A discrete event simulation model has been developed to predict the assembly flow time of a new radar product. The simulation was the key tool employed to identify flow constraints. The radar, production facility, and equipment complement were designed, arranged, and selected to provide the most manufacturable assembly possible. A goal was to reduce the assembly and testing cycle time from twenty-six weeks to six weeks. A computer software simulation package (SLAM II) was utilized as the foundation a for simulating the assembly flow time. FORTRAN subroutines were incorporated into the software to deal with unique flow circumstances that were not accommodated by the software. Detailed information relating to the assembly operations was provided by a team selected from the engineering, manufacturing management, inspection, and production assembly staff. The simulation verified that it would be possible to achieve the cycle time goal of six weeks. Equipment and manpower constraints were identified during the simulation process and adjusted as required to achieve the flow with a given monthly production requirement. The simulation is being maintained as a planning tool to be used to identify constraints in the event that monthly output is increased. ``What-if`` studies have been conducted to identify the …

No endeavor is risk-fire and as we realize the inherent risks in society, our only viable solution is to manage the risk. Application of an integrated risk management program of a large technological system like the DOE complex is a difficult, task; but it is the only rational means to optimize the risk-benefit equation. An effective risk management culture-within the DOE complex will in the long run, ensure a consistent response to mitigate identified risks. An effective risk management program provides responsible administrative planning and logical application of the best technical analyses. It requires the involvement of all personnel. Our objective in this paper is to point out broad perspectives that raise concerns about future DOE ask management issues and to suggest some possible remedies.

We investigate the suitability and effectiveness of iterative methods for solving the weighted-least-square (WLS) state estimation problem on RISC, vector, and parallel processors. Several of the most popular iterative methods are tested and evaluated. The best performing preconditioned conjugate gradient (PCG) is very well suited for vector and parallel processing as is demonstrated for the WLS state estimation of the IEEE standard test systems. A new sparse matrix format for the gain matrix improves vector performance of the PCG algorithm and makes it competitive to the direct solver. Internal parallelism in RISC processors, used in current multiprocessor systems, can be taken advantage of in an implementation of this algorithm.

Four wetland crossings of gas pipeline rights-of-way (ROWs), located in Florida, Michigan, New Jersey, and New York, were surveyed for generation of vegetation roughly one year after pipeline construction was completed. Conventional trench-and-fill construction techniques were employed for all four sites. Estimated areal coverage of each species by vegetative strata within transect plots was recorded for plots on the ROW and in immediately adjacent wetlands undisturbed by construction activities. Relative success of regeneration was measured by percent exposed soil, species diversity, presence of native and introduced species, and hydric characteristics of the vegetation. Variable site factors included separation and replacement of topsoil, final grading of the soil, application of seed and fertilizer, and human disturbance unrelated to construction. Successful regeneration exhibited greater dependency on the first three factors listed.

The spatial and temporal variations of local surface temperature and heat flux for saturated pool nucleate boiling are investigated parametrically using a numerical model. The numerical model consisted of solving the three-dimensional transient heat conduction equation within the heater subjected to nucleate boiling over its upper surface. The surface topography model to distribute the cavities over the boiling surface used a Monte Carlo scheme. All cavities were assumed to be conical in shape. The cavity radii are obtained using an exponential probability density function with a known mean value. Local surface temperatures showed significant spatial and temporal variations, depending upon the surface topography and the heater material and thickness. However, the surface-averaged temperature showed practically no temporal variation. The temporal variations in local temperatures caused the surface-averaged heat flux to vary significantly. The temporal variations in the surface-averaged heat flux were similar for smooth and rough and thick and thin copper and nickel plates. Results indicated that the use of a classical energy balance equation to evaluate the surface heat flux must consider the spatial variation of the temperature. Results also showed that any thermocouple embedded beneath the surface of the heater does not follow the temporal variations at the …

Based on a logistic regression approach, a model was developed using the explanatory variables log([NO{sub 3}{sup {minus}}]), log([NO{sub 2}{sup {minus}}]), and temperature to estimate the probability of pitting in a carbon steel exposed to high-level radioactive waste. Pitting susceptibility data obtained by the two techniques of cyclic potentiodynamic polarization and coupon immersion were separately and jointly analyzed with the model. Similar predictive ability is seen for equations based on both electrochemical and coupon immersion data. Using the theory associated with the determination of confidence intervals for the estimated probability, a methodology was developed to provide a lower bound for the nitrite concentration which inhibits pitting, i.e., which holds the estimated probability of pitting to a reasonably low level of 0.05.

The purpose of this work is to determine the feasibility of using Electrical resistance tomography (ERT) to nondestructively examine the interior of concrete structures such as bridge pillars and roadways. We report the results of experiments wherein ERT is used to image the two concrete specimens in the laboratory. Each specimen is 5 inches square and 12 inches long and contained steel reinforcing rods along its length. Twenty electrodes were placed on each sample and an-image of electrical resistivity distribution was generated from current and voltage measurements. We found that the images show the general location of the reinforcing steel and, what`s more important, delineate the absence of the steel. The method may therefore be useful for determining if such steel has been destroyed by corrosion, however to make it useful, the technique must have better resolution so that individual reinforcing steel units are resolved.

GlidCop{trademark} internally oxidized copper alloys remain the leading candidates for high heat flux applications in fusion reactor. This paper presents the microstructural changes incurred in three GlidCop{trademark} alloys exposed to long term, high temperature neutron irradiation. Irradiation at high temperature produced a microstructure containing a much lower dislocation density than the unirradiated specimens. Although 10--50 nm size triangular oxide particles were observed in areas with a very low number density of particles, spherical oxide particles on the order of 5--7 nm in diameter, thought to be CuAl{sub 2}O{sub 4}, were the predominant morphology. The changes in grain size distribution, dislocation density, and precipitate type and distribution saturate in the range of 34 to 50 dpa, as reflected in the saturation of mechanical properties.

The MELCOR Accident Consequence Code System (MACCS) has been applied to the radiological consequence assessment of potential accidents from a non-reactor nuclear facility. MACCS has been used in a variety of applications to evaluate radiological dose and health effects to the public from postulated plutonium releases and from postulated criticalities. These applications were conducted to support deterministic and probabilistic accident analyses for safety analyses for safety analysis reports, radiological sabotage studies, and other regulatory requests.

A Laser Control system has been built for the DIII-D Scattering Diagnostic. This new system has provided the capability to place the laser probe pulses with one microsecond timing precision throughout the DIII-D shot. The new system fires the eight lasers with a programmable sequence which repeats ever 50 ms. If one wants to probe the plasma at a higher rate to study a fast paced event, the new control circuit can fire all charged lasers in rapid succession (BURST MODE). This burst rate is programmable. The new Laser Control system successfully replaced the previous control scheme which consisted of three VME Motorola 68030 computers (one host under UNIX VME V/68 and two interrupt driven targets under VME Exec. The old system was not successful due to the many VME interrupts needed to service the lasers. The new hardware approach is much more reliable. The old system still controls data acquisition and as a monitoring system since it does not have the burden of controlling the lasers. A brief description of the Thomson Scattering diagnostic will be presented with emphasis in the new upgraded laser firing control system and data acquisition timing control.

Lactic acid has been an intermediate-volume specialty chemical (world production {approximately}40,000 tons/yr) used in a wide range of food processing and industrial applications. lactic acid h,as the potential of becoming a very large volume, commodity-chemical intermediate produced from renewable carbohydrates for use as feedstocks for biodegradable polymers, oxygenated chemicals, plant growth regulators, environmentally friendly ``green`` solvents, and specially chemical intermediates. In the past, efficient and economical technologies for the recovery and purification of lactic acid from crude fermentation broths and the conversion of tactic acid to the chemical or polymer intermediates had been the key technology impediments and main process cost centers. The development and deployment of novel separations technologies, such as electrodialysis (ED) with bipolar membranes, extractive distillations integrated with fermentation, and chemical conversion, can enable low-cost production with continuous processes in large-scale operations. The use of bipolar ED can virtually eliminate the salt or gypsum waste produced in the current lactic acid processes. In this paper, the recent technical advances in tactic and polylactic acid processes are discussed. The economic potential and manufacturing cost estimates of several products and process options are presented. The technical accomplishments at Argonne National Laboratory (ANL) and the future directions of this program …

To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine.

the clinical diagnosis of a lesion often requires that a histological analysis be made of a physical specimen of the suspect tissue. In the present work, the authors have utilized an optical biopsy system (OBS) developed at Los Alamos National Laboratory which is safe for patient use and provides a large amount of optical data from the sampled tissue. An earlier version of this system has been used to study age-related changes in the ocular lens (10). The purpose of the present study is to establish the potential clinical utility of the OBS by determining if characteristic features in the optical signatures, obtained from a variety of ophthalmic lesions, are correlated with the histological features of tissue biopsies obtained from these patients.

Glass produced during the Purex 4 campaigns of the Integrated DWPF Melter System (IDMS) and the 774 Research Melter contained a lower fraction of sludge components than targeted by the Product Composition Control System (PCCS). Purex 4 glass was more durable than the benchmark (EA) glass, but was less durable than most other simulated SRS high-level waste glasses. Further, the measured durability of Purex 4 glass was not as well correlated with the durability predicted from the DWPF process control algorithm, probably because the algorithm was developed to predict the durability of SRS high-level waste glasses with higher sludge content than Purex 4. A melter run, designated Purex 4 Remediation, was performed using the 774 Research Melter to determine if the initial PCCS target composition determined for Purex 4 would produce acceptable glass whose durability could be accurately modeled by the DWPF glass durability algorithm. Reagent grade oxides and carbonates were added to Purex 4 melter feed stock to simulate a higher sludge loading. Each canister of glass produced was sampled and the glass durability was determined by the Product Consistency Test method. This document details the durability data and subsequent analysis.

This paper presents test results of 610-mm wide (24-in.) by 1219-mm high (48-in.) by 203-or 330-mm (8- or 13-in.) thick prisms constructed of hollow clay tiles. Three prisms were extracted fro existing hollow clay title walls and 69 were constructed in laboratories at The University of Tennessee and the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland. Modulus of Elasticity, E, and compressive strength f{prime}{sub m} were calculated from the results.

We examine the issue of thermal interactions within a heater as a possible explanation for conflicting critical heat flux data on thin heaters, as reported by various investigators. While heater thermal properties have been considered in previous studies, the focus of this study is the interaction between the thermal transport process within the heater and the distribution of nucleation sites on the heater surface. It is shown that the spatial distribution of stems on the heater surface, as well as the size distribution of these stems, can affect the average surface temperatures. Such interactions are greater as the heater thickness decreases.

Poloidal and toroidal rotation of the fuel ions (He{sup 2+}) and the impurity ions (C{sup 6+} and B{sup 5+}) in H-mode helium plasmas have been investigated in the DIII-D tokamak by means of charge exchange recombination spectroscopy, resulting in the discovery that the fuel ion poloidal rotation is in the ion diamagnetic drift direction while the impurity ion rotation is in the electron diamagnetic drift direction. The radial electric field obtained from radial force balance analysis of the measured pressure gradients and rotation velocities is shown to be the same regardless of which ion species is used and therefore is a more fundamental parameter than the rotation flows in studying H-mode phenomena. It is shown that the three contributions to the radial electric field (diamagnetic, poloidal rotation, and toroidal rotation terms) are comparable and consequently the poloidal flow does not solely represent the E {times} B flow. In the high-shear edge region, the density scale length is comparable to the ion poloidal gyroradius, and thus neoclassical theory is not valid there. In view of this new discovery that the fuel and impurity ions rotate in opposite sense, L-H transition theories based on the poloidal rotation may require improvement.

Time-of-flight neutron powder diffraction was used to determine the Debve-Waller factors of light actinide metals. The Debye-Waller factor is a measure of the mean-square atomic displacement that arises from the thermal motion ofthe atoms in any solid. Its temperature dependence determines a Debye-Waller temperature, {Theta}{sub DW}, that is characteristic of the elastic properties of the solid. The data are obtained by Rietveld analysis of neutron diffraction powder patterns obtained at several temperatures. Results are presented for {alpha}-U, {alpha}-Np, {alpha}-Pu and {delta}-Pu{sub 0.95}Al{sub 0.05}. The {Theta}{sub DW}`s are temperature dependent, and anharmonic interatomic forces seem to be required to explain the results.

This report is the minutes of the Solar Working group. The meeting was prompted by the Steering Group`s desire to resolve issues the Solar Working Group.

This study examines the effects of global climate change on commercial building energy use. The methodology used included estimating balance points and degree-day response coefficients, estimating cross-section regressions to extrapolate to a full sample, extrapolating the building sample to the year 2030, and estimating the energy consumption in the year 2030 under different temperature regimes. Results show that total primary energy consumption in U.S. commercial buildings will rise although the absolute increase in consumption may not be large, given offsetting heating benefits. Nonetheless, the effect on electric utilities may be severe.

In many science and engineering applications, there is an interest in predicting the outputs of a process for given levels of inputs. In order to develop a model, one could run the process (or a simulation of the process) at a number of points (a point would be one run at one set of possible input values) and observe the values of the outputs at those points. There observations can be used to predict the values of the outputs for other values of the inputs. Since the outputs are a function of the inputs, we can generate a surface in the space of possible inputs and outputs. This surface is called a response surface. In some cases, collecting data needed to generate a response surface can e very expensive. Thus, in these cases, there is a powerful incentive to minimize the sample size while building better response surfaces. One such case is the semiconductor equipment manufacturing industry. Semiconductor manufacturing equipment is complex and expensive. Depending upon the type of equipment, the number of control parameters may range from 10 to 30 with perhaps 5 to 10 being important. Since a single run can cost hundreds or thousands of dollars, it …

The Advanced Light Source (ALS), under construction for the past seven years, has become operational. The accelerator has been successfully commissioned using a control system based on hundreds of controllers of our own design and high performance personal computers which are the operator interface. The first beamlines are being commissioned using a control system based on VME hardware and the Experimental Physics and Industrial Control System (EPICS) software. The two systems are being integrated, and this paper reports on the current work being done.

Moderation control is the basic parameter for ensuring nuclear criticality safety during the packaging and transport of low {sup 235}U enriched uranium hexafluoride before its conversion to nuclear power reactor fuel. Moderation control has permitted the shipment of bulk quantities in large cylinders instead of in many smaller cylinders and, therefore, has resulted in economies without compromising safety. Overall safety and uranium accountability have been enhanced through the use of the moderation control. This paper discusses moderation control and the operating procedures to ensure that moderation control is maintained during packaging operations and transportation.

Experimental research performed at the Pacific Northwest Laboratory relating to energy deposition by energetic charged particles is described. How cross section data obtained from gaseous- and condensed-phase studies are related to understanding damage to biomolecules is discussed. Studies to date stress the need for information about energy deposition in individual interactions and show that multiple ionization may play a very significant role in biological damage. Current efforts to relate this gas-phase information to condensed-phase processes and biologically relevant targets are outlined.