants were performed. Of immediate interest was the investigation of surfactants identified in the first quarterly report, such as cetyltripropylammonium bromide and cetyltributylammonium bromide. These surfactants were of interest because of the low critical micelle concentration they exhibit.

The objectives of this report are to provide the necessary administrative support to assure that the scientific and educational goals of the project are obtained and to assure that all Department of Energy reporting requirements and requests are fulfilled. The grant reporting is divided into three aspects: Collaborative Cluster projects, Initiation projects and Education projects. A cluster project is one or more closely related collaborative, multidisciplinary research projects in which a group of investigators employs a synergistic approach to the solution of problems in the same general area of research. The accomplishments this quarter of eleven cluster projects are presented. An initial project typically involves a single investigator. The purpose of the project is to undertake pilot work, lasting no more than one year, which will lead to the successful submission of an externally-funded proposal or the development of a collaborative cluster project. The accomplishments this quarter of eleven initiation projects are presented. The education projects are designed to develop courses with emphasis on environmental studies and/or to train students in areas of environmental research.