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At least 199 records · Page 11

District wide water resources investigation and management using LANDSAT data. Phase 1: Lake volume

A technique for estimating available water storage volume using LANDSAT data was developed and applied to Lake Washington and Lake Harris in central Florida. The technique can be applied two ways. First, where the historical stage records are available, the historical LANDSAT data can be used to establish the relationship between lake volume and lake stage. In the second case, where the historical stage records are not available, the historical LANDSAT data can be used to estimate the historical lake stage after the lake volume and stage information become available in the future.

Shih, S. F.↗

Budget estimates: Fiscal year 1994. Volume 2: Construction of facilities

The Construction of Facilities (CoF) appropriation provides contractual services for the repair, rehabilitation, and modification of existing facilities; the construction of new facilities and the acquisition of related collateral equipment; the acquisition or condemnation of real property; environmental compliance and restoration activities; the design of facilities projects; and advanced planning related to future facilities needs. Fiscal year 1994 budget estimates are broken down according to facility location of project and by purpose.

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Application of remotely sensed land-use information to improve estimates of streamflow characteristics, volume 8

The author has identified the following significant results. Land use data derived from high altitude photography and satellite imagery were studied for 49 basins in Delaware, and eastern Maryland and Virginia. Applying multiple regression techniques to a network of gaging stations monitoring runoff from 39 of the basins, demonstrated that land use data from high altitude photography provided an effective means of significantly improving estimates of stream flow. Forty stream flow characteristic equations for incorporating remotely sensed land use information, were compared with a control set of equations using map derived land cover. Significant improvement was detected in six equations where level 1 data was added and in five equations where level 2 information was utilized. Only four equations were improved significantly using land use data derived from LANDSAT imagery. Significant losses in accuracy due to the use of remotely sensed land use information were detected only in estimates of flood peaks. Losses in accuracy for flood peaks were probably due to land cover changes associated with temporal differences among the primary land use data sources.

Pluhowski, E. J.↗

Flow Loop Study of ECT-Based Volume Fraction Monitoring in Oil–Water Two-Phase Flows

Measurement of phase volume fractions in water-containing multiphase flows is necessary for the optimization of a host of industrial flow processes. Many water-containing multiphase flows can be classified as either water-dispersed or water-continuous mixtures. A recently developed approach based on Hanai’s mixture formula and utilizing electrical capacitance tomography (ECT) sensors have shown good potential for obtaining water volume fraction estimates in two-phase water-containing flows with different water salinity levels. However, the proposed approach was investigated via controlled experiments restricted to static configurations while, in practice, multiphase flows can be dynamic and unpredictable. In this work, we perform a flow loop study of the proposed ECT-based method for volume fraction estimation in oil–water two-phase flows. Here, we evaluate the performance of the proposed method in both water-dispersed and water-continuous flow regimes by employing different types of capacitive sensors in cylindrical arrangements and parallel-plate rectangular arrangements.

02 PETROLEUM↗

Budget estimates: Fiscal year 1994. Volume 1: Agency summary

The NASA FY 1994 budget request of $15,265 million concentrates on (1) investing in the development of new technologies including a particularly aggressive program in aeronautical technology to improve the competitive position of the United States, through shared involvement with industry and other government agencies; (2) continuing the nation's premier program of space exploration, to expand our knowledge of the solar system and the universe as well as the earth; and (3) providing safe and assured access to space using both the space shuttle and expendable launch vehicles. Budget estimates are presented for (1) research and development, including space station, space transportation capability development, space science and applications programs, space science, life and microgravity sciences and applications, mission to planet earth, space research and technology, commercial programs, aeronautics technology programs, safety and mission quality, academic programs, and tracking and data advanced systems; and (2) space operations, including space transportation programs, launch services, and space communications.

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Measuring Compositions in Organic Depth Profiling: Results from a VAMAS Interlaboratory Study

We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) interlaboratory study on the measurement of composition in organic depth profiling. Layered samples with known binary compositions of Irganox 1010 and either Irganox 1098 or Fmoc-pentafluoro-L-phenylalanine in each layer were manufactured in a single batch and distributed to more than 20 participating laboratories. The samples were analyzed using argon cluster ion sputtering and either X-ray Photoelectron Spectroscopy (XPS) or Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) to generate depth profiles. Participants were asked to estimate the volume fractions in two of the layers and were provided with the compositions of all other layers. Participants using XPS provided volume fractions within 0.03 of the nominal values. Participants using ToF-SIMS either made no attempt, or used various methods that gave results ranging in error from 0.02 to over 0.10 in volume fraction, the latter representing a 50% relative error for a nominal volume fraction of 0.2. Error was predominantly caused by inadequacy in the ability to compensate for primary ion intensity variations and the matrix effect in SIMS. Matrix effects in these materials appear to be more pronounced as the number of atoms in both the primary analytical ion and the secondary ion increase. Using the participants’ data we show that organic SIMS matrix effects can be measured and are remarkably consistent between instruments. We provide recommendations for identifying and compensating for matrix effects. Finally we demonstrate, using a simple normalization method, that virtually all ToF-SIMS participants could have obtained estimates of volume fraction that were at least as accurate and consistent as XPS.

Environmental Molecular Sciences Laboratory↗

Bayesian 3D X-ray computed tomography image reconstruction with a scaled Gaussian mixture prior model

In order to improve quality of 3D X-ray tomography reconstruction for Non Destructive Testing (NDT), we investigate in this paper hierarchical Bayesian methods. In NDT, useful prior information on the volume like the limited number of materials or the presence of homogeneous area can be included in the iterative reconstruction algorithms. In hierarchical Bayesian methods, not only the volume is estimated thanks to the prior model of the volume but also the hyper parameters of this prior. This additional complexity in the reconstruction methods when applied to large volumes (from 512{sup 3} to 8192{sup 3} voxels) results in an increasing computational cost. To reduce it, the hierarchical Bayesian methods investigated in this paper lead to an algorithm acceleration by Variational Bayesian Approximation (VBA) [1] and hardware acceleration thanks to projection and back-projection operators paralleled on many core processors like GPU [2]. In this paper, we will consider a Student-t prior on the gradient of the image implemented in a hierarchical way [3, 4, 1]. Operators H (forward or projection) and H{sup t} (adjoint or back-projection) implanted in multi-GPU [2] have been used in this study. Different methods will be evalued on synthetic volume 'Shepp and Logan' in terms of quality and time of reconstruction. We used several simple regularizations of order 1 and order 2. Other prior models also exists [5]. Sometimes for a discrete image, we can do the segmentation and reconstruction at the same time, then the reconstruction can be done with less projections.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Tug fleet and ground operations schedules and controls. Volume 3: Program cost estimates

Cost data for the tug DDT&E and operations phases are presented. Option 6 is the recommended option selected from seven options considered and was used as the basis for ground processing estimates. Option 6 provides for processing the tug in a factory clean environment in the low bay area of VAB with subsequent cleaning to visibly clean. The basis and results of the trade study to select Option 6 processing plan is included. Cost estimating methodology, a work breakdown structure, and a dictionary of WBS definitions is also provided.

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Laser Atmospheric Wind Sounder (LAWS) phase 1. Volume 3: Project cost estimates

The laser atmospheric wind sounder (LAWS) cost modeling activities were initiated in phase 1 to establish the ground rules and cost model that would apply to both phase 1 and phase 2 cost analyses. The primary emphasis in phase 1 was development of a cost model for a LAWS instrument for the Japanese Polar Orbiting Platform (JPOP). However, the Space Station application was also addressed in this model, and elements were included, where necessary, to account for Space Station unique items. The cost model presented in the following sections defines the framework for all LAWS cost modeling. The model is consistent with currently available detail, and can be extended to account for greater detail as the project definition progresses.

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Space Transportation Booster Engine Configuration Study. Volume 3: Program Cost estimates and work breakdown structure and WBS dictionary

The objective of the Space Transportation Booster Engine Configuration Study is to contribute to the ALS development effort by providing highly reliable, low cost booster engine concepts for both expendable and reusable rocket engines. The objectives of the Space Transportation Booster Engine (STBE) Configuration Study were: (1) to identify engine development configurations which enhance vehicle performance and provide operational flexibility at low cost; and (2) to explore innovative approaches to the follow-on Full-Scale Development (FSD) phase for the STBE.

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Orbital Spacecraft Consumables Resupply System (OSCRS). Volume 3: Program Cost Estimate

A cost analysis for the design, development, qualification, and production of the monopropellant and bipropellant Orbital Spacecraft Consumable Resupply System (OSCRS) tankers, their associated avionics located in the Orbiter payload bay, and the unique ground support equipment (GSE) and airborne support equipment (ASE) required to support operations is presented. Monopropellant resupply for the Gamma Ray Observatory (GRO) in calendar year 1991 is the first defined resupply mission with bipropellant resupply missions expected in the early to mid 1990's. The monopropellant program estimate also includes contractor costs associated with operations support through the first GRO resupply mission.

Perry, D. L.↗

Space Station Furnace Facility. Volume 3: Program cost estimate

The approach used to estimate costs for the Space Station Furnace Facility (SSFF) is based on a computer program developed internally at Teledyne Brown Engineering (TBE). The program produces time-phased estimates of cost elements for each hardware component, based on experience with similar components. Engineering estimates of the degree of similarity or difference between the current project and the historical data is then used to adjust the computer-produced cost estimate and to fit it to the current project Work Breakdown Structure (WBS). The SSFF Concept as presented at the Requirements Definition Review (RDR) was used as the base configuration for the cost estimate. This program incorporates data on costs of previous projects and the allocation of those costs to the components of one of three, time-phased, generic WBS's. Input consists of a list of similar components for which cost data exist, number of interfaces with their type and complexity, identification of the extent to which previous designs are applicable, and programmatic data concerning schedules and miscellaneous data (travel, off-site assignments). Output is program cost in labor hours and material dollars, for each component, broken down by generic WBS task and program schedule phase.

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Budget estimates, fiscal year 1995. Volume 1: Agency summary, human space flight, and science, aeronautics and technology

The NASA budget request has been restructured in FY 1995 into four appropriations: human space flight; science, aeronautics, and technology; mission support; and inspector general. The human space flight appropriations provides funding for NASA's human space flight activities. This includes the on-orbit infrastructure (space station and Spacelab), transportation capability (space shuttle program, including operations, program support, and performance and safety upgrades), and the Russian cooperation program, which includes the flight activities associated with the cooperative research flights to the Russian Mir space station. These activities are funded in the following budget line items: space station, Russian cooperation, space shuttle, and payload utilization and operations. The science, aeronautics, and technology appropriations provides funding for the research and development activities of NASA. This includes funds to extend our knowledge of the earth, its space environment, and the universe and to invest in new technologies, particularly in aeronautics, to ensure the future competitiveness of the nation. These objectives are achieved through the following elements: space science, life and microgravity sciences and applications, mission to planet earth, aeronautical research and technology, advanced concepts and technology, launch services, mission communication services, and academic programs.

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Budget estimates, fiscal year 1995. Volume 2: Mission support and Inspector General

The mission support appropriations provides funding for NASA's civil service work force, space communication services, safety and quality assurance activities, and for maintenance activities for the NASA institution. These objectives are accomplished through the following elements: safety, reliability, and quality assurance; space communication services; research and program management; and construction of facilities.

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