We discuss the reliability of a recent global nuclear-structure calculation in regions far from {beta} stability. We focus on the results for nuclear masses, but also mention other results obtained in the nuclear-structure calculation, for example ground-state spins. We discuss what should be some minimal requirements of a nuclear mass model and study how the macroscopic-microscopic method and other nuclear mass models fullfil such basic requirements. We study in particular the reliability of nuclear mass models in regions of nuclei that were not considered in the determination of the model parameters.

A comparative generic accident analysis was performed for the programmatic alternatives for high-level waste (HLW) management in the US Department of Energy Environmental Restoration and Waste Management Programmatic Environmental Impact Statement (EM PEIS). The key facilities and operations of the five major HLW management phases were considered: current storage, retrieval, pretreatment, treatment, and interim canister storage. A spectrum of accidents covering the risk-dominant accidents was analyzed. Preliminary results are presented for HLW management at the Hanford site. A comparison of these results with those previously advanced shows fair agreement.

Regular hard disk backups for workstations are widely recommended. The necessity of backups -- akin to one`s own mortality -- is something most people would rather not think about. This attitude has two consequences. When people do subscribe to automated network backups, they expect the system to perform at a high level of reliability and that their files will be there for them when they need them. Second, they usually fail to appreciate that reliability is a shared responsibility. Although ostensibly their only responsibility is to keep the computer powered on overnight, there are actually many more opportunities for failure within the user`s jurisdiction than in other parts of the infrastructure. High reliability is almost a sine qua non for backups. We describe a strategy for enhancing reliability based on the principle of accountability. This strategy involves monitoring the system, gathering statistics, detecting problems, anticipating problems, troubleshooting, and finally determining where failure occurred within the infrastructure and who should be accountable. We describe a specific backup system in a specific network environment to illustrate the value of accountability. This system, macdumps, backs up Macintosh disks over an AppleTalk network. The original software was written by Dan Tappan of BBN in …

The microbial remediation of sites Contaminated with organics is well documented, however, there are some significant problems that remain to be solved in the areas of contaminants sorbed to soils and non-aqueous phase liquid (NAPL) contamination. Methods of in situ bioremediation techniques employ either the stimulation of indigenous populations by nutrient addition, or the addition of prepared bacterial cultures to the subsurface environment. Problems of contaminant sorption and NAPL`s are related in that both encompass reduced contaminant bioavailability. Non-aqueous phase liquids have been identified as a priority area for research in the In situ Program due to their presence at DOE sites and the lack of adequate technology to effectively treat this contamination. Bioremediation technologies developed as a result of this project are easily transferred to industry.

We are developing a set of tools to be used by the Safeguards Assay Group to solve problems found in safeguards and the domestic nuclear industry. The tools are also applicable to problems dealing with the environment, defense, and other areas of national and international interest. We have used extensively the advances in hardware and software since our last multichannel analyzer (MCA) development activities over a decade ago. We are also using our experience with and feedback from users of our previous instruments. In analyzing the instrument needs of our constituents and the characteristics of our previous instruments, which we think have inhibited their broader use, we have concluded that uses for an MCA-type instrument are widely varied and fundamentally changing,and that any new instruments should include a versatile, widely used hardware interface, which is as independent as possible of hardware standards, and which is readily interfaced to the computers or controllers rapidly evolving in the commercial sector. In addition, software tools must be provided that allow Los Alamos, users, and third parties to quickly and conveniently develop software specific to the user or the measurement to control the basic instrument we develop. This paper deals mainly with a miniature …

Passive neutron and other nondestructive assay techniques have been used extensively by the International Atomic Energy Agency to verify plutonium metal, powder, mixed oxide, pellets, rods, assemblies, scrap, and liquids. Normally, the coincidence counting rate is used to measure the {sup 240}Pu-effective mass and gamma-ray spectrometry or mass spectrometry is used to verify the plutonium isotopic ratios. During the past few years, the passive neutron detectors have been installed in plants and operated in the unattended/continuous mode. These radiation data with time continuity have made it possible to use the totals counting rate to monitor the movement of nuclear material. Monte Carlo computer codes have been used to optimize the detector designs for specific applications. The inventory sample counter (INVS-III) has been designed to have a higher efficiency (43%) and a larger uniform counting volume than the original INVS. Data analyses techniques have been developed, including the ``known alpha`` and ``known multiplication`` methods that depend on the sample. For scrap and other impure or poorly characterized samples, we have developed multiplicity counting, initially implemented in the plutonium scrap multiplicity counter. For large waste containers such as 200-L drums, we have developed the add-a-source technique to give accurate corrections for the …

The increasing complexity of integrated circuits demands that software tools, in addition to hardware tools, be used for successful diagnosis of failure. A series of customizable software tools have been developed that organize failure analysis information and provide expert level help to failure analysts to increase their productivity and success.

Progress has been made in recent years in the science of maceral separation. However, there are many areas that can be improved and new areas investigated. Power of density gradient centrifugation to physically resolve macerals and submaceral species coupled with other instrumental techniques is attractive for defining the limits of coal heterogeneity as well as investigating the ability of other separation methods.

The measurement of layer-to-layer feature overlay will, in the foreseeable future, continue to be a critical metrological requirement for the semiconductor industry. Meeting the image placement metrology demands of accuracy, precision, and measurement speed favors the use of electrical test structures. In this paper, a two-dimensional, modified voltage-dividing potentiometer is applied to a short-loop VLSI process to measure image placement. The contributions of feature placement on the reticle and overlay on the wafer to the overall measurement are analyzed and separated. Additional sources of uncertainty are identified, and methods developed to monitor and reduce them are described.

The Intelligent Manufacturing Systems (IMS) Test Case 6 project (Rapid Product Development) was set up to demonstrate rapid product development and 3D measurement techniques where the agencies performing the work were distributed over different countries. Test Case 6 provided a unique opportunity to examine the process by which an application protocol (AP) of the Standard for Exchange of Product Data is prepared. The test case had a well defined scope, the production of simple parts by means of layered manufacturing techniques. The information concerned with this manufacture was similarly well defined, due to the requirement that the information be transmitted among the organizations participating in the test case. STEP is an international standard specifying the data content and format for storage and exchange of product data throughout the product`s life cycle. STEP has been under development since 1984 and is just now emerging as an International Standard. STEP is specified as a series of information models using the EXPRESS computer language. For purposes of data exchange, a mapping to a physical file format is specified. Informally, product data can be defined as all the data about a product which one might wish to save. This definition implies some variation in …

Traditional alpha-particle detectors are limited by relatively poor sensitivity, small size, and difficulty of operation. These factors result in laborious effort and imprecise results. In addition, it is difficult for these detectors to monitor the inside of pipes and large areas having nonuniform surfaces. To be effective, traditional monitors require the probe to be held less than 1 cm from the surface while scanning with a slow, steady, and continuous motion. Long-range alpha detector (LRAD) technology overcomes the limitations imposed by the short range of alpha particles and provides a detailed analysis of alpha contamination in a cost-effective manner. Using a combination of LRAD airflow and electrostatic methods, we have developed several monitors for the detection of alpha contamination on hands and arms, in surface soil, and for radon gas.

This paper describes an approach for systematic evaluation of management alternatives that are being considered for the treatment, storage, and disposal of transuranic waste (TRUW) at U.S. Department of Energy sites. The approach, which is currently under development, would apply WASTE-MGMT, a database application model developed at Argonne National Laboratory, to estimate projected environmental releases and would evaluate impact measures such as health risk and costs associated with each of the waste management alternatives. The customized application would combine site-specific TRUW inventory and characterization data with treatment and transportation parameters to estimate the quantities and characteristics of the wastes to be treated, emissions of hazardous substances from the treatment facilities, and the quantities and characteristics of the wastes to be shipped between sites. These data would then be used to estimate for several TRUW management scenarios the costs and health risks of constructing and operating the required treatment facilities and of transporting TRUW for treatment and final disposal. Treatment, storage, and disposal of TRUW at DOE sites is composed of many variables and options at each stage. The approach described in this paper would provide for efficient consideration of all of these facets when evaluating potentially feasible TRUW management alternatives. …

The aqueous biphasic separation (ABS) process, which involves the selective partitioning of ultrafine particles or solutes between two immiscible aqueous phases, is being evaluated for removing uranium from contaminated clay soils. Goal is to remove ultrafine U from the soil, leaving residues below regulatory cleanup limits. Tests were made using U-contaminated soil near the Fernald waste incinerator; over 80% of the soil is <45 {mu}m. All the biphasic systems used polyethylene glycol in combination with inorganic salt phase. Results: U was reduced from 500--600 mg/kg to about 90 mg/kg, and in some cases even down to 15 mg/kg. However, a soil sample from the Fernald storage pad area did not give encouraging results. Selective flocculation of soil particles and dissolution of U in the salt phase occurred but were not troublesome. Scaleup tests using uncontaminated clay mineral feed were successful. Operating costs for soil remediation using ABS is estimated to be $25--50 per ton. A pilot-scale column is being installed at ANL.

Smart card systems are most cost efficient when implemented as a distributed system, which is a system without central host interaction or a local database of card numbers for verifying transaction approval. A distributed system, as such, presents special card and user authentication problems. Fortunately, smart cards offer processing capabilities that provide solutions to authentication problems, provided the system is designed with proper data integrity measures. Smart card systems maintain data integrity through a security design that controls data sources and limits data changes. A good security design is usually a result of a system analysis that provides a thorough understanding of the application needs. Once designers understand the application, they may specify authentication techniques that mitigate the risk of system compromise or failure. Current authentication techniques include cryptography, passwords, challenge/response protocols, and biometrics. The security design includes these techniques to help prevent counterfeit cards, unauthorized use, or information compromise. This paper discusses card authentication and user identity techniques that enhance security for microprocessor card systems. It also describes the analysis process used for determining proper authentication techniques for a system.

The high cost of optoelectronic (OE) devices is due mainly to the labor-intensive packaging process. Manually pigtailing such devices as single-mode laser diodes and modulators is very time consuming with poor quality control. The Photonics Program and the Engineering Research Division at LLNL are addressing several issues associated with automatically packaging OE devices. A furry automated system must include high-precision fiber alignment, fiber attachment techniques, in-situ quality control, and parts handling and feeding. This paper will present on-going work at LLNL in the areas of automated fiber alignment and fiber attachment. For the fiber alignment, we are building an automated fiber pigtailing machine (AFPM) which combines computer vision and object recognition algorithms with active feedback to perform sub-micron alignments of single-mode fibers to modulators and laser diodes. We expect to perform sub-micron alignments in less than five minutes with this technology. For fiber attachment, we are building various geometries of silicon microbenches which include on-board heaters to solder metal-coated fibers and other components in place; these designs are completely compatible with an automated process of OE packaging. We have manually attached a laser diode, a thermistor, and a thermo-electric heater to one of our microbenches in less than 15 minutes …

Automated target recognition software has been designed to perform image segmentation and scene analysis. Specifically, this software was developed as a package for the Army`s Minefield and Reconnaissance and Detector (MIRADOR) program. MIRADOR is an on/off road, remote control, multi-sensor system designed to detect buried and surface-emplaced metallic and non-metallic anti-tank mines. The basic requirements for this ATR software were: (1) an ability to separate target objects from the background in low S/N conditions; (2) an ability to handle a relatively high dynamic range in imaging light levels; (3) the ability to compensate for or remove light source effects such as shadows; and (4) the ability to identify target objects as mines. The image segmentation and target evaluation was performed utilizing an integrated and parallel processing approach. Three basic techniques (texture analysis, edge enhancement, and contrast enhancement) were used collectively to extract all potential mine target shapes from the basic image. Target evaluation was then performed using a combination of size, geometrical, and fractal characteristics which resulted in a calculated probability for each target shape. Overall results with this algorithm were quite good, though there is a trade-off between detection confidence and the number of false alarms. This technology also …

We identify a general framework for weak planning called bootstrap planning, which is defined as global planning using only a local planner along with some memory for learning intermediate subgoals. We present a family of algorithms for bootstrap planning, and provide some initial theory on their performance. In our theoretical analysis, we develop a random digraph problem model and use it to make some performance predictions and comparisons of these algorithms. We also use it to provide some techniques for approximating the optimal resource bound on the local planner to achieve the best global planner. We validate our theoretical results with empirical demonstration on the 15-puzzle. We show how to reduce the planning cost of a global planner by 2 orders of magnitude using bootstrap planning. We also demonstrate a natural but not widely recognized connection between search costs and the lognormal distribution.

The author begins with a brief synopsis about Hamiltonian systems and symplectic maps. A symplectic integrator is a symplectic map {phi}(q,p;t) that systematically approximates the time t flow of a Hamiltonian system. Systematic means: (1) in time step, t, i.e. the error should vanish as some power of the time step, and (2) in order of approximation, i.e. one would like a hierarchy of such {phi} that have errors that vanish as successively higher powers of the time step. At present the authors known two general types of symplectic integrators: (1) implicit integrators that are derived from a generating function or from algebraic conditions on Runge-Kutta schemes, and (2) explicit integrators that are derived from integrable Hamiltonians or from algebraic conditions on Runge-Kutta schemes.

Magnetization hysteresis loops have been studied over a wide range of field and temperature for a single crystal of Y-124 in order to look for scaling in characteristic fields of the loops. A multivalued magnetization curve in the shape of ``butterfly`` is observed with characteristic minimum fields, H{sub max}, and maximum fields, H{sub max}, that change systematically with temperature. H{sub max} varies as (1-T/T{sub c}) {sup alpha} where {alpha} is close to 1.5. On a reduced scale, H{sub max} for this Y-124 sample is very similar to several Y-124 sample is very similar to several Y-123 samples, suggesting that the origin of this effect is the same in these two systems. H{sub min} is exponential in temperature.

Based on screening transformations of muffin-tin orbitals introduced by Andersen et al. [Phys. Rev. Lett. 53, 2571 (1984)], we have developed a formalism for calculating the non-spherically averaged charge densities of substitutionally disordered alloys using the Korringa-Kohn-Rostoker coherent potential approximation (KKR CPA) method in the atomic-sphere approximation (ASA). We have validated our method by calculating charge densities for ordered structures, where we find that our approach yields charge densities that are essentially indistinguishable from the results of full-potential methods. For substitutionally disordered alloys, where full-potential methods have not been implemented so far, our approach can be used to calculate reliable non-spherically averaged charge densities from spherically symmetric one-electron potentials obtained from the KKR-ASA CPA. We report on our study of differences in charge denisty between ordered AlLi in L1{sub o} phase and substitutionally disordered Al{sub 0.5}Li{sub 0.5} on face-centered cubic lattice.

The quadrupole strengths, beam position monitor (BPM) gains, and orbit correction magnet strengths were adjusted in a computer model of the NSLS X-Ray ring in order to best fit the model orbit response matrix to the measured matrix. The model matrix was fit tot the 4320 data points in the measured matrix with an rms difference of only 2 to 3 microns, which is due primarily to noise in the BPM measurements. The strengths of the 56 individual quadrupoles in the X-Ray ring were determined to an accuracy of about 0.2%. The BPM and orbit corrector calibrations were also accurately determined. A through analysis of both random and systematic errors is included.

The second major run of the {bar p}p Fermilab Tevatron Collider ended on May 30. The CDF detector has accumulated almost five times the data sample of its previous 1988-1989 run. The author presents new results on electroweak physics, including the ratio of W to Z boson production cross-sections, and the charge asymmetry in W decay. He gives a progress report on the measurement of the W mass. New results from the 1988-1989 data on W-{gamma} production are also presented. The status of the search for the top quark in the dilepton modes is described. In addition a status report of the ongoing search in the lepton + jets mode is given.

In 1989, shortly after Westinghouse Hanford Company (WHC) assumed maintenance responsibilities for the Hanford site, a Department of Energy (DOE) maintenance audit found that field (working level) maintenance procedures and procedure practices of the facilities scattered across Hanford`s 560 square miles varied as greatly as the locations of those facilities. In some of the audited facilities there were few or no procedures; in others, procedures conflicted with or were redundant to procedures at other facilities. This document presents current efforts to centralize maintenance procedures.

Several general trends were observed in reactivity patterns of sulfur compounds in macerals. Sulfur is reduced in the asphaltene fraction compared to initial maceral. Aliphatics are removed and polycyclic aromatic compounds are both stable and probably formed under these conditions. Molecules containing two sulfur atoms are formed. The preasphaltenes are now being analyzed by DEIHRMS.