Performance prediction of optical image stabilizer using SVM for shaker-free production line

NASA Astrophysics Data System (ADS)

Kim, HyungKwan; Lee, JungHyun; Hyun, JinWook; Lim, Haekeun; Kim, GyuYeol; Moon, HyukSoo

2016-04-01

Recent smartphones adapt the camera module with optical image stabilizer(OIS) to enhance imaging quality in handshaking conditions. However, compared to the non-OIS camera module, the cost for implementing the OIS module is still high. One reason is that the production line for the OIS camera module requires a highly precise shaker table in final test process, which increases the unit cost of the production. In this paper, we propose a framework for the OIS quality prediction that is trained with the support vector machine and following module characterizing features : noise spectral density of gyroscope, optically measured linearity and cross-axis movement of hall and actuator. The classifier was tested on an actual production line and resulted in 88% accuracy of recall rate.

Factors affecting economies of scale in combined sewer systems.

PubMed

Maurer, Max; Wolfram, Martin; Anja, Herlyn

2010-01-01

A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.

Estimating the Effects of Module Area on Thin-Film Photovoltaic System Costs: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horowitz, Kelsey A; Fu, Ran; Silverman, Timothy J

We investigate the potential effects of module area on the cost and performance of photovoltaic systems. Applying a bottom-up methodology, we analyzed the costs associated with thin-film modules and systems as a function of module area. We calculate a potential for savings of up to 0.10 dollars/W and 0.13 dollars/W in module manufacturing costs for CdTe and CIGS respectively, with large area modules. We also find that an additional 0.04 dollars/W savings in balance-of-systems costs may be achieved. Sensitivity of the dollar/W cost savings to module efficiency, manufacturing yield, and other parameters is presented. Lifetime energy yield must also bemore » maintained to realize reductions in the levelized cost of energy; the effects of module size on energy yield for monolithic thin-film modules are not yet well understood. Finally, we discuss possible non-cost barriers to adoption of large area modules.« less

All-solution-processed PbS quantum dot solar modules

NASA Astrophysics Data System (ADS)

Jang, Jihoon; Shim, Hyung Cheoul; Ju, Yeonkyeong; Song, Jung Hoon; An, Hyejin; Yu, Jong-Su; Kwak, Sun-Woo; Lee, Taik-Min; Kim, Inyoung; Jeong, Sohee

2015-05-01

A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm2, exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm2 unit cell). Our approach affords trade-offs between power and the active area of the photovoltaic devices, which results in a low-cost power source, and which is scalable to larger areas.A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm2, exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm2 unit cell). Our approach affords trade-offs between power and the active area of the photovoltaic devices, which results in a low-cost power source, and which is scalable to larger areas. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr01508a

Very-low-power and footprint integrated photonic modulators and switches for ICT

NASA Astrophysics Data System (ADS)

Thylén, Lars; Holmström, Petter; Wosinski, Lech

2013-03-01

The current development in photonics for communications and interconnects pose increasing requirements on reduction of footprint, power dissipation and cost, as well as increased bandwidth. Integrated nanophotonics has been viewed as one solution to this, capitalizing on development in nanotechnology as such as well as on increased insights into light matter interaction on the nanoscale. The latter can be exemplified by plasmonics and low-dimensional semiconductors such as quantum dots (QDs). In this scenario the development of better electrooptic materials is also of great importance, the electrooptic polymers being an example, since they potentially offer improved properties for optical phase modulators in terms of power and probably cost and general flexibility. Phase modulators are essential for e.g. the rapidly developing advanced modulation formats for telecom, since phase modulation basically can generate any type of modulation. The electrooptic polymers, e.g. in combination with plasmonics nanoparticle array waveguides or nanostructured hybrid plasmonic media can theoretically give extremely compact and low power dissipation modulators, still to be demonstrated. The low-dimensional semiconductors, e.g. in the shape of QDs, can be employed for modulation or switching functions, offering possibilities in the future for scaling to 2 or 3 dimensions for advanced switching functions. In both the plasmonics and QD cases, nanosizing and low power dissipation are generally due to near-field interactions, albeit being of different physical origin in the two cases. A comparison of all-optical and electronically controlled switching is given.

Online education about herbs and dietary supplements: margin or mission?

PubMed

Kemper, Kathi J; Patel, Sejal

2015-01-01

Online education is increasingly used to train health professionals, but little is known about how variations in cost affect use of elective training. We assessed whether offering registration for free increased the number of modules consumed in both absolute terms (# modules consumed per person, pp) and relative terms (# modules consumed per # modules registered). We analyzed results of the 'natural experiment' on learner's use of the OSU Center for Integrative Health and Wellness online elective curriculum, Introduction Herbs and Dietary Supplements Across the Lifespan, in which costs varied based on monthly discounts for students, faculty, staff, alumni, and members of selected professional associations. Over 7 months there were a total of 905 registrants for 8553 modules. Most (847/905, 94%) registered for free; they completed 1505 (18%) of 8344 modules for which they registered. Fewer (58/905, 6%) people paid for registration; they completed a significantly higher percentage 90/209 (43%, P < 0.001) of modules for which they registered; those who paid full, non-discount rates had the highest completion rates (62%, P < 0.001). Free and paid registrants completed about the same average number of modules per person, pp, (1.8 pp free vs.1.6 pp paid). Although it may not contribute to financial margins, offering free online elective training addresses the institutional mission of increasing the number health professionals trained and the number of modules consumed compared with charging for training. Additional research is needed to determine the impact of pricing on educational outcomes and ultimately on patient care. © The Author(s) 2014.

How Performance-Contingent Reward Prospect Modulates Cognitive Control: Increased Cue Maintenance at the Cost of Decreased Flexibility

ERIC Educational Resources Information Center

Hefer, Carmen; Dreisbach, Gesine

2017-01-01

Growing evidence suggests that reward prospect promotes cognitive stability in terms of increased context or cue maintenance. In 3 Experiments, using different versions of the AX-continuous performance task, we investigated whether this reward effect comes at the cost of decreased cognitive flexibility. Experiment 1 shows that the reward induced…

PVMaT 1998 overview

NASA Astrophysics Data System (ADS)

Mittchell, Richard L.; Symko-Davies, Martha; Thomas, Holly P.; Witt, C. Edwin

1999-03-01

The Photovoltaic Manufacturing Technology (PVMaT) Project is a government/industry research and development (R&D) partnership between the U.S. federal government (through the U.S. Department of Energy [DOE]) and members of the U.S. PV industry. The goals of PVMaT are to assist the U.S. PV industry improve module manufacturing processes and equipment; accelerate manufacturing cost reductions for PV modules, balance-of-systems components, and integrated systems; increase commercial product performance and reliability; and enhance investment opportunities for substantial scale-ups of U.S.-based PV manufacturing plant capacities. The approach for PVMaT has been to cost-share the R&D risk as industry explores new manufacturing options and ideas for improved PV modules and components, advances system and product integration, and develops new system designs. These activities will lead to overall reduced system life-cycle costs for reliable PV end-products. The 1994 PVMaT Product-Driven BOS and Systems activities, as well as Product-Driven Module Manufacturing R&D activities, are just being completed. Fourteen new subcontracts have just been awarded in the areas of PV System and Component Technology and Module Manufacturing Technology. Government funding, subcontractor cost-sharing, and a comparison of the relative efforts by PV technology throughout the PVMaT project are also discussed.

Low-cost evacuated-tube solar collector

NASA Astrophysics Data System (ADS)

1981-02-01

A prototype design for an evacuated tube air cooled solar collector module was completed. A product cost study, based on the production of 60,000 of the prototype modules per year (approx. 1,000,000 square feet annually), estimates that the module as shipped would have a cost at inventory of $7.09 to $7.40 per square foot of aperture. Computer programs were developed to predict the optical and thermal performane of the module. Antireflective coatings (porous aluminum oxide) formed by spraying or dipping were demonstrated but degraded more rapidly when exposed to a high humidity ambient acid etched films. A selective black chromium oxide multi-layered graded film was vapor deposited which had an absorptivity of about 0.9 and an emissivity of 0.03. When the film was heated to temperatures of 4000 C in a gettered vacuum for as little as 24 hours, however, irreversible changes took place both between and within coating layers which resulted in alpha decreasing to about 0.73 and epsilon increasing to 0.14.

Thin EFG octagons

NASA Astrophysics Data System (ADS)

Kalejs, J. P.

1994-06-01

This report describes the impact of the technical achievements made in the first 18 months of the three year PVMaT program at Mobil Solar on lowering the manufacturing costs of its photovoltaic polycrystalline silicon-based modules. Manufacturing cost decreases are being achieved through a reduction of silicon material utilization, increases in productivity and yield in crystal growth, and through improvements in the laser cutting process for EFG wafers. The yield, productivity, and throughput advances made possible by these technical achievements are shown to be able to enhance future market share growth for Mobil Solar products as a consequence of significant reductions in a number of direct manufacturing cost elements in EFG wafer and module production.

The 25 kW power module evolution study. Part 3: Conceptual designs for power module evolutions. Volume 3: Cost estimates

NASA Technical Reports Server (NTRS)

1979-01-01

Cost data generated for the evolutionary power module concepts selected are reported. The initial acquisition costs (design, development, and protoflight unit test costs) were defined and modeled for the baseline 25 kW power module configurations. By building a parametric model of this initial building block, the cost of the 50 kW and the 100 kW power modules were derived by defining only their configuration and programmatic differences from the 25 kW baseline module. Variations in cost for the quantities needed to fulfill the mission scenarios were derived by applying appropriate learning curves.

Cost study of solar cell space power systems

NASA Technical Reports Server (NTRS)

Bernatowicz, D. T.

1972-01-01

Historical costs for solar cell space power systems were evaluated. The study covered thirteen missions that represented a broad cross section of flight projects over the past decade. Fully burdened costs in terms of 1971 dollars are presented for the system and the solar array. The costs correlate reasonably well with array area and do not increase in proportion to array area. The trends for array costs support the contention that solar cell and module standardization reduce costs.

Mobile Equipment Expands Inventory.

ERIC Educational Resources Information Center

McGough, Robert L.; And Others

1978-01-01

Describes the Mobile Equipment Modules (MEM) system in Duluth, Minnesota. MEM is a way to hold down costs and increase learning opportunities by consolidating purchases of expensive shop equipment within the school district, grouping the equipment in modules, and scheduling and moving it from school to school as needed. (MF)

All-solution-processed PbS quantum dot solar modules.

PubMed

Jang, Jihoon; Shim, Hyung Cheoul; Ju, Yeonkyeong; Song, Jung Hoon; An, Hyejin; Yu, Jong-Su; Kwak, Sun-Woo; Lee, Taik-Min; Kim, Inyoung; Jeong, Sohee

2015-05-21

A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm(2), exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm(2) unit cell). Our approach affords trade-offs between power and the active area of the photovoltaic devices, which results in a low-cost power source, and which is scalable to larger areas.

Polyimide based amorphous silicon solar modules

NASA Technical Reports Server (NTRS)

Jeffrey, Frank R.; Grimmer, Derrick P.; Martens, Steven A.; Abudagga, Khaled; Thomas, Michael L.; Noak, Max

1993-01-01

Requirements for space power are increasingly emphasizing lower costs and higher specific powers. This results from new fiscal constraints, higher power requirements for larger applications, and the evolution toward longer distance missions such as a Lunar or Mars base. The polyimide based a-Si modules described are being developed to meet these needs. The modules consist of tandem a-Si solar cell material deposited directly on a roll of polyimide. A laser scribing/printing process subdivides the deposition into discrete cell strips which are series connected to produce the required voltage without cutting the polymer backing. The result is a large, monolithic, blanket type module approximately 30 cm wide and variable in length depending on demand. Current production modules have a specific power slightly over 500 W/Kg with room for significant improvement. Costs for the full blanket modules range from $30/Watt to $150/Watt depending on quantity and engineering requirements. Work to date focused on the modules themselves and adjusting them for the AMO spectrum. Work is needed yet to insure that the modules are suitable for the space environment.

Protons in head-and-neck cancer: bridging the gap of evidence.

PubMed

Ramaekers, Bram L T; Grutters, Janneke P C; Pijls-Johannesma, Madelon; Lambin, Philippe; Joore, Manuela A; Langendijk, Johannes A

2013-04-01

To use Normal Tissue Complication Probability (NTCP) models and comparative planning studies to explore the (cost-)effectiveness of swallowing sparing intensity modulated proton radiotherapy (IMPT) compared with swallowing sparing intensity modulated radiotherapy with photons (IMRT) in head and neck cancer (HNC). A Markov model was constructed to examine and compare the costs and quality-adjusted life years (QALYs) of the following strategies: (1) IMPT for all patients; (2) IMRT for all patients; and (3) IMPT if efficient. The assumption of equal survival for IMPT and IMRT in the base case analysis was relaxed in a sensitivity analysis. Intensity modulated proton radiation therapy and IMRT for all patients yielded 6.620 and 6.520 QALYs and cost €50,989 and €41,038, respectively. Intensity modulated proton radiation therapy if efficient yielded 6.563 QALYs and cost €43,650. The incremental cost-effectiveness ratio of IMPT if efficient versus IMRT for all patients was €60,278 per QALY gained. In the sensitivity analysis, IMRT was more effective (0.967 QALYs) and less expensive (€8218) and thus dominated IMPT for all patients. Cost-effectiveness analysis based on normal tissue complication probability models and planning studies proved feasible and informative and enables the analysis of individualized strategies. The increased effectiveness of IMPT does not seem to outweigh the higher costs for all head-and-neck cancer patients. However, when assuming equal survival among both modalities, there seems to be value in identifying those patients for whom IMPT is cost-effective. Copyright © 2013 Elsevier Inc. All rights reserved.

An Analysis of the Cost and Performance of Photovoltaic Systems as a Function of Module Area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horowitz, Kelsey A.W.; Fu, Ran; Silverman, Tim

We investigate the potential effects of module area on the cost and performance of photovoltaic systems. Applying a bottom-up methodology, we analyzed the costs associated with mc-Si and thin-film modules and systems as a function of module area. We calculate a potential for savings of up to $0.04/W, $0.10/W, and $0.13/W in module manufacturing costs for mc-Si, CdTe, and CIGS respectively, with large area modules. We also find that an additional $0.05/W savings in balance-of-systems costs may be achieved. However, these savings are dependent on the ability to maintain efficiency and manufacturing yield as area scales. Lifetime energy yield mustmore » also be maintained to realize reductions in the levelized cost of energy. We explore the possible effects of module size on efficiency and energy production, and find that more research is required to understand these issues for each technology. Sensitivity of the $/W cost savings to module efficiency and manufacturing yield is presented. We also discuss non-cost barriers to adoption of large area modules.« less

Demonstration of a simplified optical mouse lighting module by integrating the non-Lambertian LED chip and the free-form surface.

PubMed

Pan, Jui-Wen; Tu, Sheng-Han

2012-05-20

A cost-effective, high-throughput, and high-yield method for the efficiency enhancement of an optical mouse lighting module is proposed. We integrated imprinting technology and free-form surface design to obtain a lighting module with high illumination efficiency and uniform intensity distribution. The imprinting technique can increase the light extraction efficiency and modulate the intensity distribution of light-emitting diodes. A modulated light source was utilized to add a compact free-form surface element to create a lighting module with 95% uniformity and 80% optical efficiency.

Structural cost optimization of photovoltaic central power station modules and support structure

NASA Technical Reports Server (NTRS)

Sutton, P. D.; Stolte, W. J.; Marsh, R. O.

1979-01-01

The results of a comprehensive study of photovoltaic module structural support concepts for photovoltaic central power stations and their associated costs are presented. The objective of the study has been the identification of structural cost drivers. Parametric structural design and cost analyses of complete array systems consisting of modules, primary support structures, and foundations were performed. Area related module cost was found to be constant with design, size, and loading. A curved glass module concept was evaluated and found to have the potential to significantly reduce panel structural costs. Conclusions of the study are: array costs do not vary greatly among the designs evaluated; panel and array costs are strongly dependent on design loading; and the best support configuration is load dependent

NREL Adds Solar Array Field to Help Inform Consumers | NREL

Science.gov Websites

PV modules at NREL's new solar array field. Workers install PV modules just north of the NREL parking be Added Each Year Once completed, the new solar array field will house four rows of PV modules. The the lifetime of a PV system, and that increases the per-kilowatt-hour cost of generating solar

Standard Hardware Acquisition and Reliability Program's (SHARP's) efforts in incorporating fiber optic interconnects into standard electronic module (SEM) connectors

NASA Astrophysics Data System (ADS)

Riggs, William R.

1994-05-01

SHARP is a Navy wide logistics technology development effort aimed at reducing the acquisition costs, support costs, and risks of military electronic weapon systems while increasing the performance capability, reliability, maintainability, and readiness of these systems. Lower life cycle costs for electronic hardware are achieved through technology transition, standardization, and reliability enhancement to improve system affordability and availability as well as enhancing fleet modernization. Advanced technology is transferred into the fleet through hardware specifications for weapon system building blocks of standard electronic modules, standard power systems, and standard electronic systems. The product lines are all defined with respect to their size, weight, I/O, environmental performance, and operational performance. This method of defining the standard is very conducive to inserting new technologies into systems using the standard hardware. This is the approach taken thus far in inserting photonic technologies into SHARP hardware. All of the efforts have been related to module packaging; i.e. interconnects, component packaging, and module developments. Fiber optic interconnects are discussed in this paper.

Semiconductor solar cells: Recent progress in terrestrial applications

NASA Astrophysics Data System (ADS)

Avrutin, V.; Izyumskaya, N.; Morkoç, H.

2011-04-01

In the last decade, the photovoltaic industry grew at a rate exceeding 30% per year. Currently, solar-cell modules based on single-crystal and large-grain polycrystalline silicon wafers comprise more than 80% of the market. Bulk Si photovoltaics, which benefit from the highly advanced growth and fabrication processes developed for microelectronics industry, is a mature technology. The light-to-electric power conversion efficiency of the best modules offered on the market is over 20%. While there is still room for improvement, the device performance is approaching the thermodynamic limit of ˜28% for single-junction Si solar cells. The major challenge that the bulk Si solar cells face is, however, the cost reduction. The potential for price reduction of electrical power generated by wafer-based Si modules is limited by the cost of bulk Si wafers, making the electrical power cost substantially higher than that generated by combustion of fossil fuels. One major strategy to bring down the cost of electricity generated by photovoltaic modules is thin-film solar cells, whose production does not require expensive semiconductor substrates and very high temperatures and thus allows decreasing the cost per unit area while retaining a reasonable efficiency. Thin-film solar cells based on amorphous, microcrystalline, and polycrystalline Si as well as cadmium telluride and copper indium diselenide compound semiconductors have already proved their commercial viability and their market share is increasing rapidly. Another avenue to reduce the cost of photovoltaic electricity is to increase the cell efficiency beyond the Shockley-Queisser limit. A variety of concepts proposed along this avenue forms the basis of the so-called third generation photovoltaics technologies. Among these approaches, high-efficiency multi-junction solar cells based on III-V compound semiconductors, which initially found uses in space applications, are now being developed for terrestrial applications. In this article, we discuss the progress, outstanding problems, and environmental issues associated with bulk Si, thin-film, and high-efficiency multi-junction solar cells.

Module 2: Text Versions | State, Local, and Tribal Governments | NREL

Science.gov Websites

benefit of having the shade, especially in the summer, that the overall cost increase was worth it. After how much energy a solar project will produce given your location; the cost of solar technologies and large of a project you'll be able to consider; your utility cost and consumption or what the solar

Development of Manufacturing Technology to Accelerate Cost Reduction of Low Concentration and

DOE Office of Scientific and Technical Information (OSTI.GOV)

Detrick, Adam

The purpose of this project was to accelerate deployment of cost-effective US-based manufacturing of Solaria’s unique c-Si module technology. This effort successfully resulted in the development of US-based manufacturing technology to support two highly-differentiated, market leading product platforms. The project was initially predicated on developing Solaria’s low-concentration PV (LCPV) module technology which at the time of the award was uniquely positioned to exceed the SunShot price goal of $0.50/Wp for standard c-Si modules. The Solaria LCPV module is a 2.5x concentrator that leverages proven, high-reliability PV module materials and low silicon cell usage into a technology package that already hadmore » the lowest direct material cost and leading Levelized Cost of Electricity (LCOE). With over 25 MW commercially deployed globally, the Solaria module was well positioned to continue to lead in PV module cost reduction. Throughout the term of the contract, market conditions changed dramatically and so to did Solaria’s product offerings to support this. However, the manufacturing technology developed for the LCPV module was successfully leveraged and optimized to support two new and different product platforms. BIPV “PowerVision” and High-efficiency “PowerXT” modules. The primary barrier to enabling high-volume PV module manufacturing in the US is the high manual labor component in certain unique aspects of our manufacturing process. The funding was used to develop unique manufacturing automation which makes the manual labor components of these key processes more efficient and increase throughput. At the core of Solaria’s product offerings are its unique and proprietary techniques for dicing and re-arranging solar cells into modules with highly-differentiated characteristics that address key gaps in the c-Si market. It is these techniques that were successfully evolved and deployed into US-based manufacturing site with SunShot funding. Today, Solaria is currently positioned to become the market leader with these two technologies over the coming 24 months largely due to the successful innovations of the underlying manufacturing technology. This success will leverage US-based manufacturing technology and the associated US-jobs to support. Solaria views the project as highly successful and a great example of SunShot funding enabling the creating of US jobs and the deployment of ubiquitous solar energy products.« less

Cost study of solar cell space power systems.

NASA Technical Reports Server (NTRS)

Bernatowicz, D. T.

1972-01-01

A study of historical costs for solar cell space power systems was made by a NASA ad hoc study group. The study covered thirteen missions that represented a broad cross-section of flight projects over the past decade. Fully burdened costs in terms of 1971 dollars are presented for the system and the solar array. The costs correlate reasonably well with array area and do not increase in proportion to array area. The trends for array costs support the contention that solar cell and module standardization would reduce costs.

Complementary modulation of N2 and CRN by conflict frequency.

PubMed

Grützmann, Rosa; Riesel, Anja; Klawohn, Julia; Kathmann, Norbert; Endrass, Tanja

2014-08-01

The present study investigated the modulation of the N2 and the correct-related negativity (CRN) by conflict frequency. Conflict costs, as measured by reaction times and error rate, were reduced with increasing conflict frequency, indicating improved conflict resolution. N2 amplitudes in incompatible trials increased with higher conflict frequency, while postresponse CRN amplitudes decreased. In concert with behavioral findings of reduced conflict costs and greater interference suppression, the increase of N2 might reflect enhanced conflict resolution during stimulus processing. The CRN, however, might reflect postresponse implementation of cognitive control, which is reduced when conflict is already adequately resolved during stimulus processing. Furthermore, N2 and CRN in incompatible trials were inversely related on the between- and within-subject level, implying that the two modes of implementing cognitive control are applied complementarily. Copyright © 2014 Society for Psychophysiological Research.

High-throughput manufacturing of thin-film CdS/CdTe photovoltaic modules. Annual subcontract report, 16 November 1994--15 November 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandwisch, D.W.

1997-02-01

The objectives of this subcontract are to advance Solar Cells, Inc.`s (SCI`s) photovoltaic manufacturing technologies, reduce module production costs, increase module performance, and provide the groundwork for SCI to expand its commercial production capacities. Activities during the second year of the program concentrated on process development, equipment design and testing, quality assurance, and ES and H programs. These efforts broadly addressed the issues of the manufacturing process for producing thin-film monolithic CdS/CdTe photovoltaic modules.

Transportation. Teacher's Guide and Student Guide. Net Energy Unit. Draft.

ERIC Educational Resources Information Center

Treagust, David F.

This module is intended to increase the students' comprehension of costs, in terms of money and in energy, involved in various modes of transportation. Four main inquiries are covered in the module: (1) money saved by car pooling to school; (2) reductions in fuel consumption possible without car pooling; (3) comparisons of inter-city and urban…

Land Application of Wastes: An Educational Program. Costing Land Application Systems - Module 10.

ERIC Educational Resources Information Center

Clarkson, W. W.; And Others

This module expands on the concepts of cost estimation and comparison of costs among various treatment alternatives which were presented in a previous module. The need for useful published cost data is stressed. Criteria for selecting cost references are presented, and examples of charts and graphs from several of these are used in comparing land…

Management of radioactive waste gases from PET radiopharmaceutical synthesis using cost effective capture systems integrated with a cyclotron safety system.

PubMed

Stimson, D H R; Pringle, A J; Maillet, D; King, A R; Nevin, S T; Venkatachalam, T K; Reutens, D C; Bhalla, R

2016-09-01

The emphasis on the reduction of gaseous radioactive effluent associated with PET radiochemistry laboratories has increased. Various radioactive gas capture strategies have been employed historically including expensive automated compression systems. We have implemented a new cost-effective strategy employing gas capture bags with electronic feedback that are integrated with the cyclotron safety system. Our strategy is suitable for multiple automated 18 F radiosynthesis modules and individual automated 11 C radiosynthesis modules. We describe novel gas capture systems that minimize the risk of human error and are routinely used in our facility.

Photovoltaic design optimization for terrestrial applications

NASA Technical Reports Server (NTRS)

Ross, R. G., Jr.

1978-01-01

As part of the Jet Propulsion Laboratory's Low-Cost Solar Array Project, a comprehensive program of module cost-optimization has been carried out. The objective of these studies has been to define means of reducing the cost and improving the utility and reliability of photovoltaic modules for the broad spectrum of terrestrial applications. This paper describes one of the methods being used for module optimization, including the derivation of specific equations which allow the optimization of various module design features. The method is based on minimizing the life-cycle cost of energy for the complete system. Comparison of the life-cycle energy cost with the marginal cost of energy each year allows the logical plant lifetime to be determined. The equations derived allow the explicit inclusion of design parameters such as tracking, site variability, and module degradation with time. An example problem involving the selection of an optimum module glass substrate is presented.

Online virtual cases to teach resource stewardship.

PubMed

Zhou, Linghong Linda; Tait, Gordon; Sandhu, Sharron; Steiman, Amanda; Lake, Shirley

2018-06-11

As health care costs rise, medical education must focus on high-value clinical decision making. To teach and assess efficient resource use in rheumatology, online virtual interactive cases (VICs) were developed to simulate real patient encounters to increase price transparency and reinforce cost consciousness. To teach and assess efficient resource use in rheumatology, online virtual interactive cases (VICs) were developed METHODS: The VIC modules were distributed to a sample of medical students and internal medicine residents, who were required to assess patients, order appropriate investigations, develop differential diagnoses and formulate management plans. Each action was associated with a time and price, with the totals compared against ideals. Trainees were evaluated not only on their diagnosis and patient management, but also on the total time, cost and value of their selected workup. Trainee responses were tracked anonymously, with opportunity to provide feedback at the end of each case. Seventeen medical trainees completed a total of 48 VIC modules. On average, trainees spent CAN $227.52 and 68 virtual minutes on each case, which was lower than expected. This may have been the result of a low management score of 52.4%, although on average 92.0% of participants in each case achieved the correct diagnosis. In addition, 85.7% felt more comfortable working up similar cases, and 57.1% believed that the modules increased their ability to appropriately order cost-conscious rheumatology investigations. Our initial assessment of the VIC rheumatology modules was positive, supporting their role as an effective tool in teaching an approach to rheumatology patients, with an emphasis on resource stewardship. Future directions include the expansion of cases, based on feedback, wider dissemination and an evaluation of learning retention. © 2018 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Cost and logistics of implementing a tissue-based American College of Surgeons/Association of Program Directors in Surgery surgical skills curriculum for general surgery residents of all clinical years.

PubMed

Henry, Brandon; Clark, Philip; Sudan, Ranjan

2014-02-01

The cost and logistics of deploying the American College of Surgeons (ACS)/Association of Program Directors in Surgery (APDS) National Technical Skills Curriculum across all training years are not known. This information is essential for residency programs choosing to adopt similar curricula. A task force evaluated the authors' institution's existing simulation curriculum and enhanced it by implementing the ACS/APDS modules. A 35-module curriculum was administered to 35 general surgery residents across all 5 clinical years. The costs and logistics were noted, and resident satisfaction was assessed. The annual operational cost was $110,300 ($3,150 per resident). Cost per module, per resident was $940 for the cadaveric module compared with $220 and $240 for dry simulation and animal tissue-based modules, respectively. Resident satisfaction improved from 2.45 to 4.78 on a 5-point, Likert-type scale after implementing the ACS/APDS modules. The ACS/APDS skills curriculum was implemented successfully across all clinical years. Cadaveric modules were the most expensive. Animal and dry simulation modules were equivalent in cost. The addition of tissue-based modules was associated with high satisfaction. Copyright © 2014 Elsevier Inc. All rights reserved.

Cost of New Technologies in Prostate Cancer Treatment: Systematic Review of Costs and Cost Effectiveness of Robotic-assisted Laparoscopic Prostatectomy, Intensity-modulated Radiotherapy, and Proton Beam Therapy.

PubMed

Schroeck, Florian Rudolf; Jacobs, Bruce L; Bhayani, Sam B; Nguyen, Paul L; Penson, David; Hu, Jim

2017-11-01

Some of the high costs of robot-assisted radical prostatectomy (RARP), intensity-modulated radiotherapy (IMRT), and proton beam therapy may be offset by better outcomes or less resource use during the treatment episode. To systematically review the literature to identify the key economic trade-offs implicit in a particular treatment choice for prostate cancer. We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement and protocol. We searched Medline, Embase, and Web of Science for articles published between January 2001 and July 2016, which compared the treatment costs of RARP, IMRT, or proton beam therapy to the standard treatment. We identified 37, nine, and three studies, respectively. RARP is costlier than radical retropubic prostatectomy for hospitals and payers. However, RARP has the potential for a moderate cost advantage for payers and society over a longer time horizon when optimal cancer and quality-of-life outcomes are achieved. IMRT is more expensive from a payer's perspective compared with three-dimensional conformal radiotherapy, but also more cost effective when defined by an incremental cost effectiveness ratio <$50 000 per quality-adjusted life year. Proton beam therapy is costlier than IMRT and its cost effectiveness remains unclear given the limited comparative data on outcomes. Using the Grades of Recommendation, Assessment, Development and Evaluation approach, the quality of evidence was low for RARP and IMRT, and very low for proton beam therapy. Treatment with new versus traditional technologies is costlier. However, given the low quality of evidence and the inconsistencies across studies, the precise difference in costs remains unclear. Attempts to estimate whether this increased cost is worth the expense are hampered by the uncertainty surrounding improvements in outcomes, such as cancer control and side effects of treatment. If the new technologies can consistently achieve better outcomes, then they may be cost effective. We review the cost and cost effectiveness of robot-assisted radical prostatectomy, intensity-modulated radiotherapy, and proton beam therapy in prostate cancer treatment. These technologies are costlier than their traditional counterparts. It remains unclear whether their use is associated with improved cure and reduced morbidity, and whether the increased cost is worth the expense. Published by Elsevier B.V.

The application of the Luus-Jaakola direct search method to the optimization of a hybrid renewable energy system

NASA Astrophysics Data System (ADS)

Jatzeck, Bernhard Michael

2000-10-01

The application of the Luus-Jaakola direct search method to the optimization of stand-alone hybrid energy systems consisting of wind turbine generators (WTG's), photovoltaic (PV) modules, batteries, and an auxiliary generator was examined. The loads for these systems were for agricultural applications, with the optimization conducted on the basis of minimum capital, operating, and maintenance costs. Five systems were considered: two near Edmonton, Alberta, and one each near Lethbridge, Alberta, Victoria, British Columbia, and Delta, British Columbia. The optimization algorithm used hourly data for the load demand, WTG output power/area, and PV module output power. These hourly data were in two sets: seasonal (summer and winter values separated) and total (summer and winter values combined). The costs for the WTG's, PV modules, batteries, and auxiliary generator fuel were full market values. To examine the effects of price discounts or tax incentives, these values were lowered to 25% of the full costs for the energy sources and two-thirds of the full cost for agricultural fuel. Annual costs for a renewable energy system depended upon the load, location, component costs, and which data set (seasonal or total) was used. For one Edmonton load, the cost for a renewable energy system consisting of 27.01 m2 of WTG area, 14 PV modules, and 18 batteries (full price, total data set) was 6873/year. For Lethbridge, a system with 22.85 m2 of WTG area, 47 PV modules, and 5 batteries (reduced prices, seasonal data set) cost 2913/year. The performance of renewable energy systems based on the obtained results was tested in a simulation using load and weather data for selected days. Test results for one Edmonton load showed that the simulations for most of the systems examined ran for at least 17 hours per day before failing due to either an excessive load on the auxiliary generator or a battery constraint being violated. Additional testing indicated that increasing the generator capacity and reducing the maximum allowed battery charge current during the time of the day at which these failures occurred allowed the simulation to successfully operate.

Modular solar food dryers for farm use

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, C.J. Jr.; Coleman, R.L.; Berry, R.E.

1981-01-01

Several solar food dryer modules have been constructed. Their design has been based on a low-cost, small-scale solar dryer using a unique parabolic reflector construction to increase radiation on the drying surface. Each module has a drying surface of 1.1 M/sup 2/ and a parabolic reflector area of 3.3 M/sup 2/. Some modules are being used to dry mango slices (a potential new food product) for market testing, while others are used for experiments to improve drying efficiency. A description is given of the operating conditions of the modules drying mango slices and the most effective modifications.

Supply Constraints Analysis | Energy Analysis | NREL

Science.gov Websites

module cost, and future price could be critical to the economic viability of this PV technology. Even constraints on future CdTe PV module deployment and found that: CdTe PV modules can remain cost-competitive and 4070 GW of annual CdTe production by 2030. Cost estimates were based on NREL's manufacturing cost

User Delay Cost Model and Facilities Maintenance Cost Model for a Terminal Control Area : Volume 2. User's Manual and Program Documentation for the User Delay Cost Model

DOT National Transportation Integrated Search

1978-05-01

The User Delay Cost Model (UDCM) is a Monte Carlo simulation of certain classes of movement of air traffic in the Boston Terminal Control Area (TCA). It incorporates a weather module, an aircraft generation module, a facilities module, and an air con...

Improvements in Cz silicon PV module manufacturing

NASA Astrophysics Data System (ADS)

King, Richard R.; Mitchell, Kim W.; Jester, Theresa L.

1997-02-01

Work focused on reducing the cost per watt of Cz Si photovoltaic modules under Phase I of Siemens Solar Industries' DOE/NREL PVMaT 4A subcontract is described. Module cost components are analyzed and solutions to high-cost items are discussed in terms of specific module designs. The approaches of using larger cells and modules to reduce per-part processing cost, and of minimizing yield loss are particularly leveraging. Yield components for various parts of the fabrication process and various types of defects are shown, and measurements of the force required to break wafers throughout the cell fabrication sequence are given. The most significant type of yield loss is mechanical breakage. The implementation of statistical process control on key manufacturing processes at Siemens Solar Industries is described. Module configurations prototyped during Phase I of this project and scheduled to begin production in Phase II have a projected cost per watt reduction of 19%.

Low-cost optical interconnect module for parallel optical data links

NASA Astrophysics Data System (ADS)

Noddings, Chad; Hirsch, Tom J.; Olla, M.; Spooner, C.; Yu, Jason J.

1995-04-01

We have designed, fabricated, and tested a prototype parallel ten-channel unidirectional optical data link. When scaled to production, we project that this technology will satisfy the following market penetration requirements: (1) up to 70 meters transmission distance, (2) at least 1 gigabyte/second data rate, and (3) 0.35 to 0.50 MByte/second volume selling price. These goals can be achieved by means of the assembly innovations described in this paper: a novel alignment method that is integrated with low-cost, few chip module packaging techniques, yielding high coupling and reducing the component count. Furthermore, high coupling efficiency increases projected reliability reducing the driver's power requirements.

Monolithically interconnected silicon-film™ module technology

NASA Astrophysics Data System (ADS)

DelleDonne, E. J.; Ford, D. H.; Hall, R. B.; Ingram, A. E.; Rand, J. A.; Barnett, A. M.

1999-03-01

AstroPower is developing an advanced thin-silicon-based, photovoltaic module product. A low-cost monolithic interconnected device is being integrated into a module that combines the design and process features of advanced light trapped, thin-silicon solar cells. This advanced product incorporates a low-cost substrate, a nominally 50-μm thick grown silicon layer with minority carrier diffusion lengths exceeding the active layer thickness, light trapping due to back-surface reflection, and back-surface passivation. The thin silicon layer enables high solar cell performance and can lead to a module conversion efficiency as high as 19%. These performance design features, combined with low-cost manufacturing using relatively low-cost capital equipment, continuous processing and a low-cost substrate, will lead to high-performance, low-cost photovoltaic panels.

Improvement of modulation bandwidth in electroabsorption-modulated laser by utilizing the resonance property in bonding wire.

PubMed

Kwon, Oh Kee; Han, Young Tak; Baek, Yong Soon; Chung, Yun C

2012-05-21

We present and demonstrate a simple and cost-effective technique for improving the modulation bandwidth of electroabsorption-modulated laser (EML). This technique utilizes the RF resonance caused by the EML chip (i.e., junction capacitance) and bonding wire (i.e, wire inductance). We analyze the effects of the lengths of the bonding wires on the frequency responses of EML by using an equivalent circuit model. To verify this analysis, we package a lumped EML chip on the sub-mount and measure its frequency responses. The results show that, by using the proposed technique, we can increase the modulation bandwidth of EML from ~16 GHz to ~28 GHz.

The cost of radiotherapy in a decade of technology evolution.

PubMed

Van de Werf, Evelyn; Verstraete, Jan; Lievens, Yolande

2012-01-01

To quantify changes in radiotherapy costs occurring in a decade of medical-technological evolution. The activity-based costing (ABC) model of the University Hospitals Leuven (UHL) radiotherapy (RT) department was adapted to current RT standards. It allocated actual resource costs to the treatments based on the departmental work-flow and patient mix in 2009. A benchmark with the former model analyzed the cost increases related to changes in RT infrastructure and practice over 10 years. A considerable increase in total RT costs was observed, resulting from higher capital investments (96%) and personnel cost (103%), the latter dominating the total picture. Treatment delivery remains the most costly activity, boosted by the cost of improved quality assurance (QA), 23% of total product costs, coming along with more advanced RT techniques. Hence, cost increases at the product level are most obvious for complex treatments, such as intensity-modulated radiotherapy (IMRT), representing cost increases ranging between 38% and 88% compared to conformal approaches. The ABC model provides insight into the financial consequences of evolving technology and practice. Such data are a mandatory first step in our strive to prove RT cost-effectiveness and thus support optimal reimbursement and provision of radiotherapy departments. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Printed interconnects for photovoltaic modules

DOE PAGES

Fields, J. D.; Pach, G.; Horowitz, K. A. W.; ...

2016-10-21

Film-based photovoltaic modules employ monolithic interconnects to minimize resistance loss and enhance module voltage via series connection. Conventional interconnect construction occurs sequentially, with a scribing step following deposition of the bottom electrode, a second scribe after deposition of absorber and intermediate layers, and a third following deposition of the top electrode. This method produces interconnect widths of about 300 µm, and the area comprised by interconnects within a module (generally about 3%) does not contribute to power generation. The present work reports on an increasingly popular strategy capable of reducing the interconnect width to less than 100 µm: printing interconnects.more » Cost modeling projects a savings of about $0.02/watt for CdTe module production through the use of printed interconnects, with savings coming from both reduced capital expense and increased module power output. Printed interconnect demonstrations with copper-indium-gallium-diselenide and cadmium-telluride solar cells show successful voltage addition and miniaturization down to 250 µm. As a result, material selection guidelines and considerations for commercialization are discussed.« less

High throughput manufacturing of thin-film CdTe photovoltaic modules. Annual subcontract report, 16 November 1993--15 November 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandwisch, D W

1995-11-01

This report describes work performed by Solar Cells, Inc. (SCI), under a 3-year subcontract to advance SCI`s PV manufacturing technologies, reduce module production costs, increase module performance, and provide the groundwork for SCI to expand its commercial production capacities. SCI will meet these objectives in three phases by designing, debugging, and operating a 20-MW/year, automated, continuous PV manufacturing line that produces 60-cm {times} 120-cm thin-film CdTe PV modules. This report describes tasks completed under Phase 1 of the US Department of Energy`s PV Manufacturing Technology program.

Reactive granular optics for passive tracking of the sun

NASA Astrophysics Data System (ADS)

Frenkel, I.; Niv, A.

2017-08-01

The growing need for cost-effective renewable energy sources is hampered by the stagnation in solar cell technology, thus preventing a substantial reduction in the module and energy-production price. Lowering the energy-production cost could be achieved by using modules with efficiency. One of the possible means for increasing the module efficiency is concentrated photovoltaics (CPV). CPV, however, requires complex and accurate active tracking of the sun that reduces much of its cost-effectiveness. Here, we propose a passive tracking scheme based on a reactive optical device. The optical reaction is achieved by a new kind of light activated mechanical force that acts on micron-sized particles. This optical force allows the formation of granular disordered optical media that can be switched from being opaque to become transparent based on the intensity of light it interacts with. Such media gives rise to an efficient passive tracking scheme that when combined with an external optical cavity forms a new solar power conversion approach. Being external to the cell itself, this approach is indifferent to the type of semiconducting material that is used, as well as to other aspects of the cell design. This, in turn, liberates the cell layout from its optical constraints thus paving the way to higher efficiencies at lower module price.

III-Vs at Scale: A PV Manufacturing Cost Analysis of the Thin Film Vapor-Liquid-Solid Growth Mode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Maxwell; Horowitz, Kelsey; Woodhouse, Michael

The authors present a manufacturing cost analysis for producing thin-film indium phosphide modules by combining a novel thin-film vapor-liquid-solid (TF-VLS) growth process with a standard monolithic module platform. The example cell structure is ITO/n-TiO2/p-InP/Mo. For a benchmark scenario of 12% efficient modules, the module cost is estimated to be $0.66/W(DC) and the module cost is calculated to be around $0.36/W(DC) at a long-term potential efficiency of 24%. The manufacturing cost for the TF-VLS growth portion is estimated to be ~$23/m2, a significant reduction compared with traditional metalorganic chemical vapor deposition. The analysis here suggests the TF-VLS growth mode could enablemore » lower-cost, high-efficiency III-V photovoltaics compared with manufacturing methods used today and open up possibilities for other optoelectronic applications as well.« less

Cost of Sawing Timber (COST) Module (Version 1.0) for Windows®

Treesearch

A. Jefferson, Jr. Palmer; Janice K. Wiedenbeck; Robert W. Mayer; Robert W. Mayer

2005-01-01

The Cost of Sawing Timber (COST) Module calculates the cost of operations per minute and per thousand board feet for a hardwood sawmill. It may be used independently or as a source of cost information for use in sawmill efficiency software such as the SOLVE program. Cost figures are calculated on the basis of information entered by the user. Sawmill managers use these...

Waste Management Facilities Cost Information report for Greater-Than-Class C and DOE equivalent special case waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feizollahi, F.; Shropshire, D.

This Waste Management Facility Cost Information (WMFCI) report for Greater-Than-Class C low-level waste (GTCC LLW) and DOE equivalent special case waste contains preconceptual designs and planning level life-cycle cost (PLCC) estimates for treatment, storage, and disposal facilities needed for management of GTCC LLW and DOE equivalent waste. The report contains information on 16 facilities (referred to as cost modules). These facilities are treatment facility front-end and back-end support functions (administration support, and receiving, preparation, and shipping cost modules); seven treatment concepts (incineration, metal melting, shredding/compaction, solidification, vitrification, metal sizing and decontamination, and wet/air oxidation cost modules); two storage concepts (enclosedmore » vault and silo); disposal facility front-end functions (disposal receiving and inspection cost module); and four disposal concepts (shallow-land, engineered shallow-land, intermediate depth, and deep geological cost modules). Data in this report allow the user to develop PLCC estimates for various waste management options. A procedure to guide the U.S. Department of Energy (DOE) and its contractor personnel in the use of estimating data is also included in this report.« less

Reconfigurable WDM-PON empowered by a low-cost 8-channel directly modulated laser module

NASA Astrophysics Data System (ADS)

Zhang, Yi-ming; Liu, Yu; Zhang, Zhi-ke; Zhao, Ze-ping; Tian, Ye; Zhu, Ning-hua

2017-11-01

A 10 Gbit/s 16-km-long reconfigurable wavelength-division-multiplexing passive optical network (WDM-PON) is presented empowered by a low-cost multi-channel directly modulated laser (DML) module. Compared with the case using discrete devices in conventional scheme, the proposed DML module provides a cost-effective solution with reduced complexity. The clear eye diagram and the bit error rate ( BER) of less than 2×10-7 with a sensitivity of -7 dBm are obtained. Due to the special packaging design, the crosstalk between channels under condition of simultaneous operation can be negligible.

Perceived Cost and Intrinsic Motor Variability Modulate the Speed-Accuracy Trade-Off

PubMed Central

Bertucco, Matteo; Bhanpuri, Nasir H.; Sanger, Terence D.

2015-01-01

Fitts’ Law describes the speed-accuracy trade-off of human movements, and it is an elegant strategy that compensates for random and uncontrollable noise in the motor system. The control strategy during targeted movements may also take into account the rewards or costs of any outcomes that may occur. The aim of this study was to test the hypothesis that movement time in Fitts’ Law emerges not only from the accuracy constraints of the task, but also depends on the perceived cost of error for missing the targets. Subjects were asked to touch targets on an iPad® screen with different costs for missed targets. We manipulated the probability of error by comparing children with dystonia (who are characterized by increased intrinsic motor variability) to typically developing children. The results show a strong effect of the cost of error on the Fitts’ Law relationship characterized by an increase in movement time as cost increased. In addition, we observed a greater sensitivity to increased cost for children with dystonia, and this behavior appears to minimize the average cost. The findings support a proposed mathematical model that explains how movement time in a Fitts-like task is related to perceived risk. PMID:26447874

An automation of design and modelling tasks in NX Siemens environment with original software - cost module

NASA Astrophysics Data System (ADS)

Zbiciak, R.; Grabowik, C.; Janik, W.

2015-11-01

The design-constructional process is a creation activity which strives to fulfil, as well as it possible at the certain moment of time, all demands and needs formulated by a user taking into account social, technical and technological advances. Engineer knowledge and skills and their inborn abilities have the greatest influence on the final product quality and cost. They have also deciding influence on product technical and economic value. Taking into account above it seems to be advisable to make software tools that support an engineer in the process of manufacturing cost estimation. The Cost module is built with analytical procedures which are used for relative manufacturing cost estimation. As in the case of the Generator module the Cost module was written in object programming language C# in Visual Studio environment. During the research the following eight factors, that have the greatest influence on overall manufacturing cost, were distinguished and defined: (i) a gear wheel teeth type it is straight or helicoidal, (ii) a gear wheel design shape A, B with or without wheel hub, (iii) a gear tooth module, (iv) teeth number, (v) gear rim width, (vi) gear wheel material, (vii) heat treatment or thermochemical treatment, (viii) accuracy class. Knowledge of parameters (i) to (v) is indispensable for proper modelling of 3D gear wheels models in CAD system environment. These parameters are also processed in the Cost module. The last three parameters it is (vi) to (viii) are exclusively used in the Cost module. The estimation of manufacturing relative cost is based on indexes calculated for each particular parameter. Estimated in this way the manufacturing relative cost gives an overview of design parameters influence on the final gear wheel manufacturing cost. This relative manufacturing cost takes values from 0.00 to 1,00 range. The bigger index value the higher relative manufacturing cost is. Verification whether the proposed algorithm of relative manufacturing costs estimation has been designed properly was made by comparison of the achieved from the algorithm results with those obtained from industry. This verification has indicated that in most cases both group of results are similar. Taking into account above it is possible to draw a conclusion that the Cost module might play significant role in design constructional process by adding an engineer at the selection stage of alternative gear wheels design. It should be remembered that real manufacturing cost can differ significantly according to available in a factory manufacturing techniques and stock of machine tools.

Performance of a Low-Cost, Low-Concentration Photovoltaic Module

NASA Astrophysics Data System (ADS)

Shell, Kara A.; Brown, Scott A.; Schuetz, Mark A.; Davis, Bob J.; French, Roger H.

2011-12-01

In order to significantly reduce the cost of solar power, Replex Plastics has developed a low-cost, low-concentration PV module incorporating acrylic mirror reflectors. The reflectors are compound parabolic concentrators designed for use with low-accuracy single axis trackers. The prototypes use crystalline silicon photovoltaic cells and achieved 7.1x concentration over a receiver without reflectors. The 1×1.6 m module used 1/10th the silicon of a standard module and produced a max power of 140 W.

Nuclear Power Plant Module, NPP-1: Nuclear Power Cost Analysis.

ERIC Educational Resources Information Center

Whitelaw, Robert L.

The purpose of the Nuclear Power Plant Modules, NPP-1, is to determine the total cost of electricity from a nuclear power plant in terms of all the components contributing to cost. The plan of analysis is in five parts: (1) general formulation of the cost equation; (2) capital cost and fixed charges thereon; (3) operational cost for labor,…

All-optical phase modulation for integrated interferometric biosensors.

PubMed

Dante, Stefania; Duval, Daphné; Sepúlveda, Borja; González-Guerrero, Ana Belen; Sendra, José Ramón; Lechuga, Laura M

2012-03-26

We present the theoretical and the experimental implementation of an all-optical phase modulation system in integrated Mach-Zehnder Interferometers to solve the drawbacks related to the periodic nature of the interferometric signal. Sensor phase is tuned by modulating the emission wavelength of low-cost commercial laser diodes by changing their output power. FFT deconvolution of the signal allows for direct phase readout, immune to sensitivity variations and to light intensity fluctuations. This simple phase modulation scheme increases the signal-to-noise ratio of the measurements in one order of magnitude, rendering in a sensor with a detection limit of 1.9·10⁻⁷ RIU. The viability of the all-optical modulation approach is demonstrated with an immunoassay detection as a biosensing proof of concept.

Development of Low Cost, High Energy-Per-Unit-Area Solar Cell Modules

NASA Technical Reports Server (NTRS)

Jones, G. T.; Chitre, S.

1977-01-01

Work on the development of low cost, high energy per unit area solar cell modules was conducted. Hexagonal solar cell and module efficiencies, module packing ratio, and solar cell design calculations were made. The cell grid structure and interconnection pattern was designed and the module substrates were fabricated for the three modules to be used. It was demonstrated that surface macrostructures significantly improve cell power output and photovoltaic energy conversion efficiency.

Cost-effective bidirectional digitized radio-over-fiber systems employing sigma delta modulation

NASA Astrophysics Data System (ADS)

Lee, Kyung Woon; Jung, HyunDo; Park, Jung Ho

2016-11-01

We propose a cost effective digitized radio-over-fiber (D-RoF) system employing a sigma delta modulation (SDM) and a bidirectional transmission technique using phase modulated downlink and intensity modulated uplink. SDM is transparent to different radio access technologies and modulation formats, and more suitable for a downlink of wireless system because a digital to analog converter (DAC) can be avoided at the base station (BS). Also, Central station and BS share the same light source by using a phase modulation for the downlink and an intensity modulation for the uplink transmission. Avoiding DACs and light sources have advantages in terms of cost reduction, power consumption, and compatibility with conventional wireless network structure. We have designed a cost effective bidirectional D-RoF system using a low pass SDM and measured the downlink and uplink transmission performance in terms of error vector magnitude, signal spectra, and constellations, which are based on the 10MHz LTE 64-QAM standard.

Ion propulsion cost effectivity

NASA Technical Reports Server (NTRS)

Zafran, S.; Biess, J. J.

1978-01-01

Ion propulsion modules employing 8-cm thrusters and 30-cm thrusters were studied for Multimission Modular Spacecraft (MMS) applications. Recurring and nonrecurring cost elements were generated for these modules. As a result, ion propulsion cost drivers were identified to be Shuttle charges, solar array, power processing, and thruster costs. Cost effective design approaches included short length module configurations, array power sharing, operation at reduced thruster input power, simplified power processing units, and power processor output switching. The MMS mission model employed indicated that nonrecurring costs have to be shared with other programs unless the mission model grows. Extended performance missions exhibited the greatest benefits when compared with monopropellant hydrazine propulsion.

Process-Based Cost Modeling of Photonics Manufacture: The Cost Competitiveness of Monolithic Integration of a 1550-nm DFB Laser and an Electroabsorptive Modulator on an InP Platform

NASA Astrophysics Data System (ADS)

Fuchs, Erica R. H.; Bruce, E. J.; Ram, R. J.; Kirchain, Randolph E.

2006-08-01

The monolithic integration of components holds promise to increase network functionality and reduce packaging expense. Integration also drives down yield due to manufacturing complexity and the compounding of failures across devices. Consensus is lacking on the economically preferred extent of integration. Previous studies on the cost feasibility of integration have used high-level estimation methods. This study instead focuses on accurate-to-industry detail, basing a process-based cost model of device manufacture on data collected from 20 firms across the optoelectronics supply chain. The model presented allows for the definition of process organization, including testing, as well as processing conditions, operational characteristics, and level of automation at each step. This study focuses on the cost implications of integration of a 1550-nm DFB laser with an electroabsorptive modulator on an InP platform. Results show the monolithically integrated design to be more cost competitive over discrete component options regardless of production scale. Dominant cost drivers are packaging, testing, and assembly. Leveraging the technical detail underlying model projections, component alignment, bonding, and metal-organic chemical vapor deposition (MOCVD) are identified as processes where technical improvements are most critical to lowering costs. Such results should encourage exploration of the cost advantages of further integration and focus cost-driven technology development.

Binary processing and display concepts for low-cost Omega receivers. [airborne systems simulation

NASA Technical Reports Server (NTRS)

Lilley, R. W.

1974-01-01

A description is given of concepts related to plans for developing a low-cost, all-digital Omega receiver capable of offering to the small-aircraft pilot a reliable and accurate navigation aid. The receiver base considered includes a receiver front-end module, a receiver control module, a memory-aided phase-locked loop module, a housekeeping timer module, and a synthesizer module.

Advanced Fuel Cycle Cost Basis – 2017 Edition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dixon, B. W.; Ganda, F.; Williams, K. A.

This report, commissioned by the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the DOE Nuclear Technology Research and Development (NTRD) Program (previously the Fuel Cycle Research and Development (FCRD) and the Advanced Fuel Cycle Initiative (AFCI)). The report describes the NTRD cost basis development process, reference information on NTRD cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This reportmore » contains reference cost data for numerous fuel cycle cost modules (modules A-O) as well as cost modules for a number of reactor types (R modules). The fuel cycle cost modules were developed in the areas of natural uranium mining and milling, thorium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, managed decay storage, recycled product storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste. Since its inception, this report has been periodically updated. The last such internal document was published in August 2015 while the last external edition was published in December of 2009 as INL/EXT-07-12107 and is available on the Web at URL: www.inl.gov/technicalpublications/Documents/4536700.pdf. This current report (Sept 2017) is planned to be reviewed for external release, at which time it will replace the 2009 report as an external publication. This information is used in the ongoing evaluation of nuclear fuel cycles by the NE NTRD program.« less

Optimisation robuste des aeronefs et des groupes turboreacteurs

NASA Astrophysics Data System (ADS)

Couturier, Philippe

Future aircraft and powerplant designs will need to meet and perhaps anticipate increasingly demanding operational constraints. This progressive evolution in design requirements is already at work and arises from the combined impacts of increasingly stringent environmental norms with regards to noise and atmospheric emissions, a depletion of fossil fuel reserves which is expected to drive fuel costs upwards, as well as a steady increase in air traffic. In order to adapt to these market shifts, aircraft and powerplant companies will need to explore the potential range of benefits and risks associated with a wide spectrum of new designs and technologies. At the same time, it will be necessary to ensure that the resulting end products provide cost effective solutions when operated in the economic environment foreseen for the next generation of aircrafts. The objective of this study is to develop a methodology which enables the selection of optimal robust designs at the preliminary design stage as well as to quantify the compromise between a robust design and a potential gain in performance. The developed methodology is used in the design of a seventy passenger aircraft in order to determine the effects of uncertainty. The methodology seeks to optimize the design while attenuating its sensitivity to uncertainties. The goal is to reduce the likelihood of costly concept reformulations in the later stages of the product development process. A design platform was developed to enable the study at a conceptual level of aircraft and engine performance. It comprises four modules namely: the aircraft design and performance software Pacelab APD, a metamodel constructed with the software GasTurb to calculate engine performance, a module to predict the noise level, and a module to determine the operating costs. The last two modules were constructed using data from the literature. The effects related to two types of uncertainties present at the preliminary design stage were analyzed. These are uncertainties related to the market forecast for when the next generation of aircrafts will be in service as well as uncertainties of the level of fidelity of the models used. Based on predictions for future oil costs, the research found that an aircraft built for a similar cruising speed as today's jet aircrafts will minimize the mean of the predicted operating cost by having a configuration that minimizes fuel consumption. Conversely, it has been determined that fuel cost does not affect the design optimized to minimize the mean of the predicted operating costs when the cruise Mach number is variable. Furthermore, the use of Pareto fronts in order to quantify the compromise between a robust design and a potential gain in performance showed that the design variables have little influence on the sensitivity of the operating cost subject to model uncertainties. It has also been determined that neglecting uncertainties during the design process can lead to the selection of a configuration with a high risk of not satisfying the constraints.

Applications of ethylene vinyl acetate as an encapsulation material for terrestrial photovoltaic modules

NASA Technical Reports Server (NTRS)

Cuddihy, E. F.; Coulbert, C. D.; Liang, R. H.; Gupta, A.; Willis, P.; Baum, B.

1983-01-01

Terrestrial photovoltaic modules must undergo substantial reductions in cost in order to become economically attractive as practical devices for large scale production of electricity. Part of the cost reductions must be realized by the encapsulation materials that are used to package, protect, and support the solar cells, electrical interconnects, and other ancillary components. As many of the encapsulation materials are polymeric, cost reductions necessitate the use of low cost polymers. The performance and status of ethylene vinyl acetate, a low cost polymer that is being investigated as an encapsulation material for terrestrial photovoltaic modules, are described.

Cost estimates for flat plate and concentrator collector arrays

NASA Technical Reports Server (NTRS)

Shimada, K.

1982-01-01

The current module and installation costs for the U.S. National Photovoltaic Program's grid-connected systems are significantly higher than required for economic viability of this alternative. Attention is accordingly given to the prospects for installed module cost reductions in flat plate, linear focus Fresnel concentrator, and point focus Fresnel concentrator candidate systems. Cost projections indicate that all three systems would meet near-term and midterm goals, provided that module costs of $2.80/W(p) and $0.70/W(p), respectively, are met. The point focus Fresnel system emerges as the most viable for the near term.

Under-sampling in a Multiple-Channel Laser Vibrometry System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corey, Jordan

2007-03-01

Laser vibrometry is a technique used to detect vibrations on objects using the interference of coherent light with itself. Most vibrometry systems process only one target location at a time, but processing multiple locations simultaneously provides improved detection capabilities. Traditional laser vibrometry systems employ oversampling to sample the incoming modulated-light signal, however as the number of channels increases in these systems, certain issues arise such a higher computational cost, excessive heat, increased power requirements, and increased component cost. This thesis describes a novel approach to laser vibrometry that utilizes undersampling to control the undesirable issues associated with over-sampled systems. Undersamplingmore » allows for significantly less samples to represent the modulated-light signals, which offers several advantages in the overall system design. These advantages include an improvement in thermal efficiency, lower processing requirements, and a higher immunity to the relative intensity noise inherent in laser vibrometry applications. A unique feature of this implementation is the use of a parallel architecture to increase the overall system throughput. This parallelism is realized using a hierarchical multi-channel architecture based on off-the-shelf programmable logic devices (PLDs).« less

Silicon photonic Mach Zehnder modulators for next-generation short-reach optical communication networks

NASA Astrophysics Data System (ADS)

Lacava, C.; Liu, Z.; Thomson, D.; Ke, Li; Fedeli, J. M.; Richardson, D. J.; Reed, G. T.; Petropoulos, P.

2016-02-01

Communication traffic grows relentlessly in today's networks, and with ever more machines connected to the network, this trend is set to continue for the foreseeable future. It is widely accepted that increasingly faster communications are required at the point of the end users, and consequently optical transmission plays a progressively greater role even in short- and medium-reach networks. Silicon photonic technologies are becoming increasingly attractive for such networks, due to their potential for low cost, energetically efficient, high-speed optical components. A representative example is the silicon-based optical modulator, which has been actively studied. Researchers have demonstrated silicon modulators in different types of structures, such as ring resonators or slow light based devices. These approaches have shown remarkably good performance in terms of modulation efficiency, however their operation could be severely affected by temperature drifts or fabrication errors. Mach-Zehnder modulators (MZM), on the other hand, show good performance and resilience to different environmental conditions. In this paper we present a CMOS-compatible compact silicon MZM. We study the application of the modulator to short-reach interconnects by realizing data modulation using some relevant advanced modulation formats, such as 4-level Pulse Amplitude Modulation (PAM-4) and Discrete Multi-Tone (DMT) modulation and compare the performance of the different systems in transmission.

Low-cost manufacturing of the point focus concentrating module and its key component, the Fresnel lens. Final subcontract report, 31 January 1991--6 May 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saifee, T.; Konnerth, A. III

1991-11-01

Solar Kinetics, Inc. (SKI) has been developing point-focus concentrating PV modules since 1986. SKI is currently in position to manufacture between 200 to 600 kilowatts annually of the current design by a combination of manual and semi-automated methods. This report reviews the current status of module manufacture and specifies the required approach to achieve a high-volume manufacturing capability and low cost. The approach taken will include process development concurrent with module design for automated manufacturing. The current effort reviews the major manufacturing costs and identifies components and processes whose improvements would produce the greatest effect on manufacturability and cost reduction.more » The Fresnel lens is one such key component. Investigating specific alternative manufacturing methods and sources has substantially reduced the lens costs and has exceeded the DOE cost-reduction goals. 15 refs.« less

Creating an automated tool for measuring software cohesion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tutton, J.M.; Zucconi, L.

1994-05-06

Program modules with high complexity tend to be more error prone and more difficult to understand. These factors increase maintenance and enhancement costs. Hence, a tool that can help programmers determine a key factor in module complexity should be very useful. Our goal is to create a software tool that will automatically give a quantitative measure of the cohesiveness of a given module, and hence give us an estimate of the {open_quotes}maintainability{close_quotes} of that module. The Tool will use a metric developed by Professors Linda M. Ott and James M. Bieman. The Ott/Bieman metric gives quantitative measures that indicate themore » degree of functional cohesion using abstract data slices.« less

Low cost solar array project production process and equipment task. A Module Experimental Process System Development Unit (MEPSDU)

NASA Technical Reports Server (NTRS)

1981-01-01

Technical readiness for the production of photovoltaic modules using single crystal silicon dendritic web sheet material is demonstrated by: (1) selection, design and implementation of solar cell and photovoltaic module process sequence in a Module Experimental Process System Development Unit; (2) demonstration runs; (3) passing of acceptance and qualification tests; and (4) achievement of a cost effective module.

Evaluation of the InFocus TVT-6000 LCTV

NASA Astrophysics Data System (ADS)

Duffey, Jason N.; Jones, Brian K.; Gregory, Don A.; McClain, John L., Jr.

1994-03-01

Liquid crystal televisions have become increasingly popular as low-cost spatial light modulators. While the early devices suffered from poor resolution and low contrast, recent models compare favorably to the more traditional (and expensive) modulators. One of the most recent LCTVs is found in the InFocus TVT-6000 television projector. The panels in this projector have 480 X 440 pixels with a 1.32' diagonal clear aperture. A wavefront splitting interferometer has been constructed and analyzed for measuring the complex characteristics of these modulators, including phase and amplitude coupling. The results of this evaluation will be presented.

Evaluating the economic viability of CdTe/CIS and CIGS/CIS tandem photovoltaic modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nanayakkara, Sanjini U.; Horowitz, Kelsey; Kanevce, Ana

In this paper, we analyze the potential cost competitiveness of two frameless, glass–glass thin-film tandem photovoltaic module structures, cadmium telluride (CdTe)/CuInSe 2 (CIS) and CuIn 0.3Ga 0.7Se 2 (CIGS)/CIS, based on the demonstrated cost of manufacturing the respective component cell technologies in high volume. To consider multiple economic scenarios, we base the CdTe/CIS module efficiency on the current industrial production of CdTe modules, while for CIGS/CIS, we use an aspirational estimate for CIGS efficiency. We focus on four-terminal mechanically stacked structures, thus avoiding the need to achieve current matching between the two cells. The top cell in such a tandemmore » must have a transparent back contact, which has not been successfully implemented to date. However, for the purpose of understanding the economic viability of both tandems, we assume that this can be implemented at a cost similar to that of sputtered indium tin oxide. The cost of both tandem module structures was found to be nearly identical on an equal-area basis and approximately $30/m 2 higher than the single-junction alternatives. Both tandem modules are about 4% (absolute) more efficient than a module by using the top-cell material alone. We find that these tandem modules might reduce total system cost by as much as 11% in applications having a high area-related balance-of-system cost, such as area-constrained residential systems; however, the relative advantage of tandems decreases in the cases where balance-of-system costs are lower, such as in commercial and utility scale systems.« less

Evaluating the economic viability of CdTe/CIS and CIGS/CIS tandem photovoltaic modules

DOE PAGES

Nanayakkara, Sanjini U.; Horowitz, Kelsey; Kanevce, Ana; ...

2017-01-20

In this paper, we analyze the potential cost competitiveness of two frameless, glass–glass thin-film tandem photovoltaic module structures, cadmium telluride (CdTe)/CuInSe 2 (CIS) and CuIn 0.3Ga 0.7Se 2 (CIGS)/CIS, based on the demonstrated cost of manufacturing the respective component cell technologies in high volume. To consider multiple economic scenarios, we base the CdTe/CIS module efficiency on the current industrial production of CdTe modules, while for CIGS/CIS, we use an aspirational estimate for CIGS efficiency. We focus on four-terminal mechanically stacked structures, thus avoiding the need to achieve current matching between the two cells. The top cell in such a tandemmore » must have a transparent back contact, which has not been successfully implemented to date. However, for the purpose of understanding the economic viability of both tandems, we assume that this can be implemented at a cost similar to that of sputtered indium tin oxide. The cost of both tandem module structures was found to be nearly identical on an equal-area basis and approximately $30/m 2 higher than the single-junction alternatives. Both tandem modules are about 4% (absolute) more efficient than a module by using the top-cell material alone. We find that these tandem modules might reduce total system cost by as much as 11% in applications having a high area-related balance-of-system cost, such as area-constrained residential systems; however, the relative advantage of tandems decreases in the cases where balance-of-system costs are lower, such as in commercial and utility scale systems.« less

A wide-angle camera module for disposable endoscopy

NASA Astrophysics Data System (ADS)

Shim, Dongha; Yeon, Jesun; Yi, Jason; Park, Jongwon; Park, Soo Nam; Lee, Nanhee

2016-08-01

A wide-angle miniaturized camera module for disposable endoscope is demonstrated in this paper. A lens module with 150° angle of view (AOV) is designed and manufactured. All plastic injection-molded lenses and a commercial CMOS image sensor are employed to reduce the manufacturing cost. The image sensor and LED illumination unit are assembled with a lens module. The camera module does not include a camera processor to further reduce its size and cost. The size of the camera module is 5.5 × 5.5 × 22.3 mm3. The diagonal field of view (FOV) of the camera module is measured to be 110°. A prototype of a disposable endoscope is implemented to perform a pre-clinical animal testing. The esophagus of an adult beagle dog is observed. These results demonstrate the feasibility of a cost-effective and high-performance camera module for disposable endoscopy.

The 40 KW of Solar Cell Modules for the Large Scale Production Task a Low Cost Silicon Solar Array Project

NASA Technical Reports Server (NTRS)

Jones, G. T.

1977-01-01

Forty kilowatts of solar cell modules was produced in this program. This is equivalent to 4123 modules. The average power output per module was 9.7 watts at 16.5 volts, 60 C and 100 mW/sq cm. The peak production rate was 200 modules per week which is equal to 1.9 kW per week. This rate was sustained for over four and one-half months and is equivalent to 100 kW per year. This final report covers the solar cell module design, electrical and power performance, module preproduction environmental test results, production and shipping schedule, program summary, and delivery. A cost analysis section is written. Particular emphasis on the percentage of labor and material utilized in constructing a solar cell module is presented. Also included are cost reduction recommendations.

High efficiency low cost monolithic module for SARSAT distress beacons

NASA Technical Reports Server (NTRS)

Petersen, Wendell C.; Siu, Daniel P.

1992-01-01

The program objectives were to develop a highly efficient, low cost RF module for SARSAT beacons; achieve significantly lower battery current drain, amount of heat generated, and size of battery required; utilize MMIC technology to improve efficiency, reliability, packaging, and cost; and provide a technology database for GaAs based UHF RF circuit architectures. Presented in viewgraph form are functional block diagrams of the SARSAT distress beacon and beacon RF module as well as performance goals, schematic diagrams, predicted performances, and measured performances for the phase modulator and power amplifier.

A Short Progress Report on High-Efficiency Perovskite Solar Cells.

PubMed

Tang, He; He, Shengsheng; Peng, Chuangwei

2017-12-01

Faced with the increasingly serious energy and environmental crisis in the world nowadays, the development of renewable energy has attracted increasingly more attention of all countries. Solar energy as an abundant and cheap energy is one of the most promising renewable energy sources. While high-performance solar cells have been well developed in the last couple of decades, the high module cost largely hinders wide deployment of photovoltaic devices. In the last 10 years, this urgent demand for cost-effective solar cells greatly facilitates the research of solar cells. This paper reviews the recent development of cost-effective and high-efficient solar cell technologies. This report paper covers low-cost and high-efficiency perovskite solar cells. The development and the state-of-the-art results of perovskite solar cell technologies are also introduced.

SMART: The Future of Spaceflight Avionics

NASA Technical Reports Server (NTRS)

Alhorn, Dean C.; Howard, David E.

2010-01-01

A novel avionics approach is necessary to meet the future needs of low cost space and lunar missions that require low mass and low power electronics. The current state of the art for avionics systems are centralized electronic units that perform the required spacecraft functions. These electronic units are usually custom-designed for each application and the approach compels avionics designers to have in-depth system knowledge before design can commence. The overall design, development, test and evaluation (DDT&E) cycle for this conventional approach requires long delivery times for space flight electronics and is very expensive. The Small Multi-purpose Advanced Reconfigurable Technology (SMART) concept is currently being developed to overcome the limitations of traditional avionics design. The SMART concept is based upon two multi-functional modules that can be reconfigured to drive and sense a variety of mechanical and electrical components. The SMART units are key to a distributed avionics architecture whereby the modules are located close to or right at the desired application point. The drive module, SMART-D, receives commands from the main computer and controls the spacecraft mechanisms and devices with localized feedback. The sensor module, SMART-S, is used to sense the environmental sensors and offload local limit checking from the main computer. There are numerous benefits that are realized by implementing the SMART system. Localized sensor signal conditioning electronics reduces signal loss and overall wiring mass. Localized drive electronics increase control bandwidth and minimize time lags for critical functions. These benefits in-turn reduce the main processor overhead functions. Since SMART units are standard flight qualified units, DDT&E is reduced and system design can commence much earlier in the design cycle. Increased production scale lowers individual piece part cost and using standard modules also reduces non-recurring costs. The benefit list continues, but the overall message is already evident: the SMART concept is an evolution in spacecraft avionics. SMART devices have the potential to change the design paradigm for future satellites, spacecraft and even commercial applications.

Low cost, small form factor, and integration as the key features for the optical component industry takeoff

NASA Astrophysics Data System (ADS)

Schiattone, Francesco; Bonino, Stefano; Gobbi, Luigi; Groppi, Angelamaria; Marazzi, Marco; Musio, Maurizio

2003-04-01

In the past the optical component market has been mainly driven by performances. Today, as the number of competitors has drastically increased, the system integrators have a wide range of possible suppliers and solutions giving them the possibility to be more focused on cost and also on footprint reduction. So, if performances are still essential, low cost and Small Form Factor issues are becoming more and more crucial in selecting components. Another evolution in the market is the current request of the optical system companies to simplify the supply chain in order to reduce the assembling and testing steps at system level. This corresponds to a growing demand in providing subassemblies, modules or hybrid integrated components: that means also Integration will be an issue in which all the optical component companies will compete to gain market shares. As we can see looking several examples offered by electronic market, to combine low cost and SFF is a very challenging task but Integration can help in achieving both features. In this work we present how these issues could be approached giving examples of some advanced solutions applied to LiNbO3 modulators. In particular we describe the progress made on automation, new materials and low cost fabrication methods for the parts. We also introduce an approach in integrating optical and electrical functionality on LiNbO3 modulators including RF driver, bias control loop, attenuator and photodiode integrated in a single device.

Stereotactic body radiotherapy for lung cancer: how much does it really cost?

PubMed

Lievens, Yolande; Obyn, Caroline; Mertens, Anne-Sophie; Van Halewyck, Dries; Hulstaert, Frank

2015-03-01

Despite the lack of randomized evidence, stereotactic body radiotherapy (SBRT) is being accepted as superior to conventional radiotherapy for patients with T1-2N0 non-small-cell lung cancer in the periphery of the lung and unfit or unwilling to undergo surgery. To introduce SBRT in a system of coverage with evidence development, a correct financing had to be determined. A time-driven activity-based costing model for radiotherapy was developed. Resource cost calculation of all radiotherapy treatments, standard and innovative, was conducted in 10 Belgian radiotherapy centers in the second half of 2012. The average cost of lung SBRT across the 10 centers (6221&OV0556;) is in the range of the average costs of standard fractionated 3D-conformal radiotherapy (5919&OV0556;) and intensity-modulated radiotherapy (7379&OV0556;) for lung cancer. Hypofractionated 3D-conformal radiotherapy and intensity-modulated radiotherapy schemes are less costly (3993&OV0556; respectively 4730&OV0556;). The SBRT cost increases with the number of fractions and is highly dependent of personnel and equipment use. SBRT cost varies more by centre than conventional radiotherapy cost, reflecting different technologies, stages in the learning curve and a lack of clear guidance in this field. Time-driven activity-based costing of radiotherapy is feasible in a multicentre setup, resulting in real-life resource costs that can form the basis for correct reimbursement schemes, supporting an early yet controlled introduction of innovative radiotherapy techniques in clinical practice.

[Data Collection and Assessment of Costs for Prevention And Health Promotion Programs: Development of a Concept Illustrated with 'Promotion of Physical Activity'].

PubMed

Korber, Katharina; Wolfenstetter, Silke Britta

2017-03-08

It is a desirable medical as well as health economic objective to achieve the best possible health effects with given financial resources. Estimating the costs of intervention programs is complex and not always possible in advance. One possibility to obtain information on costs or cost effectiveness of certain interventions is to assess programs already in existence. The aim of this article was to develop a simple, easy to understand and practical possibility of documenting costs of prevention and health promotion programs. Based on the fundamentals necessary for cost assessment, a questionnaire and a module to document the consumed resources and the resultant costs were developed. These were applied and improved within a pre-test. The developed cost module is as follows: In the left column, 5 key cost categories are listed: personnel, rooms, equipment and process, management, other costs. The cost module is a compromise between different objectives that are difficult to reconcile. On the one hand, the costs should be documented as detailed as possible and on the other, the module must be very simple to implement, as otherwise it will not be used in practice. For this purpose, it might also be useful to develop a module for each stakeholder that is aligned as closely as possible to his or her special activities. All feedback and suggestions from the pre-test were incorporated. However, some of the feedback points were project specific. Here an attempt was made to find a compromise between detail and practicality. This was done by implementing more detailed descriptions and examples in the manual. The presented module is very general. This also is a great advantage because it can be used to document the costs of completely different stakeholders. Thus, the concept presented here for cost assessment provides a first and essential component for a detailed documentation of program costs and provides the potential to check comparability and transferability of those prevention programs. © Georg Thieme Verlag KG Stuttgart · New York.

Repair of Composites: Design Choices Leading to Lower Life-Cycle Cost

NASA Astrophysics Data System (ADS)

Kassapoglou, Christos; Rangelov, Konstantin; Rangelov, Svilen

2017-08-01

The fabrication cost of composite aircraft structures is revisited and the effect of part size on cost is examined with emphasis on design decisions which affect the ease of (bonded) repair and the total cost of the part and subsequent repairs. The case of moderately loaded stiffened fuselage or wing panels under compression is analysed in detail and the fabrication cost of the panel made as a single piece or as an assembly of smaller identical components or modules is determined. The cost of special purpose repairs for two different damage sizes is compared to removing and replacing damaged modules. Hand layup and automated processing are compared. It is found that for certain repair sizes removing and replacing modules leads to lower overall cost as compared to applying a special purpose repair.

Pseudo-Random Modulation of a Laser Diode for Generating Ultrasonic Longitudinal Waves

NASA Technical Reports Server (NTRS)

Madaras, Eric I.; Anatasi, Robert F.

2004-01-01

Laser generated ultrasound systems have historically been more complicated and expensive than conventional piezoelectric based systems, and this fact has relegated the acceptance of laser based systems to niche applications for which piezoelectric based systems are less suitable. Lowering system costs, while improving throughput, increasing ultrasound signal levels, and improving signal-to-noise are goals which will help increase the general acceptance of laser based ultrasound. One current limitation with conventional laser generated ultrasound is a material s damage threshold limit. Increasing the optical power to generate more signal eventually damages the material being tested due to rapid, high heating. Generation limitations for laser based ultrasound suggests the use of pulse modulation techniques as an alternate generation method. Pulse modulation techniques can spread the laser energy over time or space, thus reducing laser power densities and minimizing damage. Previous experiments by various organizations using spatial or temporal pulse modulation have been shown to generate detectable surface, plate, and bulk ultrasonic waves with narrow frequency bandwidths . Using narrow frequency bandwidths improved signal detectability, but required the use of expensive and powerful lasers and opto-electronic systems. The use of a laser diode to generate ultrasound is attractive because of its low cost, small size, light weight, simple optics and modulation capability. The use of pulse compression techniques should allow certain types of laser diodes to produce usable ultrasonic signals. The method also does not need to be limited to narrow frequency bandwidths. The method demonstrated here uses a low power laser diode (approximately 150 mW) that is modulated by controlling the diode s drive current and the resulting signal is recovered by cross correlation. A potential application for this system which is briefly demonstrated is in detecting signals in thick composite materials where attenuation is high and signal amplitude and bandwidth are at a premium.

Capacity upgrade in short-reach optical fibre networks: simultaneous 4-PAM 20 Gbps data and polarization-modulated PPS clock signal using a single VCSEL carrier

NASA Astrophysics Data System (ADS)

Isoe, G. M.; Wassin, S.; Gamatham, R. R. G.; Leitch, A. W. R.; Gibbon, T. B.

2017-11-01

In this work, a four-level pulse amplitude modulation (4-PAM) format with a polarization-modulated pulse per second (PPS) clock signal using a single vertical cavity surface emitting laser (VCSEL) carrier is for the first time experimentally demonstrated. We propose uncomplex alternative technique for increasing capacity and flexibility in short-reach optical communication links through multi-signal modulation onto a single VCSEL carrier. A 20 Gbps 4-PAM data signal is directly modulated onto a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm, therefore, doubling the network bit rate. Carrier spectral efficiency is further maximized by exploiting the inherent orthogonal polarization switching of the VCSEL carrier with changing bias in transmission of a PPS clock signal. We, therefore, simultaneously transmit a 20 Gbps 4-PAM data signal and a polarization-based PPS clock signal using a single VCSEL carrier. It is the first time a signal VCSEL carrier is reported to simultaneously transmit a directly modulated 20 Gbps 4-PAM data signal and a polarization-based PPS clock signal. We further demonstrate on the design of a software-defined digital signal processing (DSP)-assisted receiver as an alternative to costly receiver hardware. Experimental results show that a 3.21 km fibre transmission with simultaneous 20 Gbps 4-PAM data signal and polarization-based PPS clock signal introduced a penalty of 3.76 dB. The contribution of polarization-based PPS clock signal to this penalty was found out to be 0.41 dB. Simultaneous distribution of data and timing clock signals over shared network infrastructure significantly increases the aggregated data rate at different optical network units (ONUs), without costly investment.

Automated array assembly

NASA Technical Reports Server (NTRS)

Williams, B. F.

1976-01-01

Manufacturing techniques are evaluated using expenses based on experience and studying basic cost factors for each step to evaluate expenses from a first-principles point of view. A formal cost accounting procedure is developed which is used throughout the study for cost comparisons. The first test of this procedure is a comparison of its predicted costs for array module manufacturing with costs from a study which is based on experience factors. A manufacturing cost estimate for array modules of $10/W is based on present-day manufacturing techniques, expenses, and materials costs.

Commercial/industrial photovoltaic module and array requirement study. Low-cost solar array project engineering area

NASA Technical Reports Server (NTRS)

1981-01-01

Design requirements for photovoltaic modules and arrays used in commercial and industrial applications were identified. Building codes and referenced standards were reviewed for their applicability to commercial and industrial photovoltaic array installation. Four general installation types were identified - integral (replaces roofing), direct (mounted on top of roofing), stand-off (mounted away from roofing), and rack (for flat or low slope roofs, or ground mounted). Each of the generic mounting types can be used in vertical wall mounting systems. This implies eight mounting types exist in the commercial/industrial sector. Installation costs were developed for these mounting types as a function of panel/module size. Cost drivers were identified. Studies were performed to identify optimum module shapes and sizes and operating voltage cost drivers. The general conclusion is that there are no perceived major obstacles to the use of photovoltaic modules in commercial/industrial arrays.

Documentation of the analysis of the benefits and costs of aeronautical research and technology models, volume 1

NASA Technical Reports Server (NTRS)

Bobick, J. C.; Braun, R. L.; Denny, R. E.

1979-01-01

The analysis of the benefits and costs of aeronautical research and technology (ABC-ART) models are documented. These models were developed by NASA for use in analyzing the economic feasibility of applying advanced aeronautical technology to future civil aircraft. The methodology is composed of three major modules: fleet accounting module, airframe manufacturing module, and air carrier module. The fleet accounting module is used to estimate the number of new aircraft required as a function of time to meet demand. This estimation is based primarily upon the expected retirement age of existing aircraft and the expected change in revenue passenger miles demanded. Fuel consumption estimates are also generated by this module. The airframe manufacturer module is used to analyze the feasibility of the manufacturing the new aircraft demanded. The module includes logic for production scheduling and estimating manufacturing costs. For a series of aircraft selling prices, a cash flow analysis is performed and a rate of return on investment is calculated. The air carrier module provides a tool for analyzing the financial feasibility of an airline purchasing and operating the new aircraft. This module includes a methodology for computing the air carrier direct and indirect operating costs, performing a cash flow analysis, and estimating the internal rate of return on investment for a set of aircraft purchase prices.

The development and application of composite complexity models and a relative complexity metric in a software maintenance environment

NASA Technical Reports Server (NTRS)

Hops, J. M.; Sherif, J. S.

1994-01-01

A great deal of effort is now being devoted to the study, analysis, prediction, and minimization of software maintenance expected cost, long before software is delivered to users or customers. It has been estimated that, on the average, the effort spent on software maintenance is as costly as the effort spent on all other software costs. Software design methods should be the starting point to aid in alleviating the problems of software maintenance complexity and high costs. Two aspects of maintenance deserve attention: (1) protocols for locating and rectifying defects, and for ensuring that noe new defects are introduced in the development phase of the software process; and (2) protocols for modification, enhancement, and upgrading. This article focuses primarily on the second aspect, the development of protocols to help increase the quality and reduce the costs associated with modifications, enhancements, and upgrades of existing software. This study developed parsimonious models and a relative complexity metric for complexity measurement of software that were used to rank the modules in the system relative to one another. Some success was achieved in using the models and the relative metric to identify maintenance-prone modules.

Economically Sustainable Scaling of Photovoltaics to Meet Climate Targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Needleman, David Berney; Poindexter, Jeremy R.; Kurchin, Rachel C.

To meet climate goals, photovoltaics (PV) deployment will have to grow rapidly over the next fifteen years. We identify two barriers to this growth: scale-up of manufacturing capacity and the cost of PV module production. We explore several technoeconomic approaches to overcoming these barriers and identify deep reductions in the capital intensity (capex) of PV module manufacturing and large increases in module efficiency as the most promising routes to rapid deployment. Given the lag inherent in rolling out new technology, we explore an approach where growth is fueled by debt or subsidies in the short-term and technological advances in themore » medium term. Finally, we analyze the current capex structure of crystalline silicon PV module manufacturing to identify potential savings.« less

Experiment module concepts study. Volume 1: Management summary

NASA Technical Reports Server (NTRS)

1970-01-01

The minimum number of standardized (common) module concepts that will satisfy the experiment program for manned space stations at least cost is investigated. The module interfaces with other elements such as the space shuttle, ground stations, and the experiments themselves are defined. The total experiment module program resource and test requirements are also considered. The minimum number of common module concepts that will satisfy the program at least cost is found to be three, plus a propulsion slice and certain experiment-peculiar integration hardware. The experiment modules rely on the space station for operational, maintenance, and logistic support. They are compatible with both expendable and shuttle launch vehicles, and with servicing by shuttle, tug, or directly from the space station. A total experiment module program cost of approximately $2319M under the study assumptions is indicated. This total is made up of $838M for experiment module development and production, $806M for experiment equipment, and $675M for interface hardware, experiment integration, launch and flight operations, and program management and support.

A geochemical module for "AMDTreat" to compute caustic quantity, effluent quantity, and sludge volume

USGS Publications Warehouse

Cravotta, Charles A.; Parkhurst, David L.; Means, Brent P; McKenzie, Bob; Morris, Harry; Arthur, Bill

2010-01-01

Treatment with caustic chemicals typically is used to increase pH and decrease concentrations of dissolved aluminum, iron, and/or manganese in largevolume, metal-laden discharges from active coal mines. Generally, aluminum and iron can be removed effectively at near-neutral pH (6 to 8), whereas active manganese removal requires treatment to alkaline pH (~10). The treatment cost depends on the specific chemical used (NaOH, CaO, Ca(OH)2, Na2CO3, or NH3) and increases with the quantities of chemical added and sludge produced. The pH and metals concentrations do not change linearly with the amount of chemical added. Consequently, the amount of caustic chemical needed to achieve a target pH and the corresponding effluent composition and sludge volume can not be accurately determined without empirical titration data or the application of geochemical models to simulate the titration of the discharge water with caustic chemical(s). The AMDTreat computer program (http://amd.osmre.gov/ ) is widely used to compute costs for treatment of coal-mine drainage. Although AMDTreat can use results of empirical titration with industrial grade caustic chemicals to compute chemical costs for treatment of net-acidic or net-alkaline mine drainage, such data are rarely available. To improve the capability of AMDTreat to estimate (1) the quantity and cost of caustic chemicals to attain a target pH, (2) the concentrations of dissolved metals in treated effluent, and (3) the volume of sludge produced by the treatment, a titration simulation is being developed using the geochemical program PHREEQC (wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/) that will be coupled as a module to AMDTreat. The simulated titration results can be compared with or used in place of empirical titration data to estimate chemical quantities and costs. This paper describes the development, evaluation, and potential utilization of the PHREEQC titration module for AMDTreat.

Photovoltaics: Energy for the New Millenium

NASA Astrophysics Data System (ADS)

Surek, Thomas

2000-04-01

Photovoltaics (PV) is a semiconductor-based technology that directly converts sunlight to electricity. The stimulus for terrestrial PV started more than 25 years ago in response to the oil crises of the 1970s, which resulted in major government programs in the United States, Europe, Japan, and elsewhere. Ongoing concerns with the global environment, as well as the worldwide efforts to seek alternate, indigenous sources of energy, continue to drive the investment in PV research and deployment. Today, the manufacture, sale, and use of PV has become a billion-dollar industry worldwide, with nearly 200 megawatts (MW) of PV modules shipped in 1999. The twenty five years of research and development led to the discovery of new PV materials, devices, and fabrication approaches; continuing improvements in the efficiency and reliability of solar cells and modules; and lower PV module and system costs. This talk reviews the rapid progress that has occurred in PV technology from the laboratory to the marketplace, including reviews of the leading technology options, status and issues, and key industry players. New processes for fabricating PV materials and devices, and innovative PV approaches with low-cost potential are elements of an ongoing research program aimed at future advancements in PV cost and performance While major market opportunities continue to exist in the developing countries, where sizable populations are without any electricity, today's manufacturing expansions are fueled by market initiatives for grid-connected PV in residential and commercial buildings. The combinations of increased production capacities, with the attendant cost reductions as a result of economies of scale, are expected to lead to sustainable markets. A key to achieving the ultimate potential of PV is to continue to increase the sunlight-to-electricity conversion efficiencies and translate the laboratory successes to cost-competitive products. Building a robust technology base is essential to overcoming this high-risk transition. Then PV will make a globally significant contribution to our energy supply and environment.

Hospital financing: calculating inpatient capital costs in Germany with a comparative view on operating costs and the English costing scheme.

PubMed

Vogl, Matthias

2014-04-01

The paper analyzes the German inpatient capital costing scheme by assessing its cost module calculation. The costing scheme represents the first separated national calculation of performance-oriented capital cost lump sums per DRG. The three steps in the costing scheme are reviewed and assessed: (1) accrual of capital costs; (2) cost-center and cost category accounting; (3) data processing for capital cost modules. The assessment of each step is based on its level of transparency and efficiency. A comparative view on operating costing and the English costing scheme is given. Advantages of the scheme are low participation hurdles, low calculation effort for G-DRG calculation participants, highly differentiated cost-center/cost category separation, and advanced patient-based resource allocation. The exclusion of relevant capital costs, nontransparent resource allocation, and unclear capital cost modules, limit the managerial relevance and transparency of the capital costing scheme. The scheme generates the technical premises for a change from dual financing by insurances (operating costs) and state (capital costs) to a single financing source. The new capital costing scheme will intensify the discussion on how to solve the current investment backlog in Germany and can assist regulators in other countries with the introduction of accurate capital costing. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Digital intermediate frequency QAM modulator using parallel processing

DOEpatents

Pao, Hsueh-Yuan [Livermore, CA; Tran, Binh-Nien [San Ramon, CA

2008-05-27

The digital Intermediate Frequency (IF) modulator applies to various modulation types and offers a simple and low cost method to implement a high-speed digital IF modulator using field programmable gate arrays (FPGAs). The architecture eliminates multipliers and sequential processing by storing the pre-computed modulated cosine and sine carriers in ROM look-up-tables (LUTs). The high-speed input data stream is parallel processed using the corresponding LUTs, which reduces the main processing speed, allowing the use of low cost FPGAs.

National Stormwater Calculator: Low Impact Development ...

EPA Pesticide Factsheets

The National Stormwater Calculator (NSC) makes it easy to estimate runoff reduction when planning a new development or redevelopment site with low impact development (LID) stormwater controls. The Calculator is currently deployed as a Windows desktop application. The Calculator is organized as a wizard style application that walks the user through the steps necessary to perform runoff calculations on a single urban sub-catchment of 10 acres or less in size. Using an interactive map, the user can select the sub-catchment location and the Calculator automatically acquires hydrologic data for the site.A new LID cost estimation module has been developed for the Calculator. This project involved programming cost curves into the existing Calculator desktop application. The integration of cost components of LID controls into the Calculator increases functionality and will promote greater use of the Calculator as a stormwater management and evaluation tool. The addition of the cost estimation module allows planners and managers to evaluate LID controls based on comparison of project cost estimates and predicted LID control performance. Cost estimation is accomplished based on user-identified size (or auto-sizing based on achieving volume control or treatment of a defined design storm), configuration of the LID control infrastructure, and other key project and site-specific variables, including whether the project is being applied as part of new development or redevelopm

Recent developments in photovoltaic energy by ERDA/NASA-LeRC

NASA Technical Reports Server (NTRS)

Deyo, J. N.

1977-01-01

Application development activities were designed to stimulate the market for photovoltaics so that as costs are reduced there will be an increasing market demand to encourage the expansion of industrial solar array production capacity. Supporting these application development activities are tasks concerned with: (1) establishing standards and methodology for terrestrial solar cell calibration; (2) conducting standard and diagnostic measurements on solar cells and modules; and (3) conducting real time and accelerated testing of solar cell modules and materials of construction under outdoor sunlight conditions.

Space Experiment Module: A new low-cost capability for education payloads

NASA Technical Reports Server (NTRS)

Goldsmith, Theodore C.; Lewis, Ruthan

1995-01-01

The Space Experiment Module (SEM) concept is one of a number of education initiatives being pursued by the NASA Shuttle Small Payloads Project (SSPP) in an effort to increase educational access to space by means of Space Shuttle Small Payloads and associated activities. In the SEM concept, NASA will provide small containers ('modules') which can accommodate small zero-gravity experiments designed and constructed by students. A number, (nominally ten), of the modules will then be flown in an existing Get Away Special (GAS) carrier on the Shuttle for a flight of 5 to 10 days. In addition to the module container, the NASA carrier system will provide small amounts of electrical power and a computer system for controlling the operation of the experiments and recording experiment data. This paper describes the proposed SEM carrier system and program approach.

Cu(In,Ga)(Se,S)2 solar cell research in Solar Frontier: Progress and current status

NASA Astrophysics Data System (ADS)

Kato, Takuya

2017-04-01

As the largest manufacturer of Cu(In,Ga)(Se,S)2 (CIGS) thin-film photovoltaic modules with more than 1 GW/year production volume, Solar Frontier K.K. has continuously improved module performance and small-area cell efficiencies in the laboratory. Because of our low-cost and environmentally-friendly process, Solar Frontier’s CIGS is a promising technology for the mass production of photovoltaic modules to fill ever-increasing demand. Recently we have achieved certified efficiencies of 22.3 and 22.0% on CdS-buffered and Cd-free buffered small-area cells, respectively, as well as 18.6% on a Cd-free mini-module. In this paper, a review of our CIGS technology and recent progress on the development of the module and the small-area cell is presented.

Chemical Genomics Profiling of Environmental Chemical Modulation of Human Nuclear Receptors

EPA Science Inventory

The large and increasing number of chemicals released into the environment demand more efficient and cost effective approaches for assessing environmental chemical toxicity. The U.S. Tox21 program has responded to this challenge by proposing alternative strategies for toxicity te...

On the Path to SunShot - The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodhouse, Michael; Jones-Albertus, Rebecca; Feldman, David

2016-05-01

Although tremendous progress has been made in reducing the cost of PV systems, additional LCOE reductions of 40%–50% between 2015 and 2020 will be required to reach the SunShot Initiative’s targets (see Woodhouse et al. 2016). Understanding the tradeoffs between installed prices and other PV system characteristics—such as module efficiency, module degradation rate, and system lifetime—are vital. For example, with 29%-efficient modules and high reliability (a 50-year lifetime and a 0.2%/year module degradation rate), a residential PV system could achieve the SunShot LCOE goal with modules priced at almost $1.20/W. But change the lifetime to 10 years and the degradationmore » rate to 2%/year, and the system would need those very high-efficiency modules at zero cost to achieve the same LCOE. Although these examples are extreme, they serve to illustrate the wide range of technological combinations that could help drive PV toward the LCOE goals. SunShot’s PV roadmaps illustrate specific potential pathways to the target cost reductions.« less

AMDTreat 5.0+ with PHREEQC titration module to compute caustic chemical quantity, effluent quality, and sludge volume

USGS Publications Warehouse

Cravotta, Charles A.; Means, Brent P; Arthur, Willam; McKenzie, Robert M; Parkhurst, David L.

2015-01-01

Alkaline chemicals are commonly added to discharges from coal mines to increase pH and decrease concentrations of acidity and dissolved aluminum, iron, manganese, and associated metals. The annual cost of chemical treatment depends on the type and quantities of chemicals added and sludge produced. The AMDTreat computer program, initially developed in 2003, is widely used to compute such costs on the basis of the user-specified flow rate and water quality data for the untreated AMD. Although AMDTreat can use results of empirical titration of net-acidic or net-alkaline effluent with caustic chemicals to accurately estimate costs for treatment, such empirical data are rarely available. A titration simulation module using the geochemical program PHREEQC has been incorporated with AMDTreat 5.0+ to improve the capability of AMDTreat to estimate: (1) the quantity and cost of caustic chemicals to attain a target pH, (2) the chemical composition of the treated effluent, and (3) the volume of sludge produced by the treatment. The simulated titration results for selected caustic chemicals (NaOH, CaO, Ca(OH)2, Na2CO3, or NH3) without aeration or with pre-aeration can be compared with or used in place of empirical titration data to estimate chemical quantities, treated effluent composition, sludge volume (precipitated metals plus unreacted chemical), and associated treatment costs. This paper describes the development, evaluation, and potential utilization of the PHREEQC titration module with the new AMDTreat 5.0+ computer program available at http://www.amd.osmre.gov/.

Degradation of Silicone Encapsulants in CPV Optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cai, Can; Miller, David C.; Tappan, Ian A.

High efficiency multijunction solar cells in terrestrial concentrator photovoltaic (CPV) modules are becoming an increasingly cost effective and viable option in utility scale power generation. As with other utility scale photovoltaics, CPV modules need to guarantee operational lifetimes of at least 25 years. The reliability of optical elements in CPV modules poses a unique materials challenge due to the increased UV irradiance and enhanced temperature cycling associated with concentrated solar flux. The polymeric and thin film materials used in the optical elements are especially susceptible to UV damage, diurnal temperature cycling and active chemical species from the environment. We usedmore » fracture mechanics approaches to study the degradation modes including: the adhesion between the encapsulant and the cell or secondary optical element; and the cohesion of the encapsulant itself. Understanding the underlying mechanisms of materials degradation under elevated stress conditions is critical for commercialization of CPV technology and can offer unique insights into degradation modes in similar encapsulants used in other photovoltaic modules.« less

Degradation of Silicone Encapsulants in CPV Optics: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, David C.; Tappan, Ian A.; Cai, Can

High efficiency multijunction solar cells in terrestrial concentrator photovoltaic (CPV) modules are becoming an increasingly cost effective and viable option in utility scale power generation. As with other utility scale photovoltaics, CPV modules need to guarantee operational lifetimes of at least 25 years. The reliability of optical elements in CPV modules poses a unique materials challenge due to the increased UV irradiance and enhanced temperature cycling associated with concentrated solar flux. The polymeric and thin film materials used in the optical elements are especially susceptible to UV damage, diurnal temperature cycling and active chemical species from the environment. We usedmore » fracture mechanics approaches to study the degradation modes including: the adhesion between the encapsulant and the cell or secondary optical element; and the cohesion of the encapsulant itself. Understanding the underlying mechanisms of materials degradation under elevated stress conditions is critical for commercialization of CPV technology and can offer unique insights into degradation modes in similar encapsulants used in other photovoltaic modules.« less

Evaluating the causes of photovoltaics cost reduction: Why is PV different?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trancik, Jessika; McNerney, James; Kavlak, Goksin

The goals of this project were to quantify sources of cost reduction in photovoltaics (PV), improve theories of technological evolution, develop new analytical methods, and formu- late guidelines for continued cost reduction in photovoltaics. A number of explanations have been suggested for why photovoltaics have come down in cost rapidly over time, including increased production rates, significant R&D expenditures, heavy patenting ac- tivity, decreasing material and input costs, scale economies, reduced plant construction costs, and higher conversion efficiencies. We classified these proposed causes into low- level factors and high-level drivers. Low-level factors include technical characteristics, such as module efficiency ormore » wafer area, which are easily posed in terms of variables of a cost equation. High-level factors include scale economies, research and development (R&D), and learning-by-doing.« less

A Self-Instructional Course in Student Financial Aid Administration. Module 7: Calculating Cost of Attendance. Second Edition.

ERIC Educational Resources Information Center

Washington Consulting Group, Inc., Washington, DC.

The seventh module in a 17-module self-instructional course on student financial aid administration (designed for novice student financial aid administrators and other personnel) teaches how to calculate the cost of attendance. It provides a systematic introduction to the management of federal financial aid programs authorized by the Higher…

An improved classification tree analysis of high cost modules based upon an axiomatic definition of complexity

NASA Technical Reports Server (NTRS)

Tian, Jianhui; Porter, Adam; Zelkowitz, Marvin V.

1992-01-01

Identification of high cost modules has been viewed as one mechanism to improve overall system reliability, since such modules tend to produce more than their share of problems. A decision tree model was used to identify such modules. In this current paper, a previously developed axiomatic model of program complexity is merged with the previously developed decision tree process for an improvement in the ability to identify such modules. This improvement was tested using data from the NASA Software Engineering Laboratory.

Can cost make a difference dosimetrically? Volumetric modulated arc therapy study for multileaf collimators of various widths for head and neck and prostate cancers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ho, Jong-Han, E-mail: jonghanho@gmail.com; Hagler, Shane; Lujano, Carrie

Cancer is a global health issue that disproportionately kills based on stage of disease, cellular pathology, and genetics, to name a few. Another variable to consider in this ongoing fight is treatment machine complexity that leads to elevated development and purchasing cost, leading to a reduced use. Reducing the complexity (in hopes of lowering costs) would benefit underdeveloped, low- and middle-income countries by introducing newer treatment technology, as their currently accepted standards do not meet standards of more advanced, developed countries. In this study, unilateral head and neck (H&N), and prostate cases using volumetric modulated arc therapy (VMAT) were testedmore » with multiple segment widths of 5, 10, 15, and 20 mm to create treatable plans. Pinnacle 9.10v was used for planning purposes. A total of 12 cases were planned with varying multileaf collimator (MLC) widths. Treatment plans were evaluated retrospectively. Results show that altering the MLC widths from 5 through 20 mm produces both comparable and treatable plans up to 99% and 98% target coverage for H&N and prostate, respectively, albeit clinically significant hot spots were shown to increase with increasing segment width. Furthermore, the results show that increasing widths can produce comparable treatment plans as measured against our current Food and Drug Administration (FDA)–approved treatment devices—leading to an increase in treatment efficacy in economically underdeveloped countries.« less

Investigation of test methods, material properties, and processes for solar cell encapsulants

NASA Technical Reports Server (NTRS)

1984-01-01

Photovoltaic (PV) modules consist of a string of electrically interconnected silicon solar cells capable of producing practical quantities of electrical power when exposed to sunlight. To insure high reliability and long term performance, the functional components of the solar cell module must be adequately protected from the environment by some encapsulation technique. The encapsulation system must provide mechanical support for the cells and corrosion protection for the electrical components. The goal of the program is to identify and develop encapsulation systems consistent with the PV module operating requirements of 30 year life and a target cost of $0.70 per peak watt ($70 per square meter) (1980 dollars). Assuming a module efficiency of ten percent, which is equivalent to a power output of 100 watts per square meter in midday sunlight, the capital cost of the modules may be calculated to be $70.00 per square meter. Out of this cost goal, only 20 percent is available for encapsulation due to the high cost of the cells, interconnects, and other related components. The encapsulation cost allocation may then be stated as $14.00 per square meter, included all coatings, pottant and mechanical supports for the cells.

System and method for design and optimization of grid connected photovoltaic power plant with multiple photovoltaic module technologies

DOEpatents

Thomas, Bex George; Elasser, Ahmed; Bollapragada, Srinivas; Galbraith, Anthony William; Agamy, Mohammed; Garifullin, Maxim Valeryevich

2016-03-29

A system and method of using one or more DC-DC/DC-AC converters and/or alternative devices allows strings of multiple module technologies to coexist within the same PV power plant. A computing (optimization) framework estimates the percentage allocation of PV power plant capacity to selected PV module technologies. The framework and its supporting components considers irradiation, temperature, spectral profiles, cost and other practical constraints to achieve the lowest levelized cost of electricity, maximum output and minimum system cost. The system and method can function using any device enabling distributed maximum power point tracking at the module, string or combiner level.

Investigation of test methods, material properties, and processes for solar cell encapsulants

NASA Technical Reports Server (NTRS)

Willis, P. B.

1983-01-01

A study of potentially useful low cost encapsulation materials for the Flat-Plate Solar Array project is discussed. The goal is to identify, evaluate, test and recommend encapsulant materials and processes for the production of cost-effective, long life solar cell modules. Technical investigations included studies of aging and degradation of candidate encapsulation materials, continued identification of primers for durable bonding of module interfaces, continued evaluation of soil resistant treatments for the sunlit surface of the module and testing of corrosion protective coatings for use low cost mild steel substrates.

Using adhesives as a means to reduce costs and increase performance in the production of photovoltaic electricity.

PubMed

Thorey, Claire

2013-01-01

Although adhesives have been used for many years to manufacture cars in more efficient ways, their potential has not yet been fully exploited by the renewable energy industry. We argue in this article that photovoltaic module manufacturers can save costs and differentiate from competition by careful selection and use of their bonding systems. Clever adhesives can enable new, more effective product designs and can play a major role in the longevity of the complete product.

Space station: Cost and benefits

NASA Technical Reports Server (NTRS)

1983-01-01

Costs for developing, producing, operating, and supporting the initial space station, a 4 to 8 man space station, and a 4 to 24 man space station are estimated and compared. These costs include contractor hardware; space station assembly and logistics flight costs; and payload support elements. Transportation system options examined include orbiter modules; standard and extended duration STS fights; reusable spacebased perigee kick motor OTV; and upper stages. Space station service charges assessed include crew hours; energy requirements; payload support module storage; pressurized port usage; and OTV service facility. Graphs show costs for science missions, space processing research, small communication satellites; large GEO transportation; OVT launch costs; DOD payload costs, and user costs.

Effects of design on cost of flat-plate solar photovoltaic arrays for terrestrial central station power applications

NASA Technical Reports Server (NTRS)

Tsou, P.; Stolte, W.

1978-01-01

The paper examines the impact of module and array designs on the balance-of-plant costs for flat-plate terrestrial central station power applications. Consideration is given to the following types of arrays: horizontal, tandem, augmented, tilt adjusted, and E-W tracking. The life-cycle cost of a 20-year plant life serves as the costing criteria for making design and cost tradeoffs. A tailored code of accounts is developed for determining consistent photovoltaic power plant costs and providing credible photovoltaic system cost baselines for flat-plate module and array designs by costing several varying array design approaches.

Study of curved glass photovoltaic module and module electrical isolation design requirements

NASA Technical Reports Server (NTRS)

1980-01-01

The design of a 1.2 by 2.4 m curved glass superstrate and support clip assembly is presented, along with the results of finite element computer analysis and a glass industry survey conducted to assess the technical and economic feasibility of the concept. Installed costs for four curved glass module array configurations are estimated and compared with cost previously reported for comparable flat glass module configurations. Electrical properties of candidate module encapsulation systems are evaluated along with present industry practice for the design and testing of electrical insulation systems. Electric design requirements for module encapsulation systems are also discussed.

Study of curved glass photovoltaic module and module electrical isolation design requirements

NASA Astrophysics Data System (ADS)

1980-06-01

The design of a 1.2 by 2.4 m curved glass superstrate and support clip assembly is presented, along with the results of finite element computer analysis and a glass industry survey conducted to assess the technical and economic feasibility of the concept. Installed costs for four curved glass module array configurations are estimated and compared with cost previously reported for comparable flat glass module configurations. Electrical properties of candidate module encapsulation systems are evaluated along with present industry practice for the design and testing of electrical insulation systems. Electric design requirements for module encapsulation systems are also discussed.

Low-power nanophotonics: material and device technology

NASA Astrophysics Data System (ADS)

Thylén, Lars; Holmstrom, Petter; Wosinski, Lech; Lourdudoss, Sebastian

2013-05-01

Development in photonics for communications and interconnects pose increasing requirements on reduction of footprint, power dissipation and cost, as well as increased bandwidth. Nanophotonics integrated photonics has been viewed as a solution to this, capitalizing on development in nanotechnology and an increased understanding of light matter interaction on the nanoscale. The latter can be exemplified by plasmonics and low dimensional semiconductors such as quantum dots (QDs). In this scenario the development of improved electrooptic materials is of great importance, the electrooptic polymers being an example, since they potentially offer superior properties for optical phase modulators in terms of power and integratability. Phase modulators are essential for e.g. the rapidly developing advanced modulation formats, since phase modulation basically can generate any type of modulation. The electrooptic polymers, in combination with plasmonics nanoparticle array waveguides or nanostructured hybrid plasmonic media can give extremely compact and low power dissipation modulators. Low-dimensional semiconductors, e.g. in the shape of QDs, can be employed for modulation or switching functions, offering possibilities for scaling to 2 or 3 dimensions for advanced switching functions. In both the high field confinement plasmonics and QDs, the nanosizing is due to nearfield interactions, albeit being of different physical origin in the two cases. Epitaxial integration of III-V structures on Si plays an important role in developing high-performance light sources on silicon, eventually integrated with silicon electronics. A brief remark on all-optical vs. electronically controlled optical switching systems is also given.

Lifecycle Cost Analysis of Green Infrastructure. U.S. EPA National Stormwater Calculator: Low Impact Development Stormwater Control Cost Estimation Module & Future Enhancements

EPA Science Inventory

This presentation will cover the new cost estimation module of the US EPA National Stormwater Calculator and future enhancements, including a new mobile web app version of the tool. The presentation mainly focuses on how the calculator may be used to provide planning level capita...

Characterization of a low concentrator photovoltaics module

NASA Astrophysics Data System (ADS)

Butler, B. A.; van Dyk, E. E.; Vorster, F. J.; Okullo, W.; Munji, M. K.; Booysen, P.

2012-05-01

Low concentration photovoltaic (LCPV) systems have the potential to reduce the cost per kWh of electricity compared to conventional flat-plate photovoltaics (PV) by up to 50%. The cost-savings are realised by replacing expensive PV cells with relatively cheaper optical components to concentrate incident solar irradiance onto a receiver and by tracking the sun along either 1 axis or 2 axes. A LCPV module consists of three interrelated subsystems, viz., the optical, electrical and the thermal subsystems, which must be considered for optimal module design and performance. Successful integration of these subsystems requires the balancing of cost, performance and reliability. In this study LCPV experimental prototype modules were designed, built and evaluated with respect to optimisation of the three subsystems and overall performance. This paper reports on the optical and electrical evaluation of a prototype LCPV module.

Energy cost and putative benefits of cellular mechanisms modulating buoyancy in aflagellate marine phytoplankton.

PubMed

Lavoie, Michel; Raven, John A; Levasseur, Maurice

2016-04-01

Little information is available on the energetics of buoyancy modulation in aflagellate phytoplankton, which comprises the majority of autotrophic cells found in the ocean. Here, we computed for three aflagellate species of marine phytoplankton (Emiliania huxleyi, Thalassiosira pseudonana, and Ethmodiscus rex) the theoretical minimum energy cost as photons absorbed and nitrogen resource required of the key physiological mechanisms (i.e., replacement of quaternary ammonium by dimethyl-sulfoniopropionate, storage of polysaccharides, and cell wall biosynthesis) affecting the cell's vertical movement as a function of nitrogen (N) availability. These energy costs were also normalized to the capacity of each buoyancy mechanism to modulate sinking or rising rates based on Stokes' law. The three physiological mechanisms could act as ballast in the three species tested in conditions of low N availability at a low fraction (<12%) of the total photon energy cost for growth. Cell wall formation in E. huxleyi was the least costly ballast strategy, whereas in T. pseudonana, the photon energy cost of the three ballast strategies was similar. In E. rex, carbohydrate storage and mobilization appear to be energetically cheaper than modulations in organic solute synthesis to achieve vertical migration. This supports the carbohydrate-ballast strategy for vertical migration for this species, but argues against the theory of replacement of low- or high-density organic solutes. This study brings new insights into the energy cost and potential selective advantages of several strategies modulating the buoyancy of aflagellate marine phytoplankton. © 2016 Phycological Society of America.

A computerized education module improves patient knowledge and attitudes about appropriate antibiotic use for acute respiratory tract infections.

PubMed

Price, Erika Leemann; Mackenzie, Thomas D; Metlay, Joshua P; Camargo, Carlos A; Gonzales, Ralph

2011-12-01

Over-use of antibiotics for acute respiratory infections (ARIs) increases antimicrobial resistance, treatment costs, and side effects. Patient desire for antibiotics contributes to over-use. To explore whether a point-of-care interactive computerized education module increases patient knowledge and decreases desire for antibiotics. Bilingual (English/Spanish) interactive kiosks were available in 8 emergency departments as part of a multidimensional intervention to reduce antibiotic prescribing for ARIs. The symptom-tailored module included assessment of symptoms, knowledge about ARIs (3 items), and desire for antibiotics on a 10-point visual analog scale. Multivariable analysis assessed predictors of change in desire for antibiotics. Of 686 adults with ARI symptoms, 63% initially thought antibiotics might help. The proportion of patients with low (1-3 on the scale) desire for antibiotics increased from 22% pre-module to 49% post-module (p<.001). Self-report of "learning something new" was associated with decreased desire for antibiotics, after adjusting for baseline characteristics (p=.001). An interactive educational kiosk improved knowledge about antibiotics and ARIs. Learning correlated with changes in personal desire for antibiotics. By reducing desire for antibiotics, point-of-care interactive educational computer technology may help decrease inappropriate use for antibiotics for ARIs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A Study of the Economic Benefit Potential of Intermodal Transports

NASA Technical Reports Server (NTRS)

Nelson, J. M.; Kawai, R. T.; Gregg, R. D.; McKinley, Robert E., Jr. (Technical Monitor)

2001-01-01

A conceptual study was conducted to determine the benefit potential of an Intermodal Transport in which quick change payload modules are used to reduce the cost of air travel by increasing daily utilization. Three basic concepts varying the degree of modularity were investigated for a 122,000 pounds payload 3,000 NM range regional wide body transport. The profit potential for operating as a passenger transport during the day and as a freighter at night was assessed. Assuming current levels of profitability, Intermodal operations could offer an operating cost reduction potential up to 20%. Enabling technology needs are identified as very quiet aircraft for expanded night operations, distributed load carrying quick disconnect latching, and configuration dependent safety issues. Recommendations are made to explore if additional benefits are possible from alternative mission and usage modules.

Reactive control processes contributing to residual switch cost and mixing cost across the adult lifespan.

PubMed

Whitson, Lisa R; Karayanidis, Frini; Fulham, Ross; Provost, Alexander; Michie, Patricia T; Heathcote, Andrew; Hsieh, Shulan

2014-01-01

In task-switching paradigms, performance is better when repeating the same task than when alternating between tasks (switch cost) and when repeating a task alone rather than intermixed with another task (mixing cost). These costs remain even after extensive practice and when task cues enable advanced preparation (residual costs). Moreover, residual reaction time mixing cost has been consistently shown to increase with age. Residual switch and mixing costs modulate the amplitude of the stimulus-locked P3b. This mixing effect is disproportionately larger in older adults who also prepare more for and respond more cautiously on these "mixed" repeat trials (Karayanidis et al., 2011). In this paper, we analyze stimulus-locked and response-locked P3 and lateralized readiness potentials to identify whether residual switch and mixing cost arise from the need to control interference at the level of stimulus processing or response processing. Residual mixing cost was associated with control of stimulus-level interference, whereas residual switch cost was also associated with a delay in response selection. In older adults, the disproportionate increase in mixing cost was associated with greater interference at the level of decision-response mapping and response programming for repeat trials in mixed-task blocks. These findings suggest that older adults strategically recruit greater proactive and reactive control to overcome increased susceptibility to post-stimulus interference. This interpretation is consistent with recruitment of compensatory strategies to compensate for reduced repetition benefit rather than an overall decline on cognitive flexibility.

Reactive control processes contributing to residual switch cost and mixing cost across the adult lifespan

PubMed Central

Whitson, Lisa R.; Karayanidis, Frini; Fulham, Ross; Provost, Alexander; Michie, Patricia T.; Heathcote, Andrew; Hsieh, Shulan

2014-01-01

In task-switching paradigms, performance is better when repeating the same task than when alternating between tasks (switch cost) and when repeating a task alone rather than intermixed with another task (mixing cost). These costs remain even after extensive practice and when task cues enable advanced preparation (residual costs). Moreover, residual reaction time mixing cost has been consistently shown to increase with age. Residual switch and mixing costs modulate the amplitude of the stimulus-locked P3b. This mixing effect is disproportionately larger in older adults who also prepare more for and respond more cautiously on these “mixed” repeat trials (Karayanidis et al., 2011). In this paper, we analyze stimulus-locked and response-locked P3 and lateralized readiness potentials to identify whether residual switch and mixing cost arise from the need to control interference at the level of stimulus processing or response processing. Residual mixing cost was associated with control of stimulus-level interference, whereas residual switch cost was also associated with a delay in response selection. In older adults, the disproportionate increase in mixing cost was associated with greater interference at the level of decision-response mapping and response programming for repeat trials in mixed-task blocks. These findings suggest that older adults strategically recruit greater proactive and reactive control to overcome increased susceptibility to post-stimulus interference. This interpretation is consistent with recruitment of compensatory strategies to compensate for reduced repetition benefit rather than an overall decline on cognitive flexibility. PMID:24817859

Forage Harvest and Transport Costs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, J.; Downing, M.; Turhollow, A.

An engineering-economic approach is used to calculate harvest, in-field transport, and over-the-road transport costs for hay as bales and modules, silage, and crop residues as bales and modules. Costs included are equipment depreciation interest; fuel, lube, and oil; repairs; insurance, housing, and taxes; and labor. Field preparation, pest control, fertilizer, land, and overhead are excluded from the costs calculated Equipment is constrained by power available, throughput or carrying capacity, and field speed.

Implications for current regulatory waste toxicity characterisation methods from analysing metal and metalloid leaching from photovoltaic modules

NASA Astrophysics Data System (ADS)

Collins, Mary Kayla; Anctil, Annick

2017-07-01

The appropriateness of regulatory methods to characterise the toxicity of photovoltaic (PV) modules was investigated to quantify potential environmental impacts for modules disposed of in landfills. Because solar energy is perceived as a green technology, it is important to ensure that end-of-life issues will not be detrimental to solar energy's success. United States Environmental Protection Agency Method 1311, California waste extraction test, and modified versions of both were performed on a multi-crystalline silicon module and cells and a copper indium gallium diselenide (CIGS) module. Variations in metal leachate concentrations were found with changes in testing parameters. Lead concentrations from the multi-crystalline module ranged from 16.2 to 50.2 mg/L. Cadmium concentrations from the CIGS module ranged from 0.1 to 3.52 mg/L. This raises doubt that regulatory methods can adequately characterise PV modules. The results are useful for developing end-of-life procedures, which is a positive step towards avoiding an e-waste problem and continuing trends of increasing installation and cost reduction in the PV market.

Organizing Space Shuttle parametric data for maintainability

NASA Technical Reports Server (NTRS)

Angier, R. C.

1983-01-01

A model of organization and management of Space Shuttle data is proposed. Shuttle avionics software is parametrically altered by a reconfiguration process for each flight. As the flight rate approaches an operational level, current methods of data management would become increasingly complex. An alternative method is introduced, using modularized standard data, and its implications for data collection, integration, validation, and reconfiguration processes are explored. Information modules are cataloged for later use, and may be combined in several levels for maintenance. For each flight, information modules can then be selected from the catalog at a high level. These concepts take advantage of the reusability of Space Shuttle information to reduce the cost of reconfiguration as flight experience increases.

Trial type probability modulates the cost of antisaccades

PubMed Central

Chiau, Hui-Yan; Tseng, Philip; Su, Jia-Han; Tzeng, Ovid J. L.; Hung, Daisy L.; Muggleton, Neil G.

2011-01-01

The antisaccade task, where eye movements are made away from a target, has been used to investigate the flexibility of cognitive control of behavior. Antisaccades usually have longer saccade latencies than prosaccades, the so-called antisaccade cost. Recent studies have shown that this antisaccade cost can be modulated by event probability. This may mean that the antisaccade cost can be reduced, or even reversed, if the probability of surrounding events favors the execution of antisaccades. The probabilities of prosaccades and antisaccades were systematically manipulated by changing the proportion of a certain type of trial in an interleaved pro/antisaccades task. We aimed to disentangle the intertwined relationship between trial type probabilities and the antisaccade cost with the ultimate goal of elucidating how probabilities of trial types modulate human flexible behaviors, as well as the characteristics of such modulation effects. To this end, we examined whether implicit trial type probability can influence saccade latencies and also manipulated the difficulty of cue discriminability to see how effects of trial type probability would change when the demand on visual perceptual analysis was high or low. A mixed-effects model was applied to the analysis to dissect the factors contributing to the modulation effects of trial type probabilities. Our results suggest that the trial type probability is one robust determinant of antisaccade cost. These findings highlight the importance of implicit probability in the flexibility of cognitive control of behavior. PMID:21543748

Flexible organic tandem solar modules: a story of up-scaling

NASA Astrophysics Data System (ADS)

Spyropoulos, George D.; Kubis, Peter; Li, Ning; Lucera, Luca; Salvador, Michael; Baran, Derya; Machui, Florian; Ameri, Tayebeh; Voigt, Monika M.; Brabec, Christoph J.

2014-10-01

The competition in the field of solar energy between Organic Photovoltaics (OPVs) and several Inorganic Photovoltaic technologies is continuously increasing to reach the ultimate purpose of energy supply from inexpensive and easily manufactured solar cell units. Solution-processed printing techniques on flexible substrates attach a tremendous opportunity to the OPVs for the accomplishment of low-cost and large area applications. Furthermore, tandem architectures came to boost up even more OPVs by increasing the photon-harvesting properties of the device. In this work, we demonstrate the road of realizing flexible organic tandem solar modules constructed by a fully roll-to-roll compatible processing. The modules exhibit an efficiency of 5.4% with geometrical fill factors beyond 80% and minimized interconnection-resistance losses. The processing involves low temperature (<70 °C), coating methods compatible with slot die coating and high speed and precision laser patterning.

Optimisation of a low cost SLM for diffraction efficiency and ghost order suppression

NASA Astrophysics Data System (ADS)

Bowman, R.; D'Ambrosio, V.; Rubino, E.; Jedrkiewicz, O.; di Trapani, P.; Padgett, M. J.

2011-11-01

Spatial Light Modulators (SLMs) are a powerful tool in many optics laboratories, but due to the technology required for their fabrication, they are usually very expensive. Recently some inexpensive devices have been produced, however their phase shift range is less than 2π, leading to a loss of diffraction efficiency for the SLM. We show how to improve the first order diffraction efficiency of such an SLM by adjusting the blazing function, and obtain a 1.5 times increase in first order diffracted power. Even a perfect SLM with 2π phase throw can produce undesired effects in some situations; for example in holographic optical tweezers it is common to find unwanted "ghost spots" near to the array of first-order spots. Modulating the amplitude, by spatially modulating the blazing function, allows us to suppress the ghost spots. This increases the contrast between desired and unwanted spots by more than an order of magnitude.

A Low Cost Single Chip VDL Compatible Transceiver ASIC

NASA Technical Reports Server (NTRS)

Becker, Robert

2004-01-01

Recent trends in commercial communications system components have focussed almost exclusively on cellular telephone technology. As many of the traditional sources of receiver components have discontinued non-cellular telephone products, the designers of avionics and other low volume radio applications find themselves increasingly unable to find highly integrated components. This is particularly true for low power, low cost applications which cannot afford the lavish current consumption of the software defined radio approach increasingly taken by certified device manufacturers. In this paper, we describe a low power transceiver chip targeting applications from low VHF to low UHF frequencies typical of avionics systems. The chip encompasses a selectable single or double conversion design for the receiver and a low power IF upconversion transmitter. All local oscillators are synthesized and integrated into the chip. An on-chip I-Q modulator and demodulator provide baseband modulation and demodulation capability allowing the use of low power, fixed point signal processing components for signal demodulation. The goal of this program is to demonstrate a low cost VDL mode-3 transceiver using this chip to receive text weather information sent using 4-slot TDMA with no support for voice. The data will be sent from an experimental ground station. This work is funded by NASA Glenn Research Center.

Effects of dust accumulation and module cleaning on performance ratio of solar rooftop system and solar power plants

NASA Astrophysics Data System (ADS)

Sakarapunthip, Nattakarn; Chenvidhya, Dhirayut; Chuangchote, Surawut; Kirtikara, Krissanapong; Chenvidhya, Tanokkorn; Onreabroy, Wandee

2017-08-01

Thailand is an agricultural country, with rice, sugar, and cassava as the major export products. Production of rice, sugar cane, and cassava entails agricultural activities that give rise to significant airborne dusts. In this work, five photovoltaic (PV) units (one solar rooftop and four power plants) are selected for the study. From the study of dust accumulation on glass surface located near rice farms, it was found that opaque areas due to the deposition of dust are 11-14% after 1-2-week exposure. As a consequence, PV system performance is affected. Performance ratio was calculated to determine these effects. Overall results reveal that during the dry and hot seasons, dust deposition significantly affects the performance ratio. The performance ratio reduces by 1.6-3% for 1-month dust accumulation and reduces by 6-8% for 2-month dust accumulation. After cleaning the dust accumulated, the performance ratio greatly increases, resulting in the increase in the energy output by 10%. This increase provides economic and cost benefits of PV cleaning. The performance ratio is not significantly changed during the rainy season, which PV modules are relatively clean as the dust is washed away by rain. It was also found that most of the solar power plants in Thailand still rely on manual cleaning of PV modules with washing water followed by wiping. However, only one power plant, employs a machine for cleaning, resulting in lower cleaning costs.

Genetic Algorithm Optimization of a Cost Competitive Hybrid Rocket Booster

NASA Technical Reports Server (NTRS)

Story, George

2015-01-01

Performance, reliability and cost have always been drivers in the rocket business. Hybrid rockets have been late entries into the launch business due to substantial early development work on liquid rockets and solid rockets. Slowly the technology readiness level of hybrids has been increasing due to various large scale testing and flight tests of hybrid rockets. One remaining issue is the cost of hybrids versus the existing launch propulsion systems. This paper will review the known state-of-the-art hybrid development work to date and incorporate it into a genetic algorithm to optimize the configuration based on various parameters. A cost module will be incorporated to the code based on the weights of the components. The design will be optimized on meeting the performance requirements at the lowest cost.

Genetic Algorithm Optimization of a Cost Competitive Hybrid Rocket Booster

NASA Technical Reports Server (NTRS)

Story, George

2014-01-01

Performance, reliability and cost have always been drivers in the rocket business. Hybrid rockets have been late entries into the launch business due to substantial early development work on liquid rockets and later on solid rockets. Slowly the technology readiness level of hybrids has been increasing due to various large scale testing and flight tests of hybrid rockets. A remaining issue is the cost of hybrids vs the existing launch propulsion systems. This paper will review the known state of the art hybrid development work to date and incorporate it into a genetic algorithm to optimize the configuration based on various parameters. A cost module will be incorporated to the code based on the weights of the components. The design will be optimized on meeting the performance requirements at the lowest cost.

Study of Multimission Modular Spacecraft (MMS) propulsion requirements

NASA Technical Reports Server (NTRS)

Fischer, N. H.; Tischer, A. E.

1977-01-01

The cost effectiveness of various propulsion technologies for shuttle-launched multimission modular spacecraft (MMS) missions was determined with special attention to the potential role of ion propulsion. The primary criterion chosen for comparison for the different types of propulsion technologies was the total propulsion related cost, including the Shuttle charges, propulsion module costs, upper stage costs, and propulsion module development. In addition to the cost comparison, other criteria such as reliability, risk, and STS compatibility are examined. Topics covered include MMS mission models, propulsion technology definition, trajectory/performance analysis, cost assessment, program evaluation, sensitivity analysis, and conclusions and recommendations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yelundur, Vijay

Suniva, Inc., in collaboration with the University Center for Excellence in Photovoltaics (UCEP) at the Georgia Institute of Technology (GIT) proposed this comprehensive three year program to enable the development of an advanced high performance product that will help the US regain its competitive edge in PV. This project was designed to overcome cost and efficiency barriers through advances in PV science, technology innovation, low-cost manufacturing and full production of ~22.5% efficient n-type Si cells in Norcross, GA. At the heart of the project is the desire to complement the technology being developed concurrently under the Solarmat and ARPAe initiativesmore » to develop a differentiated product superior in both performance and cost effectiveness to the competing alternatives available on the market, and push towards achieving SunShot objectives while ensuring a sustainable business model based on US manufacturing. A significant reduction of the costs in modules produced today will need to combine reductions in wafer costs, cell processing costs as well as module fabrication costs while delivering a product that is not only more efficient under test conditions but also increases the energy yield in outdoor operations. This project will result in a differentiated high performance product and technology that is consistent with sustaining PV manufacturing in the US for a longer term and further highlights the need for continued support for developing the next generation concepts that can keep US manufacturing thriving to support the growing demand for PV in the US and consistent with the US government’s mandates for energy independence.« less

A preliminary 'test case' manufacturing sequence for 50 cents/watt solar photovoltaic modules in 1986

NASA Technical Reports Server (NTRS)

Bickler, D. B.

1979-01-01

The paper describes a 'test case' manufacturing process sequence for solar photovoltaic modules which will cost 50 cents/watt in 1986. The process, which starts with the purification of silicon grown into 75-mm-wide thin ribbons, is discussed, and the plant layout is depicted; each department is sized to produce 250 MW of modules/per year. The cost of this process sequence is compared to present technology at various companies showing considerable spread for each process; data are tabulated in a composite state-of-the-art cell processing cost summary for these processes.

Active optimal control strategies for increasing the efficiency of photovoltaic cells

NASA Astrophysics Data System (ADS)

Aljoaba, Sharif Zidan Ahmad

Energy consumption has increased drastically during the last century. Currently, the worldwide energy consumption is about 17.4 TW and is predicted to reach 25 TW by 2035. Solar energy has emerged as one of the potential renewable energy sources. Since its first physical recognition in 1887 by Adams and Day till nowadays, research in solar energy is continuously developing. This has lead to many achievements and milestones that introduced it as one of the most reliable and sustainable energy sources. Recently, the International Energy Agency declared that solar energy is predicted to be one of the major electricity production energy sources by 2035. Enhancing the efficiency and lifecycle of photovoltaic (PV) modules leads to significant cost reduction. Reducing the temperature of the PV module improves its efficiency and enhances its lifecycle. To better understand the PV module performance, it is important to study the interaction between the output power and the temperature. A model that is capable of predicting the PV module temperature and its effects on the output power considering the individual contribution of the solar spectrum wavelengths significantly advances the PV module edsigns toward higher efficiency. In this work, a thermoelectrical model is developed to predict the effects of the solar spectrum wavelengths on the PV module performance. The model is characterized and validated under real meteorological conditions where experimental temperature and output power of the PV module measurements are shown to agree with the predicted results. The model is used to validate the concept of active optical filtering. Since this model is wavelength-based, it is used to design an active optical filter for PV applications. Applying this filter to the PV module is expected to increase the output power of the module by filtering the spectrum wavelengths. The active filter performance is optimized, where different cutoff wavelengths are used to maximize the module output power. It is predicted that if the optimized active optical filter is applied to the PV module, the module efficiency is predicted to increase by about 1%. Different technologies are considered for physical implementation of the active optical filter.

SOLVENT NANOFILTRATION USING LOW-COST INORGANIC MEMBRANE MODULES - PHASE I

EPA Science Inventory

This Phase I project addresses: (1) development of fully inorganic nanofiltration (NF) membrane modules that have the attributes of low-cost, excellent chemical resistance in aggressive organic and aqueous media and high thermal stability; and (2) demonstration of the perfo...

Low cost high efficiency GaAs monolithic RF module for SARSAT distress beacons

NASA Technical Reports Server (NTRS)

Petersen, W. C.; Siu, D. P.; Cook, H. F.

1991-01-01

Low cost high performance (5 Watts output) 406 MHz beacons are urgently needed to realize the maximum utilization of the Search and Rescue Satellite-Aided Tracking (SARSAT) system spearheaded in the U.S. by NASA. Although current technology can produce beacons meeting the output power requirement, power consumption is high due to the low efficiency of available transmitters. Field performance is currently unsatisfactory due to the lack of safe and reliable high density batteries capable of operation at -40 C. Low cost production is also a crucial but elusive requirement for the ultimate wide scale utilization of this system. Microwave Monolithics Incorporated (MMInc.) has proposed to make both the technical and cost goals for the SARSAT beacon attainable by developing a monolithic GaAs chip set for the RF module. This chip set consists of a high efficiency power amplifier and a bi-phase modulator. In addition to implementing the RF module in Monolithic Microwave Integrated Circuit (MMIC) form to minimize ultimate production costs, the power amplifier has a power-added efficiency nearly twice that attained with current commercial technology. A distress beacon built using this RF module chip set will be significantly smaller in size and lighter in weight due to a smaller battery requirement, since the 406 MHz signal source and the digital controller have far lower power consumption compared to the 5 watt power amplifier. All the program tasks have been successfully completed. The GaAs MMIC RF module chip set has been designed to be compatible with the present 406 MHz signal source and digital controller. A complete high performance low cost SARSAT beacon can be realized with only additional minor iteration and systems integration.

Ultra-Low-Noise W-Band MMIC Detector Modules

NASA Technical Reports Server (NTRS)

Gaier, Todd C.; Samoska, Lorene A.; Kangaslahti, Pekka P.; Van Vinkle, Dan; Tantawi, Sami; Fox, John; Church, Sarah E.; Lau, Jusy M.; Sieth, Matthew M.; Voll, Patricia E.;

Phase Two of the Array Automated Assembly Task for the Low Cost Solar Array Project

NASA Technical Reports Server (NTRS)

Campbell, R. B.; Page, D. J.; Rai-Choudhury, P.; Seman, E. J.; Hanes, M. H.; Rohatgi, A.; Davis, J. R.

1979-01-01

Various top contact metal systems were studied. Only Ti Pd Cu approaches baseline (Ti Pd Ag) quality, but this system shows a lack of long term stability. Aluminum back surface field structures were fabricated and thicknesses of p superscript + material of up to 7.0 microns were achieved with open circuit voltages of 0.59V. A general purpose ultrasonic welder was purchased and tests using various metal foils are under way. During fabrication of the demonstration module, several cells became cracked. Due to redundancy of interconnections, the module was not open circuited but the efficiency was reduced to 8.8%. The broken cell was interconnected with a strap across the back and the efficiency was increased to 11.5%. A cost analysis was made and the results indicate a selling price of $0.56/watt peak (in 1986 with 1975 dollars).

Using Gamification to Improve Productivity and Increase Knowledge Retention During Orientation.

PubMed

Brull, Stacey; Finlayson, Susan; Kostelec, Teresa; MacDonald, Ryan; Krenzischeck, Dina

2017-09-01

Nursing administrators must provide cost-effective and efficient ways of orientation training. Traditional methods including classroom lecture can be costly with low retention of the information. Gamification engages the user, provides a level of enjoyment, and uses critical thinking skills. The aim of this study is to explore the effectiveness, during orientation, of 3 different teaching methods: didactic, online modules, and gamification. Specifically, is there a difference in nurses' clinical knowledge postorientation using these learning approaches? A quasi-experimental study design with a 115-person convenience sample split nurses into 3 groups for evaluation of clinical knowledge before and after orientation. The gamification orientation group had the highest mean scores postorientation compared with the didactic and online module groups. Findings demonstrate gamification as an effective way to teach when compared with more traditional methods. Staff enjoy this type of learning and retained more knowledge when using gaming elements.

Low cost and high performance GPON, GEPON and RFoG optical network pentaplexer module design using diffractive grating approach

NASA Astrophysics Data System (ADS)

Chen, I.-Ju; Chi, Chang-Chia; Tarn, Chen-Wen

2016-01-01

A new architecture of a pentaplexer transceiver module which can be used in GPON/GEPON and RFoG triple play optical networks with supporting of the multiple optical wavelengths of 1310 nm, 1490 nm, 1550 nm, 1610 nm, and 1650 nm, is proposed. By using diffractive grating elements combing with market readily available GRIN (Gradient-Index) lens, grating, mirrors, beamsplitter, LDs (Laser Diodes), and PDs (Photodetectors), the proposed design have the advantages of low cost, high efficiency/performance, easy design and manufacturing, over the contemporary triplex transceivers which are made of multilayer filters or waveguides that increase the complexity of manufacturing and reduce the performance efficiency. With the proposed design, a pentaplexer system can accommodate GPON/GEPON, RFoG, and monitoring integration services, total five optical wavelength channels into a hybrid-integrated TO-CAN package platform with sufficient efficiency.

Thin-film filament-based solar cells and modules

NASA Astrophysics Data System (ADS)

Tuttle, J. R.; Cole, E. D.; Berens, T. A.; Alleman, J.; Keane, J.

1997-04-01

This concept paper describes a patented, novel photovoltaic (PV) technology that is capable of achieving near-term commercialization and profitability based upon design features that maximize product performance while minimizing initial and future manufacturing costs. DayStar Technologies plans to exploit these features and introduce a product to the market based upon these differential positions. The technology combines the demonstrated performance and reliability of existing thin-film PV product with a cell and module geometry that cuts material usage by a factor of 5, and enhances performance and manufacturability relative to standard flat-plate designs. The target product introduction price is 1.50/Watt-peak (Wp). This is approximately one-half the cost of the presently available PV product. Additional features include: increased efficiency through low-level concentration, no scribe or grid loss, simple series interconnect, high voltage, light weight, high-throughput manufacturing, large area immediate demonstration, flexibility, modularity.

Cost-effective FITL technologies for small business and residential customers

NASA Astrophysics Data System (ADS)

Andersen, Niels E.; Woolnough, Peter; Seidenberg, Juergen; Ferreira, Mario F. S.

1995-02-01

FIRST is a RACE project where 5 main European telecoms operators, 4 equipment manufacturers and one university have joined up to define and test in a field trial in Portugal a cost effective Optical Access Network. The main design target has been a system which gives cost effective provision of wideband services for small and medium business customers. The system however, incorporates provision of telephone, ISDN and analog and digital video for residential customers as well. Technologies have been chosen with the objective of providing a simple, robust and flexible system where initial deployment costs are low and closely related to the service take up. The paper describes the main technical features of the system and network applications which shows how the system may be introduced in network planning. The system is based on Passive Optical Network technology where video is distributed in the 1550 nm window and telecoms services transmitted at 1300 nm in full duplex mode. The telecoms system provides high capacity, flexibility in loop length and robustness towards outside plant performance. The Subcarrier Multiple Access (SCMA) method is used for upstream transmission of bi-directional telecoms services. SCMA has advantages compared to the Time Division Multiple Access technology used in other systems. Bandwidth/cost tradeoff is better and the lower requirements to the outside plant increases the overall cost benefit. Optical beat noise due to overlapping of laser spectra which may be a problem for this technology has been addressed with success through the use of a suitable modulation and control technique. This technology is further validated in the field trial. The video system provides cost effective long distance transmission on standard fiber with externally modulated lasers and cascaded amplifiers. Coexistence of analog and digital video on one fiber with different modulation schemes i.e. BPSK, QPSK and 64 QAM have been validated. Total life cycle cost evaluations based on availability data, maintenance requirements and expectations for service development have been made. The field trial will be running for two years.

Transcranial current stimulation focality using disc and ring electrode configurations: FEM analysis

NASA Astrophysics Data System (ADS)

Datta, Abhishek; Elwassif, Maged; Battaglia, Fortunato; Bikson, Marom

2008-06-01

We calculated the electric fields induced in the brain during transcranial current stimulation (TCS) using a finite-element concentric spheres human head model. A range of disc electrode configurations were simulated: (1) distant-bipolar; (2) adjacent-bipolar; (3) tripolar; and three ring designs, (4) belt, (5) concentric ring, and (6) double concentric ring. We compared the focality of each configuration targeting cortical structures oriented normal to the surface ('surface-radial' and 'cross-section radial'), cortical structures oriented along the brain surface ('surface-tangential' and 'cross-section tangential') and non-oriented cortical surface structures ('surface-magnitude' and 'cross-section magnitude'). For surface-radial fields, we further considered the 'polarity' of modulation (e.g. superficial cortical neuron soma hyper/depolarizing). The distant-bipolar configuration, which is comparable with commonly used TCS protocols, resulted in diffuse (un-focal) modulation with bi-directional radial modulation under each electrode and tangential modulation between electrodes. Increasing the proximity of the two electrodes (adjacent-bipolar electrode configuration) increased focality, at the cost of more surface current. At similar electrode distances, the tripolar-electrodes configuration produced comparable peak focality, but reduced radial bi-directionality. The concentric-ring configuration resulted in the highest spatial focality and uni-directional radial modulation, at the expense of increased total surface current. Changing ring dimensions, or use of two concentric rings, allow titration of this balance. The concentric-ring design may thus provide an optimized configuration for targeted modulation of superficial cortical neurons.

Automated array assembly task, phase 1

NASA Technical Reports Server (NTRS)

Carbajal, B. G.

1977-01-01

An assessment of state-of-the-art technologies that are applicable to silicon solar cell and solar cell module fabrication is provided. The assessment consists of a technical feasibility evaluation and a cost projection for high-volume production of silicon solar cell modules. The cost projection was approached from two directions; a design-to-cost analysis assigned cost goals to each major process element in the fabrication scheme, and a cost analysis built up projected costs for alternate technologies for each process element. A technical evaluation was used in combination with the cost analysis to identify a baseline low cost process. A novel approach to metal pattern design based on minimum power loss was developed. These design equations were used as a tool in the evaluation of metallization technologies.

Flat-plate solar array project. Volume 7: Module encapsulation

NASA Astrophysics Data System (ADS)

Cuddihy, E.; Coulbert, C.; Gupta, A.; Liang, R.

1986-10-01

The objective of the Encapsulation Task was to develop, demonstrate, and qualify photovoltaic (PV) module encapsulation systems that would provide 20 year (later decreased to 30 year) life expectancies in terrestrial environments, and which would be compatible with the cost and performance goals of the Flat-Plate Solar Array (FSA) Project. The scope of the Encapsulation Task included the identification, development, and evaluation of material systems and configurations required to support and protect the optically and electrically active solar cell circuit components in the PV module operating environment. Encapsulation material technologies summarized include the development of low cost ultraviolet protection techniques, stable low cost pottants, soiling resistant coatings, electrical isolation criteria, processes for optimum interface bonding, and analytical and experimental tools for evaluating the long term durability and structural adequacy of encapsulated modules. Field testing, accelerated stress testing, and design studies have demonstrated that encapsulation materials, processes, and configurations are available that meet the FSA cost and performance goals.

Flat-plate solar array project. Volume 7: Module encapsulation

NASA Technical Reports Server (NTRS)

Cuddihy, E.; Coulbert, C.; Gupta, A.; Liang, R.

1986-01-01

The objective of the Encapsulation Task was to develop, demonstrate, and qualify photovoltaic (PV) module encapsulation systems that would provide 20 year (later decreased to 30 year) life expectancies in terrestrial environments, and which would be compatible with the cost and performance goals of the Flat-Plate Solar Array (FSA) Project. The scope of the Encapsulation Task included the identification, development, and evaluation of material systems and configurations required to support and protect the optically and electrically active solar cell circuit components in the PV module operating environment. Encapsulation material technologies summarized include the development of low cost ultraviolet protection techniques, stable low cost pottants, soiling resistant coatings, electrical isolation criteria, processes for optimum interface bonding, and analytical and experimental tools for evaluating the long term durability and structural adequacy of encapsulated modules. Field testing, accelerated stress testing, and design studies have demonstrated that encapsulation materials, processes, and configurations are available that meet the FSA cost and performance goals.

Spacecraft expected cost analysis with k-out-of-n:G subsystems

NASA Technical Reports Server (NTRS)

Patterson, Richard; Suich, Ron

1991-01-01

In designing a subsystem for a spacecraft, the design engineer is often faced with a number of options ranging from planning an inexpensive subsystem with low reliability to selecting a highly reliable system that would cost much more. We minimize the total of the cost of the subsytem and the costs that would occur if the subsystem fails. We choose the subsystem with the lowest total. A k-out-of-n:G subsystem has n modules, of which k are required to be good for the subsystem to be good. We examine two models to illustrate the principles of the k-out-of-n:G subsystem designs. For the first model, the following assumptions are necessary: the probability of failure of any module in the system is not affected by the failure of any other module; and each of the modules has the same probabillity of success. For the second model we are also free to choose k in our subsystem.

Solar photovoltaic power stations

NASA Technical Reports Server (NTRS)

Chowaniec, C. R.; Pittman, P. F.; Ferber, R. R.; Marshall, B. W.

1977-01-01

The subsystems of a solar photovoltaic central power system are identified and the cost of major components are estimated. The central power system, which would have a peak power capability in the range of 50 to 1000 MW, utilizes two types of subsystems - a power conditioner and a solar array. Despite differences in costs of inverters, the overall cost of the total power conditioning subsystem is about the same for all approaches considered. A combination of two inverters operating from balanced dc buses as a pair of 6-pulse groups is recommended. A number of different solar cell modules and tracking array structures were analyzed. It is concluded that when solar cell costs are high (greater than $500/kW), high concentration modules are more cost effective than those with low concentration. Vertical-axis tracking is the most effective of the studied tracking modes. For less expensive solar cells (less than $400/kW), fixed tilt collector/reflector modules are more cost effective than those which track.

A high capacity data centre network: simultaneous 4-PAM data at 20 Gbps and 2 GHz phase modulated RF clock signal over a single VCSEL carrier

NASA Astrophysics Data System (ADS)

Isoe, G. M.; Wassin, S.; Gamatham, R. R. G.; Leitch, A. W. R.; Gibbon, T. B.

2017-11-01

Optical fibre communication technologies are playing important roles in data centre networks (DCNs). Techniques for increasing capacity and flexibility for the inter-rack/pod communications in data centres have drawn remarkable attention in recent years. In this work, we propose a low complexity, reliable, alternative technique for increasing DCN capacity and flexibility through multi-signal modulation onto a single mode VCSEL carrier. A 20 Gbps 4-PAM data signal is directly modulated on a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm, therefore, doubling the network bit rate. Carrier spectral efficiency is further maximized by modulating its phase attribute with a 2 GHz reference frequency (RF) clock signal. We, therefore, simultaneously transmit a 20 Gbps 4-PAM data signal and a phase modulated 2 GHz RF signal using a single mode 10 GHz bandwidth VCSEL carrier. It is the first time a single mode 10 GHz bandwidth VCSEL carrier is reported to simultaneously transmit a directly modulated 4-PAM data signal and a phase modulated RF clock signal. A receiver sensitivity of -10. 52 dBm was attained for a 20 Gbps 4-PAM VCSEL transmission. The 2 GHz phase modulated RF clock signal introduced a power budget penalty of 0.21 dB. Simultaneous distribution of both data and timing signals over shared infrastructure significantly increases the aggregated data rate at different optical network units within the DCN, without expensive optics investment. We further demonstrate on the design of a software-defined digital signal processing assisted receiver to efficiently recover the transmitted signal without employing costly receiver hardware.

Seventh workshop on the role of impurities and defects in silicon device processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-08-01

This workshop is the latest in a series which has looked at technological issues related to the commercial development and success of silicon based photovoltaic (PV) modules. PV modules based on silicon are the most common at present, but face pressure from other technologies in terms of cell performance and cell cost. This workshop addresses a problem which is a factor in the production costs of silicon based PV modules.

Mission Reliability Estimation for Repairable Robot Teams

NASA Technical Reports Server (NTRS)

Trebi-Ollennu, Ashitey; Dolan, John; Stancliff, Stephen

2010-01-01

A mission reliability estimation method has been designed to translate mission requirements into choices of robot modules in order to configure a multi-robot team to have high reliability at minimal cost. In order to build cost-effective robot teams for long-term missions, one must be able to compare alternative design paradigms in a principled way by comparing the reliability of different robot models and robot team configurations. Core modules have been created including: a probabilistic module with reliability-cost characteristics, a method for combining the characteristics of multiple modules to determine an overall reliability-cost characteristic, and a method for the generation of legitimate module combinations based on mission specifications and the selection of the best of the resulting combinations from a cost-reliability standpoint. The developed methodology can be used to predict the probability of a mission being completed, given information about the components used to build the robots, as well as information about the mission tasks. In the research for this innovation, sample robot missions were examined and compared to the performance of robot teams with different numbers of robots and different numbers of spare components. Data that a mission designer would need was factored in, such as whether it would be better to have a spare robot versus an equivalent number of spare parts, or if mission cost can be reduced while maintaining reliability using spares. This analytical model was applied to an example robot mission, examining the cost-reliability tradeoffs among different team configurations. Particularly scrutinized were teams using either redundancy (spare robots) or repairability (spare components). Using conservative estimates of the cost-reliability relationship, results show that it is possible to significantly reduce the cost of a robotic mission by using cheaper, lower-reliability components and providing spares. This suggests that the current design paradigm of building a minimal number of highly robust robots may not be the best way to design robots for extended missions.

Are online learning modules an effective way to deliver hand trauma management continuing medical education to emergency physicians?

PubMed

Williams, Jason G

2014-01-01

The enormity of modern medical knowledge and the rapidity of change have created increased need for ongoing or continuing medical education (CME) for physicians. Online CME is attractive for its availability at any time and any place, low cost and potentially increased effectiveness compared with traditional face-to-face delivery. To determine whether online CME modules are an effective method for delivering plastic surgery CME to primary care physicians. A needs assessment survey was conducted among all emergency and family physicians in Nova Scotia. Results indicated that this type of program was appealing, and that hand trauma related topics were most desired for CME. 7 Lesson Builder (SoftChalk LLC, www.softchalk.com) was used to construct a multimedia e-learning module that was distributed along with a pretest, post-test and feedback questionnaire. Quantitative (pre- and post-test scores) and qualitative (feedback responses) data were analyzed. The 32 participants who completed the study indicated that it was a positive and enjoyable experience, and that there was a need for more resources like this. Compared with pretest scores, there was a significant gain in knowledge following completion of the module (P=0.001). The present study demonstrated that an e-learning format is attractive for this population and effective in increasing knowledge. This positive outcome will lead to development of additional modules.

How performance-contingent reward prospect modulates cognitive control: Increased cue maintenance at the cost of decreased flexibility.

PubMed

Hefer, Carmen; Dreisbach, Gesine

2017-10-01

Growing evidence suggests that reward prospect promotes cognitive stability in terms of increased context or cue maintenance. In 3 Experiments, using different versions of the AX-continuous performance task, we investigated whether this reward effect comes at the cost of decreased cognitive flexibility. Experiment 1 shows that the reward induced increase of cue maintenance perseverates even when reward is no longer available. Experiment 2 shows that this reward effect not only survives the withdrawal of reward but also delays the adaptation to changed task conditions that make cue usage maladaptive. And finally in Experiment 3, it is shown that this reduced flexibility to adapt is observed in a more demanding modified version of the AX-continuous performance task and is even stronger under conditions of sustained reward. Taken together, all 3 Experiments thus speak to the idea that the prospect of reward increases cue maintenance and thereby cognitive stability. This increased cognitive stability however comes at the cost of decreased flexibility in terms of delayed adaptation to new reward and task conditions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Thermal control of power supplies with electronic packaging techniques

NASA Technical Reports Server (NTRS)

1975-01-01

The analysis, design, and development work to reduce the weight and size of a standard modular power supply with a 350 watt output was summarized. By integrating low cost commercial heat pipes in the redesign of this power supply, weight was reduced by 30% from that of the previous design. The temperature was also appreciably reduced, increasing the environmental capability of the unit. A demonstration unit with a 100 watt output and a 15 volt regulator module, plus simulated output modules, was built and tested to evaluate the thermal performance of the redesigned power supply.

Residential photovoltaic module and array requirements study

NASA Technical Reports Server (NTRS)

Nearhoof, S. L.; Oster, J. R.

1979-01-01

Design requirements for photovoltaic modules and arrays used in residential applications were identified. Building codes and referenced standards were reviewed for their applicability to residential photovoltaic array installations. Four installation types were identified - integral (replaces roofing), direct (mounted on top of roofing), stand-off (mounted away from roofing), and rack (for flat or low slope roofs, or ground mounted). Installation costs were developed for these mounting types as a function of panel/module size. Studies were performed to identify optimum module shapes and sizes and operating voltage cost drivers. It is concluded that there are no perceived major obstacles to the use of photovoltaic modules in residential arrays. However, there is no applicable building code category for residential photovoltaic modules and arrays and additional work with standards writing organizations is needed to develop residential module and array requirements.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Xingshu; Silverman, Timothy J.; Zhou, Zhiguang

For commercial one-sun solar modules, up to 80% of the incoming sunlight may be dissipated as heat, potentially raising the temperature 20-30 °C higher than the ambient. In the long term, extreme self-heating erodes efficiency and shortens lifetime, thereby dramatically reducing the total energy output. Therefore, it is critically important to develop effective and practical (and preferably passive) cooling methods to reduce operating temperature of photovoltaic (PV) modules. In this paper, we explore two fundamental (but often overlooked) origins of PV self-heating, namely, sub-bandgap absorption and imperfect thermal radiation. The analysis suggests that we redesign the optical properties of themore » solar module to eliminate parasitic absorption (selective-spectral cooling) and enhance thermal emission (radiative cooling). Comprehensive opto-electro-thermal simulation shows that the proposed techniques would cool one-sun terrestrial solar modules up to 10 °C. As a result, this self-cooling would substantially extend the lifetime for solar modules, with corresponding increase in energy yields and reduced levelized cost of electricity.« less

A Low-Cost Production Method of FeSi2 Power Generation Thermoelectric Modules

NASA Astrophysics Data System (ADS)

Inoue, Hiroyuki; Kobayashi, Takahide; Kato, Masahiko; Yoneda, Seiji

2016-03-01

A method is proposed to reduce the production cost of power generation thermoelectric modules. FeSi2 is employed as the thermoelectric material because of its low cost, low environmental load, and oxidation resistance. The raw materials were prepared in the composition of Fe0.96Si2.1Co0.04 for n-type and Fe0.92Si2.1Mn0.08 for p-type, which were added with 0.5 wt.% Cu as the starting materials. They were sintered without pressure at 1446 K to be formed into elements. The Seebeck coefficient and resistivity at room temperature were determined to be -182 μV/K and 0.13 mΩm for n-type, and 338 μV/K and 1.13 mΩm for p-type, respectively. The brazing conditions of the direct joining between the element and the solder were examined. Pastes of BNi-6, BNi-7 or TB-608T were tried as the solder. TB-608T was useable for metallizing of insulation substrates and joining of thermoelectric elements in order to manufacture thermoelectric modules. The joining strength was determined to be 50 MPa between the alumina plate and the elements. No mechanical failure was observed in the modules after repetition of 10 or more exposures to a heat source of 670 K. No change was found in the internal resistance. The present production method will provide modules with high durability and low production cost, which will enable high-power multi-stage cascade modules at a reasonable cost.

Thermal and other tests of photovoltaic modules performed in natural sunlight

NASA Technical Reports Server (NTRS)

Stultz, J. W.

1978-01-01

The bulk of the testing was the characterization of twenty-nine modules according to their nominal operating cell temperature (NOCT) and the effect on NOCT of changes in module design, various residential roof mounting configurations, and dirt accumulation. Other tests, often performed parallel with the NOCT measurements, evaluated the improvement in electrical performance by cooling the modules with water and by channeling the waste heat into a phase change material (wax). Electrical degradation resulting from the natural marriage of photovoltaic and solar water heating modules was also demonstrated. Cost effectiveness of each of these techniques are evaluated in light of the LSA cost goal of $0.50 per watt.

Uncertainty-based Optimization Algorithms in Designing Fractionated Spacecraft

PubMed Central

Ning, Xin; Yuan, Jianping; Yue, Xiaokui

2016-01-01

A fractionated spacecraft is an innovative application of a distributive space system. To fully understand the impact of various uncertainties on its development, launch and in-orbit operation, we use the stochastic missioncycle cost to comprehensively evaluate the survivability, flexibility, reliability and economy of the ways of dividing the various modules of the different configurations of fractionated spacecraft. We systematically describe its concept and then analyze its evaluation and optimal design method that exists during recent years and propose the stochastic missioncycle cost for comprehensive evaluation. We also establish the models of the costs such as module development, launch and deployment and the impacts of their uncertainties respectively. Finally, we carry out the Monte Carlo simulation of the complete missioncycle costs of various configurations of the fractionated spacecraft under various uncertainties and give and compare the probability density distribution and statistical characteristics of its stochastic missioncycle cost, using the two strategies of timing module replacement and non-timing module replacement. The simulation results verify the effectiveness of the comprehensive evaluation method and show that our evaluation method can comprehensively evaluate the adaptability of the fractionated spacecraft under different technical and mission conditions. PMID:26964755

Braking and Propulsive Impulses Increase with Speed during Accelerated and Decelerated Walking

PubMed Central

Peterson, Carrie L.; Kautz, Steven A.; Neptune, Richard R.

2011-01-01

The ability to accelerate and decelerate is important for daily activities and likely more demanding than maintaining a steady-state walking speed. Walking speed is modulated by anterior-posterior (AP) ground reaction force (GRF) impulses. The purpose of this study was to investigate AP impulses across a wide range of speeds during accelerated and decelerated walking. Kinematic and GRF data were collected from ten healthy subjects walking on an instrumented treadmill. Subjects completed trials at steady-state speeds and at four rates of acceleration and deceleration across a speed range of 0 to 1.8 m/s. Mixed regression models were generated to predict AP impulses, step length and frequency from speed, and joint moment impulses from AP impulses during non-steady-state walking. Braking and propulsive impulses were positively related to speed. The braking impulse had a greater relationship with speed than the propulsive impulse, suggesting that subjects modulate the braking impulse more than the propulsive impulse to change speed. Hip and knee extensor, and ankle plantarflexor moment impulses were positively related to the braking impulse, and knee flexor and ankle plantarflexor moment impulses were positively related to the propulsive impulse. Step length and frequency increased with speed and were near the subjects’ preferred combination at steady-state speeds, at which metabolic cost is minimized in nondisabled walking. Thus, these variables may be modulated to minimize metabolic cost while accelerating and decelerating. The outcomes of this work provide the foundation to investigate motor coordination in pathological subjects in response to the increased task demands of non-steady-state walking. PMID:21356590

The Automated Array Assembly Task of the Low-cost Silicon Solar Array Project, Phase 2

NASA Technical Reports Server (NTRS)

Coleman, M. G.; Grenon, L.; Pastirik, E. M.; Pryor, R. A.; Sparks, T. G.

1978-01-01

An advanced process sequence for manufacturing high efficiency solar cells and modules in a cost-effective manner is discussed. Emphasis is on process simplicity and minimizing consumed materials. The process sequence incorporates texture etching, plasma processes for damage removal and patterning, ion implantation, low pressure silicon nitride deposition, and plated metal. A reliable module design is presented. Specific process step developments are given. A detailed cost analysis was performed to indicate future areas of fruitful cost reduction effort. Recommendations for advanced investigations are included.

How Positive Affect Modulates Cognitive Control: Reduced Perseveration at the Cost of Increased Distractibility

ERIC Educational Resources Information Center

Dreisbach, Gesine; Goschke, Thomas

2004-01-01

A fundamental problem that organisms face in a changing environment is how to regulate dynamically the balance between stable maintenance and flexible switching of goals and cognitive sets. The authors show that positive affect plays an important role in the regulation of this stability-flexibility balance. In a cognitive set-switching paradigm,…

Hybrid Tandem Solar Cells | Photovoltaic Research | NREL

Science.gov Websites

Hybrid Tandem Solar Cells Hybrid Tandem Solar Cells To achieve aggressive cost reductions in photovoltaics (PV) beyond the 6¢/kWh SunShot Initiative 2020 goal, module efficiency must be increased beyond on a silicon platform and that aim to provide viable prototypes for commercialization. PV Research

Development of an Augmented Reality Game to Teach Abstract Concepts in Food Chemistry

ERIC Educational Resources Information Center

Crandall, Philip G.; Engler, Robert K.; Beck, Dennis E.; Killian, Susan A.; O'Bryan, Corliss A.; Jarvis, Nathan; Clausen, Ed

2015-01-01

One of the most pressing issues for many land grant institutions is the ever increasing cost to build and operate wet chemistry laboratories. A partial solution is to develop computer-based teaching modules that take advantage of animation, web-based or off-campus learning experiences directed at engaging students' creative experiences. We…

VCSEL-based optical transceiver module for high-speed short-reach interconnect

NASA Astrophysics Data System (ADS)

Yagisawa, Takatoshi; Oku, Hideki; Mori, Tatsuhiro; Tsudome, Rie; Tanaka, Kazuhiro; Daikuhara, Osamu; Komiyama, Takeshi; Ide, Satoshi

2017-02-01

Interconnects have been more important in high-performance computing systems and high-end servers beside its improvements in computing capability. Recently, active optical cables (AOCs) have started being used for this purpose instead of conventionally used copper cables. The AOC enables to extend the transmission distance of the high-speed signals dramatically by its broadband characteristics, however, it tend to increase the cost. In this paper, we report our developed quad small form-factor pluggable (QSFP) AOC utilizing cost-effective optical-module technologies. These are a unique structure using generally used flexible printed circuit (FPC) in combination with an optical waveguide that enables low-cost high-precision assembly with passive alignment, a lens-integrated ferrule that improves productivity by eliminating a polishing process for physical contact of standard PMT connector for the optical waveguide, and an overdrive technology that enables 100 Gb/s (25 Gb/s × 4-channel) operation with low-cost 14 Gb/s vertical-cavity surfaceemitting laser (VCSEL) array. The QSFP AOC demonstrated clear eye opening and error-free operation at 100 Gb/s with high yield rate even though the 14 Gb/s VCSEL was used thanks to the low-coupling loss resulting from the highprecision alignment of optical devices and the over-drive technology.

Receiver bandwidth effects on complex modulation and detection using directly modulated lasers.

PubMed

Yuan, Feng; Che, Di; Shieh, William

2016-05-01

Directly modulated lasers (DMLs) have long been employed for short- and medium-reach optical communications due to their low cost. Recently, a new modulation scheme called complex modulated DMLs has been demonstrated showing a significant optical signal to noise ratio sensitivity enhancement compared with the traditional intensity-only detection scheme. However, chirp-induced optical spectrum broadening is inevitable in complex modulated systems, which may imply a need for high-bandwidth receivers. In this Letter, we study the impact of receiver bandwidth effects on the performance of complex modulation and coherent detection systems based on DMLs. We experimentally demonstrate that such systems exhibit a reasonable tolerance for the reduced receiver bandwidth. For 10 Gbaud 4-level pulse amplitude modulation signals, the required electrical bandwidth is as low as 8.5 and 7.5 GHz for 7% and 20% forward error correction, respectively. Therefore, it is feasible to realize DML-based complex modulated systems using cost-effective receivers with narrow bandwidth.

Motivational intensity modulates the effects of positive emotions on set shifting after controlling physiological arousal.

PubMed

Zhou, Ya; Siu, Angela F Y

2015-12-01

Recent research on the construct of emotion suggests the integration of a motivational dimension into the traditional two-dimension (subjective valence and physiological arousal) model. The motivational intensity of an emotional state should be taken into account while investigating the emotion-cognition relationship. This study examined how positive emotional states varying in motivational intensity influenced set shifting, after controlling the potential confounding impacts of physiological arousal. In Experiment 1, 155 volunteers performed a set-shifting task after being randomly assigned to five states: high- vs. low-motivating positive affect (interest vs. serenity), high- vs. low-motivating negative affect (disgust vs. anxiety), and neutral state. Eighty-five volunteers participated in Experiment 2, which further examined the effects of higher vs. lower degree of interest. Both experiments measured and compared participants' physiological arousal (blood pressure and pulse rate) under the normal and experimental conditions as the covariate. Results showed no difference in switching performance between the neutral and serenity groups. As compared with the neutral state, the high-motivating positive affect significantly increased set-switching reaction time costs, but reduced error rate costs; the higher the motivational intensity, the greater the time-costs impairment. This indicates a role of the high-motivating positive affect in regulating the balance between the flexible and stable cognitive control. Motivational intensity also modulated the effects of negative emotional states, i.e., disgust caused a larger increase in time costs than anxiety. Further exploration into neurobiological mechanisms that may mediate the emotional effects on set shifting is warranted. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Evaluation of Delivery Costs for External Beam Radiation Therapy and Brachytherapy for Locally Advanced Cervical Cancer Using Time-Driven Activity-Based Costing.

PubMed

Bauer-Nilsen, Kristine; Hill, Colin; Trifiletti, Daniel M; Libby, Bruce; Lash, Donna H; Lain, Melody; Christodoulou, Deborah; Hodge, Constance; Showalter, Timothy N

2018-01-01

To evaluate the delivery costs, using time-driven activity-based costing, and reimbursement for definitive radiation therapy for locally advanced cervical cancer. Process maps were created to represent each step of the radiation treatment process and included personnel, equipment, and consumable supplies used to deliver care. Personnel were interviewed to estimate time involved to deliver care. Salary data, equipment purchasing information, and facilities costs were also obtained. We defined the capacity cost rate (CCR) for each resource and then calculated the total cost of patient care according to CCR and time for each resource. Costs were compared with 2016 Medicare reimbursement and relative value units (RVUs). The total cost of radiation therapy for cervical cancer was $12,861.68, with personnel costs constituting 49.8%. Brachytherapy cost $8610.68 (66.9% of total) and consumed 423 minutes of attending radiation oncologist time (80.0% of total). External beam radiation therapy cost $4055.01 (31.5% of total). Personnel costs were higher for brachytherapy than for the sum of simulation and external beam radiation therapy delivery ($4798.73 vs $1404.72). A full radiation therapy course provides radiation oncologists 149.77 RVUs with intensity modulated radiation therapy or 135.90 RVUs with 3-dimensional conformal radiation therapy, with total reimbursement of $23,321.71 and $16,071.90, respectively. Attending time per RVU is approximately 4-fold higher for brachytherapy (5.68 minutes) than 3-dimensional conformal radiation therapy (1.63 minutes) or intensity modulated radiation therapy (1.32 minutes). Time-driven activity-based costing was used to calculate the total cost of definitive radiation therapy for cervical cancer, revealing that brachytherapy delivery and personnel resources constituted the majority of costs. However, current reimbursement policy does not reflect the increased attending physician effort and delivery costs of brachytherapy. We hypothesize that the significant discrepancy between treatment costs and physician effort versus reimbursement may be a potential driver of reported national trends toward poor compliance with brachytherapy, and we suggest re-evaluation of payment policies to incentivize quality care. Copyright © 2017 Elsevier Inc. All rights reserved.

Experimental evolution reveals antagonistic pleiotropy in reproductive timing but not life span in Caenorhabditis elegans.

PubMed

Anderson, Jennifer L; Reynolds, Rose M; Morran, Levi T; Tolman-Thompson, Julie; Phillips, Patrick C

2011-12-01

Many mutations that dramatically extend life span in model organisms come with substantial fitness costs. Although these genetic manipulations provide valuable insight into molecular modulators of life span, it is currently unclear whether life-span extension is unavoidably linked to fitness costs. To examine this relationship, we evolved a genetically heterogeneous population of Caenorhabditis elegans for 47 generations, selecting for early fecundity. We asked whether an increase in early fecundity would necessitate a decrease in longevity or late fecundity (antagonistic pleiotropy). Caenorhabditis elegans experimentally evolved for increased early reproduction and decreased late reproduction but suffered no total fitness or life-span costs. Given that antagonistic pleiotropy among these traits has been previously demonstrated in some cases, we conclude that the genetic constraint is not absolute, that is, it is possible to uncouple longevity from early fecundity using genetic variation segregating within and among natural populations.

Encapsulation task of the low-cost silicon solar array project. Investigation of test methods, material properties, and processes for solar cell encapsulants

NASA Technical Reports Server (NTRS)

Willis, P. B.; Baum, B.; White, R. A.

1978-01-01

The results of an investigation of solar module encapsulation systems applicable to the Low-Cost Solar Array Project 1986 cost and performance goals are presented. Six basic construction elements were identified and their specific uses in module construction defined. A uniform coating basis was established for each element. The survey results were also useful in revealing price ranges for classes of materials and estimating the cost allocation for each element within the encapsulating cost goal. The six construction elements were considered to be substrates, superstrates, pottants, adhesives, outer covers and back covers.

Integrated residential photovoltaic array development

NASA Technical Reports Server (NTRS)

Shepard, N. F., Jr.

1981-01-01

Three basic module design concepts were analyzed with respect to both production and installation costs. The results of this evaluation were used to synthesize a fourth design which incorporates the best features of these initial concepts to produce a module/array design approach which offers the promise of a substantial reduction in the installed cost of a residential array. A unique waterproofing and mounting scheme was used to reduce the cost of installing an integral array while still maintaining a high probability that the installed array will be watertight for the design lifetime of the system. This recommended concept will also permit the array to be mounted as a direct or stand-off installation with no changes to the module design.

Multi-Stage Target Tracking with Drift Correction and Position Prediction

NASA Astrophysics Data System (ADS)

Chen, Xin; Ren, Keyan; Hou, Yibin

2018-04-01

Most existing tracking methods are hard to combine accuracy and performance, and do not consider the shift between clarity and blur that often occurs. In this paper, we propound a multi-stage tracking framework with two particular modules: position prediction and corrective measure. We conduct tracking based on correlation filter with a corrective measure module to increase both performance and accuracy. Specifically, a convolutional network is used for solving the blur problem in realistic scene, training methodology that training dataset with blur images generated by the three blur algorithms. Then, we propose a position prediction module to reduce the computation cost and make tracker more capable of fast motion. Experimental result shows that our tracking method is more robust compared to others and more accurate on the benchmark sequences.

LANDSAT/MMS propulsion module design. Tas4.4: Concept design

NASA Technical Reports Server (NTRS)

Mansfield, J. M.; Etheridge, F. G.; Indrikis, J.

1976-01-01

Evaluations are presented of alternative LANDSAT follow-on launch configurations to derive the propulsion requirements for the multimission modular spacecraft (MMS). Two basic types were analyzed including use of conventional launch vehicles and shuttle supported missions. It was concluded that two sizes of modular hydrazine propulsion modules would provide the most cost-effective combination for future missions of this spacecraft. Conceptual designs of the selected propulsion modules were performed to the depth permitting determination of mass properties and estimated costs.

Cost reduction for communication satellites in the 1800 to 2600 kg (GEO) class by a standardized propulsion module (OPM)

NASA Astrophysics Data System (ADS)

Koelle, D. E.; Mueller, W.; Schweig, H.

1985-10-01

The standardized propulsion module for future spacecraft in the 1800-2700 kg class is described. The definition of the propulsion system and its thrust level are addressed, and the design of the orbital propulsion module (OPM) is shown and described. The masses of various components are given. The OPM application and size optimization for the Ariane 4 launchers are examined, and the cost-saving aspects of OPM and its space applications are discussed.

Emotional modulation of control dilemmas: the role of positive affect, reward, and dopamine in cognitive stability and flexibility.

PubMed

Goschke, Thomas; Bolte, Annette

2014-09-01

Goal-directed action in changing environments requires a dynamic balance between complementary control modes, which serve antagonistic adaptive functions (e.g., to shield goals from competing responses and distracting information vs. to flexibly switch between goals and behavioral dispositions in response to significant changes). Too rigid goal shielding promotes stability but incurs a cost in terms of perseveration and reduced flexibility, whereas too weak goal shielding promotes flexibility but incurs a cost in terms of increased distractibility. While research on cognitive control has long been conducted relatively independently from the study of emotion and motivation, it is becoming increasingly clear that positive affect and reward play a central role in modulating cognitive control. In particular, evidence from the past decade suggests that positive affect not only influences the contents of cognitive processes, but also modulates the balance between complementary modes of cognitive control. In this article we review studies from the past decade that examined effects of induced positive affect on the balance between cognitive stability and flexibility with a focus on set switching and working memory maintenance and updating. Moreover, we review recent evidence indicating that task-irrelevant positive affect and performance-contingent rewards exert different and sometimes opposite effects on cognitive control modes, suggesting dissociations between emotional and motivational effects of positive affect. Finally, we critically review evidence for the popular hypothesis that effects of positive affect may be mediated by dopaminergic modulations of neural processing in prefrontal and striatal brain circuits, and we refine this "dopamine hypothesis of positive affect" by specifying distinct mechanisms by which dopamine may mediate effects of positive affect and reward on cognitive control. We conclude with a discussion of limitations of current research, point to central unresolved questions and outline perspective for future research on affective and motivational modulations of cognitive control modes. Copyright © 2014. Published by Elsevier Ltd.

Administrative considerations when implementing ACS/APDS Skills Curriculum.

PubMed

Rooney, Deborah; Pugh, Carla; Auyang, Edward; Hungness, Eric; Darosa, Debra

2010-05-01

With time and cost constraints, implementing an effective, yet efficient, skills curriculum poses significant challenges. Our purpose is to describe a successful curriculum administrative structure that promoted faculty buy-in and accountability, learner responsibility, and acceptable resource usage. A total of 14 American College of Surgery (ACS) modules were included in the postgraduate year 1 curriculum. Before arrival, 2 modules were sent to newly matched residents. Remaining modules were administered over a 4-month period, with integrated, independent practice opportunities, as well as 4 mentored and 1 peer practice sessions. A total of 2 verifications of proficiency (VOP) progress exams and 1 final comprehensive VOP were administered. To promote faculty ownership, 1 faculty member was asked to lead each module. Module leaders attended an orientation and development session, and created an instructional management plan. Each module was taught by the leader and 2 additional faculty coinstructors, and evaluated by residents. Equipment, resource costs, and man-hours were tracked. Faculty buy-in was demonstrated by enthusiastic participation, with only 2 absences. Residents gave high ratings to all the modules (range, 4.22-4.89/5). Curriculum costs were approximately $21,500, reduced from potential costs of $187,000 if all simulators would have been purchased new. The estimated budget for year 2 is $17,000. It is critical for new curricula to have resident and faculty buy-in, accountability for quality teaching and learning, and reasonable resource use. We provide suggestions for structuring a curriculum to ensure accomplishment of these important drivers. Copyright 2010 Mosby, Inc. All rights reserved.

A Low-Cost, Hands-on Module to Characterize Antimicrobial Compounds Using an Interdisciplinary, Biophysical Approach

PubMed Central

Kaushik, Karishma S.; Kessel, Ashley; Ratnayeke, Nalin; Gordon, Vernita D.

2015-01-01

We have developed a hands-on experimental module that combines biology experiments with a physics-based analytical model in order to characterize antimicrobial compounds. To understand antibiotic resistance, participants perform a disc diffusion assay to test the antimicrobial activity of different compounds and then apply a diffusion-based analytical model to gain insights into the behavior of the active antimicrobial component. In our experience, this module was robust, reproducible, and cost-effective, suggesting that it could be implemented in diverse settings such as undergraduate research, STEM (science, technology, engineering, and math) camps, school programs, and laboratory training workshops. By providing valuable interdisciplinary research experience in science outreach and education initiatives, this module addresses the paucity of structured training or education programs that integrate diverse scientific fields. Its low-cost requirements make it especially suitable for use in resource-limited settings. PMID:25602254

Low-cost, digital lock-in module with external reference for coating glass transmission/reflection spectrophotometer

NASA Astrophysics Data System (ADS)

Alonso, R.; Villuendas, F.; Borja, J.; Barragán, L. A.; Salinas, I.

2003-05-01

A versatile, low-cost, digital signal processor (DSP) based lock-in module with external reference is described. This module is used to implement an industrial spectrophotometer for measuring spectral transmission and reflection of automotive and architectonic coating glasses over the ultraviolet, visible and near-infrared wavelength range. The light beams are modulated with an optical chopper. A digital phase-locked loop (DPLL) is used to lock the lock-in to the chop frequency. The lock-in rejects the ambient radiation and permits the spectrophotometer to work in the presence of ambient light. The algorithm that implements the dual lock-in and the DPLL in the DSP56002 evaluation module from Motorola is described. The use of a DSP allows implementation of the lock-in and DPLL by software, which gives flexibility and programmability to the system. Lock-in module cost, under 300 euro, is an important parameter taking into account that two modules are used in the system. Besides, the algorithms implemented in this DSP can be directly implemented in the latest DSP generations. The DPLL performance and the spectrophotometer are characterized. Capture and lock DPLL ranges have been measured and checked to be greater than the chop frequency drifts. The lock-in measured frequency response shows that the lock-in performs as theoretically predicted.

Interdisciplinary pharmacometrics linking oseltamivir pharmacology, influenza epidemiology and health economics to inform antiviral use in pandemics.

PubMed

Kamal, Mohamed A; Smith, Patrick F; Chaiyakunapruk, Nathorn; Wu, David B C; Pratoomsoot, Chayanin; Lee, Kenneth K C; Chong, Huey Yi; Nelson, Richard E; Nieforth, Keith; Dall, Georgina; Toovey, Stephen; Kong, David C M; Kamauu, Aaron; Kirkpatrick, Carl M; Rayner, Craig R

2017-07-01

A modular interdisciplinary platform was developed to investigate the economic impact of oseltamivir treatment by dosage regimen under simulated influenza pandemic scenarios. The pharmacology module consisted of a pharmacokinetic distribution of oseltamivir carboxylate daily area under the concentration-time curve at steady state (simulated for 75 mg and 150 mg twice daily regimens for 5 days) and a pharmacodynamic distribution of viral shedding duration obtained from phase II influenza inoculation data. The epidemiological module comprised a susceptible, exposed, infected, recovered (SEIR) model to which drug effect on the basic reproductive number (R 0 ), a measure of transmissibility, was linked by reduction of viral shedding duration. The number of infected patients per population of 100 000 susceptible individuals was simulated for a series of pandemic scenarios, varying oseltamivir dose, R 0 (1.9 vs. 2.7), and drug uptake (25%, 50%, and 80%). The number of infected patients for each scenario was entered into the health economics module, a decision analytic model populated with branch probabilities, disease utility, costs of hospitalized patients developing complications, and case-fatality rates. Change in quality-adjusted life years was determined relative to base case. Oseltamivir 75 mg relative to no treatment reduced the median number of infected patients, increased change in quality-adjusted life years by deaths averted, and was cost-saving under all scenarios; 150 mg relative to 75 mg was not cost effective in low transmissibility scenarios but was cost saving in high transmissibility scenarios. This methodological study demonstrates proof of concept that the disciplines of pharmacology, disease epidemiology and health economics can be linked in a single quantitative framework. © 2017 The British Pharmacological Society.

Code-modulated interferometric imaging system using phased arrays

NASA Astrophysics Data System (ADS)

Chauhan, Vikas; Greene, Kevin; Floyd, Brian

2016-05-01

Millimeter-wave (mm-wave) imaging provides compelling capabilities for security screening, navigation, and bio- medical applications. Traditional scanned or focal-plane mm-wave imagers are bulky and costly. In contrast, phased-array hardware developed for mass-market wireless communications and automotive radar promise to be extremely low cost. In this work, we present techniques which can allow low-cost phased-array receivers to be reconfigured or re-purposed as interferometric imagers, removing the need for custom hardware and thereby reducing cost. Since traditional phased arrays power combine incoming signals prior to digitization, orthogonal code-modulation is applied to each incoming signal using phase shifters within each front-end and two-bit codes. These code-modulated signals can then be combined and processed coherently through a shared hardware path. Once digitized, visibility functions can be recovered through squaring and code-demultiplexing operations. Pro- vided that codes are selected such that the product of two orthogonal codes is a third unique and orthogonal code, it is possible to demultiplex complex visibility functions directly. As such, the proposed system modulates incoming signals but demodulates desired correlations. In this work, we present the operation of the system, a validation of its operation using behavioral models of a traditional phased array, and a benchmarking of the code-modulated interferometer against traditional interferometer and focal-plane arrays.

Development of ultracapacitor modules for 42-V automotive electrical systems

NASA Astrophysics Data System (ADS)

Jung, Do Yang; Kim, Young Ho; Kim, Sun Wook; Lee, Suck-Hyun

Two types of ultracapacitor modules have been developed for use as energy-storage devices for 42-V systems in automobiles. The modules show high performance and good reliability in terms of discharge and recharge capability, long-term endurance, and high energy and power. During a 42-V system simulation test of 6-kW power boosting/regenerative braking, the modules demonstrate very good performance. In high-power applications such as 42-V and hybrid vehicle systems, ultracapacitors have many merits compared with batteries, especially with respect to specific power at high rate, thermal stability, charge-discharge efficiency, and cycle-life. Ultracapacitors are also very safe, reliable and environmentally friendly. The cost of ultracapacitors is still high compared with batteries because of the low production scale, but is decreasing very rapidly. It is estimated that the cost of ultracapacitors will decrease to US$ 300 per 42-V module in the near future. Also, the maintenance cost of the ultracapacitor is nearly zero because of its high cycle-life. Therefore, the combined cost of the capacitor and maintenance will be lower than that of batteries in the near future. Overall, comparing performance, price and other parameters of ultracapacitors with batteries, ultracapacitors are the most likely candidate for energy-storage in 42-V systems.

Reliability and cost analysis methods

NASA Technical Reports Server (NTRS)

Suich, Ronald C.

1991-01-01

In the design phase of a system, how does a design engineer or manager choose between a subsystem with .990 reliability and a more costly subsystem with .995 reliability? When is the increased cost justified? High reliability is not necessarily an end in itself but may be desirable in order to reduce the expected cost due to subsystem failure. However, this may not be the wisest use of funds since the expected cost due to subsystem failure is not the only cost involved. The subsystem itself may be very costly. We should not consider either the cost of the subsystem or the expected cost due to subsystem failure separately but should minimize the total of the two costs, i.e., the total of the cost of the subsystem plus the expected cost due to subsystem failure. This final report discusses the Combined Analysis of Reliability, Redundancy, and Cost (CARRAC) methods which were developed under Grant Number NAG 3-1100 from the NASA Lewis Research Center. CARRAC methods and a CARRAC computer program employ five models which can be used to cover a wide range of problems. The models contain an option which can include repair of failed modules.

Estimating the costs of intensity-modulated and 3-dimensional conformal radiotherapy in Ontario.

PubMed

Yong, J H E; McGowan, T; Redmond-Misner, R; Beca, J; Warde, P; Gutierrez, E; Hoch, J S

2016-06-01

Radiotherapy is a common treatment for many cancers, but up-to-date estimates of the costs of radiotherapy are lacking. In the present study, we estimated the unit costs of intensity-modulated radiotherapy (imrt) and 3-dimensional conformal radiotherapy (3D-crt) in Ontario. An activity-based costing model was developed to estimate the costs of imrt and 3D-crt in prostate cancer. It included the costs of equipment, staff, and supporting infrastructure. The framework was subsequently adapted to estimate the costs of radiotherapy in breast cancer and head-and-neck cancer. We also tested various scenarios by varying the program maturity and the use of volumetric modulated arc therapy (vmat) alongside imrt. From the perspective of the health care system, treating prostate cancer with imrt and 3D-crt respectively cost $12,834 and $12,453 per patient. The cost of radiotherapy ranged from $5,270 to $14,155 and was sensitive to analytic perspective, radiation technique, and disease site. Cases of head-and-neck cancer were the most costly, being driven by treatment complexity and fractions per treatment. Although imrt was more costly than 3D-crt, its cost will likely decline over time as programs mature and vmat is incorporated. Our costing model can be modified to estimate the costs of 3D-crt and imrt for various disease sites and settings. The results demonstrate the important role of capital costs in studies of radiotherapy cost from a health system perspective, which our model can accommodate. In addition, our study established the need for future analyses of imrt cost to consider how vmat affects time consumption.

Low-cost encapsulation materials for terrestrial solar cell modules

NASA Technical Reports Server (NTRS)

Cuddihy, E. F.; Baum, B.; Willis, P.

1979-01-01

The paper presents the findings of material surveys intended to identify low cost materials which could be functional as encapsulants (by 1986) for terrestrial solar cell modules. Economic analyses have indicated that in order to meet the low cost goal of $2.70 per sq m, some or all of the following material technologies must be developed or advanced: (1) UV screening outer covers; (2) elastomeric acrylics; (3) weatherproofing and waterproofing of structural wood and paper products; (4) transparent UV stabilizers for the UV-sensitive transparent pottants; and (5) cost-effective utilization of silicone and fluorocarbon materials.

Cost-effectiveness analysis of intensity-modulated radiation therapy with normal and hypofractionated schemes for the treatment of localised prostate cancer.

PubMed

Zemplényi, A T; Kaló, Z; Kovács, G; Farkas, R; Beöthe, T; Bányai, D; Sebestyén, Z; Endrei, D; Boncz, I; Mangel, L

2018-01-01

The aim of our analysis was to compare the cost-effectiveness of high-dose intensity-modulated radiation therapy (IMRT) and hypofractionated intensity-modulated radiation therapy (HF-IMRT) versus conventional dose three-dimensional radiation therapy (3DCRT) for the treatment of localised prostate cancer. A Markov model was constructed to calculate the incremental quality-adjusted life years and costs. Transition probabilities, adverse events and utilities were derived from relevant systematic reviews. Microcosting in a large university hospital was applied to calculate cost vectors. The expected mean lifetime cost of patients undergoing 3DCRT, IMRT and HF-IMRT were 7,160 euros, 6,831 euros and 6,019 euros respectively. The expected quality-adjusted life years (QALYs) were 5.753 for 3DCRT, 5.956 for IMRT and 5.957 for HF-IMRT. Compared to 3DCRT, both IMRT and HF-IMRT resulted in more health gains at a lower cost. It can be concluded that high-dose IMRT is not only cost-effective compared to the conventional dose 3DCRT but, when used with a hypofractionation scheme, it has great cost-saving potential for the public payer and may improve access to radiation therapy for patients. © 2016 John Wiley & Sons Ltd.

Can IR scene projectors reduce total system cost?

NASA Astrophysics Data System (ADS)

Ginn, Robert; Solomon, Steven

2006-05-01

There is an incredible amount of system engineering involved in turning the typical infrared system needs of probability of detection, probability of identification, and probability of false alarm into focal plane array (FPA) requirements of noise equivalent irradiance (NEI), modulation transfer function (MTF), fixed pattern noise (FPN), and defective pixels. Unfortunately, there are no analytic solutions to this problem so many approximations and plenty of "seat of the pants" engineering is employed. This leads to conservative specifications, which needlessly drive up system costs by increasing system engineering costs, reducing FPA yields, increasing test costs, increasing rework and the never ending renegotiation of requirements in an effort to rein in costs. These issues do not include the added complexity to the FPA factory manager of trying to meet varied, and changing, requirements for similar products because different customers have made different approximations and flown down different specifications. Scene generation technology may well be mature and cost effective enough to generate considerable overall savings for FPA based systems. We will compare the costs and capabilities of various existing scene generation systems and estimate the potential savings if implemented at several locations in the IR system fabrication cycle. The costs of implementing this new testing methodology will be compared to the probable savings in systems engineering, test, rework, yield improvement and others. The diverse requirements and techniques required for testing missile warning systems, missile seekers, and FLIRs will be defined. Last, we will discuss both the hardware and software requirements necessary to meet the new test paradigm and discuss additional cost improvements related to the incorporation of these technologies.

Interpreting Financial Results. Financial Management Module. Operational Management Programme. Increasing Opportunities for Supervisors and Managers.

ERIC Educational Resources Information Center

Adamson, Jan; And Others

One of a series of three self-instructional units, these materials are aimed at helping British hotel and catering managers improve profits and/or reduce costs in their areas of responsibility. Following an introduction and a paragraph on how to use the unit, section 1 covers how to use management information. The section includes these trainee…

Making Financial Decisions. Financial Management Module. Operational Management Programme. Increasing Opportunities for Supervisors and Managers.

ERIC Educational Resources Information Center

Adamson, Jan; And Others

One of a series of three self-instructional units, these materials are aimed at helping British hotel and catering managers improve profits and/or reduce costs in their areas of responsibility. Following a paragraph on how to use the unit and an introduction, section 1 covers control levels as the framework for making decisions. The section…

A Web-Based Computer-Aided Learning Module for an Anatomy Course Using Open Source Image Mapping Software

ERIC Educational Resources Information Center

Carleton, Renee E.

2012-01-01

Computer-aided learning (CAL) is used increasingly to teach anatomy in post-secondary programs. Studies show that augmentation of traditional cadaver dissection and model examination by CAL can be associated with positive student learning outcomes. In order to reduce costs associated with the purchase of skeletons and models and to encourage study…

A method of extracting ontology module using concept relations for sharing knowledge in mobile cloud computing environment.

PubMed

Lee, Keonsoo; Rho, Seungmin; Lee, Seok-Won

2014-01-01

In mobile cloud computing environment, the cooperation of distributed computing objects is one of the most important requirements for providing successful cloud services. To satisfy this requirement, all the members, who are employed in the cooperation group, need to share the knowledge for mutual understanding. Even if ontology can be the right tool for this goal, there are several issues to make a right ontology. As the cost and complexity of managing knowledge increase according to the scale of the knowledge, reducing the size of ontology is one of the critical issues. In this paper, we propose a method of extracting ontology module to increase the utility of knowledge. For the given signature, this method extracts the ontology module, which is semantically self-contained to fulfill the needs of the service, by considering the syntactic structure and semantic relation of concepts. By employing this module, instead of the original ontology, the cooperation of computing objects can be performed with less computing load and complexity. In particular, when multiple external ontologies need to be combined for more complex services, this method can be used to optimize the size of shared knowledge.

Operation and maintenance cost data for residential photovoltaic modules/panels

NASA Technical Reports Server (NTRS)

Oster, J. R., Jr.; Zaremski, D. R., Jr.; Albert, E. M.; Hawkins, S. L.

1980-01-01

Costs associated with the operation and maintenance of residential photovoltaic modules and arrays are studied. Six basic topics related to operation and maintenance to photovoltaic arrays are investigated: maintenance; cleaning; panel replacement; gasket repair/replacement; wiring repair/replacement; and termination repair/replacement. The effects of the mounting types (rack mount, stand off mount, direct mount and integral mount) and the installation/replacement type (sequential, partial interruption and independent) are identified and described. Methods of reducing maintenance costs are suggested.

High-Rate Wireless Airborne Network Demonstration (HiWAND) Flight Test Results

NASA Technical Reports Server (NTRS)

Franz, Russell

2008-01-01

An increasing number of flight research and airborne science experiments now contain network-ready systems that could benefit from a high-rate bidirectional air-to-ground network link. A prototype system, the High-Rate Wireless Airborne Network Demonstration, was developed from commercial off-the-shelf components while leveraging the existing telemetry infrastructure on the Western Aeronautical Test Range. This approach resulted in a cost-effective, long-range, line-of-sight network link over the S and the L frequency bands using both frequency modulation and shaped-offset quadrature phase-shift keying modulation. This report discusses system configuration and the flight test results.

Performance analysis of communication links based on VCSEL and silicon photonics technology for high-capacity data-intensive scenario.

PubMed

Boletti, A; Boffi, P; Martelli, P; Ferrario, M; Martinelli, M

2015-01-26

To face the increased demand for bandwidth, cost-effectiveness and simplicity of future Ethernet data communications, a comparison between two different solutions based on directly-modulated VCSEL sources and Silicon Photonics technologies is carried out. Also by exploiting 4-PAM modulation, the transmission of 50-Gb/s and beyond capacity per channel is analyzed by means of BER performance. Applications for optical backplane, very short reach and in case of client-optics networks and intra and inter massive data centers communications (up to 10 km) are taken into account. A comparative analysis based on the power consumption is also proposed.

Lock-in imaging with synchronous digital mirror demodulation

NASA Astrophysics Data System (ADS)

Bush, Michael G.

2010-04-01

Lock-in imaging enables high contrast imaging in adverse conditions by exploiting a modulated light source and homodyne detection. We report results on a patent pending lock-in imaging system fabricated from commercial-off-theshelf parts utilizing standard cameras and a spatial light modulator. By leveraging the capabilities of standard parts we are able to present a low cost, high resolution, high sensitivity camera with applications in search and rescue, friend or foe identification (IFF), and covert surveillance. Different operating modes allow the same instrument to be utilized for dual band multispectral imaging or high dynamic range imaging, increasing the flexibility in different operational settings.

High-Rate Wireless Airborne Network Demonstration (HiWAND) Flight Test Results

NASA Technical Reports Server (NTRS)

Franz, Russell

2007-01-01

An increasing number of flight research and airborne science experiments now contain network-ready systems that could benefit from a high-rate bidirectional air-to-ground network link. A prototype system, the High-Rate Wireless Airborne Network Demonstration, was developed from commercial off-the-shelf components while leveraging the existing telemetry infrastructure on the Western Aeronautical Test Range. This approach resulted in a cost-effective, long-range, line-of-sight network link over the S and the L frequency bands using both frequency modulation and shaped-offset quadrature phase-shift keying modulation. This paper discusses system configuration and the flight test results.

Land Application of Wastes: An Educational Program. Treatment Systems, Effluent Qualities, and Costs - Module 4, Objectives, Script, and Booklet.

ERIC Educational Resources Information Center

Clarkson, W. W.; And Others

This module describes the following conventional treatment systems and evaluates their use as pretreatment steps for land application: preliminary, primary, secondary, disinfection, and advanced waste treatment. Effluent qualities are summarized, a brief discussion of application systems is given, and cost comparisons are discussed in some detail.…

With a little help from my kin: barn swallow nestlings modulate solicitation of parental care according to nestmates' need.

PubMed

Romano, Andrea; Caprioli, M; Boncoraglio, G; Saino, N; Rubolini, D

2012-09-01

In altricial species, offspring competing for access to limiting parental resources (e.g. food) are selected to achieve an optimal balance between the costs of scrambling for food, the benefits of being fed and the indirect costs of subtracting food to relatives. As the marginal benefits of acquiring additional food decrease with decreasing levels of need, satiated offspring should be prone to favour access to food by their needy kin, thus enhancing their own indirect fitness, while concomitantly reducing costs of harsh competition with hungry broodmates. We tested this prediction in feeding trials of barn swallow (Hirundo rustica) nestlings by comparing begging behaviour and food intake of two similar-sized nestmates, one of which was food-deprived (FD). Non-food-deprived (NFD) offspring modulated begging intensity depending on their nestmate's need: when competing with FD nestmates, NFD nestlings reduced both the intensity and frequency of begging displays compared to themselves in the control trial before food deprivation. Hence, NFD nestlings reduced their competitiveness to the advantage of FD nestmates, which obtained more feedings and showed a threefold larger increase in body mass. Moderation of individual selfishness can therefore be adaptive in the presence of a needier kin, because the indirect fitness benefits of promoting its condition can outweigh the costs of forgoing being fed, and because it limits the cost of begging escalation against a vigorous competitor. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Increasing faculty participation in resident education and providing cost-effective self-assessment module credit to faculty through resident-generated didactics.

PubMed

Kim, Hyun; Malatesta, Theresa M; Anné, Pramila R; McAna, John; Bar-Ad, Voichita; Dicker, Adam P; Den, Robert B

Board certified radiation oncologists and medical physicists are required to earn self-assessment module (SAM) continuing medical education (CME) credit, which may require travel costs or usage fees. Data indicate that faculty participation in resident teaching activities is beneficial to resident education. Our hypothesis was that providing the opportunity to earn SAM credit in resident didactics would increase faculty participation in and improve resident education. SAM applications, comprising CME certified category 1 resident didactic lectures and faculty-generated questions with respective answers, rationales, and references, were submitted to the American Board of Radiology for formal review. Surveys were distributed to assess main academic campus physician, affiliate campus physician, physicist, and radiation oncology resident impressions regarding the quality of the lectures. Survey responses were designed in Likert-scale format. Sign-test was performed with P < .05 considered statistically different from neutral. First submission SAM approval was obtained for 9 of 9 lectures to date. A total of 52 SAM credits have been awarded to 4 physicists and 7 attending physicians. Main academic campus physician and affiliate campus physician attendance increased from 20% and 0%, respectively, over the 12 months preceding CME/SAM lectures, to 55.6% and 20%, respectively. Survey results indicated that the change to SAM lectures increased the quality of resident lectures (P = .001), attending physician participation in resident education (P < .0001), physicist involvement in medical resident education (P = .0006), and faculty motivation to attend resident didactics (P = .004). Residents reported an increased amount of time required to prepare lectures (P = .008). We are the first department, to our knowledge, to offer SAM credit to clinical faculty for participation in resident-generated didactics. Offering SAM credit at resident lectures is a cost-effective alternative to purchasing SAM resources, increases faculty attendance, and may improve the quality of radiation oncology resident education. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Excimer laser annealing to fabricate low cost solar cells

NASA Technical Reports Server (NTRS)

1984-01-01

The objective is to show whether or not pulsed excimer laser annealing (PELA) of ion-implanted junctions is a cost effective replacement for diffused junctions in fabricating crystalline silicon solar cells. The preliminary economic analysis completed shows that the use of PELA to fabricate both the front junction and back surface field (BSF) would cost approximately 35 cents per peak watt (Wp), compared to a cost of 15 cents/Wp for diffusion, aluminum BSF and an extra cleaning step in the baseline process. The cost advantage of the PELA process depends on improving the average cell efficiency from 14% to 16%, which would lower the overall cost of the module by about 15 cents/Wp. An optimized PELA process compatible with commercial production is to be developed, and increased cell efficiency with sufficient product for adequate statistical analysis demonstrated. An excimer laser annealing station was set-up and made operational. The first experiment used 248 nm radiation to anneal phosphorus implants in polished and texture-etched silicon.

[Descriptive study of the costs of diagnosis and treatment of cutaneous melanoma].

PubMed

Almazán-Fernández, F M; Serrano-Ortega, S; Moreno-Villalonga, J J

2009-11-01

Every year, health expenditure in Spain increases and, with it, the resources dedicated to cancer treatment. Cutaneous melanoma is the skin cancer with the highest morbidity and mortality. We performed a descriptive study of the costs, based on a theoretical model, to determine the healthcare expenditure for patients with cutaneous melanoma; the objective was to define the overall costs (direct and indirect) of the diagnostic and treatment process of cutaneous melanoma, divided into different stages or diagnostic-therapeutic steps, and the possible variations in these costs. For this purpose, we used the Andalusian analytical accountancy program of hospitals and districts (COAN-hyd) and the total costs module of the COAN for 2007, applied to the protocol we use in the melanoma unit of our hospital. The most important conclusions were that the greatest health care expenditure was observed inpatients with more advanced melanomas, with a poor prognosis. Management of the diagnostic-therapeutic process by dermatologists, the appropriate use of complementary tests, and operations performed by dermatologists reduce costs.

Optimal design of reverse osmosis module networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maskan, F.; Wiley, D.E.; Johnston, L.P.M.

2000-05-01

The structure of individual reverse osmosis modules, the configuration of the module network, and the operating conditions were optimized for seawater and brackish water desalination. The system model included simple mathematical equations to predict the performance of the reverse osmosis modules. The optimization problem was formulated as a constrained multivariable nonlinear optimization. The objective function was the annual profit for the system, consisting of the profit obtained from the permeate, capital cost for the process units, and operating costs associated with energy consumption and maintenance. Optimization of several dual-stage reverse osmosis systems were investigated and compared. It was found thatmore » optimal network designs are the ones that produce the most permeate. It may be possible to achieve economic improvements by refining current membrane module designs and their operating pressures.« less

Toward a low-cost, low-power, low-complexity DAC-based multilevel (M-ary QAM) coherent transmitter using compact linear optical field modulator

NASA Astrophysics Data System (ADS)

Dingel, Benjamin

2017-01-01

In this invited paper, we summarize the current developments in linear optical field modulators (LOFMs) for coherent multilevel optical transmitters. Our focus is the presentation of a new, novel LOFM design that provides beneficial and necessary features such as lowest hardware component counts, lowered insertion loss, smaller RF power consumption, smaller footprint, simple structure, and lowered cost. We refer to this modulator as called Double-Pass LOFM (DP-LOFM) that becomes the building block for high-performance, linear Dual-Polarization, In-Phase- Quadrature-Phase (DP-IQ) modulator. We analyze its performance in term of slope linearity, and present one of its unique feature -- a built-in compensation functionality that no other linear modulators possessed till now.

[Development and application of a medical device maintenance information platform based on BS architecture].

PubMed

Liu, Shenglin; Zhang, Xutian; Wang, Guohong; Zhang, Qiang

2012-03-01

Based on specified demands on medical devices maintenance for clinical engineers and Browser/Server architecture technology, a medical device maintenance information platform was developed, which implemented the following modules such as repair, preventive maintenance, accessories management, training, document, system management and regional cooperation. The characteristics of this system were summarized and application in increase of repair efficiency, improvement of preventive maintenance and cost control was introduced. The application of this platform increases medical device maintenance service level.

Digital services using quadrature amplitude modulation (QAM) over CATV analog DWDM system

NASA Astrophysics Data System (ADS)

Yeh, JengRong; Selker, Mark D.; Trail, J.; Piehler, David; Levi, Israel

2000-04-01

Dense Wavelength Division Multiplexing (DWDM) has recently gained great popularity as it provides a cost effective way to increase the transmission capacity of the existing fiber cable plant. For a long time, Dense WDM was exclusively used for baseband digital applications, predominantly in terrestrial long haul networks and in some cases in metropolitan and enterprise networks. Recently, the performance of DWDM components and frequency-stabilized lasers has substantially improved while the costs have down significantly. This makes a variety of new optical network architectures economically viable. The first commercial 8- wavelength DWDM system designed for Hybrid Fiber Coax networks was reported in 1998. This type of DWDM system utilizes Sub-Carrier Multiplexing (SCM) of Quadrature Amplitude Modulated (QAM) signals to transport IP data digital video broadcast and Video on Demand on ITU grid lightwave carriers. The ability of DWDM to provide scalable transmission capacity in the optical layer with SCM granularity is now considered by many to be the most promising technology for future transport and distribution of broadband multimedia services.

On the Path to SunShot - Emerging Opportunities and Challenges in U.S. Solar Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chung, Donald; Horowitz, Kelsey; Kurup, Parthiv

Innovation-driven cost and performance improvements, along with strong projected solar demand in the United States and across the Americas, could increase the attractiveness of U.S.-based solar manufacturing (see Chung et al. 2016). Although improvements to standard PV modules have produced deep cost reductions over the past 5 years, the returns on such incremental improvements appear to be diminishing, and more dramatic innovations in module design and manufacturing are required to continue along the path of rapid progress. At the same time, major opportunities exist for innovation to unlock the potential of CSP technologies. This need for innovation could benefit U.S.more » PV and CSP manufacturers. The United States has been rated one of the world’s most competitive and innovative countries as well as one of the best locations for PV manufacturing. It is a global leader in PV and CSP R&D and patent production, and U.S. PV manufacturers are already pursuing highly differentiated innovations.« less

Preface

NASA Astrophysics Data System (ADS)

Zhuge, Qunbi; Chen, Xi

2018-02-01

Global IP traffic is predicted to increase nearly threefold over the next 5 years, driven by emerging high-bandwidth-demanding applications, such as cloud computing, 5G wireless, high-definition video streaming, and virtual reality. This results in a continuously increasing demand on the capacity of backbone optical networks. During the past decade, advanced digital signal processing (DSP), modulation formats, and forward error correction (FEC) were commercially realized to exploit the capacity potential of long-haul fiber channels, and have increased per channel data rate from 10 Gb/s to 400 Gb/s. DSP has played a crucial role in coherent transceivers to accommodate channel impairments including chromatic dispersion (CD), polarization mode dispersion (PMD), laser phase noise, fiber nonlinearities, clock jitter, and so forth. The advance of DSP has also enabled innovations in modulation formats to increase spectral efficiency, improve linear/nonlinear noise tolerance, and realize flexible bandwidth. Moving forward to next generation 1 Tb/s systems on conventional single mode fiber (SMF) platform, more innovations in DSP techniques are needed to further reduce cost per bit, increase network efficiency, and close the gap to the Shannon limit. To further increase capacity per fiber, spatial-division multiplexing (SDM) systems can be used. DSP techniques such as advanced channel equalization methods and distortion compensation can help SDM systems to achieve higher system capacity. In the area of short-reach transmission, the rapid increase of data center network traffic has driven the development of optical technologies for both intra- and inter-data center interconnects (DCI). In particular, DSP has been exploited in intensity-modulation direct detection (IM/DD) systems to realize 400 Gb/s pluggable optical transceivers. In addition, multi-dimensional direct detection modulation schemes are being investigated to increase the data rate per wavelength targeting 1 Tb/s interface.

Cost-effectiveness of modern radiotherapy techniques in locally advanced pancreatic cancer.

PubMed

Murphy, James D; Chang, Daniel T; Abelson, Jon; Daly, Megan E; Yeung, Heidi N; Nelson, Lorene M; Koong, Albert C

2012-02-15

Radiotherapy may improve the outcome of patients with pancreatic cancer but at an increased cost. In this study, the authors evaluated the cost-effectiveness of modern radiotherapy techniques in the treatment of locally advanced pancreatic cancer. A Markov decision-analytic model was constructed to compare the cost-effectiveness of 4 treatment regimens: gemcitabine alone, gemcitabine plus conventional radiotherapy, gemcitabine plus intensity-modulated radiotherapy (IMRT); and gemcitabine with stereotactic body radiotherapy (SBRT). Patients transitioned between the following 5 health states: stable disease, local progression, distant failure, local and distant failure, and death. Health utility tolls were assessed for radiotherapy and chemotherapy treatments and for radiation toxicity. SBRT increased life expectancy by 0.20 quality-adjusted life years (QALY) at an increased cost of $13,700 compared with gemcitabine alone (incremental cost-effectiveness ratio [ICER] = $69,500 per QALY). SBRT was more effective and less costly than conventional radiotherapy and IMRT. An analysis that excluded SBRT demonstrated that conventional radiotherapy had an ICER of $126,800 per QALY compared with gemcitabine alone, and IMRT had an ICER of $1,584,100 per QALY compared with conventional radiotherapy. A probabilistic sensitivity analysis demonstrated that the probability of cost-effectiveness at a willingness to pay of $50,000 per QALY was 78% for gemcitabine alone, 21% for SBRT, 1.4% for conventional radiotherapy, and 0.01% for IMRT. At a willingness to pay of $200,000 per QALY, the probability of cost-effectiveness was 73% for SBRT, 20% for conventional radiotherapy, 7% for gemcitabine alone, and 0.7% for IMRT. The current results indicated that IMRT in locally advanced pancreatic cancer exceeds what society considers cost-effective. In contrast, combining gemcitabine with SBRT increased clinical effectiveness beyond that of gemcitabine alone at a cost potentially acceptable by today's standards. Copyright © 2011 American Cancer Society.

Reusable Reentry Satellite (RRS) system design study: System cost estimates document

NASA Technical Reports Server (NTRS)

1991-01-01

The Reusable Reentry Satellite (RRS) program was initiated to provide life science investigators relatively inexpensive, frequent access to space for extended periods of time with eventual satellite recovery on earth. The RRS will provide an on-orbit laboratory for research on biological and material processes, be launched from a number of expendable launch vehicles, and operate in Low-Altitude Earth Orbit (LEO) as a free-flying unmanned laboratory. SAIC's design will provide independent atmospheric reentry and soft landing in the continental U.S., orbit for a maximum of 60 days, and will sustain three flights per year for 10 years. The Reusable Reentry Vehicle (RRV) will be 3-axis stabilized with artificial gravity up to 1.5g's, be rugged and easily maintainable, and have a modular design to accommodate a satellite bus and separate modular payloads (e.g., rodent module, general biological module, ESA microgravity botany facility, general botany module). The purpose of this System Cost Estimate Document is to provide a Life Cycle Cost Estimate (LCCE) for a NASA RRS Program using SAIC's RRS design. The estimate includes development, procurement, and 10 years of operations and support (O&S) costs for NASA's RRS program. The estimate does not include costs for other agencies which may track or interface with the RRS program (e.g., Air Force tracking agencies or individual RRS experimenters involved with special payload modules (PM's)). The life cycle cost estimate extends over the 10 year operation and support period FY99-2008.

Design and implement of pack filter module base on embedded firewall

NASA Astrophysics Data System (ADS)

Tian, Libo; Wang, Chen; Yang, Shunbo

2011-10-01

In the traditional security solution conditions, software firewall cannot intercept and respond the invasion before being attacked. And because of the high cost, the hardware firewall does not apply to the security strategy of the end nodes, so we have designed a kind of solution of embedded firewall with hardware and software. With ARM embedding Linux operating system, we have designed packet filter module and intrusion detection module to implement the basic function of firewall. Experiments and results show that that firewall has the advantages of low cost, high processing speed, high safety and the application of the computer terminals. This paper focuses on packet filtering module design and implementation.

Is Hand Selection Modulated by Cognitive-perceptual Load?

PubMed

Liang, Jiali; Wilkinson, Krista; Sainburg, Robert L

2018-01-15

Previous studies proposed that selecting which hand to use for a reaching task appears to be modulated by a factor described as "task difficulty". However, what features of a task might contribute to greater or lesser "difficulty" in the context of hand selection decisions has yet to be determined. There has been evidence that biomechanical and kinematic factors such as movement smoothness and work can predict patterns of selection across the workspace, suggesting a role of predictive cost analysis in hand-selection. We hypothesize that this type of prediction for hand-selection should recruit substantial cognitive resources and thus should be influenced by cognitive-perceptual loading. We test this hypothesis by assessing the role of cognitive-perceptual loading on hand selection decisions, using a visual search task that presents different levels of difficulty (cognitive-perceptual load), as established in previous studies on overall response time and efficiency of visual search. Although the data are necessarily preliminary due to small sample size, our data suggested an influence of cognitive-perceptual load on hand selection, such that the dominant hand was selected more frequently as cognitive load increased. Interestingly, cognitive-perceptual loading also increased cross-midline reaches with both hands. Because crossing midline is more costly in terms of kinematic and kinetic factors, our findings suggest that cognitive processes are normally engaged to avoid costly actions, and that the choice not-to-cross midline requires cognitive resources. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

DPSK-3ASK transmission optimization by adapting modulation levels

NASA Astrophysics Data System (ADS)

Eiselt, Michael H.; Teipen, Brian T.

2008-11-01

For metro and regional 100-Gbps transmission, a transparent channel reach of 500-600 km is required and a 100-GHz channel grid is typically used. For these applications, a cost effective modulation format is introduced which can make use of electronic components designed for the already established 40-Gbps market, bypassing the requirements for novel electronic developments and therefore reducing the component cost. With this DPSK-3ASK modulation format, five information bits are transmitted in two consecutive symbols, leading to a symbol rate of 45 Gbaud, including overhead for framing and FEC. To minimize hardware requirements and to create a cost-effective solution, a single Mach-Zehnder modulator can be used to create the optical DPSK-3ASK signal after combining the phase and amplitude modulation signals into a 6-level modulator drive voltage. In this paper, it is demonstrated by numerical simulations that these voltage levels can be modified to adapt to varying signal distortions and thereby yield improved transmission performance. It is shown that by dynamically modifying the modulation levels based on the channel performance, dynamic signal impairments such as the non-linear effects from varying power levels, changes in chromatic dispersion, or varying PMD levels can be mitigated. Error-free performance (with FEC) can be obtained with 24 dB OSNR and 7ps DGD for a 112-Gbps (45-Gbaud) optical signal.

Optics-based approach to thermal management of photovoltaics: Selective-spectral and radiative cooling

DOE PAGES

Sun, Xingshu; Silverman, Timothy J.; Zhou, Zhiguang; ...

2017-01-20

For commercial one-sun solar modules, up to 80% of the incoming sunlight may be dissipated as heat, potentially raising the temperature 20-30 °C higher than the ambient. In the long term, extreme self-heating erodes efficiency and shortens lifetime, thereby dramatically reducing the total energy output. Therefore, it is critically important to develop effective and practical (and preferably passive) cooling methods to reduce operating temperature of photovoltaic (PV) modules. In this paper, we explore two fundamental (but often overlooked) origins of PV self-heating, namely, sub-bandgap absorption and imperfect thermal radiation. The analysis suggests that we redesign the optical properties of themore » solar module to eliminate parasitic absorption (selective-spectral cooling) and enhance thermal emission (radiative cooling). Comprehensive opto-electro-thermal simulation shows that the proposed techniques would cool one-sun terrestrial solar modules up to 10 °C. As a result, this self-cooling would substantially extend the lifetime for solar modules, with corresponding increase in energy yields and reduced levelized cost of electricity.« less

Technology Benefit Estimator (T/BEST): User's Manual

NASA Technical Reports Server (NTRS)

Generazio, Edward R.; Chamis, Christos C.; Abumeri, Galib

1994-01-01

The Technology Benefit Estimator (T/BEST) system is a formal method to assess advanced technologies and quantify the benefit contributions for prioritization. T/BEST may be used to provide guidelines to identify and prioritize high payoff research areas, help manage research and limited resources, show the link between advanced concepts and the bottom line, i.e., accrued benefit and value, and to communicate credibly the benefits of research. The T/BEST software computer program is specifically designed to estimating benefits, and benefit sensitivities, of introducing new technologies into existing propulsion systems. Key engine cycle, structural, fluid, mission and cost analysis modules are used to provide a framework for interfacing with advanced technologies. An open-ended, modular approach is used to allow for modification and addition of both key and advanced technology modules. T/BEST has a hierarchical framework that yields varying levels of benefit estimation accuracy that are dependent on the degree of input detail available. This hierarchical feature permits rapid estimation of technology benefits even when the technology is at the conceptual stage. As knowledge of the technology details increases the accuracy of the benefit analysis increases. Included in T/BEST's framework are correlations developed from a statistical data base that is relied upon if there is insufficient information given in a particular area, e.g., fuel capacity or aircraft landing weight. Statistical predictions are not required if these data are specified in the mission requirements. The engine cycle, structural fluid, cost, noise, and emissions analyses interact with the default or user material and component libraries to yield estimates of specific global benefits: range, speed, thrust, capacity, component life, noise, emissions, specific fuel consumption, component and engine weights, pre-certification test, mission performance engine cost, direct operating cost, life cycle cost, manufacturing cost, development cost, risk, and development time. Currently, T/BEST operates on stand-alone or networked workstations, and uses a UNIX shell or script to control the operation of interfaced FORTRAN based analyses. T/BEST's interface structure works equally well with non-FORTRAN or mixed software analysis. This interface structure is designed to maintain the integrity of the expert's analyses by interfacing with expert's existing input and output files. Parameter input and output data (e.g., number of blades, hub diameters, etc.) are passed via T/BEST's neutral file, while copious data (e.g., finite element models, profiles, etc.) are passed via file pointers that point to the expert's analyses output files. In order to make the communications between the T/BEST's neutral file and attached analyses codes simple, only two software commands, PUT and GET, are required. This simplicity permits easy access to all input and output variables contained within the neutral file. Both public domain and proprietary analyses codes may be attached with a minimal amount of effort, while maintaining full data and analysis integrity, and security. T/BESt's sotware framework, status, beginner-to-expert operation, interface architecture, analysis module addition, and key analysis modules are discussed. Representative examples of T/BEST benefit analyses are shown.

Technology Benefit Estimator (T/BEST): User's manual

NASA Astrophysics Data System (ADS)

Generazio, Edward R.; Chamis, Christos C.; Abumeri, Galib

1994-12-01

The Technology Benefit Estimator (T/BEST) system is a formal method to assess advanced technologies and quantify the benefit contributions for prioritization. T/BEST may be used to provide guidelines to identify and prioritize high payoff research areas, help manage research and limited resources, show the link between advanced concepts and the bottom line, i.e., accrued benefit and value, and to communicate credibly the benefits of research. The T/BEST software computer program is specifically designed to estimating benefits, and benefit sensitivities, of introducing new technologies into existing propulsion systems. Key engine cycle, structural, fluid, mission and cost analysis modules are used to provide a framework for interfacing with advanced technologies. An open-ended, modular approach is used to allow for modification and addition of both key and advanced technology modules. T/BEST has a hierarchical framework that yields varying levels of benefit estimation accuracy that are dependent on the degree of input detail available. This hierarchical feature permits rapid estimation of technology benefits even when the technology is at the conceptual stage. As knowledge of the technology details increases the accuracy of the benefit analysis increases. Included in T/BEST's framework are correlations developed from a statistical data base that is relied upon if there is insufficient information given in a particular area, e.g., fuel capacity or aircraft landing weight. Statistical predictions are not required if these data are specified in the mission requirements. The engine cycle, structural fluid, cost, noise, and emissions analyses interact with the default or user material and component libraries to yield estimates of specific global benefits: range, speed, thrust, capacity, component life, noise, emissions, specific fuel consumption, component and engine weights, pre-certification test, mission performance engine cost, direct operating cost, life cycle cost, manufacturing cost, development cost, risk, and development time. Currently, T/BEST operates on stand-alone or networked workstations, and uses a UNIX shell or script to control the operation of interfaced FORTRAN based analyses. T/BEST's interface structure works equally well with non-FORTRAN or mixed software analysis. This interface structure is designed to maintain the integrity of the expert's analyses by interfacing with expert's existing input and output files. Parameter input and output data (e.g., number of blades, hub diameters, etc.) are passed via T/BEST's neutral file, while copious data (e.g., finite element models, profiles, etc.) are passed via file pointers that point to the expert's analyses output files. In order to make the communications between the T/BEST's neutral file and attached analyses codes simple, only two software commands, PUT and GET, are required. This simplicity permits easy access to all input and output variables contained within the neutral file. Both public domain and proprietary analyses codes may be attached with a minimal amount of effort, while maintaining full data and analysis integrity, and security.

Economic viability of thin-film tandem solar modules in the United States

NASA Astrophysics Data System (ADS)

Sofia, Sarah E.; Mailoa, Jonathan P.; Weiss, Dirk N.; Stanbery, Billy J.; Buonassisi, Tonio; Peters, I. Marius

2018-05-01

Tandem solar cells are more efficient but more expensive per unit area than established single-junction (SJ) solar cells. To understand when specific tandem architectures should be utilized, we evaluate the cost-effectiveness of different II-VI-based thin-film tandem solar cells and compare them to the SJ subcells. Levelized cost of electricity (LCOE) and energy yield are calculated for four technologies: industrial cadmium telluride and copper indium gallium selenide, and their hypothetical two-terminal (series-connected subcells) and four-terminal (electrically independent subcells) tandems, assuming record SJ quality subcells. Different climatic conditions and scales (residential and utility scale) are considered. We show that, for US residential systems with current balance-of-system costs, the four-terminal tandem has the lowest LCOE because of its superior energy yield, even though it has the highest US per watt (US W-1) module cost. For utility-scale systems, the lowest LCOE architecture is the cadmium telluride single junction, the lowest US W-1 module. The two-terminal tandem requires decreased subcell absorber costs to reach competitiveness over the four-terminal one.

Getting the Right Staff. Personnel Management Module. Operational Management Programme. Increasing Opportunities for Supervisors and Managers.

ERIC Educational Resources Information Center

Goddard, Tessa; Murray, Jennifer

This self-instructional unit for supervisors and managers in the British hotel and catering industry contains information on all the important stages in the process of recruiting staff. The document begins with an introduction and advice on how to use the unit. Five sections cover the following topics: (1) the cost of employment; (2) planning for…

Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun

NASA Astrophysics Data System (ADS)

Kii, Toshiteru; Nakai, Yoko; Fukui, Toshio; Zen, Heishun; Kusukame, Kohichi; Okawachi, Norihito; Nakano, Masatsugu; Masuda, Kai; Ohgaki, Hideaki; Yoshikawa, Kiyoshi; Yamazaki, Tetsuo

2007-01-01

Energy degradation due to back-bombardment effect is quite serious to produce high-brightness electron beam with long macro-pulse with thermionic rf gun. To avoid the back-bombardment problem, a laser photo cathode is used at many FEL facilities, but usually it costs high and not easy to operate. Thus we have studied long pulse operation of the rf gun with thermionic cathode, which is inexpensive and easy to operate compared to the photocathode rf gun. In this work, to reduce the energy degradation, we controlled input rf power amplitude by controlling pulse forming network of the power modulator for klystron. We have successfully increased the pulse duration up to 4 μs by increasing the rf power from 7.8 MW to 8.5 MW during the macro pulse.

Contextual control over task-set retrieval.

PubMed

Crump, Matthew J C; Logan, Gordon D

2010-11-01

Contextual cues signaling task likelihood or the likelihood of task repetition are known to modulate the size of switch costs. We follow up on the finding by Leboe, Wong, Crump, and Stobbe (2008) that location cues predictive of the proportion of switch or repeat trials modulate switch costs. Their design employed one cue per task, whereas our experiment employed two cues per task, which allowed separate assessment of modulations to the cue-repetition benefit, a measure of lower level cue-encoding processes, and to the task-alternation cost, a measure of higher level processes representing task-set information. We demonstrate that location information predictive of switch proportion modulates performance at the level of task-set representations. Furthermore, we demonstrate that contextual control occurs even when subjects are unaware of the associations between context and switch likelihood. We discuss the notion that contextual information provides rapid, unconscious control over the extent to which prior task-set representations are retrieved in the service of guiding online performance.

Reliability and performance experience with flat-plate photovoltaic modules

NASA Technical Reports Server (NTRS)

Ross, R. G., Jr.

1982-01-01

Statistical models developed to define the most likely sources of photovoltaic (PV) array failures and the optimum method of allowing for the defects in order to achieve a 20 yr lifetime with acceptable performance degradation are summarized. Significant parameters were the cost of energy, annual power output, initial cost, replacement cost, rate of module replacement, the discount rate, and the plant lifetime. Acceptable degradation allocations were calculated to be 0.0001 cell failures/yr, 0.005 module failures/yr, 0.05 power loss/yr, a 0.01 rate of power loss/yr, and a 25 yr module wear-out length. Circuit redundancy techniques were determined to offset cell failures using fault tolerant designs such as series/parallel and bypass diode arrangements. Screening processes have been devised to eliminate cells that will crack in operation, and multiple electrical contacts at each cell compensate for the cells which escape the screening test and then crack when installed. The 20 yr array lifetime is expected to be achieved in the near-term.

Development of a Grid-Independent Geos-Chem Chemical Transport Model (v9-02) as an Atmospheric Chemistry Module for Earth System Models

NASA Technical Reports Server (NTRS)

Long, M. S.; Yantosca, R.; Nielsen, J. E; Keller, C. A.; Da Silva, A.; Sulprizio, M. P.; Pawson, S.; Jacob, D. J.

2015-01-01

The GEOS-Chem global chemical transport model (CTM), used by a large atmospheric chemistry research community, has been re-engineered to also serve as an atmospheric chemistry module for Earth system models (ESMs). This was done using an Earth System Modeling Framework (ESMF) interface that operates independently of the GEOSChem scientific code, permitting the exact same GEOSChem code to be used as an ESM module or as a standalone CTM. In this manner, the continual stream of updates contributed by the CTM user community is automatically passed on to the ESM module, which remains state of science and referenced to the latest version of the standard GEOS-Chem CTM. A major step in this re-engineering was to make GEOS-Chem grid independent, i.e., capable of using any geophysical grid specified at run time. GEOS-Chem data sockets were also created for communication between modules and with external ESM code. The grid-independent, ESMF-compatible GEOS-Chem is now the standard version of the GEOS-Chem CTM. It has been implemented as an atmospheric chemistry module into the NASA GEOS- 5 ESM. The coupled GEOS-5-GEOS-Chem system was tested for scalability and performance with a tropospheric oxidant-aerosol simulation (120 coupled species, 66 transported tracers) using 48-240 cores and message-passing interface (MPI) distributed-memory parallelization. Numerical experiments demonstrate that the GEOS-Chem chemistry module scales efficiently for the number of cores tested, with no degradation as the number of cores increases. Although inclusion of atmospheric chemistry in ESMs is computationally expensive, the excellent scalability of the chemistry module means that the relative cost goes down with increasing number of cores in a massively parallel environment.

A Cost Analysis of the American Board of Internal Medicine's Maintenance-of-Certification Program.

PubMed

Sandhu, Alexander T; Dudley, R Adams; Kazi, Dhruv S

2015-09-15

In 2014, the American Board of Internal Medicine (ABIM) substantially increased the requirements and fees for its maintenance-of-certification (MOC) program. Faced with mounting criticism, the ABIM suspended certain content requirements in February 2015 but retained the increased fees and number of modules. An objective appraisal of the cost of MOC would help inform upcoming consultations about MOC reform. To estimate the total cost of the 2015 version of the MOC program ("2015 MOC") and the incremental cost relative to the 2013 version ("2013 MOC"). Decision analytic model. Published literature. All ABIM-certified U.S. physicians. 10 years (2015 to 2024). Societal. 2015 MOC. Testing costs (ABIM fees) and time costs (monetary value of physician time). Internists will incur an average of $23 607 (95% CI, $5380 to $66 383) in MOC costs over 10 years, ranging from $16 725 for general internists to $40 495 for hematologists-oncologists. Time costs account for 90% of MOC costs. Cumulatively, 2015 MOC will cost $5.7 billion over 10 years, $1.2 billion more than 2013 MOC. This includes $5.1 billion in time costs (resulting from 32.7 million physician-hours spent on MOC) and $561 million in testing costs. Costs are sensitive to time spent on MOC and MOC credits obtainable from current continuing education activities. Precise estimates of time required for MOC are not available. The ABIM MOC program will generate considerable costs, predominantly due to demands on physician time. A rigorous evaluation of its effect on clinical and economic outcomes is warranted to balance potential gains in health care quality and efficiency against the high costs identified in this study. University of California, San Francisco, and the U.S. Department of Veterans Affairs.

Encapsulant selection and durability testing experience

NASA Technical Reports Server (NTRS)

Cuddihy, E. F.

1985-01-01

The Flat Plate Solar Array Project (FSA) has established technically challenging cost and service life goals for photovoltaic modules. These goals are a cost of $70 sq m and an expected 30 years of service life in an outdoor weathering environment. out of the cost goal, $14 sq m is allocated for encapsulation materials, which includes the cost of a structural panel. At FSA's inception in 1975, the cumulative cost of encapsulation materials in popular use, such as room temperature vulcanized (RTV) silicones, aluminum panels, etc., greatly exceeded $14/sq m. Accordingly, it became necessary to identify and/or develop new materials and new material technologies to achieve the goals. Many of these new materials are low cost polymers that satisfy module engineering and encapsulation processing requirements but unfortunately are not intrinsically weather stable. This necessitates identifying lifetime and/or weathering deficiencies inherent in these low cost materials and developing specific approaches to enhancing weather stability.

Impact of Balance Of System (BOS) costs on photovoltaic power systems

NASA Technical Reports Server (NTRS)

Hein, G. F.; Cusick, J. P.; Poley, W. A.

1978-01-01

The Department of Energy has developed a program to effect a large reduction in the price of photovoltaic modules, with significant progress already achieved toward the 1986 goal of 50 cents/watt (1975 dollars). Remaining elements of a P/V power system (structure, battery storage, regulation, control, and wiring) are also significant cost items. The costs of these remaining elements are commonly referred to as Balance-of-System (BOS) costs. The BOS costs are less well defined and documented than module costs. The Lewis Research Center (LeRC) in 1976/77 and with two village power experiments that will be installed in 1978. The costs were divided into five categories and analyzed. A regression analysis was performed to determine correlations of BOS Costs per peak watt, with power size for these photovoltaic systems. The statistical relationship may be used for flat-plate, DC systems ranging from 100 to 4,000 peak watts. A survey of suppliers was conducted for comparison with the predicted BOS cost relationship.

Experimental measurements of a prototype high-concentration Fresnel lens and sun-tracking method for photovoltaic panel's efficiency enhancement

NASA Astrophysics Data System (ADS)

Rajaee, Meraj; Ghorashi, Seyed Mohamad Bagher

2015-08-01

Concentrator photovoltaic modules are a promising technology for highly efficient solar energy conversion. This system presents several advantages due to additional degrees of freedom that has been provided by the spectral separation such as cost and mass reduction, increase in the incident solar flux on PV cells and performances. This paper has proposed a unique photovoltaic solar cell system that consists of semi-Fresnel lens convergent structure and a novel two axis sun tracking module to enhance the efficiency of solar cell by using less cell area and energy losses. The grooves of this lens are calculated according to the refraction and convergent angles of the light easy for perpendicular incidence angle. The update time interval during tracking causes misalignment of the lens' optical axis versus the sunrays. Then an inventive sun-tracking method is introduced to adjust the module so that the incident rays are always perpendicular to the module's surface. As a result, all rays will be refracted with the predetermined angles. This way the focus area is reduced and smaller cells can be used. We also mentioned different module connections in order to provide compensation method during losses, for networks and power systems. Experimental results show that using semi-Fresnel lens, along with the sun-tracking method increases the efficiency of PV panel.

Cost Study of Educational Media Systems and Their Equipment Components. Volume III, A Supplementary Report: Computer Assisted Instruction. Final Report.

ERIC Educational Resources Information Center

General Learning Corp., Washington, DC.

The COST-ED model (Costs of Schools, Training, and Education) of the instructional process encourages the recognition of management alternatives and potential cost-savings. It is used to calculate the minimum cost of performing specified instructional tasks. COST-ED components are presented as cost modules in a flowchart format for manpower,…

Analysis of the Effect of Module Thickness Reduction on Thermoelectric Generator Output

NASA Astrophysics Data System (ADS)

Brito, F. P.; Figueiredo, L.; Rocha, L. A.; Cruz, A. P.; Goncalves, L. M.; Martins, J.; Hall, M. J.

2016-03-01

Conventional thermoelectric generators (TEGs) used in applications such as exhaust heat recovery are typically limited in terms of power density due to their low efficiency. Additionally, they are generally costly due to the bulk use of rare-earth elements such as tellurium. If less material could be used for the same output, then the power density and the overall cost per kilowatt (kW) of electricity produced could drop significantly, making TEGs a more attractive solution for energy harvesting of waste heat. The present work assesses the effect of reducing the amount of thermoelectric (TE) material used (namely by reducing the module thickness) on the electrical output of conventional bismuth telluride TEGs. Commercial simulation packages (ANSYS CFX and thermal-electric) and bespoke models were used to simulate the TEGs at various degrees of detail. Effects such as variation of the thermal and electrical contact resistance and the component thickness and the effect of using an element supporting matrix (e.g., eggcrate) instead of having air conduction in void areas have been assessed. It was found that indeed it is possible to reduce the use of bulk TE material while retaining power output levels equivalent to thicker modules. However, effects such as thermal contact resistance were found to become increasingly important as the active TE material thickness was decreased.

Bringing together integration technologies in GaAs, InP and Si to deliver low-cost high performance DWDM optoelectronic components and solutions

NASA Astrophysics Data System (ADS)

Carter, Andrew C.; Wale, Michael J.; Simmons, T.; Whitbread, Neil; Asghari, M.

2003-06-01

A key attribute emerging in the optoelectronic component supply industry is the ability to deliver 'solution level' products rather than discrete optical components to equipment manufacturers. This approach is primarily aimed at reducing cost for the equipment manufacturer both in engineering and assembly. Such 'solutions' must be designed to be cost effective - offering costs substantially below discrete components - and must be compatible with subcontract board manufacture without the traditional and expensive skills of fibre handling, splicing and management. Examples of 'solutions' in this context may be the core of a multifunctional OADM or a DWDM laser transmitter subsystem, with modulation, wavelength and power management all included in a simple to use module. Essential to the cost effective production of such solutions is a high degree of optical/optoelectronic integration. Co-packaging of discrete components and electronics into modules will not deliver the cost reduction demanded. At Bookham Technology we have brought together what we believe to be the three key integration technologies - InP for monolithic tunable sources, GaAs for high performance integrated modulation and ASOC for smart passives and hybrid platforms - which can deliver this cost reduction, together with performance enhancement, over a wide range of applications. In the paper we will demonstrate and compare our above integration approaches with the competing alternatives and seek to show how the power of integration is finally being harnessed in optoelectronics, delivering radical cost reduction as well as enabling system concepts virtually impossible to achieve with discrete components. In the paper we will demonstrate and compare our above integration approaches with the competing alternatives and seek to show how the power of integration is finally being harnessed in optoelectronics, delivering radical cost reduction as well as enabling system concepts virtually impossible to achieve with discrete components.

Cost-effectiveness of sequenced treatment of rheumatoid arthritis with targeted immune modulators.

PubMed

Jansen, Jeroen P; Incerti, Devin; Mutebi, Alex; Peneva, Desi; MacEwan, Joanna P; Stolshek, Bradley; Kaur, Primal; Gharaibeh, Mahdi; Strand, Vibeke

2017-07-01

To determine the cost-effectiveness of treatment sequences of biologic disease-modifying anti-rheumatic drugs or Janus kinase/STAT pathway inhibitors (collectively referred to as bDMARDs) vs conventional DMARDs (cDMARDs) from the US societal perspective for treatment of patients with moderately to severely active rheumatoid arthritis (RA) with inadequate responses to cDMARDs. An individual patient simulation model was developed that assesses the impact of treatments on disease based on clinical trial data and real-world evidence. Treatment strategies included sequences starting with etanercept, adalimumab, certolizumab, or abatacept. Each of these treatment strategies was compared with cDMARDs. Incremental cost, incremental quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) were calculated for each treatment sequence relative to cDMARDs. The cost-effectiveness of each strategy was determined using a US willingness-to-pay (WTP) threshold of $150,000/QALY. For the base-case scenario, bDMARD treatment sequences were associated with greater treatment benefit (i.e. more QALYs), lower lost productivity costs, and greater treatment-related costs than cDMARDs. The expected ICERs for bDMARD sequences ranged from ∼$126,000 to $140,000 per QALY gained, which is below the US-specific WTP. Alternative scenarios examining the effects of homogeneous patients, dose increases, increased costs of hospitalization for severely physically impaired patients, and a lower baseline Health Assessment Questionnaire (HAQ) Disability Index score resulted in similar ICERs. bDMARD treatment sequences are cost-effective from a US societal perspective.

Solar photovoltaic systems

NASA Technical Reports Server (NTRS)

Forney, R. G.

1978-01-01

The Department of Energy's photovoltaic program is outlined. The main objective of the program is the development of low cost reliable terrestrial photovoltaic systems. A second objective is to foster widespread use of the system in residential, industrial and commercial application. The system is reviewed by examining each component; silicon solar cell, silicon solar cell modules, advanced development modules and power systems. Cost and applications of the system are discussed.

Crack detection on wind turbine blades in an operating environment using vibro-acoustic modulation technique

NASA Astrophysics Data System (ADS)

Kim, S.; Adams, D. E.; Sohn, H.

2013-01-01

As the wind power industry has grown rapidly in the recent decade, maintenance costs have become a significant concern. Due to the high repair costs for wind turbine blades, it is especially important to detect initial blade defects before they become structural failures leading to other potential failures in the tower or nacelle. This research presents a method of detecting cracks on wind turbine blades using the Vibo-Acoustic Modulation technique. Using Vibro-Acoustic Modulation, a crack detection test is conducted on a WHISPER 100 wind turbine in its operating environment. Wind turbines provide the ideal conditions in which to utilize Vibro-Acoustic Modulation because wind turbines experience large structural vibrations. The structural vibration of the wind turbine balde was used as a pumping signal and a PZT was used to generate the probing signal. Because the non-linear portion of the dynamic response is more sensitive to the presence of a crack than the environmental conditions or operating loads, the Vibro-Acoustic Modulation technique can provide a robust structural health monitoring approach for wind turbines. Structural health monitoring can significantly reduce maintenance costs when paired with predictive modeling to minimize unscheduled maintenance.

Disparate bilingual experiences modulate task-switching advantages: A diffusion-model analysis of the effects of interactional context on switch costs.

PubMed

Hartanto, Andree; Yang, Hwajin

2016-05-01

Drawing on the adaptive control hypothesis (Green & Abutalebi, 2013), we investigated whether bilinguals' disparate interactional contexts modulate task-switching performance. Fifty-eight bilinguals within the single-language context (SLC) and 75 bilinguals within the dual-language context (DLC) were compared in a typical task-switching paradigm. Given that DLC bilinguals switch between languages within the same context, while SLC bilinguals speak only one language in one environment and therefore rarely switch languages, we hypothesized that the two groups' stark difference in their interactional contexts of conversational exchanges would lead to differences in switch costs. As predicted, DLC bilinguals showed smaller switch costs than SLC bilinguals. Our diffusion-model analyses suggest that DLC bilinguals' benefits in switch costs are more likely driven by task-set reconfiguration than by proactive interference. Our findings underscore the modulating role of the interactional context of conversational exchanges in task switching. Copyright © 2016 Elsevier B.V. All rights reserved.

Optimization of A(2)O BNR processes using ASM and EAWAG Bio-P models: model performance.

PubMed

El Shorbagy, Walid E; Radif, Nawras N; Droste, Ronald L

2013-12-01

This paper presents the performance of an optimization model for a biological nutrient removal (BNR) system using the anaerobic-anoxic-oxic (A(2)O) process. The formulated model simulates removal of organics, nitrogen, and phosphorus using a reduced International Water Association (IWA) Activated Sludge Model #3 (ASM3) model and a Swiss Federal Institute for Environmental Science and Technology (EAWAG) Bio-P module. Optimal sizing is attained considering capital and operational costs. Process performance is evaluated against the effect of influent conditions, effluent limits, and selected parameters of various optimal solutions with the following results: an increase of influent temperature from 10 degrees C to 25 degrees C decreases the annual cost by about 8.5%, an increase of influent flow from 500 to 2500 m(3)/h triples the annual cost, the A(2)O BNR system is more sensitive to variations in influent ammonia than phosphorus concentration and the maximum growth rate of autotrophic biomass was the most sensitive kinetic parameter in the optimization model.

The development of a low-cost laser communication system for the classroom

NASA Astrophysics Data System (ADS)

Sparks, Robert T.; Pompea, Stephen M.; Walker, Constance E.

2007-06-01

Hands-On Optics (HOO) is a National Science Foundation funded program to bring optics education to underserved middle school students. We have developed the culminating module (Module 6) on laser communication. Students learn how lasers can be modulated to carry information. The main activity of this module is the construction of a low-cost laser communication system. The system can be built using parts readily available at a local electronics store for approximately US $60. The system can be used to transmit a person's voice or music from sources such as an mp3 player or radio over a distance of 350 feet. We will provide detailed plans on how to build the system in this paper.

Development and Characterization of a Small Spacecraft Electro-Optic Scanner for Free-Space Laser Communications

NASA Technical Reports Server (NTRS)

Davis, Scott; Lichter, Michael; Raible, Daniel

2016-01-01

Emergent data-intensive missions coupled with dramatic reductions in spacecraft size plus an increasing number of space-based missions necessitates new high performance, compact and low cost communications technology. Free space optical communications offer advantages including orders of magnitude increase for data rate performance, increased security, immunity to jamming and lack of frequency allocation requirements when compared with conventional radio frequency (RF) means. The spatial coherence and low divergence associated with the optical frequencies of laser communications lends themselves to superior performance, but this increased directionality also creates one of the primary technical challenges in establishing a laser communications link by repeatedly and reliably pointing the beam onto the receive aperture. Several solutions have emerged from wide angle (slow) mechanical articulation systems, fine (fast) steering mirrors and rotating prisms, inertial compensation gyros and vibration isolation cancellation systems, but each requires moving components and imparts a measured amount of burden on the host platform. The complexity, cost and size of current mechanically scanned solutions limits their platform applicability, and restricts the feasibility of deploying optical communications payloads on very compact spacecraft employing critical systems. A high speed, wide angle, non-mechanical solution is therefore desirable. The purpose of this work is to share the development, testing, and demonstration of a breadboard prototype electro-optic (EO) scanned laser-communication link (see Figure 1). This demonstration is a step toward realizing ultra-low Size, Weight and Power (SWaP) SmallSat/MicroSat EO non-mechanical laser beam steering modules for high bandwidth ( greater than Gbps) free-space data links operating in the 1550 nm wavelength bands. The elimination of all moving parts will dramatically reduce SWaP and cost, increase component lifetime and reliability, and simplify the system design of laser communication modules. This paper describes the target mission architectures and requirements (few cubic centimeters of volume, 10's of grams of weight with milliwatts of power) and design of the beam steering module. Laboratory metrology is used to determine the component performance including horizontal and vertical resolution (20urad) as a function of control voltage (see Figure 2), transition time (0.1-1ms), pointing repeatability and optic insertion loss. A test bed system demonstration, including a full laser communications link, is conducted. The capabilities of this new EO beam steerer provide an opportunity to dramatically improve space communications through increased utilization of laser technology on smaller platforms than were previously attainable.

Design, fabrication, test qualification and price analysis of a third generation solar cell module

NASA Technical Reports Server (NTRS)

1982-01-01

The design, fabrication, test, and qualification of a third generation intermediate load solar cell module are presented. A technical discussion of the detailed module design, preliminary design review, design modifications, and environmental testing are included. A standardized pricing system is utilized to establish the cost competitiveness of this module design.

Autism Tendencies and Psychosis Proneness Interactively Modulate Saliency Cost

PubMed Central

Abu-Akel, Ahmad; Apperly, Ian A.; Wood, Stephen J.; Hansen, Peter C.; Mevorach, Carmel

2017-01-01

Atypical responses to salient information are a candidate endophenotype for both autism and psychosis spectrum disorders. The present study investigated the costs and benefits of such atypicalities for saliency-based selection in a large cohort of neurotypical adults in whom both autism and psychosis expressions were assessed. Two experiments found that autism tendencies and psychosis proneness interactively modulated the cost incurred in the presence of a task-irrelevant salient distractor. Specifically, expressions of autism and psychosis had opposing effects on responses to salient information such that the benefits associated with high expressions for autism offset costs associated with high expressions for psychosis. The opposing influences observed on saliency cost may be driven by distinct attentional mechanisms that are differentially affected by expressions for autism and psychosis. PMID:27217269

Investigation of test methods, material properties and processes for solar cell encapsulants

NASA Technical Reports Server (NTRS)

Willis, P. B.; Baum, B.

1983-01-01

The goal of the program is to identify, test, evaluate and recommend encapsulation materials and processes for the fabrication of cost-effective and long life solar modules. Of the $18 (1948 $) per square meter allocated for the encapsulation components approximately 50% of the cost ($9/sq m) may be taken by the load bearing component. Due to the proportionally high cost of this element, lower costing materials were investigated. Wood based products were found to be the lowest costing structural materials for module construction, however, they require protection from rainwater and humidity in order to acquire dimensional stability. The cost of a wood product based substrate must, therefore, include raw material costs plus the cost of additional processing to impart hygroscopic inertness. This protection is provided by a two step, or split process in which a flexible laminate containing the cell string is prepared, first in a vacuum process and then adhesively attached with a back cover film to the hardboard in a subsequent step.

Highly Automated Module Production Incorporating Advanced Light Management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perelli-Minetti, Michael; Roof, Kyle

2015-08-11

The objective was to enable a high volume, cost effective solution for increasing the amount of light captured by PV modules through utilization of an advanced Light Re-directing Film and to follow a phased approach to develop and implement this new technology in order to achieve an expected power gain of up to 12 watts per module. Full size PV modules were manufactured using a new Light Redirecting Film (LRF) material applied to two different areas of PV modules in order to increase the amount of light captured by the modules. One configuration involved applying thin strips of LRF filmmore » over the tabbing ribbon on the cells in order to redirect the light that is normally absorbed by the tabbing ribbon to the active areas of the cells. A second configuration involved applying thin strips of LRF film over the white spaces between cells within a module in order to capture some of the light that is normally reflected from the white areas back through the front glass of the modules. Significant power increases of 1.4% (3.9 watts) and 1.0% (3.2 watts), respectively, compared to standard PV modules were measured under standard test conditions. The performance of PV modules with LRF applied to the tabbing ribbon was modeled. The results showed that the power increase provided by LRF depended greatly on the angle of incident light with the optimum performance only occurring when the light was within a narrow range of being perpendicular to the solar module. The modeling showed that most of the performance gain would be lost when the angle of incident light was greater than 28 degrees off axis. This effect made the orientation of modules with LRF applied to tabbing ribbons very important as modules mounted in “portrait” mode were predicted to provide little to no power gain from LRF under real world conditions. Based on these results, modules with LRF on tabbing ribbons would have to be mounted in “landscape” mode to realize a performance advantage. In addition, modeling showed that under diffuse lighting conditions such as when the sky is overcast, there would be no significant performance advantage for modules with LRF. Modules were sent to an outside contractor to measure the power performance under different angles of incident light in order to validate the modeling results. The measured data agreed very well with the modeling predictions and showed that the power gain for modules with LRF applied to tabbing ribbons was completely lost at an angle of 25 degrees off of perpendicular. At even larger angles, the power was lower than standard modules. From 35 degrees to 55 degrees off axis, the power loss was about 1.4% or equal to the power gain at the optimum condition of perfectly on-axis light.« less

Homing pigeons (Columba livia) modulate wingbeat characteristics as a function of route familiarity.

PubMed

Taylor, Lucy A; Portugal, Steven J; Biro, Dora

2017-08-15

Mechanisms of avian navigation have received considerable attention, but whether different navigational strategies are accompanied by different flight characteristics is unknown. Managing energy expenditure is critical for survival; therefore, understanding how flight characteristics, and hence energy allocation, potentially change with birds' familiarity with a navigational task could provide key insights into the costs of orientation. We addressed this question by examining changes in the wingbeat characteristics and airspeed of homing pigeons ( Columba livia ) as they learned a homing task. Twenty-one pigeons were released 20 times individually either 3.85 or 7.06 km from home. Birds were equipped with 5 Hz GPS trackers and 200 Hz tri-axial accelerometers. We found that, as the birds' route efficiency increased during the first six releases, their median peak-to-peak dorsal body (DB) acceleration and median DB amplitude also increased. This, in turn, led to higher airspeeds, suggesting that birds fly slower when traversing unfamiliar terrain. By contrast, after route efficiency stabilised, birds exhibited increasing wingbeat frequencies, which did not result in further increases in speed. Overall, higher wind support was also associated with lower wingbeat frequencies and increased DB amplitude. Our study suggests that the cost of early flights from an unfamiliar location may be higher than subsequent flights because of both inefficient routes (increased distance) and lower airspeeds (increased time). Furthermore, the results indicate, for the first time, that birds modulate their wingbeat characteristics as a function of navigational knowledge, and suggest that flight characteristics may be used as 'signatures' of birds' route familiarity. © 2017. Published by The Company of Biologists Ltd.

Non-Epitaxial Thin-Film Indium Phosphide Photovoltaics: Growth, Devices, and Cost Analysis

NASA Astrophysics Data System (ADS)

Zheng, Maxwell S.

In recent years, the photovoltaic market has grown significantly as module prices have continued to come down. Continued growth of the field requires higher efficiency modules at lower manufacturing costs. In particular, higher efficiencies reduce the area needed for a given power output, thus reducing the downstream balance of systems costs that scale with area such as mounting frames, installation, and soft costs. Cells and modules made from III-V materials have the highest demonstrated efficiencies to date but are not yet at the cost level of other thin film technologies, which has limited their large-scale deployment. There is a need for new materials growth, processing and fabrication techniques to address this major shortcoming of III-V semiconductors. Chapters 2 and 3 explore growth of InP on non-epitaxial Mo substrates by MOCVD and CSS, respectively. The results from these studies demonstrate that InP optoelectronic quality is maintained even by growth on non-epitaxial metal substrates. Structural characterization by SEM and XRD show stoichiometric InP can be grown in complete thin films on Mo. Photoluminescence measurements show peak energies and widths to be similar to those of reference wafers of similar doping concentrations. In chapter 4 the TF-VLS growth technique is introduced and cells fabricated from InP produced by this technique are characterized. The TF-VLS method results in lateral grain sizes of >500 mum and exhibits superior optoelectronic quality. First generation devices using a n-TiO2 window layer along with p-type TF-VLS grown InP have reached ˜12.1% power conversion efficiency under 1 sun illumination with VOC of 692 mV, JSC of 26.9 mA/cm2, and FF of 65%. The cells are fabricated using all non-epitaxial processing. Optical measurements show the InP in these cells have the potential to support a higher VOC of ˜795 mV, which can be achieved by improved device design. Chapter 5 describes a cost analysis of a manufacturing process using an InP cell as the active layer in a monolithically integrated module. Importantly, TF-VLS growth avoids the hobbles of traditional growth: the epitaxial wafer substrate, low utilization efficiency of expensive metalorganic precursors, and high capital depreciation costs due to low throughput. Production costs are projected to be 0.76/W(DC) for the benchmark case of 12% efficient modules and would decrease to 0.40/W(DC) for the long-term potential case of 24% efficient modules.

Phase-modulated radio over fiber multimode links.

PubMed

Gasulla, Ivana; Capmany, José

2012-05-21

We present the first experimental demonstration of a phase-modulated MMF link implementing high-frequency digital transmission in a cost-effective solution based on direct detection. Successful subcarrier transmission of QPSK, 16-QAM and 64-QAM data channels for bit rates up to 120 Mb/s through a 5 km MMF link is achieved over the microwave region comprised between 6 and 20 GHz. The overall capacity of the proposed approach can be further increased by properly accommodating more passband channels in the operative frequency range determined by the phase-to-intensity conversion process provided by the dispersive nature of the optical fiber. In this sense, our results show the possibility of achieving an aggregate bit rate per length product of 144 Gb/s · km and confirm, in consequence, the possibility of broadband phase-modulated radio over fiber transmission through MMF links suitable for multichannel SCM signal distribution.

Module/array interface study

NASA Technical Reports Server (NTRS)

1978-01-01

Several aspects of module design are evaluated, including glass superstrate and metal substrate module configurations, the potential for hail damage, light absorption in glass superstrates, the economics of glass selection, and electrical design. Also, three alternate glass superstrate module configurations are evaluated by means of finite element computer analyses. Two panel sizes, 1.2 by 2.4 m (4 by 8 ft) and 2.4 by 4.8 m are used to support three module sizes, 0.6 by 1.2 m, 1.2 by 1.2 m, and 1.2 by 2.4 m, for design loadings of + or - 1.7 kPa, + or - 2.4 kPa, and + or - 3.6 kPa. Designs and cost estimates are presented for twenty panel types and nine array configurations at each of the three design loadings. Structural cost sensitivities of combined array configurations and panel cases are presented.

Stable, low cost SAW microwave transmitter

NASA Astrophysics Data System (ADS)

Lau, K. F.; Yen, K. H.

1986-06-01

The design flexibility and application possibilities of surface acoustic wave (SAW) technology is discussed. When a highly stable, AM-modulated transmitter is required, a SAW resonator can provide an oscillator Q of up to 20,000 at 1 GHz. When FM modulation is required, the SAW delay line can provide a lower oscillator Q, which represents the optimum tradeoff between frequency stability and FM modulability. The capabilities of SAW oscillators are reviewed, and two example transmitters are presented. One transmitter operates at 1680 MHz and provides an AM-modulated signal. The second operates at the 400 to 406 MHz range and provides an FM-modulated output at one of six frequencies. SAW transmitters are suitable for applications where moderately high stability and low cost are key factors. With direct generation of signals at microwave frequencies and the flexibility of SAW oscillator design, a wide range of performance characteristics can be achieved.

Silicon dendritic web material

NASA Technical Reports Server (NTRS)

Meier, D. L.; Campbell, R. B.; Sienkiewicz, L. J.; Rai-Choudhury, P.

1982-01-01

The development of a low cost and reliable contact system for solar cells and the fabrication of several solar cell modules using ultrasonic bonding for the interconnection of cells and ethylene vinyl acetate as the potting material for module encapsulation are examined. The cells in the modules were made from dendritic web silicon. To reduce cost, the electroplated layer of silver was replaced with an electroplated layer of copper. The modules that were fabricated used the evaporated Ti, Pd, Ag and electroplated Cu (TiPdAg/Cu) system. Adherence of Ni to Si is improved if a nickel silicide can be formed by heat treatment. The effectiveness of Ni as a diffusion barrier to Cu and the ease with which nickel silicide is formed is discussed. The fabrication of three modules using dendritic web silicon and employing ultrasonic bonding for interconnecting calls and ethylene vinyl acetate as the potting material is examined.

Silicon dendritic web material

NASA Astrophysics Data System (ADS)

Meier, D. L.; Campbell, R. B.; Sienkiewicz, L. J.; Rai-Choudhury, P.

1982-03-01

The development of a low cost and reliable contact system for solar cells and the fabrication of several solar cell modules using ultrasonic bonding for the interconnection of cells and ethylene vinyl acetate as the potting material for module encapsulation are examined. The cells in the modules were made from dendritic web silicon. To reduce cost, the electroplated layer of silver was replaced with an electroplated layer of copper. The modules that were fabricated used the evaporated Ti, Pd, Ag and electroplated Cu (TiPdAg/Cu) system. Adherence of Ni to Si is improved if a nickel silicide can be formed by heat treatment. The effectiveness of Ni as a diffusion barrier to Cu and the ease with which nickel silicide is formed is discussed. The fabrication of three modules using dendritic web silicon and employing ultrasonic bonding for interconnecting calls and ethylene vinyl acetate as the potting material is examined.

Growth Of High-Cost Intensity-Modulated Radiotherapy For Prostate Cancer Raises Concerns About Overuse

PubMed Central

Jacobs, Bruce L.; Zhang, Yun; Skolarus, Ted A.; Hollenbeck, Brent K.

2012-01-01

To study the impact of new, expensive, and unproven therapies to treat prostate cancer, we investigated the dissemination of intensity-modulated radiotherapy (IMRT). IMRT is an innovative treatment for prostate cancer that delivers higher doses of radiation with improved precision compared to alternative radiotherapies. We observed rapid adoption of this new treatment among men diagnosed with prostate cancer from 2001 through 2007, despite uncertainty about its relative effectiveness. We compared patient and disease characteristics of those receiving IMRT and the previous radiation standard of care, three-dimensional conformal therapy; assessed intermediate-term outcomes; and examined potential factors associated with the increased use of IMRT. We found that in the early period of IMRT adoption (2001–03) men with high-risk disease were more likely to receive IMRT, whereas after IMRT’s initial dissemination (2004–07) men with low-risk disease had fairly similar likelihoods of receiving IMRT as men with high-risk disease. This raises concerns about overtreatment, as well as considerable health care costs, because treatment with IMRT costs $15,000–$20,000 more than other standard therapies. As health care delivery reforms gain traction, policy makers must balance the promotion of new, yet unproven, technology with the risk of overuse. PMID:22492892

Model documentation renewable fuels module of the National Energy Modeling System

NASA Astrophysics Data System (ADS)

1995-06-01

This report documents the objectives, analytical approach, and design of the National Energy Modeling System (NEMS) Renewable Fuels Module (RFM) as it relates to the production of the 1995 Annual Energy Outlook (AEO95) forecasts. The report catalogs and describes modeling assumptions, computational methodologies, data inputs, and parameter estimation techniques. A number of offline analyses used in lieu of RFM modeling components are also described. The RFM consists of six analytical submodules that represent each of the major renewable energy resources -- wood, municipal solid waste (MSW), solar energy, wind energy, geothermal energy, and alcohol fuels. The RFM also reads in hydroelectric facility capacities and capacity factors from a data file for use by the NEMS Electricity Market Module (EMM). The purpose of the RFM is to define the technological, cost, and resource size characteristics of renewable energy technologies. These characteristics are used to compute a levelized cost to be competed against other similarly derived costs from other energy sources and technologies. The competition of these energy sources over the NEMS time horizon determines the market penetration of these renewable energy technologies. The characteristics include available energy capacity, capital costs, fixed operating costs, variable operating costs, capacity factor, heat rate, construction lead time, and fuel product price.

ALEC (Aggregate Lifecycle Effectiveness and Cost): A Model for Analyzing the Cost-Effectiveness of Air Force Enlisted Personnel Policies. Volume 2. Documentation and User’s Guide.

DTIC Science & Technology

1987-08-01

225686 458892 875261 29791 162090 40137 1791858 IL R -A I.11 i - - - - -- _ _ __ _ _ ...4" .. ... "In m ur ln nm m i -73- V1.OUTPUT MODULE This module...Reenlist bonus 0 29791 29791 Crossflow fees 17271 40137 22865 Total 1417261 1791858 374597 - 75 - Table 7.3 GUIDELINES FOR CHOOSING MANAGEMENT

Development and application of Model of Resource Utilization, Costs, and Outcomes for Stroke (MORUCOS): an Australian economic model for stroke.

PubMed

Mihalopoulos, Catherine; Cadilhac, Dominique A; Moodie, Marjory L; Dewey, Helen M; Thrift, Amanda G; Donnan, Geoffrey A; Carter, Robert C

2005-01-01

To outline the development, structure, data assumptions, and application of an Australian economic model for stroke (Model of Resource Utilization, Costs, and Outcomes for Stroke [MORUCOS]). The model has a linked spreadsheet format with four modules to describe the disease burden and treatment pathways, estimate prevalence-based and incidence-based costs, and derive life expectancy and quality of life consequences. The model uses patient-level, community-based, stroke cohort data and macro-level simulations. An interventions module allows options for change to be consistently evaluated by modifying aspects of the other modules. To date, model validation has included sensitivity testing, face validity, and peer review. Further validation of technical and predictive accuracy is needed. The generic pathway model was assessed by comparison with a stroke subtypes (ischemic, hemorrhagic, or undetermined) approach and used to determine the relative cost-effectiveness of four interventions. The generic pathway model produced lower costs compared with a subtypes version (total average first-year costs/case AUD$ 15,117 versus AUD$ 17,786, respectively). Optimal evidence-based uptake of anticoagulation therapy for primary and secondary stroke prevention and intravenous thrombolytic therapy within 3 hours of stroke were more cost-effective than current practice (base year, 1997). MORUCOS is transparent and flexible in describing Australian stroke care and can effectively be used to systematically evaluate a range of different interventions. Adjusting results to account for stroke subtypes, as they influence cost estimates, could enhance the generic model.

Advanced light source technologies that enable high-volume manufacturing of DUV lithography extensions

NASA Astrophysics Data System (ADS)

Cacouris, Theodore; Rao, Rajasekhar; Rokitski, Rostislav; Jiang, Rui; Melchior, John; Burfeindt, Bernd; O'Brien, Kevin

2012-03-01

Deep UV (DUV) lithography is being applied to pattern increasingly finer geometries, leading to solutions like double- and multiple-patterning. Such process complexities lead to higher costs due to the increasing number of steps required to produce the desired results. One of the consequences is that the lithography equipment needs to provide higher operating efficiencies to minimize the cost increases, especially for producers of memory devices that experience a rapid decline in sales prices of these products over time. In addition to having introduced higher power 193nm light sources to enable higher throughput, we previously described technologies that also enable: higher tool availability via advanced discharge chamber gas management algorithms; improved process monitoring via enhanced on-board beam metrology; and increased depth of focus (DOF) via light source bandwidth modulation. In this paper we will report on the field performance of these technologies with data that supports the desired improvements in on-wafer performance and operational efficiencies.

Development of High Efficiency (14%) Solar Cell Array Module

NASA Technical Reports Server (NTRS)

Iles, P. A.; Khemthong, S.; Olah, S.; Sampson, W. J.; Ling, K. S.

1979-01-01

High efficiency solar cells required for the low cost modules was developed. The production tooling for the manufacture of the cells and modules was designed. The tooling consisted of: (1) back contact soldering machine; (2) vacuum pickup; (3) antireflective coating tooling; and (4) test fixture.

Quantitative steps in the evolution of metabolic organisation as specified by the Dynamic Energy Budget theory.

PubMed

Kooijman, S A L M; Troost, T A

2007-02-01

The Dynamic Energy Budget (DEB) theory quantifies the metabolic organisation of organisms on the basis of mechanistically inspired assumptions. We here sketch a scenario for how its various modules, such as maintenance, storage dynamics, development, differentiation and life stages could have evolved since the beginning of life. We argue that the combination of homeostasis and maintenance induced the development of reserves and that subsequent increases in the maintenance costs came with increases of the reserve capacity. Life evolved from a multiple reserves - single structure system (prokaryotes, many protoctists) to systems with multiple reserves and two structures (plants) or single reserve and single structure (animals). This had profound consequences for the possible effects of temperature on rates. We present an alternative explanation for what became known as the down-regulation of maintenance at high growth rates in microorganisms; the density of the limiting reserve increases with the growth rate, and reserves do not require maintenance while structure-specific maintenance costs are independent of the growth rate. This is also the mechanism behind the variation of the respiration rate with body size among species. The DEB theory specifies reserve dynamics on the basis of the requirements of weak homeostasis and partitionability. We here present a new and simple mechanism for this dynamics which accounts for the rejection of mobilised reserve by busy maintenance/growth machinery. This module, like quite a few other modules of DEB theory, uses the theory of Synthesising Units; we review recent progress in this field. The plasticity of membranes that evolved in early eukaryotes is a major step forward in metabolic evolution; we discuss quantitative aspects of the efficiency of phagocytosis relative to the excretion of digestive enzymes to illustrate its importance. Some processes of adaptation and gene expression can be understood in terms of allocation linked to the relative workload of metabolic modules in (unicellular) prokaryotes and organs in (multicellular) eukaryotes. We argue that the evolution of demand systems can only be understood in the light of that of supply systems. We illustrate some important points with data from the literature.

Modulating light propagation in ZnO-Cu₂O-inverse opal solar cells for enhanced photocurrents.

PubMed

Yantara, Natalia; Pham, Thi Thu Trang; Boix, Pablo P; Mathews, Nripan

2015-09-07

The advantages of employing an interconnected periodic ZnO morphology, i.e. an inverse opal structure, in electrodeposited ZnO/Cu2O devices are presented. The solar cells are fabricated using low cost solution based methods such as spin coating and electrodeposition. The impact of inverse opal geometry, mainly the diameter and thickness, is scrutinized. By employing 3 layers of an inverse opal structure with a 300 nm pore diameter, higher short circuit photocurrents (∼84% improvement) are observed; however the open circuit voltages decrease with increasing interfacial area. Optical simulation using a finite difference time domain method shows that the inverse opal structure modulates light propagation within the devices such that more photons are absorbed close to the ZnO/Cu2O junction. This increases the collection probability resulting in improved short circuit currents.

Defect design of insulation systems for photovoltaic modules

NASA Technical Reports Server (NTRS)

Mon, G. R.

1981-01-01

A defect-design approach to sizing electrical insulation systems for terrestrial photovoltaic modules is presented. It consists of gathering voltage-breakdown statistics on various thicknesses of candidate insulation films where, for a designated voltage, module failure probabilities for enumerated thickness and number-of-layer film combinations are calculated. Cost analysis then selects the most economical insulation system. A manufacturing yield problem is solved to exemplify the technique. Results for unaged Mylar suggest using fewer layers of thicker films. Defect design incorporates effects of flaws in optimal insulation system selection, and obviates choosing a tolerable failure rate, since the optimization process accomplishes that. Exposure to weathering and voltage stress reduces the voltage-withstanding capability of module insulation films. Defect design, applied to aged polyester films, promises to yield reliable, cost-optimal insulation systems.

Thin film module development

NASA Technical Reports Server (NTRS)

Jester, T.

1985-01-01

The design of ARCO Solar, Inc.'s Genesis G100 photovoltaic module was driven by several criteria, including environmental stability (both electrical and mechanical), consumer aesthetics, low materials costs, and manufacturing ease. The module circuitry is designed as a 12 volt battery charger, using monolithic patterning techniques on a glass superstrate. This patterning and interconnect method proves amenable to high volume, low cost production throughput, and the use of glass serves the dual role of handling ease and availability. The mechanical design of the module centers on environmental stability. Packaging of the glass superstrate circuit must provide good resistance to thermal and humidity exposure along with hi-pot insulation and hailstone impact resistance. The options considered are given. Ethylene vinyl acetate (EVA) is chosen as the pottant material for its excellent weatherability.

Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agamy, Mohammed

The “Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System” program is focused on developing innovative concepts for residential photovoltaic (PV) systems with the following objectives: to create an Innovative micro-inverter topology that reduces the cost from the best in class micro-inverter and provides high efficiency (>96% CEC - California Energy Commission), and 25+ year warranty, as well as reactive power support; integrate micro-inverter and PV module to reduce system price by at least $0.25/W through a) accentuating dual use of the module metal frame as a large area heat spreader reducing operating temperature, and b) eliminating redundant wiringmore » and connectors; and create micro-inverter controller handles smart grid and safety functions to simplify implementation and reduce cost.« less

Application of Distributed DC/DC Electronics in Photovoltaic Systems

NASA Astrophysics Data System (ADS)

Kabala, Michael

In a typical residential, commercial or utility grade photovoltaic (PV) system, PV modules are connected in series and in parallel to form an array that is connected to a standard DC/AC inverter, which is then connected directly to the grid. This type of standard installation; however, does very little to maximize the energy output of the solar array if certain conditions exist. These conditions could include age, temperature, irradiance and other factors that can cause mismatch between PV modules in an array that severely cripple the output power of the system. Since PV modules are typically connected in series to form a string, the output of the entire string is limited by the efficiency of the weakest module. With PV module efficiencies already relatively low, it is critical to extract the maximum power out of each module in order to make solar energy an economically viable competitor to oil and gas. Module level DC/DC electronics with maximum power point (MPP) tracking solves this issue by decoupling each module from the string in order for the module to operate independently of the geometry and complexity of the surrounding system. This allows each PV module to work at its maximum power point by transferring the maximum power the module is able to deliver directly to the load by either boosting (stepping up) the voltage or bucking (stepping down) the voltage. The goal of this thesis is to discuss the development of a per-module DC/DC converter in order to maximize the energy output of a PV module and reduce the overall cost of the system by increasing the energy harvest.

Communications network design and costing model programmers manual

NASA Technical Reports Server (NTRS)

Logan, K. P.; Somes, S. S.; Clark, C. A.

1983-01-01

Otpimization algorithms and techniques used in the communications network design and costing model for least cost route and least cost network problems are examined from the programmer's point of view. All system program modules, the data structures within the model, and the files which make up the data base are described.

Characterization of the Ecosole HCPV tracker and single module inverter

NASA Astrophysics Data System (ADS)

Carpanelli, Maurizio; Borelli, Gianni; Verdilio, Daniele; De Nardis, Davide; Migali, Fabrizio; Cancro, Carmine; Graditi, Giorgio

2015-09-01

BECAR, the Beghelli group's R&D company, is leading ECOSOLE (Elevated COncentration SOlar Energy), one of the largest European Demonstration projects in solar photovoltaic. ECOSOLE, started in 2012, is focused on the study, design, and realization of new HCPV generator made of high efficiency PV modules equipped with SoG (Silicone on Glass) fresnel lenses and III-V solar cells, and a low cost matched solar tracker with distributed inverters approach. The project also regards the study and demonstration of new high throughput methods for the industrial large scale productions, at very low manufacturing costs. This work reports the description of the characterization of the tracker and single module.

A Module Experimental Process System Development Unit (MEPSDU). [development of low cost solar arrays

NASA Technical Reports Server (NTRS)

1981-01-01

The technical readiness of a cost effective process sequence that has the potential for the production of flat plate photovoltaic modules which met the price goal in 1986 of $.70 or less per Watt peak was demonstrated. The proposed process sequence was reviewed and laboratory verification experiments were conducted. The preliminary process includes the following features: semicrystalline silicon (10 cm by 10 cm) as the silicon input material; spray on dopant diffusion source; Al paste BSF formation; spray on AR coating; electroless Ni plate solder dip metallization; laser scribe edges; K & S tabbing and stringing machine; and laminated EVA modules.

Radiation oncology services in the modern era: evolving patterns of usage and payments in the office setting for medicare patients from 2000 to 2010.

PubMed

Shen, Xinglei; Showalter, Timothy N; Mishra, Mark V; Barth, Sanford; Rao, Vijay; Levin, David; Parker, Laurence

2014-07-01

We evaluated long-term changes in the volume and payments for radiation oncology services in the intensity-modulated radiation therapy (IMRT) era from 2000 to 2010 using a database of Medicare claims. We used the Medicare Physician/Supplier Procedure Summary Master File (PSPSMF) for each year from 2000 to 2010 to tabulate the volume and payments for radiation oncology services. This database provides a summary of each billing code submitted to Medicare part B. We identified all codes used in radiation oncology services and categorized billing codes by treatment modality and place of service. We focused our analysis on office-based practices. Total office-based patient volume increased 8.2% from 2000 to 2010, whereas total payments increased 217%. Increase in overall payments increased dramatically from 2000 to 2007, but subsequently plateaued from 2008 to 2010. Increases in complexity of care, and image guidance in particular, have also resulted in higher payments. The cost of radiation oncology services increased from 2000 to 2010, mostly due to IMRT, but also with significant contribution from increased overall complexity of care. A cost adjustment occurred after 2007, limiting further growth of payments. Future health policy studies should explore the potential for further cost containment, including differences in use between freestanding and hospital outpatient facilities. Copyright © 2014 by American Society of Clinical Oncology.

Development of efficient and cost-effective distributed hydrological modeling tool MWEasyDHM based on open-source MapWindow GIS

NASA Astrophysics Data System (ADS)

Lei, Xiaohui; Wang, Yuhui; Liao, Weihong; Jiang, Yunzhong; Tian, Yu; Wang, Hao

2011-09-01

Many regions are still threatened with frequent floods and water resource shortage problems in China. Consequently, the task of reproducing and predicting the hydrological process in watersheds is hard and unavoidable for reducing the risks of damage and loss. Thus, it is necessary to develop an efficient and cost-effective hydrological tool in China as many areas should be modeled. Currently, developed hydrological tools such as Mike SHE and ArcSWAT (soil and water assessment tool based on ArcGIS) show significant power in improving the precision of hydrological modeling in China by considering spatial variability both in land cover and in soil type. However, adopting developed commercial tools in such a large developing country comes at a high cost. Commercial modeling tools usually contain large numbers of formulas, complicated data formats, and many preprocessing or postprocessing steps that may make it difficult for the user to carry out simulation, thus lowering the efficiency of the modeling process. Besides, commercial hydrological models usually cannot be modified or improved to be suitable for some special hydrological conditions in China. Some other hydrological models are open source, but integrated into commercial GIS systems. Therefore, by integrating hydrological simulation code EasyDHM, a hydrological simulation tool named MWEasyDHM was developed based on open-source MapWindow GIS, the purpose of which is to establish the first open-source GIS-based distributed hydrological model tool in China by integrating modules of preprocessing, model computation, parameter estimation, result display, and analysis. MWEasyDHM provides users with a friendly manipulating MapWindow GIS interface, selectable multifunctional hydrological processing modules, and, more importantly, an efficient and cost-effective hydrological simulation tool. The general construction of MWEasyDHM consists of four major parts: (1) a general GIS module for hydrological analysis, (2) a preprocessing module for modeling inputs, (3) a model calibration module, and (4) a postprocessing module. The general GIS module for hydrological analysis is developed on the basis of totally open-source GIS software, MapWindow, which contains basic GIS functions. The preprocessing module is made up of three submodules including a DEM-based submodule for hydrological analysis, a submodule for default parameter calculation, and a submodule for the spatial interpolation of meteorological data. The calibration module contains parallel computation, real-time computation, and visualization. The postprocessing module includes model calibration and model results spatial visualization using tabular form and spatial grids. MWEasyDHM makes it possible for efficient modeling and calibration of EasyDHM, and promises further development of cost-effective applications in various watersheds.

Modulated Chlorophyll "a" Fluorescence: A Tool for Teaching Photosynthesis

ERIC Educational Resources Information Center

Marques da Silva, Jorge; Bernardes da Silva, Anabela; Padua, Mario

2007-01-01

"In vivo" chlorophyll "a" fluorescence is a key technique in photosynthesis research. The recent release of a low cost, commercial, modulated fluorometer enables this powerful technology to be used in education. Modulated chlorophyll a fluorescence measurement "in vivo" is here proposed as a tool to demonstrate basic…

Photovoltaic Module Reliability Workshop 2011: February 16-17, 2011

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Photovoltaic Module Reliability Workshop 2014: February 25-26, 2014

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2014-02-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2013-10-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, J.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

2016 NREL Photovoltaic Module Reliability Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology - both critical goals for moving PV technologies deeper into the electricity marketplace.

2015 NREL Photovoltaic Module Reliability Workshops

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Module encapsulation technology

NASA Technical Reports Server (NTRS)

Willis, P.

1986-01-01

The identification and development techniques for low-cost module encapsulation materials were reviewed. Test results were displayed for a variety of materials. The improved prospects for modeling encapsulation systems for life prediction were reported.

Terrestrial central station array life-cycle analysis support study

NASA Technical Reports Server (NTRS)

1978-01-01

Plant elements evaluated included designs for module, panel and array structures, as well as balance-of-plant systems. Installation and maintenance procedures and the impact of site environment were also evaluated. In terms of the cost of energy produced, the horizontal array configuration was found to be less expensive than the tandem array at latitudes less than 40 deg. Both of these configurations are less expensive than the rack design. However, the costs of energy for all three configurations are within approximately ?10 percent of each other. For flat plate panels, the seasonally adjusted and tracking array configurations are not economically attractive when compared to the three other designs. Balance-of-plant costs are approximately equal to (goal) module costs. The array structures and foundations are the most expensive items in the balance-of-plant costs.

Test module development to detect the flase call probe pins on microeprocessor test equipment

NASA Astrophysics Data System (ADS)

Tang, L. W.; Ong, N. R.; Mohamad, I. S. B.; Alcain, J. B.; Retnasamy, V.

2017-09-01

Probe pins are useful for electrical testing of microelectronic components, printed circuit board assembly (PCBA), microprocessors and other electronic devices due to it provides the conductivity test based on specific device circuit design. During the repeatable test runs, the load of test modules, contact failures and the current conductivity induces layer wear off all the tip of probe pins contact. Contamination will be build-up on probe pins and increased contact resistivity which results of cost loss and time loss for rectifying programs, rectifying testers and exchanging new probe pins. In this study, a resistivity approach will be developed to provide "Testing of Test Probes". The test module based on "Four-wire Ohm measurement" method with two alternative ways of applying power supply, that are 9V from a single power supply and 5V from Arduino UNO power supply were demonstrated to measure the small resistance value of microprocessor probe pin. A microcontroller with VEE Pro software was used to record the measurement data. The accuracy of both test modules were calibrated under different temperature conditions and result shows that 9V from a single power supply test module has higher measurement accuracy.

High Voltage, Fast-Switching Module for Active Control of Magnetic Fields and Edge Plasma Currents

NASA Astrophysics Data System (ADS)

Ziemba, Timothy; Miller, Kenneth; Prager, James; Slobodov, Ilia

2016-10-01

Fast, reliable, real-time control of plasma is critical to the success of magnetic fusion science. High voltage and current supplies are needed to mitigate instabilities in all experiments as well as disruption events in large scale tokamaks for steady-state operation. Silicon carbide (SiC) MOSFETs offer many advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities; however, these devices are limited to 1.2-1.7 kV devices. As fusion enters the long-pulse and burning plasma eras, efficiency of power switching will be important. Eagle Harbor Technologies (EHT), Inc. developing a high voltage SiC MOSFET module that operates at 10 kV. This switch module utilizes EHT gate drive technology, which has demonstrated the ability to increase SiC MOSFET switching efficiency. The module will allow more rapid development of high voltage switching power supplies at lower cost necessary for the next generation of fast plasma feedback and control. EHT is partnering with the High Beta Tokamak group at Columbia to develop detailed high voltage module specifications, to ensure that the final product meets the needs of the fusion science community.

Array automated assembly task low cost silicon solar array project, phase 2

NASA Technical Reports Server (NTRS)

Olson, C.

1980-01-01

Analyses of solar cell and module process steps for throughput rate, cost effectiveness, and reproductibility are reported. In addition to the concentration on cell and module processing sequences, an investigation was made into the capability of using microwave energy in the diffusion, sintering, and thick film firing steps of cell processing. Although the entire process sequence was integrated, the steps are treated individually with test and experimental data, conclusions, and recommendations.

Modeling of solar polygeneration plant

NASA Astrophysics Data System (ADS)

Leiva, Roberto; Escobar, Rodrigo; Cardemil, José

2017-06-01

In this work, a exergoeconomic analysis of the joint production of electricity, fresh water, cooling and process heat for a simulated concentrated solar power (CSP) based on parabolic trough collector (PTC) with thermal energy storage (TES) and backup energy system (BS), a multi-effect distillation (MED) module, a refrigeration absorption module, and process heat module is carried out. Polygeneration plant is simulated in northern Chile in Crucero with a yearly total DNI of 3,389 kWh/m2/year. The methodology includes designing and modeling a polygeneration plant and applying exergoeconomic evaluations and calculating levelized cost. Solar polygeneration plant is simulated hourly, in a typical meteorological year, for different solar multiple and hour of storage. This study reveals that the total exergy cost rate of products (sum of exergy cost rate of electricity, water, cooling and heat process) is an alternative method to optimize a solar polygeneration plant.

Costs of mate-guarding in wild male long-tailed macaques (Macaca fascicularis): physiological stress and aggression.

PubMed

Girard-Buttoz, Cédric; Heistermann, Michael; Rahmi, Erdiansyah; Agil, Muhammad; Fauzan, Panji Ahmad; Engelhardt, Antje

2014-09-01

Mate-guarding is an important determinant of male reproductive success in a number of species. However, it is known to potentially incur costs. The aim of the present study was to assess the effect of mate-guarding on male physiological stress and aggression in long-tailed macaques, a species in which males mate-guard females to a lesser extent than predicted by the Priority of Access model (PoA). The study was carried out during two mating periods on three groups of wild long-tailed macaques in Indonesia by combining behavioral observations with non-invasive measurements of fecal glucocorticoid (fGC) levels. Mate-guarding was associated with a general rise in male stress hormone levels but, from a certain threshold of mate-guarding onwards, increased vigilance time was associated with a decrease in stress hormone output. Mate-guarding also increased male-male aggression rate and male vigilance time. Overall, alpha males were more physiologically stressed than other males independently of mating competition. Increased glucocorticoid levels during mate-guarding are most likely adaptive since it may help males to mobilize extra-energy required for mate-guarding and ultimately maintain a balanced energetic status. However, repeated exposure to high levels of stress over an extended period is potentially deleterious to the immune system and thus may carry costs. This potential physiological cost together with the cost of increased aggression mate-guarding male face may limit the male's ability to mate-guard females, explaining the deviance from the PoA model observed in long-tailed macaques. Comparing our results to previous findings we discuss how ecological factors, reproductive seasonality and rank achievement may modulate the extent to which costs of mate-guarding limit male monopolization abilities. Copyright © 2014. Published by Elsevier Inc.

Polarization digital holographic microscopy using low-cost liquid crystal polarization rotators

NASA Astrophysics Data System (ADS)

Dovhaliuk, Rostyslav Yu

2018-02-01

Polarization imaging methods are actively used to study anisotropic objects. A number of methods and systems, such as imaging polarimeters, were proposed to measure the state of polarization of light that passed through the object. Digital holographic and interferometric approaches can be used to quantitatively measure both amplitude and phase of a wavefront. Using polarization modulation optics, the measurement capabilities of such interference-based systems can be extended to measure polarization-dependent parameters, such as phase retardation. Different kinds of polarization rotators can be used to alternate the polarization of a reference beam. Liquid crystals are used in a rapidly increasing number of different optoelectronic devices. Twisted nematic liquid crystals are widely used as amplitude modulators in electronic displays and light valves or shutter glass. Such devices are of particular interest for polarization imaging, as they can be used as polarization rotators, and due to large-scale manufacturing have relatively low cost. A simple Mach-Zehnder polarized holographic setup that uses modified shutter glass as a polarization rotator is demonstrated. The suggested approach is experimentally validated by measuring retardation of quarter-wave film.

Shorter Lines Facilitate Reading in Those Who Struggle

PubMed Central

Schneps, Matthew H.; Thomson, Jenny M.; Sonnert, Gerhard; Pomplun, Marc; Chen, Chen; Heffner-Wong, Amanda

2013-01-01

People with dyslexia, who ordinarily struggle to read, sometimes remark that reading is easier when e-readers are used. Here, we used eye tracking to observe high school students with dyslexia as they read using these devices. Among the factors investigated, we found that reading using a small device resulted in substantial benefits, improving reading speeds by 27%, reducing the number of fixations by 11%, and importantly, reducing the number of regressive saccades by more than a factor of 2, with no cost to comprehension. Given that an expected trade-off between horizontal and vertical regression was not observed when line lengths were altered, we speculate that these effects occur because sluggish attention spreads perception to the left as the gaze shifts during reading. Short lines eliminate crowded text to the left, reducing regression. The effects of attention modulation by the hand, and of increased letter spacing to reduce crowding, were also found to modulate the oculomotor dynamics in reading, but whether these factors resulted in benefits or costs depended on characteristics, such as visual attention span, that varied within our sample. PMID:23940709

Shorter lines facilitate reading in those who struggle.

PubMed

Schneps, Matthew H; Thomson, Jenny M; Sonnert, Gerhard; Pomplun, Marc; Chen, Chen; Heffner-Wong, Amanda

2013-01-01

People with dyslexia, who ordinarily struggle to read, sometimes remark that reading is easier when e-readers are used. Here, we used eye tracking to observe high school students with dyslexia as they read using these devices. Among the factors investigated, we found that reading using a small device resulted in substantial benefits, improving reading speeds by 27%, reducing the number of fixations by 11%, and importantly, reducing the number of regressive saccades by more than a factor of 2, with no cost to comprehension. Given that an expected trade-off between horizontal and vertical regression was not observed when line lengths were altered, we speculate that these effects occur because sluggish attention spreads perception to the left as the gaze shifts during reading. Short lines eliminate crowded text to the left, reducing regression. The effects of attention modulation by the hand, and of increased letter spacing to reduce crowding, were also found to modulate the oculomotor dynamics in reading, but whether these factors resulted in benefits or costs depended on characteristics, such as visual attention span, that varied within our sample.

Recruitment and Retention of Volunteers in a Citizen Science Network to Detect Invasive Species on Private Lands

NASA Astrophysics Data System (ADS)

Andow, David A.; Borgida, Eugene; Hurley, Terrance M.; Williams, Allison L.

2016-10-01

Volunteer citizen monitoring is an increasingly important source of scientific data. We developed a volunteer program for early detection of new invasive species by private landowners on their own land. Early detection of an invasive species, however, subjects the landowner to the potentially costly risk of government intervention to control the invasive species. We hypothesized that an adult experiential learning module could increase recruitment and retention because private landowners could learn more about and understand the social benefits of early detection and more accurately gauge the level of personal risk. The experiential learning module emphasized group discussion and individual reflection of risks and benefits of volunteering and included interactions with experts and regulatory personnel. A population of woodland owners with >2 ha of managed oak woodland in central Minnesota were randomly assigned to recruitment treatments: (a) the experiential learning module or (b) a letter inviting their participation. The recruitment and retention rates and data quality were similar for the two methods. However, volunteers who experienced the learning module were more likely to recruit new volunteers than those who merely received an invitation letter. Thus the module may indirectly affect recruitment of new volunteers. The data collection was complex and required the volunteers to complete timely activities, yet the volunteers provided sufficiently high quality data that was useful to the organizers. Volunteers can collect complex data and are willing to assume personal risk to contribute to early detection of invasive species.

Recruitment and Retention of Volunteers in a Citizen Science Network to Detect Invasive Species on Private Lands.

PubMed

Andow, David A; Borgida, Eugene; Hurley, Terrance M; Williams, Allison L

2016-10-01

Volunteer citizen monitoring is an increasingly important source of scientific data. We developed a volunteer program for early detection of new invasive species by private landowners on their own land. Early detection of an invasive species, however, subjects the landowner to the potentially costly risk of government intervention to control the invasive species. We hypothesized that an adult experiential learning module could increase recruitment and retention because private landowners could learn more about and understand the social benefits of early detection and more accurately gauge the level of personal risk. The experiential learning module emphasized group discussion and individual reflection of risks and benefits of volunteering and included interactions with experts and regulatory personnel. A population of woodland owners with >2 ha of managed oak woodland in central Minnesota were randomly assigned to recruitment treatments: (a) the experiential learning module or (b) a letter inviting their participation. The recruitment and retention rates and data quality were similar for the two methods. However, volunteers who experienced the learning module were more likely to recruit new volunteers than those who merely received an invitation letter. Thus the module may indirectly affect recruitment of new volunteers. The data collection was complex and required the volunteers to complete timely activities, yet the volunteers provided sufficiently high quality data that was useful to the organizers. Volunteers can collect complex data and are willing to assume personal risk to contribute to early detection of invasive species.

Design guide for low cost standardized payloads, volume 1

NASA Technical Reports Server (NTRS)

1972-01-01

Concept point designs of low cost and refurbishable spacecraft, subsystems, and modules revealed payload program savings up to 50 percent. The general relationship of payload approaches to program costs; cost reductions from low cost standardized payloads; cost effective application of payload reliability, MMD, repair, and refurbishment; and implementation of standardization for future spacecraft are discussed. Shuttle interfaces and support equipment for future payloads are also considered

Cost Effective Use of Free-to-Use Apps in Neurosurgery (FAN) in Developing Countries: From Clinical Decision Making to Educational Courses, Strengthening Health Care Delivery.

PubMed

Thapa, Amit; Kc, Bidur; Shakya, Bikram

2016-11-01

Financial limitations and the scarcity of technological knowledge are a major hurdle to good communication platforms, data storage, and dissemination of medical knowledge in developing countries. Out of necessity we used free-to-use apps in our practice. We studied the applicability and cost effective aspect of a systematic use of these apps in neurosurgery. We designed the Free-to-use apps in neurosurgery (FAN) module in 4 phases at Kathmandu Medical College Teaching Hospital over the last 3 years. We used free apps like Viber, Dropbox, Skype, and VLC media player on 3G and Wi-Fi network. Users were trained in ethics and measures to ensure confidentiality and privacy of patient-related data. Endpoints studied were feasibility, reliability, cost effectiveness, and overall satisfaction of the users. In the FAN module, the Viber app was used to send pictures of digital images via smartphones within 30 minutes, enabling quick decisions by the consultants. Dropbox not only helped store images but also helped quick verification of discharge summaries as early as 15 minutes increasing overall efficiency. With Skype, consultants could be contacted even when they were abroad, and with the use of FAN they remain updated of their patients. By the use of Skype and VLC media player, 2 operative live workshops from abroad were transmitted live with good visual and audio reception, allowing question-and-answer sessions with the faculties. User satisfaction was more than 90%. The FAN module helped in quick reliable decision making, allowing for instantaneous communication and storing data and exchange of knowledge across countries. Copyright © 2016 Elsevier Inc. All rights reserved.

Concept and design of a fiber-optic and an I2C hybrid sensor bus system for telecommunication satellites

NASA Astrophysics Data System (ADS)

Putzer, P.; Hurni, A.; Manhart, M.; Tiefenbeck, C.; Plattner, M.; Koch, A. W.

2012-04-01

In this paper the concept and design of the Hybrid Sensor Bus (HSB) system for telecommunication satellites is presented. The HSB development in the frame of an ESA-ARTES project has been started in 2011 and the system will be tested as flight demonstrator onboard the German Heinrich Hertz communication satellite (H2Sat) in 2016. In state-of-the-art telecommunication platforms hundreds of sensors are necessary for satellite control and monitoring. The sensors are wired point-to-point (p2p) to the satellite management unit (SMU) which results in a high mass impact but preliminary increases AIT effort and thereby the overall satellite costs. Sensor bus architectures reduce AIT cost by reduction of wiring effort, reduction in required test time and by providing a flexible sensor network topology. The HSB system is based on a modular concept including a controller module, a fiber-optic interrogator module and an I²C electric interrogator module The HSB system provides advanced performance which includes programmable and sensor specific alarm functions, averaging of dedicated sensor values and thereby a reduction of SMU processor load. The combination of electrical I2C sensors for punctual resolved measurements and fiber-optic sensors for e.g. thermal mapping of panels by embedding sensor fibers in the satellite structures results in a versatile system. In this paper we present the design of the HSB system taking into account the requirements from European platform manufacturers. The HSB design yields a product which can be implemented as replacement of standard p2p systems to build up a more cost efficient sensor system for geostationary satellites.

Integrated manufacturing approach to attain benchmark team performance

NASA Astrophysics Data System (ADS)

Chen, Shau-Ron; Nguyen, Andrew; Naguib, Hussein

1994-09-01

A Self-Directed Work Team (SDWT) was developed to transfer a polyimide process module from the research laboratory to our wafer fab facility for applications in IC specialty devices. The SDWT implemented processes and tools based on the integration of five manufacturing strategies for continuous improvement. These were: Leadership Through Quality (LTQ), Total Productive Maintenance (TMP), Cycle Time Management (CTM), Activity-Based Costing (ABC), and Total Employee Involvement (TEI). Utilizing these management techniques simultaneously, the team achieved six sigma control of all critical parameters, increased Overall Equipment Effectiveness (OEE) from 20% to 90%, reduced cycle time by 95%, cut polyimide manufacturing cost by 70%, and improved its overall team member skill level by 33%.

Photothermal imaging of melanin

NASA Astrophysics Data System (ADS)

Kerimo, Josef; DiMarzio, Charles A.

2013-02-01

We present photothermal images of melanin using modulation with two laser beams. Strong melanin absorption followed by efficient nonradiative relaxation caused heating and an increase in temperature. This temperature effect was used as an imaging contrast to detect melanin. Melanin from several samples including Sepia officinalis, black human hair, and live zebra fish, were imaged with a high signal-to-noise ratio. For the imaging, we focused two near infrared laser beams (pump and probe) collinearly with different wavelengths and the pump was modulated in amplitude. The thermally induced variations in the refractive index, at the modulation frequency, were detected by the scattering of the probe beam. The Photothermal method brings several imaging benefits including the lack of background interference and the possibility of imaging for an extended period of time without photodamage to the melanin. The dependence of the photothermal signal on the laser power, modulation frequency, and spatial offset of the probe is discussed. The new photothermal imaging method is promising and provides background-free and label-free imaging of melanin and can be implemented with low-cost CW lasers.

Scalable modulation technology and the tradeoff of reach, spectral efficiency, and complexity

NASA Astrophysics Data System (ADS)

Bosco, Gabriella; Pilori, Dario; Poggiolini, Pierluigi; Carena, Andrea; Guiomar, Fernando

2017-01-01

Bandwidth and capacity demand in metro, regional, and long-haul networks is increasing at several tens of percent per year, driven by video streaming, cloud computing, social media and mobile applications. To sustain this traffic growth, an upgrade of the widely deployed 100-Gbit/s long-haul optical systems, based on polarization multiplexed quadrature phase-shift keying (PM-QPSK) modulation format associated with coherent detection and digital signal processing (DSP), is mandatory. In fact, optical transport techniques enabling a per-channel bit rate beyond 100 Gbit/s have recently been the object of intensive R and D activities, aimed at both improving the spectral efficiency and lowering the cost per bit in fiber transmission systems. In this invited contribution, we review the different available options to scale the per-channel bit-rate to 400 Gbit/s and beyond, i.e. symbol-rate increase, use of higher-order quadrature amplitude modulation (QAM) modulation formats and use of super-channels with DSP-enabled spectral shaping and advanced multiplexing technologies. In this analysis, trade-offs of system reach, spectral efficiency and transceiver complexity are addressed. Besides scalability, next generation optical networks will require a high degree of flexibility in the transponders, which should be able to dynamically adapt the transmission rate and bandwidth occupancy to the light path characteristics. In order to increase the flexibility of these transponders (often referred to as "flexponders"), several advanced modulation techniques have recently been proposed, among which sub-carrier multiplexing, hybrid formats (over time, frequency and polarization), and constellation shaping. We review these techniques, highlighting their limits and potential in terms of performance, complexity and flexibility.

A tool for cost-effectiveness analysis of field scale sediment-bound phosphorus mitigation measures and application to analysis of spatial and temporal targeting in the Lunan Water catchment, Scotland.

PubMed

Vinten, Andy; Sample, James; Ibiyemi, Adekunle; Abdul-Salam, Yakubu; Stutter, Marc

2017-05-15

The cost-effectiveness of six edge-of-field measures for mitigating diffuse pollution from sediment bound phosphorus (P) runoff from temperate arable farmland is analysed at catchment/field scales. These measures were: buffer strips, permanent grassland in the lowest 7% of arable fields, dry detention bunds, wetlands, and temporary barriers such as sediment fences. Baseline field P export was estimated using export coefficients (low risk crops) or a modified Universal Soil Loss Equation (high risk crops). The impact of measures was estimated using simple equations. Costs were estimated from gross margin losses or local data on grants. We used a net cost:benefit (NCB) factor to normalise the costs and impacts of each measure over time. Costs minimisation for target impact was done using PuLP, a linear programming module for Python, across 1634 riparian and non-riparian fields in the Lunan Water, a mixed arable catchment in Eastern Scotland. With all measures in place, average cost-effectiveness increases from £9 to £48/kg P as target P mitigation increases from 500 to 2500kg P across the catchment. Costs increase significantly when the measures available are restricted only to those currently eligible for government grants (buffers, bunds and wetlands). The assumed orientation of the average field slope makes a strong difference to the potential for storage of water by bunds and overall cost-effectiveness, but the non-funded measures can substitute for the extra expense incurred by bunds, where the slope orientation is not suitable. Economic discounting over time of impacts and costs of measures favours those measures, such as sediment fences, which are strongly targeted both spatially and temporally. This tool could be a useful guide for dialogue with land users about the potential fields to target for mitigation to achieve catchment targets. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Future GOES-R global ground receivers

NASA Astrophysics Data System (ADS)

Dafesh, P. A.; Grayver, E.

2006-08-01

The Aerospace Corporation has developed an end-to-end testbed to demonstrate a wide range of modern modulation and coding alternatives for future broadcast by the GOES-R Global Rebroadcast (GRB) system. In particular, this paper describes the development of a compact, low cost, flexible GRB digital receiver that was designed, implemented, fabricated, and tested as part of the development. This receiver demonstrates a 10-fold increase in data rate compared to the rate achievable by the current GOES generation, without a major impact on either cost or size. The digital receiver is integrated on a single PCI card with an FPGA device, and analog-to-digital converters. It supports a wide range of modulations (including 8-PSK and 16-QAM) and turbo coding. With appropriate FPGA firmware and software changes, it can also be configured to receive the current (legacy) GOES signals. The receiver has been validated by sending large image files over a high-fidelity satellite channel emulator, including a space-qualified power amplifier and a white noise source. The receiver is a key component of a future GOES-R weather receiver system (also called user terminal) that includes the antenna, low-noise amplifier, downconverter, filters, digital receiver, and receiver system software. This work describes this receiver proof of concept and its application to providing a very credible estimate of the impact of using modern modulation and coding techniques in the future GOES-R system.

NREL Report Shows Utility-Scale Solar PV System Cost Fell Nearly 30% Last

Science.gov Websites

Year | NREL | News | NREL Report Shows Utility-Scale Solar PV System Cost Fell Nearly 30% Last Year News Release: NREL Report Shows Utility-Scale Solar PV System Cost Fell Nearly 30% Last Year September 12, 2017 Record-low costs enabled by decline in module and inverter prices The installed cost of

Low-cost computer mouse for the elderly or disabled in Taiwan.

PubMed

Chen, C-C; Chen, W-L; Chen, B-N; Shih, Y-Y; Lai, J-S; Chen, Y-L

2014-01-01

A mouse is an important communication interface between a human and a computer, but it is still difficult to use for the elderly or disabled. To develop a low-cost computer mouse auxiliary tool. The principal structure of the low-cost mouse auxiliary tool is the IR (infrared ray) array module and the Wii icon sensor module, which combine with reflective tape and the SQL Server database. This has several benefits including cheap hardware cost, fluent control, prompt response, adaptive adjustment and portability. Also, it carries the game module with the function of training and evaluation; to the trainee, it is really helpful to upgrade the sensitivity of consciousness/sense and the centralization of attention. The intervention phase/maintenance phase, with regard to clicking accuracy and use of time, p value (p< 0.05) reach the level of significance. The development of the low cost adaptive computer mouse auxiliary tool was completed during the study and was also verified as having the characteristics of low cost, easy operation and the adaptability. To patients with physical disabilities, if they have independent control action parts of their limbs, the mouse auxiliary tool is suitable for them to use, i.e. the user only needs to paste the reflective tape by the independent control action parts of the body to operate the mouse auxiliary tool.

Intelligent Front-end Electronics for Silicon photodetectors (IFES)

NASA Astrophysics Data System (ADS)

Sauerzopf, Clemens; Gruber, Lukas; Suzuki, Ken; Zmeskal, Johann; Widmann, Eberhard

2016-05-01

While high channel density can be easily achieved for big experiments using custom made microchips, providing something similar for small and medium size experiments imposes a challenge. Within this work we describe a novel and cost effective solution to operate silicon photodetectors such as silicon photo multipliers (SiPM). The IFES modules provide the bias voltage for the detectors, a leading edge discriminator featuring time over threshold and a differential amplifier, all on one printed circuit board. We demonstrate under realistic conditions that the module is usable for high resolution timing measurements exploiting both charge and time information. Furthermore we show that the modules can be easily used in larger detector arrays. All in all this confirms that the IFES modules are a viable option for a broad range of experiments if cost-effectiveness and small form factor are required.

Levodopa modulates small-world architecture of functional brain networks in Parkinson's disease.

PubMed

Berman, Brian D; Smucny, Jason; Wylie, Korey P; Shelton, Erika; Kronberg, Eugene; Leehey, Maureen; Tregellas, Jason R

2016-11-01

PD is associated with disrupted connectivity to a large number of distributed brain regions. How the disease alters the functional topological organization of the brain, however, remains poorly understood. Furthermore, how levodopa modulates network topology in PD is largely unknown. The objective of this study was to use resting-state functional MRI and graph theory to determine how small-world architecture is altered in PD and affected by levodopa administration. Twenty-one PD patients and 20 controls underwent functional MRI scanning. PD patients were scanned off medication and 1 hour after 200 mg levodopa. Imaging data were analyzed using 226 nodes comprising 10 intrinsic brain networks. Correlation matrices were generated for each subject and converted into cost-thresholded, binarized adjacency matrices. Cost-integrated whole-brain global and local efficiencies were compared across groups and tested for relationships with disease duration and severity. Data from 2 patients and 4 controls were excluded because of excess motion. Patients off medication showed no significant changes in global efficiency and overall local efficiency, but in a subnetwork analysis did show increased local efficiency in executive (P = 0.006) and salience (P = 0.018) networks. Levodopa significantly decreased local efficiency (P = 0.039) in patients except within the subcortical network, in which it significantly increased local efficiency (P = 0.007). Levodopa modulates global and local efficiency measures of small-world topology in PD, suggesting that degeneration of nigrostriatal neurons in PD may be associated with a large-scale network reorganization and that levodopa tends to normalize the disrupted network topology in PD. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

Photovoltaic Module Reliability Workshop 2012: February 28 - March 1, 2012

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

The opportunity cost of time modulates cognitive effort.

PubMed

Otto, A Ross; Daw, Nathaniel D

2018-05-08

A spate of recent work demonstrates that humans seek to avoid the expenditure of cognitive effort, much like physical effort or economic resources. Less is clear, however, about the circumstances dictating how and when people decide to expend cognitive effort. Here we adopt a popular theory of opportunity costs and response vigor and to elucidate this question. This account, grounded in Reinforcement Learning, formalizes a trade-off between two costs: the harder work assumed necessary to emit faster actions and the opportunity cost inherent in acting more slowly (i.e., the delay that results to the next reward and subsequent rewards). Recent work reveals that the opportunity cost of time-operationalized as the average reward rate per unit time, theorized to be signaled by tonic dopamine levels, modulates the speed with which a person responds in a simple discrimination tasks. We extend this framework to cognitive effort in a diverse range of cognitive tasks, for which 1) the amount of cognitive effort demanded from the task varies from trial to trial and 2) the putative expenditure of cognitive effort holds measureable consequences in terms of accuracy and response time. In the domains of cognitive control, perceptual decision-making, and task-switching, we found that subjects tuned their level of effort exertion in accordance with the experienced average reward rate: when the opportunity cost of time was high, subjects made more errors and responded more quickly, which we interpret as a withdrawal of cognitive effort. That is, expenditure of cognitive effort appeared to be modulated by the opportunity cost of time. Further, and consistent with our account, the strength of this modulation was predicted by individual differences in efficacy of cognitive control. Taken together, our results elucidate the circumstances dictating how and when people expend cognitive effort. Copyright © 2018 Elsevier Ltd. All rights reserved.

Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Newmarker, Marc; Campbell, Mark

2012-03-16

Design, validate at prototype level, and then demonstrate a full size, 800 MWht Thermal Energy Storage (TES) system based on Phase Changing Material (PCM) TES modules with round trip efficiency in excess of 93%. The PCM TES module would be the building block of a TES system which can be deployed at costs inline with the DOE benchmark of 2020. The development of a reliable, unsophisticated, modular, and scalable TES system designed to be massmanufactured utilizing advanced automated fabrication and assembly processes and field installed in the most cost-effective configuration could facilitate the attainment of a Levelized Cost of Energymore » (LCOE) of $.07/kWh by 2015. It was believed that the DOE targets can be attained by finding the best combinationTES module size, its optimal integration in the power cycle, and readily available PCM. Work under this project ultimately focused on the development and performance evaluation of a 100kWht prototype heat exchanger. The design utilizes a commercially available heat exchanger product to create a unique latent heat PCM storage module. The novel ideal associated with this technology is the inclusion of an agitation mechanism that is activated during the discharge process to improve heat transfer. The prototype unit did not meet the performance goals estimated through modeling, nor did the estimated costs of the system fall in line with the goals established by DOE.« less

An economic analysis of conservative management versus active treatment for men with localized prostate cancer.

PubMed

Perlroth, Daniella J; Bhattacharya, Jay; Goldman, Dana P; Garber, Alan M

2012-12-01

Comparative effectiveness research suggests that conservative management (CM) strategies are no less effective than active initial treatment for many men with localized prostate cancer. We estimate longer-term costs of initial management strategies and potential US health expenditure savings by increased use of conservative management for men with localized prostate cancer. Five-year total health expenditures attributed to initial management strategies for localized prostate cancer were calculated using commercial claims data from 1998 to 2006, and savings were estimated from a US population health-care expenditure model. Our analysis finds that patients receiving combinations of active treatments have the highest additional costs over conservative management at $63 500, followed by $48 550 for intensity-modulated radiation therapy, $37 500 for primary androgen deprivation therapy, and $28 600 for brachytherapy. Radical prostatectomy ($15 200) and external beam radiation therapy ($18 900) were associated with the lowest costs. The population model estimated that US health expenditures could be lowered by 1) use of initial CM over all active treatment ($2.9-3.25 billion annual savings), 2) shifting patients receiving intensity-modulated radiation therapy to CM ($680-930 million), 3) foregoing primary androgen deprivation therapy($555 million), 4) reducing the use of adjuvant androgen deprivation in addition to local therapies ($630 million), and 5) using single treatments rather than combination local treatment ($620-655 million). In conclusion, we find that all active treatments are associated with higher longer-term costs than CM. Substantial savings, representing up to 30% of total costs, could be realized by adopting CM strategies, including active surveillance, for initial management of men with localized prostate cancer.

A Decentralized Wireless Solution to Monitor and Diagnose PV Solar Module Performance Based on Symmetrized-Shifted Gompertz Functions

PubMed Central

Molina-García, Angel; Campelo, José Carlos; Blanc, Sara; Serrano, Juan José; García-Sánchez, Tania; Bueso, María C.

2015-01-01

This paper proposes and assesses an integrated solution to monitor and diagnose photovoltaic (PV) solar modules based on a decentralized wireless sensor acquisition system. Both DC electrical variables and environmental data are collected at PV module level using low-cost and high-energy efficiency node sensors. Data is real-time processed locally and compared with expected PV module performances obtained by a PV module model based on symmetrized-shifted Gompertz functions (as previously developed and assessed by the authors). Sensor nodes send data to a centralized sink-computing module using a multi-hop wireless sensor network architecture. Such integration thus provides extensive analysis of PV installations, and avoids off-line tests or post-processing processes. In comparison with previous approaches, this solution is enhanced with a low-cost system and non-critical performance constraints, and it is suitable for extensive deployment in PV power plants. Moreover, it is easily implemented in existing PV installations, since no additional wiring is required. The system has been implemented and assessed in a Spanish PV power plant connected to the grid. Results and estimations of PV module performances are also included in the paper. PMID:26230694

A Decentralized Wireless Solution to Monitor and Diagnose PV Solar Module Performance Based on Symmetrized-Shifted Gompertz Functions.

PubMed

Molina-García, Angel; Campelo, José Carlos; Blanc, Sara; Serrano, Juan José; García-Sánchez, Tania; Bueso, María C

2015-07-29

This paper proposes and assesses an integrated solution to monitor and diagnose photovoltaic (PV) solar modules based on a decentralized wireless sensor acquisition system. Both DC electrical variables and environmental data are collected at PV module level using low-cost and high-energy efficiency node sensors. Data is real-time processed locally and compared with expected PV module performances obtained by a PV module model based on symmetrized-shifted Gompertz functions (as previously developed and assessed by the authors). Sensor nodes send data to a centralized sink-computing module using a multi-hop wireless sensor network architecture. Such integration thus provides extensive analysis of PV installations, and avoids off-line tests or post-processing processes. In comparison with previous approaches, this solution is enhanced with a low-cost system and non-critical performance constraints, and it is suitable for extensive deployment in PV power plants. Moreover, it is easily implemented in existing PV installations, since no additional wiring is required. The system has been implemented and assessed in a Spanish PV power plant connected to the grid. Results and estimations of PV module performances are also included in the paper.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Repins, Ingrid; Jordan, Dirk; Bosco, Nick

The proposed new IEC standard will address the test temperature requirements in IEC 61215 (module design), IEC 61730 (module safety), IEC 62790 (junction box safety) and IEC 62852 (connectors), and will provide guidelines to modify temperature limits in four existing standards to better describe module performance in hotter climates. This workshop includes four presentations: Special Testing for Modules Deployed in Hot Use Environments - Are We Doing This in a Low-Cost Way?, Experimental Evidence, Why the highest temperatures are the most stressful to PV modules during thermal cycling, and Safety Aspects for Modules Deployed in Hot Use Environments.

Scalable Light Module for Low-Cost, High-Efficiency Light- Emitting Diode Luminaires

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tarsa, Eric

2015-08-31

During this two-year program Cree developed a scalable, modular optical architecture for low-cost, high-efficacy light emitting diode (LED) luminaires. Stated simply, the goal of this architecture was to efficiently and cost-effectively convey light from LEDs (point sources) to broad luminaire surfaces (area sources). By simultaneously developing warm-white LED components and low-cost, scalable optical elements, a high system optical efficiency resulted. To meet program goals, Cree evaluated novel approaches to improve LED component efficacy at high color quality while not sacrificing LED optical efficiency relative to conventional packages. Meanwhile, efficiently coupling light from LEDs into modular optical elements, followed by optimallymore » distributing and extracting this light, were challenges that were addressed via novel optical design coupled with frequent experimental evaluations. Minimizing luminaire bill of materials and assembly costs were two guiding principles for all design work, in the effort to achieve luminaires with significantly lower normalized cost ($/klm) than existing LED fixtures. Chief project accomplishments included the achievement of >150 lm/W warm-white LEDs having primary optics compatible with low-cost modular optical elements. In addition, a prototype Light Module optical efficiency of over 90% was measured, demonstrating the potential of this scalable architecture for ultra-high-efficacy LED luminaires. Since the project ended, Cree has continued to evaluate optical element fabrication and assembly methods in an effort to rapidly transfer this scalable, cost-effective technology to Cree production development groups. The Light Module concept is likely to make a strong contribution to the development of new cost-effective, high-efficacy luminaries, thereby accelerating widespread adoption of energy-saving SSL in the U.S.« less

Autism Tendencies and Psychosis Proneness Interactively Modulate Saliency Cost.

PubMed

Abu-Akel, Ahmad; Apperly, Ian A; Wood, Stephen J; Hansen, Peter C; Mevorach, Carmel

2017-01-01

Atypical responses to salient information are a candidate endophenotype for both autism and psychosis spectrum disorders. The present study investigated the costs and benefits of such atypicalities for saliency-based selection in a large cohort of neurotypical adults in whom both autism and psychosis expressions were assessed. Two experiments found that autism tendencies and psychosis proneness interactively modulated the cost incurred in the presence of a task-irrelevant salient distractor. Specifically, expressions of autism and psychosis had opposing effects on responses to salient information such that the benefits associated with high expressions for autism offset costs associated with high expressions for psychosis. The opposing influences observed on saliency cost may be driven by distinct attentional mechanisms that are differentially affected by expressions for autism and psychosis. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Ecology of Flows and Drift Wave Turbulence: Reduced Models and Applications

NASA Astrophysics Data System (ADS)

Huang, Wen-Hsi

A major obstacle to sustainable solar technologies is end-of-life solar modules. In this thesis, a recycling process is proposed for crystalline-Si solar modules. It is a three-step process to break down Si modules and recover various materials. Over 95% of a module by weight can be recovered with this process. Two new technologies are demonstrated to enable the proposed recycling process. One is sequential electrowinning which allows multiple metals to be recovered one by one from Si modules, Ag, Pb, Sn and Cu. The other is sheet resistance monitoring by the 4-point probe which maximizes the amount of solar-grade Si recovered from Si modules with high throughput. The purity of the recovered metals is above 99% and the recovery rate can achieve between 70 80%. The recovered Si meets the specifications for solar-grade Si and at least 91% of Si from c-Si solar cells can be recovered. The recovered Si and metals are new feedstocks to the solar industry and generate over $12/module in revenue. This revenue enables a profitable recycling business for Si modules without any government support. The chemicals for recycling are carefully selected to minimize their environmental impact and also the cost. A network for collecting end-of-life solar modules is proposed based on the current distribution network for solar modules to contain the collection cost. As a result, the proposed recycling process for c-Si modules is technically, environmentally and financially sustainable.

Membrane Process to Capture CO{sub 2} from Coal-Fired Power Plant Flue Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Merkel, Tim; Wei, Xiaotong; Firat, Bilgen

2012-03-31

This final report describes work conducted for the U.S. Department of Energy National Energy Technology Laboratory (DOE NETL) on development of an efficient membrane process to capture carbon dioxide (CO{sub 2}) from power plant flue gas (award number DE-NT0005312). The primary goal of this research program was to demonstrate, in a field test, the ability of a membrane process to capture up to 90% of CO{sub 2} in coal-fired flue gas, and to evaluate the potential of a full-scale version of the process to perform this separation with less than a 35% increase in the levelized cost of electricity (LCOE).more » Membrane Technology and Research (MTR) conducted this project in collaboration with Arizona Public Services (APS), who hosted a membrane field test at their Cholla coal-fired power plant, and the Electric Power Research Institute (EPRI) and WorleyParsons (WP), who performed a comparative cost analysis of the proposed membrane CO{sub 2} capture process. The work conducted for this project included membrane and module development, slipstream testing of commercial-sized modules with natural gas and coal-fired flue gas, process design optimization, and a detailed systems and cost analysis of a membrane retrofit to a commercial power plant. The Polaris? membrane developed over a number of years by MTR represents a step-change improvement in CO{sub 2} permeance compared to previous commercial CO{sub 2}-selective membranes. During this project, membrane optimization work resulted in a further doubling of the CO{sub 2} permeance of Polaris membrane while maintaining the CO{sub 2}/N{sub 2} selectivity. This is an important accomplishment because increased CO{sub 2} permeance directly impacts the membrane skid cost and footprint: a doubling of CO{sub 2} permeance halves the skid cost and footprint. In addition to providing high CO{sub 2} permeance, flue gas CO{sub 2} capture membranes must be stable in the presence of contaminants including SO{sub 2}. Laboratory tests showed no degradation in Polaris membrane performance during two months of continuous operation in a simulated flue gas environment containing up to 1,000 ppm SO{sub 2}. A successful slipstream field test at the APS Cholla power plant was conducted with commercialsize Polaris modules during this project. This field test is the first demonstration of stable performance by commercial-sized membrane modules treating actual coal-fired power plant flue gas. Process design studies show that selective recycle of CO{sub 2} using a countercurrent membrane module with air as a sweep stream can double the concentration of CO{sub 2} in coal flue gas with little energy input. This pre-concentration of CO{sub 2} by the sweep membrane reduces the minimum energy of CO{sub 2} separation in the capture unit by up to 40% for coal flue gas. Variations of this design may be even more promising for CO{sub 2} capture from NGCC flue gas, in which the CO{sub 2} concentration can be increased from 4% to 20% by selective sweep recycle. EPRI and WP conducted a systems and cost analysis of a base case MTR membrane CO{sub 2} capture system retrofitted to the AEP Conesville Unit 5 boiler. Some of the key findings from this study and a sensitivity analysis performed by MTR include: The MTR membrane process can capture 90% of the CO{sub 2} in coal flue gas and produce high-purity CO{sub 2} (>99%) ready for sequestration. CO{sub 2} recycle to the boiler appears feasible with minimal impact on boiler performance; however, further study by a boiler OEM is recommended. For a membrane process built today using a combination of slight feed compression, permeate vacuum, and current compression equipment costs, the membrane capture process can be competitive with the base case MEA process at 90% CO{sub 2} capture from a coal-fired power plant. The incremental LCOE for the base case membrane process is about equal to that of a base case MEA process, within the uncertainty in the analysis. With advanced membranes (5,000 gpu for CO{sub 2} and 50 for CO{sub 2}/N{sub 2}), operating with no feed compression and low-cost CO{sub 2} compression equipment, an incremental LCOE of $33/MWh at 90% capture can be achieved (40% lower than the advanced MEA case). Even with lower cost compression, it appears unlikely that a membrane process using high feed compression (>5 bar) can be competitive with amine absorption, due to the capital cost and energy consumption of this equipment. Similarly, low vacuum pressure (<0.2 bar) cannot be used due to poor efficiency and high cost of this equipment. High membrane permeance is important to reduce the capital cost and footprint of the membrane unit. CO{sub 2}/N{sub 2} selectivity is less important because it is too costly to generate a pressure ratio where high selectivity can be useful. A potential cost ?sweet spot? exists for use of membrane-based technology, if 50-70% CO{sub 2} capture is acceptable. There is a minimum in the cost of CO{sub 2} avoided/ton that membranes can deliver at 60% CO{sub 2} capture, which is 20% lower than the cost at 90% capture. Membranes operating with no feed compression are best suited for lower capture rates. Currently, it appears that the biggest hurdle to use of membranes for post-combustion CO{sub 2} capture is compression equipment cost. An alternative approach is to use sweep membranes in parallel with another CO{sub 2} capture technology that does not require feed compression or vacuum equipment. Hybrid designs that utilize sweep membranes for selective CO{sub 2} recycle show potential to significantly reduce the minimum energy of CO{sub 2} separation.« less

A low-cost, tunable laser lock without laser frequency modulation

NASA Astrophysics Data System (ADS)

Shea, Margaret E.; Baker, Paul M.; Gauthier, Daniel J.

2015-05-01

Many experiments in optical physics require laser frequency stabilization. This can be achieved by locking to an atomic reference using saturated absorption spectroscopy. Often, the laser frequency is modulated and phase sensitive detection used. This method, while well-proven and robust, relies on expensive components, can introduce an undesirable frequency modulation into the laser, and is not easily frequency tuned. Here, we report a simple locking scheme similar to those implemented previously. We modulate the atomic resonances in a saturated absorption setup with an AC magnetic field created by a single solenoid. The same coil applies a DC field that allows tuning of the lock point. We use an auto-balanced detector to make our scheme more robust against laser power fluctuations and stray magnetic fields. The coil, its driver, and the detector are home-built with simple, cheap components. Our technique is low-cost, simple to setup, tunable, introduces no laser frequency modulation, and only requires one laser. We gratefully acknowledge the financial support of the NSF through Grant # PHY-1206040.

Heatpipe power system and heatpipe bimodal system design and development options

NASA Technical Reports Server (NTRS)

Houts, M. G.; Poston, D. I.; Emrich, W. J., Jr.

1997-01-01

The Heatpipe Power System (HPS) is a potential, near-term, low-cost space fission power system. The Heatpipe Bimodal System (HBS) is a potential, near-term, low-cost space fission power and/or propulsion system. Both systems will be composed of independent modules, and all components operate within the existing databases. The HPS and HBS have relatively few system integration issues; thus, the successful development of a module is a significant step toward verifying system feasibility and performance estimates. A prototypic HPS module is being fabricated, and testing is scheduled to begin in November 1996. A successful test will provide high confidence that the HPS can achieve its predicted performance.

A novel 6-DOF parallel robot and its pose errors compensation

NASA Astrophysics Data System (ADS)

Shi, Zhixin; Ye, Meiyan; Luo, Yufeng

2011-10-01

In the traditional security solution conditions, software firewall cannot intercept and respond the invasion before being attacked. And because of the high cost, the hardware firewall does not apply to the security strategy of the end nodes, so we have designed a kind of solution of embedded firewall with hardware and software. With ARM embedding Linux operating system, we have designed packet filter module and intrusion detection module to implement the basic function of firewall. Experiments and results show that that firewall has the advantages of low cost, high processing speed, high safety and the application of the computer terminals. This paper focuses on packet filtering module design and implementation.

Prototyping Instruments for Chemical Laboratory Using Inexpensive Electronic Modules.

PubMed

Urban, Pawel L

2018-05-15

Open-source electronics and programming can augment chemical and biomedical research. Currently, chemists can choose from a broad range of low-cost universal electronic modules (microcontroller boards and single-board computers) and use them to assemble working prototypes of scientific tools to address specific experimental problems and to support daily research work. The learning time can be as short as a few hours, and the required budget is often as low as 50 USD. Prototyping instruments using low-cost electronic modules gives chemists enormous flexibility to design and construct customized instrumentation, which can reduce the delays caused by limited access to high-end commercial platforms. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Architectural Considerations of Fiber-Radio Millimeter-Wave Wireless Access Systems

NASA Astrophysics Data System (ADS)

Kitayama, Ken-Ichi

The architecture of fiber-radio mm-wave wireless access systems critically depends upon the optical mm-wave generation and transport techniques. Four optical mm-wave generation and transport techniques: 1) optical self-heterodyning, 2) external modulation, 3) up- and downconversion, and 4) optical transceiver, will be assessed. From the technical viewpoints, their advantages and disadvantages are discussed. The economical assessment, focusing on the cost of a base station BS ( ), will suggest that the optical transceiver looks the most promising in the long run, but in the near future, however, the external modulation will be cost-effective. The experimental results of 60 GHz testbeds using the external modulation will support the conclusion.

Compact Modules for Wireless Communication Systems in the E-Band (71-76 GHz)

NASA Astrophysics Data System (ADS)

Montero-de-Paz, Javier; Oprea, Ion; Rymanov, Vitaly; Babiel, Sebastian; García-Muñoz, Luis Enrique; Lisauskas, Alvydas; Hoefle, Matthias; Jimenez, Álvaro; Cojocari, Oleg; Segovia-Vargas, Daniel; Palandöken, Merih; Tekin, Tolga; Stöhr, Andreas; Carpintero, Guillermo

2013-04-01

The millimeter-wave spectrum above 70 GHz provides a cost-effective solution to increase the wireless communications data rates by increasing the carrier wave frequencies. We report on the development of two key components of a wireless transmission system, a high-speed photodiode (HS-PD) and a Schottky Barrier Diode (SBD). Both components operate uncooled, a key issue in the development of compact modules. On the transmitter side, an improved design of the HS-PD allows it to deliver an output RF power exceeding 0 dBm (1 mW). On the receiver side, we present the design process and achieved results on the development of a compact direct envelope detection receiver based on a quasi-optical SDB module. Different resonant (meander dipole) and broadband (Log-Spiral and Log-Periodic) planar antenna solutions are designed, matching the antenna and Schottky diode impedances at high frequency. Impedance matching at baseband is also provided by means of an impedance transition to a 50 Ohm output. From this comparison, we demonstrate the excellent performance of the broadband antennas over the entire E-band by setting up a short-range wireless link transmitting a 1 Gbps data signal.

Implementation and validation of an economic module in the Be-FAST model to predict costs generated by livestock disease epidemics: Application to classical swine fever epidemics in Spain.

PubMed

Fernández-Carrión, E; Ivorra, B; Martínez-López, B; Ramos, A M; Sánchez-Vizcaíno, J M

2016-04-01

Be-FAST is a computer program based on a time-spatial stochastic spread mathematical model for studying the transmission of infectious livestock diseases within and between farms. The present work describes a new module integrated into Be-FAST to model the economic consequences of the spreading of classical swine fever (CSF) and other infectious livestock diseases within and between farms. CSF is financially one of the most damaging diseases in the swine industry worldwide. Specifically in Spain, the economic costs in the two last CSF epidemics (1997 and 2001) reached jointly more than 108 million euros. The present analysis suggests that severe CSF epidemics are associated with significant economic costs, approximately 80% of which are related to animal culling. Direct costs associated with control measures are strongly associated with the number of infected farms, while indirect costs are more strongly associated with epidemic duration. The economic model has been validated with economic information around the last outbreaks in Spain. These results suggest that our economic module may be useful for analysing and predicting economic consequences of livestock disease epidemics. Copyright © 2016 Elsevier B.V. All rights reserved.

Terrestrial solar cell module automated array assembly, task 4

NASA Technical Reports Server (NTRS)

1978-01-01

A cost effective design and manufacturing process which would produce solar cell modules capable of meeting qualification test criteria was developed. Emphasis was placed on the development of an aluminum paste back contact process.

Employment of sawtooth-shaped-function excitation signal and oversampling for improving resistance measurement accuracy

NASA Astrophysics Data System (ADS)

Lin, Ling; Li, Shujuan; Yan, Wenjuan; Li, Gang

2016-10-01

In order to achieve higher measurement accuracy of routine resistance without increasing the complexity and cost of the system circuit of existing methods, this paper presents a novel method that exploits a shaped-function excitation signal and oversampling technology. The excitation signal source for resistance measurement is modulated by the sawtooth-shaped-function signal, and oversampling technology is employed to increase the resolution and the accuracy of the measurement system. Compared with the traditional method of using constant amplitude excitation signal, this method can effectively enhance the measuring accuracy by almost one order of magnitude and reduce the root mean square error by 3.75 times under the same measurement conditions. The results of experiments show that the novel method can attain the aim of significantly improve the measurement accuracy of resistance on the premise of not increasing the system cost and complexity of the circuit, which is significantly valuable for applying in electronic instruments.

An overview of the value of parabolic dish solar thermal systems in industrial cogeneration applications

NASA Technical Reports Server (NTRS)

1982-01-01

The essential elements of the cogeneration system configuration to be captured were the displacement of thermal energy by collection and use of the Brayton exhaust stream, and the sale back to the utility of any electricity production in excess of on-site requirements. In contrast to simply dumping these energy flows, their use or sale obviously serves, by itself, to increase gross value of the solar thermal energy system. Net allowable cost of the parabolic dish modules may or may not be increased, however. A consideration is that the waste heat capture and delivery subsystems are not free. This study does not address the incremental cost of adding waste heat capture, transport, and conversion (to steam, if necessary). It does compute a value for the thermal energy thereby displaced. This value can serve as a first-round input to any detailed economic evaluation of waste heat recovery.

47 CFR 32.2231 - Radio systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... costs. This account shall also include the original cost of earth stations and spare parts, material or..., amplification, propagation, reception, modulation, and demodulation of radio waves in free space over which...

Progress and challenges for cost effective kerfless Silicon crystal growth for PV application

NASA Astrophysics Data System (ADS)

Serra, J. M.; Alves, J. Maia; Vallera, A. M.

2017-06-01

The major barrier for PV penetration is cost. And the single most important cost factor in silicon technology is the wafer (≈35% of the module cost). Although tremendous progress on cell processing has been reported in recent years, a much smaller evolution is seen on what should be the key point to address - the wafer. The ingot-slicing process is reaching its limits as the wafer thickness is reduced in an effort to lower material costs. Kerf losses of ≈50% and an increase in breakage of a high value added material are putting a lower bound to this approach. New ideas are therefore needed for producing wafers in a way to overcome these limitations. In this paper we present three new concepts being developed in our laboratory that have one thing in common: they all are zero kerf loss processes, aiming at significant reductions in material loss. One explores the concept of exfoliation, the other two aim at the growth of silicon directly into ribbons. These were conceived as continuous processes, based on a floating molten zone concept, to avoid impurity contamination during crystallization.

Model for Increasing the Power Obtained from a Thermoelectric Generator Module

NASA Astrophysics Data System (ADS)

Huang, Gia-Yeh; Hsu, Cheng-Ting; Yao, Da-Jeng

2014-06-01

We have developed a model for finding the most efficient way of increasing the power obtained from a thermoelectric generator (TEG) module with a variety of operating conditions and limitations. The model is based on both thermoelectric principles and thermal resistance circuits, because a TEG converts heat into electricity consistent with these two theories. It is essential to take into account thermal contact resistance when estimating power generation. Thermal contact resistance causes overestimation of the measured temperature difference between the hot and cold sides of a TEG in calculation of the theoretical power generated, i.e. the theoretical power is larger than the experimental power. The ratio of the experimental open-loop voltage to the measured temperature difference, the effective Seebeck coefficient, can be used to estimate the thermal contact resistance in the model. The ratio of the effective Seebeck coefficient to the theoretical Seebeck coefficient, the Seebeck coefficient ratio, represents the contact conditions. From this ratio, a relationship between performance and different variables can be developed. The measured power generated by a TEG module (TMH400302055; Wise Life Technology, Taiwan) is consistent with the result obtained by use of the model; the relative deviation is 10%. Use of this model to evaluate the most efficient means of increasing the generated power reveals that the TEG module generates 0.14 W when the temperature difference is 25°C and the Seebeck coefficient ratio is 0.4. Several methods can be used triple the amount of power generated. For example, increasing the temperature difference to 43°C generates 0.41 W power; improving the Seebeck coefficient ratio to 0.65 increases the power to 0.39 W; simultaneously increasing the temperature difference to 34°C and improving the Seebeck coefficient ratio to 0.5 increases the power to 0.41 W. Choice of the appropriate method depends on the limitations of system, the cost, and the environment.

Analyzing the Energy Performance, Wind Loading, and Costs of Photovoltaic Slat Modules on Commercial Rooftops

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Geet, Otto D.; Fu, Ran; Horowitz, Kelsey A.

NREL studied a new type of photovoltaic (PV) module configuration wherein multiple narrow, tilted slats are mounted in a single frame. Each slat of the PV slat module contains a single row of cells and is made using ordinary crystalline silicon PV module materials and processes, including a glass front sheet and weatherproof polymer encapsulation. Compared to a conventional ballasted system, a system using slat modules offer higher energy production and lower weight at lower LCOE. The key benefits of slat modules are reduced wind loading, improved capacity factor and reduced installation cost. First, the individual slats allow air tomore » flow through, which reduce wind loading. Using PV performance modeling software, we compared the performance of an optimized installation of slats modules to a typical installation of conventional modules in a ballasted rack mounting system. Based on the results of the performance modeling two different row tilt and spacing were tested in a wind tunnel. Scaled models of the PV Slat modules were wind tunnel tested to quantify the wind loading of a slat module system on a commercial rooftop, comparing the results to conventional ballasted rack mounted PV modules. Some commercial roofs do not have sufficient reserve dead load capacity to accommodate a ballasted system. A reduced ballast system design could make PV system installation on these roofs feasible for the first time without accepting the disadvantages of penetrating mounts. Finally, technoeconomic analysis was conducted to enable an economic comparison between a conventional commercial rooftop system and a reduced-ballast slat module installation.« less

Experimental elaboration and analysis of dye-sensitized TiO2 solar cells (DSSC) dyed by natural dyes and conductive polymers

NASA Astrophysics Data System (ADS)

KałuŻyński, P.; Maciak, E.; Herzog, T.; Wójcik, M.

2016-09-01

In this paper we propose low cost and easy in development fully working dye-sensitized solar cell module made with use of a different sensitizing dyes (various anthocyanins and P3HT) for increasing the absorption spectrum, transparent conducting substrates (vaccum spattered chromium and gold), nanometer sized TiO2 film, iodide and methyl viologen dichloride based electrolyte, and a counter electrode (vaccum spattered platinum or carbon). Moreover, some of the different technologies and optimization manufacturing processes were elaborated for energy efficiency increase and were presented in this paper.

InGaAlAs RW-based electro-absorption-modulated DFB-lasers for high-speed applications

NASA Astrophysics Data System (ADS)

Moehrle, Martin; Klein, Holger; Bornholdt, Carsten; Przyrembel, Georges; Sigmund, Ariane; Molzow, Wolf-Dietrich; Troppenz, Ute; Bach, Heinz-Gunter

2014-05-01

Electro-absorption modulated 10G and 25G DFB lasers (EML) are key components in transmission systems for long reach (up to 10 km) and extended reach (up to 80 km) applications. The next generation Ethernet will most likely be 400 Gb/s which will require components with even higher bandwidth. Commercially available EMLs are regarded as high-cost components due to their separate epitaxial butt-coupling growth process to separately optimize the DFB laser and the electro-absorption modulator (EAM). Alternatively the selective area growth (SAG) technique is used to achieve different MQW bandgaps in the DFB and EAM section of an EML. However for a lot of applications an emission wavelength within a narrow wavelength window is required enforcing a temperature controlled operation. All these applications can be covered with the developed EML devices that use a single InGaAlAs MQW waveguide for both the DFB and the EAM enabling a low-cost fabrication process similar to a conventional DFB laser diode. It will be shown that such devices can be used for 25Gb/s and 40Gb/s applications with excellent performance. By an additional monolithic integration of an impedance matching circuit the module fabrication costs can be reduced but also the modulation bandwidth of the devices can be further enhanced. Up to 70Gb/s modulation with excellent eye openings can be achieved. This novel approach opens the possibility for 100Gb/s NRZ EMLs and thus 4x100Gb/s NRZ EML-based transmitters in future. Also even higher bitrates seem feasible using more complex modulation formats such as e.g. DMT and PAM.

Clinical services provided by staff pharmacists in a community hospital.

PubMed

Garrelts, J C; Smith, D F

1990-09-01

A program for developing staff pharmacists' clinical skills and documenting pharmacists' clinical interventions in a large community teaching hospital is described. A coordinator hired in 1984 to develop clinical pharmacy services began a didactic and experiential program for baccalaureate-level staff pharmacists. Fourteen educational modules are supplemented by journal and textbook articles and small-group discussions of clinical cases, and the clinical coordinator provides individual training on the patient-care units for each pharmacist. Monitoring of clinical pharmacy services began in June 1987; each intervention provided by a pharmacist is recorded on a specially designed form. A target-drug program is used to document cost avoidance achieved through clinical services. Information collected through these monitoring activities is used to educate the pharmacy staff, shared with the pharmacy and therapeutics committee, and used to monitor prescribing patterns of individual physicians. The data are used in the hospital's productivity-monitoring system. All pharmacists who were on staff in 1984 have completed the educational modules, and all new employees are in the process. Since monitoring began, the number of clinical interventions has averaged 2098 per month. Cost avoidance has averaged $9306 per month. Over a five-year period, the development of staff pharmacists' clinical services raised the level of professional practice, produced substantial cost avoidance, and increased the number of pharmacist interventions in medication use.

Dynamic Accuracy of Inertial Magnetic Sensor Modules

DTIC Science & Technology

2016-12-01

and the cost of the YEI 3-space data-logging sensor was justified. C. PREVIOUS WORK In [7], Jeremy Cookson built a low-cost pendulum with an optical...encoder to test the dynamic accuracy of MARG sensor modules. The pendulum was designed in order to execute dynamic, repeatable tests in a single...3DM-GX1 and 3DM-GX3-25 sensors. In [8], Leslie Landry developed similar repeatable tests and utilized the pendulum to test the dynamic accuracy of

High Efficiency Solar Integrated Roof Membrane Product

DOE Office of Scientific and Technical Information (OSTI.GOV)

Partyka, Eric; Shenoy, Anil

2013-05-15

This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.

OpCost: an open-source system for estimating costs of stand-level forest operations

Treesearch

Conor K. Bell; Robert F. Keefe; Jeremy S. Fried

2017-01-01

This report describes and documents the OpCost forest operations cost model, a key component of the BioSum analysis framework. OpCost is available in two editions: as a callable module for use with BioSum, and in a stand-alone edition that can be run directly from R. OpCost model logic and assumptions for this open-source tool are explained, references to the...

Adoption of Hypofractionated Radiation Therapy for Breast Cancer After Publication of Randomized Trials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jagsi, Reshma, E-mail: rjagsi@med.umich.edu; Falchook, Aaron D.; Hendrix, Laura H.

2014-12-01

Purpose: Large randomized trials have established the noninferiority of shorter courses of “hypofractionated” radiation therapy (RT) to the whole breast compared to conventional courses using smaller daily doses in the adjuvant treatment of selected breast cancer patients undergoing lumpectomy. Hypofractionation is more convenient and less costly. Therefore, we sought to determine uptake of hypofractionated breast RT over time. Methods and Materials: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database, we identified 16,096 women with node-negative breast cancer and 4269 with ductal carcinoma in situ (DCIS) who received lumpectomy followed by more than 12 fractions of RT between 2004 andmore » 2010. Based on Medicare claims, we determined the number of RT treatments given and grouped patients into those receiving hypofractionation (13-24) or those receiving conventional fractionation (≥25). We also determined RT technique (intensity modulated RT or not) using Medicare claims. We evaluated patterns and correlates of hypofractionation receipt using bivariate and multivariable analyses. Results: Hypofractionation use was similar in patients with DCIS and those with invasive disease. Overall, the use of hypofractionation increased from 3.8% in 2006 to 5.4% in 2007, to 9.4% in 2008, and to 13.6% in 2009 and 2010. Multivariable analysis showed increased use of hypofractionation in recent years and in patients with older age, smaller tumors, increased comorbidity, higher regional education, and Western SEER regions. However, even in patients over the age of 80, the hypofractionation rate in 2009 to 2010 was only 25%. Use of intensity modulated RT (IMRT) also increased over time (from 9.4% in 2004 to 22.7% in 2009-2010) and did not vary significantly between patients receiving hypofractionation and those receiving traditional fractionation. Conclusions: Hypofractionation use increased among low-risk older US breast cancer patients with publication and maturation of evidence from randomized trials, but overall use of this cost-saving approach remained low. This contrasts with the more rapid rate of adoption of IMRT in the same time period, a costly innovation supported by less strong evidence of benefit.« less

Simulation, measurement, and emulation of photovoltaic modules using high frequency and high power density power electronic circuits

NASA Astrophysics Data System (ADS)

Erkaya, Yunus

The number of solar photovoltaic (PV) installations is growing exponentially, and to improve the energy yield and the efficiency of PV systems, it is necessary to have correct methods for simulation, measurement, and emulation. PV systems can be simulated using PV models for different configurations and technologies of PV modules. Additionally, different environmental conditions of solar irradiance, temperature, and partial shading can be incorporated in the model to accurately simulate PV systems for any given condition. The electrical measurement of PV systems both prior to and after making electrical connections is important for attaining high efficiency and reliability. Measuring PV modules using a current-voltage (I-V) curve tracer allows the installer to know whether the PV modules are 100% operational. The installed modules can be properly matched to maximize performance. Once installed, the whole system needs to be characterized similarly to detect mismatches, partial shading, or installation damage before energizing the system. This will prevent any reliability issues from the onset and ensure the system efficiency will remain high. A capacitive load is implemented in making I-V curve measurements with the goal of minimizing the curve tracer volume and cost. Additionally, the increase of measurement resolution and accuracy is possible via the use of accurate voltage and current measurement methods and accurate PV models to translate the curves to standard testing conditions. A move from mechanical relays to solid-state MOSFETs improved system reliability while significantly reducing device volume and costs. Finally, emulating PV modules is necessary for testing electrical components of a PV system. PV emulation simplifies and standardizes the tests allowing for different irradiance, temperature and partial shading levels to be easily tested. Proper emulation of PV modules requires an accurate and mathematically simple PV model that incorporates all known system variables so that any PV module can be emulated as the design requires. A non-synchronous buck converter is proposed for the emulation of a single, high-power PV module using traditional silicon devices. With the proof-of-concept working and improvements in efficiency, power density and steady-state errors made, dynamic tests were performed using an inverter connected to the PV emulator. In order to improve the dynamic characteristics, a synchronous buck converter topology is proposed along with the use of advanced GaNFET devices which resulted in very high power efficiency and improved dynamic response characteristics when emulating PV modules.

Development and Testing of a Power Trough System Using a Structurally-Efficient, High-Performance, Large-Aperture Concentrator with Thin Glass Reflector and Focal Point Rotation

DOE Office of Scientific and Technical Information (OSTI.GOV)

May, E. K.; Forristall, R.

2005-11-01

Industrial Solar Technology has assembled a team of experts to develop a large-aperture parabolic trough for the electric power market that moves beyond cost and operating limitations of 1980's designs based on sagged glass reflectors. IST's structurally efficient space frame design will require nearly 50% less material per square meter than a Solel LS-2 concentrator and the new trough will rotate around the focal point. This feature eliminates flexhoses that increase pump power, installation and maintenance costs. IST aims to deliver a concentrator module costing less than $100 per square meter that can produce temperatures up to 400 C. Themore » IST concentrator is ideally suited for application of front surface film reflectors and ensures that US corporations will manufacture major components, except for the high temperature receivers.« less

Editorial: Photovoltaic Materials and Devices 2014

DOE PAGES

Sopori, Bhushan; Rupnowski, Peter; Shet, Sudhakar; ...

2014-12-22

An ever increasing demand on energy has fostered many new generation technologies, which include photovoltaics. In recent years, photovoltaic industry has grown very rapidly. The installed capacity of PV for 2013 was about 37 GW and 2014 sales are expected to be around 45 GW. However, there has been excess production for last several years, which is responsible in part for the low prices (about 60 c/W). To lower the PV energy costs further, a major strategy appears to be going to high efficiency solar cells. This approach is favored (over lower cost/lower efficiency) because cell efficiency has a verymore » large influence on the acceptable manufacturing cost of a PV module. Hence, the PV industry is moving toward developing processes and equipment to manufacture solar cells that can yield efficiencies >20%. Therefore, further research is needed within existing technologies to accomplish these objectives. Likewise, research will continue to seek new materials and devices.« less

Modelling the cost of community interventions to reduce child mortality in South Africa using the Lives Saved Tool (LiST).

PubMed

Nkonki, Lungiswa Ll; Chola, Lumbwe L; Tugendhaft, Aviva A; Hofman, Karen K

2017-08-28

To estimate the costs and impact on reducing child mortality of scaling up interventions that can be delivered by community health workers at community level from a provider's perspective. In this study, we used the Lives Saved Tool (LiST), a module in the spectrum software. Within the spectrum software, LiST interacts with other modules, the AIDS Impact Module, Family Planning Module and Demography Projections Module (Dem Proj), to model the impact of more than 60 interventions that affect cause-specific mortality. DemProj Based on National South African Data. A total of nine interventions namely, breastfeeding promotion, complementary feeding, vitamin supplementation, hand washing with soap, hygienic disposal of children's stools, oral rehydration solution, oral antibiotics for the treatment of pneumonia, therapeutic feeding for wasting and treatment for moderate malnutrition. Reducing child mortality. A total of 9 interventions can prevent 8891 deaths by 2030. Hand washing with soap (21%) accounts for the highest number of deaths prevented, followed by therapeutic feeding (19%) and oral rehydration therapy (16%). The top 5 interventions account for 77% of all deaths prevented. At scale, an estimated cost of US$169.5 million (US$3 per capita) per year will be required in community health worker costs. The use of community health workers offers enormous opportunities for saving lives. These programmes require appropriate financial investments. Findings from this study show what can be achieved if concerted effort is channelled towards the identified set of life-saving interventions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Redesign of Glenn Research Center D1 Flywheel Module

NASA Technical Reports Server (NTRS)

Jansen, Ralph H.; Wagner, Robert C.; Duffy, Kirsten P.; Hervol, David S.; Storozuk, Ronald J.; Dever, Timothy P.; Anzalone, Salvatore M.; Trudell, Jeffrey J.; Konno, Kevin E.; Kenny, Andrew

2002-01-01

Glenn Research Center has completed the redesign of the D1 flywheel module. The redesign includes a new rotor with a composite rim, motor/generator, touchdown bearings, sensors, and a magnetic actuator. The purpose of the relatively low cost module upgrade is to enable it to continuously operate throughout its speed range of 0 to 60,000 RPM. The module will be used as part of a combined attitude control and bus regulation experiment.

Development of Low-Cost Remote-Control Generators Based on BiTe Thermoelectric Modules

NASA Astrophysics Data System (ADS)

Juanicó, Luis E.; Rinalde, Fabián; Taglialavore, Eduardo; Molina, Marcelo

2013-07-01

This paper presents a new thermogenerator based on moderate-temperature (up to 175°C) BiTe modules available on the open market. Despite this handicap relative to commercial thermogenerators based on high-temperature proprietary-technology PbBi modules (up to 560°C), this new design may become economically competitive due to its innovative thermal sink. Our thermal sink is based on a free-convection water loop built with standard tubing and household hot-water radiators, leading to a more practical, modular design. So, the specific cost of about 55,000 USD/kW obtained for this 120-W prototype is improved to 33,000 USD/kW for a 1-kW unit, which represents about half the price of commercial thermogenerators. Moreover, considering recently launched BiTe modules (that withstand up to 320°C), our proposition could have an even more favorable outlook.

Arbitrary-shaped Brillouin microwave photonic filter by manipulating a directly modulated pump.

PubMed

Wei, Wei; Yi, Lilin; Jaouën, Yves; Hu, Weisheng

2017-10-15

We present a cost-effective gigahertz-wide arbitrary-shaped microwave photonic filter based on stimulated Brillouin scattering in fiber using a directly modulated laser (DML). After analyzing the relationship between the spectral power density and the modulation current of the DML, we manage to precisely adjust the optical spectrum of the DML, thereby controlling the Brillouin filter response arbitrarily for the first time, to the best of our knowledge. The filter performance is evaluated by amplifying a 500 Mb/s non-return-to-zero on-off keying signal using a 1 GHz rectangular filter. The comparison between the proposed DML approach and the previous approach adopting a complex IQ modulator shows similar filter flexibility, shape fidelity, and noise performance, proving that the DML-based Brillouin filter technique is a cost-effective and valid solution for microwave photonic applications.

Quantifying Reliability - The Next Step for a Rapidly Maturing PV Industry and China's Role

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

2015-10-14

PV customers wish to know how long their PV modules will last, but quantitatively predicting service life is difficult because of the large number of ways that a module can fail, the variability of the use environment, the cost of the testing, and the short product development time, especially when compared with the long desired lifetime. China should play a key role in developing international standards because China manufactures most of the world's PV modules. The presentation will describe the steps that need to be taken to create a service life prediction within the context of a defined bill ofmore » materials, process window and use environment. Worldwide standards for cost-effective approaches to service-life predictions will be beneficial to both PV customers and manufacturers since the consequences of premature module failure can be disastrous for both.« less

Advances in polycrystalline thin-film photovoltaics for space applications

NASA Technical Reports Server (NTRS)

Lanning, Bruce R.; Armstrong, Joseph H.; Misra, Mohan S.

1994-01-01

Polycrystalline, thin-film photovoltaics represent one of the few (if not the only) renewable power sources which has the potential to satisfy the demanding technical requirements for future space applications. The demand in space is for deployable, flexible arrays with high power-to-weight ratios and long-term stability (15-20 years). In addition, there is also the demand that these arrays be produced by scalable, low-cost, high yield, processes. An approach to significantly reduce costs and increase reliability is to interconnect individual cells series via monolithic integration. Both CIS and CdTe semiconductor films are optimum absorber materials for thin-film n-p heterojunction solar cells, having band gaps between 0.9-1.5 ev and demonstrated small area efficiencies, with cadmium sulfide window layers, above 16.5 percent. Both CIS and CdTe polycrystalline thin-film cells have been produced on a laboratory scale by a variety of physical and chemical deposition methods, including evaporation, sputtering, and electrodeposition. Translating laboratory processes which yield these high efficiency, small area cells into the design of a manufacturing process capable of producing 1-sq ft modules, however, requires a quantitative understanding of each individual step in the process and its (each step) effect on overall module performance. With a proper quantification and understanding of material transport and reactivity for each individual step, manufacturing process can be designed that is not 'reactor-specific' and can be controlled intelligently with the design parameters of the process. The objective of this paper is to present an overview of the current efforts at MMC to develop large-scale manufacturing processes for both CIS and CdTe thin-film polycrystalline modules. CIS cells/modules are fabricated in a 'substrate configuration' by physical vapor deposition techniques and CdTe cells/modules are fabricated in a 'superstrate configuration' by wet chemical methods. Both laser and mechanical scribing operations are used to monolithically integrate (series interconnect) the individual cells into modules. Results will be presented at the cell and module development levels with a brief description of the test methods used to qualify these devices for space applications. The approach and development efforts are directed towards large-scale manufacturability of established thin-film, polycrystalline processing methods for large area modules with less emphasis on maximizing small area efficiencies.

Will we exceed 50% efficiency in photovoltaics?

NASA Astrophysics Data System (ADS)

Luque, Antonio

2011-08-01

Solar energy is the most abundant and reliable source of energy we have to provide for the multi-terawatt challenge we are facing. Although huge, this resource is relatively dispersed. High conversion efficiency is probably necessary for cost effectiveness. Solar cell efficiencies above 40% have been achieved with multijunction (MJ) solar cells. These achievements are here described. Possible paths for improvement are hinted at including third generation photovoltaics concepts. It is concluded that it is very likely that the target of 50% will eventually be achieved. This high efficiency requires operating under concentrated sunlight, partly because concentration helps increase the efficiency but mainly because the cost of the sophisticated cells needed can only be paid by extracting as much electric power form each cell as possible. The optical challenges associated with the concentrator optics and the tools for overcoming them, in particular non-imaging optics, are briefly discussed and the results and trends are described. It is probable that optical efficiency over 90% will be possible in the future. This would lead to a module efficiency of 45%. The manufacturing of a concentrator has to be addressed at three levels of integration: module, array, and photovoltaic (PV) subfield. The PV plant as a whole is very similar than a flat module PV plant with two-axes tracking. At the module level, the development of tools for easy manufacturing and quality control is an important topic. Furthermore, they can accommodate in different position cells with different spectral sensitivities so complementing the effort in manufacturing MJ cells. At the array level, a proper definition of the nameplate watts, since the diffuse light is not used, is under discussion. The cost of installation of arrays in the field can be very much reduced by self aligning tracking control strategies. At the subfield level, aspects such as the self shadowing of arrays causes the CPV subfields to be sparsely packed leading to a ground efficiency, in the range of 10%, that in some cases will be below that of fixed modules of much lower cell efficiency. All this taken into account, High Concentration PV (HCPV) has the opportunity to become the cheapest of the PV technologies and beat the prevalent electricity generation technologies. Of course the way will be paved with challenges, and success is not guaranteed.

Flat-plate solar array project. Volume 5: Process development

NASA Technical Reports Server (NTRS)

Gallagher, B.; Alexander, P.; Burger, D.

1986-01-01

The goal of the Process Development Area, as part of the Flat-Plate Solar Array (FSA) Project, was to develop and demonstrate solar cell fabrication and module assembly process technologies required to meet the cost, lifetime, production capacity, and performance goals of the FSA Project. R&D efforts expended by Government, Industry, and Universities in developing processes capable of meeting the projects goals during volume production conditions are summarized. The cost goals allocated for processing were demonstrated by small volume quantities that were extrapolated by cost analysis to large volume production. To provide proper focus and coverage of the process development effort, four separate technology sections are discussed: surface preparation, junction formation, metallization, and module assembly.

Reliability Evaluation of Concentrator Photovoltaic Modules per IEC Qualification Specifications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tamizhmani, Govindasamy

2012-12-05

This project is related to the qualification testing of new generation CPV (concentrator photovoltaics) modules at lower testing costs and lower turnaround time. In this project, the first testing program was completed for two CPV manufacturers, the second testing program was completed for two manufacturers at 65% of the actual testing cost and at less than 3 months of testing turnaround time and the third testing program was completed for two manufacturers at 65% of the actual testing cost and at less than 3 months of testing turnaround time. Due to their financial situation and restructuring, Amonix (one of themore » CPV manufacturers) intermittently terminated the test programs.« less

A Module Experimental Process System Development Unit (MEPSDU). [flat plate solar arrays

NASA Technical Reports Server (NTRS)

1981-01-01

The development of a cost effective process sequence that has the potential for the production of flat plate photovoltaic modules which meet the price goal in 1986 of 70 cents or less per Watt peak is described. The major accomplishments include (1) an improved AR coating technique; (2) the use of sand blast back clean-up to reduce clean up costs and to allow much of the Al paste to serve as a back conductor; and (3) the development of wave soldering for use with solar cells. Cells were processed to evaluate different process steps, a cell and minimodule test plan was prepared and data were collected for preliminary Samics cost analysis.

Experimental demonstration of using divergence cost-function in SPGD algorithm for coherent beam combining with tip/tilt control.

PubMed

Geng, Chao; Luo, Wen; Tan, Yi; Liu, Hongmei; Mu, Jinbo; Li, Xinyang

2013-10-21

A novel approach of tip/tilt control by using divergence cost function in stochastic parallel gradient descent (SPGD) algorithm for coherent beam combining (CBC) is proposed and demonstrated experimentally in a seven-channel 2-W fiber amplifier array with both phase-locking and tip/tilt control, for the first time to our best knowledge. Compared with the conventional power-in-the-bucket (PIB) cost function for SPGD optimization, the tip/tilt control using divergence cost function ensures wider correction range, automatic switching control of program, and freedom of camera's intensity-saturation. Homemade piezoelectric-ring phase-modulator (PZT PM) and adaptive fiber-optics collimator (AFOC) are developed to correct piston- and tip/tilt-type aberrations, respectively. The PIB cost function is employed for phase-locking via maximization of SPGD optimization, while the divergence cost function is used for tip/tilt control via minimization. An average of 432-μrad of divergence metrics in open loop has decreased to 89-μrad when tip/tilt control implemented. In CBC, the power in the full width at half maximum (FWHM) of the main lobe increases by 32 times, and the phase residual error is less than λ/15.

Distributed numerical controllers

NASA Astrophysics Data System (ADS)

Orban, Peter E.

2001-12-01

While the basic principles of Numerical Controllers (NC) have not changed much during the years, the implementation of NCs' has changed tremendously. NC equipment has evolved from yesterday's hard-wired specialty control apparatus to today's graphics intensive, networked, increasingly PC based open systems, controlling a wide variety of industrial equipment with positioning needs. One of the newest trends in NC technology is the distributed implementation of the controllers. Distributed implementation promises to offer robustness, lower implementation costs, and a scalable architecture. Historically partitioning has been done along the hierarchical levels, moving individual modules into self contained units. The paper discusses various NC architectures, the underlying technology for distributed implementation, and relevant design issues. First the functional requirements of individual NC modules are analyzed. Module functionality, cycle times, and data requirements are examined. Next the infrastructure for distributed node implementation is reviewed. Various communication protocols and distributed real-time operating system issues are investigated and compared. Finally, a different, vertical system partitioning, offering true scalability and reconfigurability is presented.

An Interactive Real-time Decision Support System for Leachate Irrigation on Evapotranspiration Landfill Covers

NASA Astrophysics Data System (ADS)

Wang, Y.

2015-12-01

Landfill disposal is still the most common and economical practice for municipal solid waste in most countries. However, heavily polluted leachate generated by excess rainwater percolating through the landfill waste is the major drawback of this practice. Evapotranspiration (ET) cover systems are increasingly being used as alternative cover systems to minimize percolation by evapotranspiration. Leachate recirculation is one of the least expensive options for leachate treatment. The combination of ET cover systems and leachate recirculation can be an economical and environment-friendly practice for landfill leachate management. An interactive real-time decision support system is being developed to better manage leachate irrigation using historical and forecasting weather data, and real time soil moisture data. The main frame of this system includes soil water modules, and plant-soil modules. An inverse simulation module is also included to calibrate certain parameters based on observed data when necessary. It would be an objectives-oriented irrigation management tool to minimize landfill operation costs and negative environmental impacts.

Synchronous acquisition of multi-channel signals by single-channel ADC based on square wave modulation

NASA Astrophysics Data System (ADS)

Yi, Xiaoqing; Hao, Liling; Jiang, Fangfang; Xu, Lisheng; Song, Shaoxiu; Li, Gang; Lin, Ling

2017-08-01

Synchronous acquisition of multi-channel biopotential signals, such as electrocardiograph (ECG) and electroencephalograph, has vital significance in health care and clinical diagnosis. In this paper, we proposed a new method which is using single channel ADC to acquire multi-channel biopotential signals modulated by square waves synchronously. In this method, a specific modulate and demodulate method has been investigated without complex signal processing schemes. For each channel, the sampling rate would not decline with the increase of the number of signal channels. More specifically, the signal-to-noise ratio of each channel is n times of the time-division method or an improvement of 3.01 ×log2n dB, where n represents the number of the signal channels. A numerical simulation shows the feasibility and validity of this method. Besides, a newly developed 8-lead ECG based on the new method has been introduced. These experiments illustrate that the method is practicable and thus is potential for low-cost medical monitors.

FDM and DMT performance comparison in high capacity point-to-point fibre links for intra/inter-datacentre connections

NASA Astrophysics Data System (ADS)

Gatto, A.; Parolari, P.; Boffi, P.

2018-05-01

Frequency division multiplexing (FDM) is attractive to achieve high capacities in multiple access networks characterized by direct modulation and direct detection. In this paper we take into account point-to-point intra- and inter-datacenter connections to understand the performance of FDM operation compared with the ones achievable with standard multiple carrier modulation approach based on discrete multitone (DMT). DMT and FDM allow to match the non-uniform and bandwidth-limited response of the system under test, associated with the employment of low-cost directly-modulated sources, such as VCSELs with high-frequency chirp, and with fibre-propagation in presence of chromatic dispersion. While for very short distances typical of intra-datacentre communications, the huge number of DMT subcarriers permits to increase the transported capacity with respect to the FDM employment, in case of few tens-km reaches typical of inter-datacentre connections, the capabilities of FDM are more evident, providing system performance similar to the case of DMT application.

DISP: Optimizations towards Scalable MPI Startup

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, Huansong; Pophale, Swaroop S; Gorentla Venkata, Manjunath

2016-01-01

Despite the popularity of MPI for high performance computing, the startup of MPI programs faces a scalability challenge as both the execution time and memory consumption increase drastically at scale. We have examined this problem using the collective modules of Cheetah and Tuned in Open MPI as representative implementations. Previous improvements for collectives have focused on algorithmic advances and hardware off-load. In this paper, we examine the startup cost of the collective module within a communicator and explore various techniques to improve its efficiency and scalability. Accordingly, we have developed a new scalable startup scheme with three internal techniques, namelymore » Delayed Initialization, Module Sharing and Prediction-based Topology Setup (DISP). Our DISP scheme greatly benefits the collective initialization of the Cheetah module. At the same time, it helps boost the performance of non-collective initialization in the Tuned module. We evaluate the performance of our implementation on Titan supercomputer at ORNL with up to 4096 processes. The results show that our delayed initialization can speed up the startup of Tuned and Cheetah by an average of 32.0% and 29.2%, respectively, our module sharing can reduce the memory consumption of Tuned and Cheetah by up to 24.1% and 83.5%, respectively, and our prediction-based topology setup can speed up the startup of Cheetah by up to 80%.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vinke, R; Peng, H; Xing, L

Purpose: In searching for a robust, efficient and cost-effective dual energy cone beam CT (DECBCT) solution for various radiation oncology applications, in particularly for improved proton dose planning/replanning accuracy and DE-CBCT guided radiation therapy, we investigate a novel energy modulation scheme using a beam modifier placed between the source and patient and optimize its geometric configuration for routine clinical use. Methods: The study was performed using a Hitachi CBCT scanner and the tube voltage was set at 125 kVp. The higher energy beam was obtained by filtering the incident utilizing a beam modulation layer (material: copper, thickness: 1.8 mm). Tomore » avoid the need for double scans (one with and one without the energy modulator), the modulation layer was configured to cover only the half of the X-ray beam so that two sets of sinograms corresponding low and high energies were collected after a single gantry rotation of 360 deg. The average high energy and low energy HU numbers (HUhigh and HUlow) were derived for pixels in a defined region-of-interest, respectively. Results: The beam modifier increased the threshold of the energy spectrum from ∼20 keV up to ∼50 keV. Two complete sets of images were obtained with good alignment between the high energy and low-energy cases without any artifact observed (Fig. 2). The HUlow/HUhigh is ∼0/0 (water), ∼394/238 (brain), ∼1283/1085 (cortical bone) and ∼3000/1800 (titanium). Conclusion: The feasibility of the proposed DECT implementation using a beam modifier has been demonstrated. Compared to the existing DECT solutions, the proposed scheme is much more cost-effective and requires minimum hardware modification. The work lays foundation for us to study the quantification of HU values to derive material density images and atomic number (and electron density) of substances.« less

Applications of 1.55 μm optically injection-locked VCSELs in wavelength division multiplexed passive optical networks

NASA Astrophysics Data System (ADS)

Wong, Elaine; Zhao, Xiaoxue; Chang-Hasnain, Connie J.; Hofmann, Werner; Amann, Marcus C.

2007-11-01

In this paper, we will discuss the utilization of optically injection-locked (OIL) 1.55 μm vertical-cavity surface-emitting lasers (VCSELs) for operation as low-cost, stable, directly modulated, and potentially uncooled transmitters, whereby the injection-locking master source is furnished by modulated downstream signals. Such a transmitter will find useful application in wavelength division multiplexed passive optical networks (WDM-PONs) which is actively being developed to meet the ever-increasing bandwidth demands of end users. Our scheme eliminates the need for external injection locking optical sources, external modulators, and wavelength stabilization circuitry. We show through experiments that the injection-locked VCSEL favors low injection powers and responds only strongly to the carrier but not the modulated data of the downstream signal. Further, we will discuss results from experimental studies performed on the dependence of OIL-VCSELs in bidirectional networks on the degree of Rayleigh backscattered signal and extinction ratio. We show that error-free upstream performance can be achieved when the upstream signal to Rayleigh backscattering ratio is greater than 13.4 dB, and with minimal dependence on the downstream extinction ratio. We will also review a fault monitoring and localization scheme based on a highly-sensitive yet low-cost monitor comprising a low output power broadband source and low bandwidth detectors. The proposed scheme benefits from the high reflectivity top distributed Bragg reflector mirror of the OIL-VCSEL, incurring only a minimal penalty on the upstream transmissions of the existing infrastructure. Such a scheme provides fault monitoring without having to further invest in the upgrade of customer premises.

A cost-effective WDM-PON architecture simultaneously supporting wired, wireless and optical VPN services

NASA Astrophysics Data System (ADS)

Wu, Yanzhi; Ye, Tong; Zhang, Liang; Hu, Xiaofeng; Li, Xinwan; Su, Yikai

2011-03-01

It is believed that next-generation passive optical networks (PONs) are required to provide flexible and various services to users in a cost-effective way. To address this issue, for the first time, this paper proposes and demonstrates a novel wavelength-division-multiplexed PON (WDM-PON) architecture to simultaneously support three types of services: 1) wireless access traffic, 2) optical virtual passive network (VPN) communications, and 3) conventional wired services. In the optical line terminal (OLT), we use two cascaded Mach-Zehnder modulators (MZMs) on each wavelength channel to generate an optical carrier, and produce the wireless and the downstream traffic using the orthogonal modulation technique. In each optical network unit (ONU), the obtained optical carrier is modulated by a single MZM to provide the VPN and upstream communications. Consequently, the light sources in the ONUs are saved and the system cost is reduced. The feasibility of our proposal is experimentally and numerically verified.

Thermal and other tests of photovoltaic modules performed in natural sunlight

NASA Technical Reports Server (NTRS)

Stultz, J. W.

1979-01-01

The nominal operating cell temperature (NOCT), an effective way to characterize the thermal performance of a photovoltaic module in natural sunlight, is developed. NOCT measurements for more than twenty different modules are presented. Changes in NOCT reflect changes in module design, residential roof mounting, and dirt accumulation. Other test results show that electrical performance is improved by cooling modules with water and by use of a phase change wax. Electrical degradation resulting from the marriage of photovoltaic and solar water heating modules is demonstrated. Cost-effectiveness of each of these techniques is evaluated.

Phase 2 of the Array Automated Assembly Task for the Low Cost Silicon Solar Array Project

NASA Technical Reports Server (NTRS)

Wihl, M.; Torro, J.; Scheinine, A.; Anderson, J.

1978-01-01

An automated process sequence, to manufacture photovoltaic modules at a capacity of approximately 500 MW per year at a cost of approximately $0.50 per peak watt is described. Verification tests were performed and are reported along with cost predictions.

Space transfer vehicle concepts and requirements study. Volume 3, book 1: Program cost estimates

NASA Technical Reports Server (NTRS)

Peffley, Al F.

1991-01-01

The Space Transfer Vehicle (STV) Concepts and Requirements Study cost estimate and program planning analysis is presented. The cost estimating technique used to support STV system, subsystem, and component cost analysis is a mixture of parametric cost estimating and selective cost analogy approaches. The parametric cost analysis is aimed at developing cost-effective aerobrake, crew module, tank module, and lander designs with the parametric cost estimates data. This is accomplished using cost as a design parameter in an iterative process with conceptual design input information. The parametric estimating approach segregates costs by major program life cycle phase (development, production, integration, and launch support). These phases are further broken out into major hardware subsystems, software functions, and tasks according to the STV preliminary program work breakdown structure (WBS). The WBS is defined to a low enough level of detail by the study team to highlight STV system cost drivers. This level of cost visibility provided the basis for cost sensitivity analysis against various design approaches aimed at achieving a cost-effective design. The cost approach, methodology, and rationale are described. A chronological record of the interim review material relating to cost analysis is included along with a brief summary of the study contract tasks accomplished during that period of review and the key conclusions or observations identified that relate to STV program cost estimates. The STV life cycle costs are estimated on the proprietary parametric cost model (PCM) with inputs organized by a project WBS. Preliminary life cycle schedules are also included.

Design of high-reliability low-cost amorphous silicon modules for high energy yield

NASA Astrophysics Data System (ADS)

Jansen, Kai W.; Varvar, Anthony; Twesme, Edward; Berens, Troy; Dhere, Neelkanth G.

2008-08-01

For PV modules to fulfill their intended purpose, they must generate sufficient economic return over their lifetime to justify their initial cost. Not only must modules be manufactured at a low cost/Wp with a high energy yield (kWh/kWp), they must also be designed to withstand the significant environmental stresses experienced throughout their 25+ year lifetime. Based on field experience, the most common factors affecting the lifetime energy yield of glass-based amorphous silicon (a-Si) modules have been identified; these include: 1) light-induced degradation; 2) moisture ingress and thin film corrosion; 3) transparent conductive oxide (TCO) delamination; and 4) glass breakage. The current approaches to mitigating the effect of these degradation mechanisms are discussed and the accelerated tests designed to simulate some of the field failures are described. In some cases, novel accelerated tests have been created to facilitate the development of improved manufacturing processes, including a unique test to screen for TCO delamination. Modules using the most reliable designs are tested in high voltage arrays at customer and internal test sites, as well as at independent laboratories. Data from tests at the Florida Solar Energy Center has shown that a-Si tandem modules can demonstrate an energy yield exceeding 1200 kWh/kWp/yr in a subtropical climate. In the same study, the test arrays demonstrated low long-term power loss over two years of data collection, after initial stabilization. The absolute power produced by the test arrays varied seasonally by approximately +/-7%, as expected.

Wafer integrated micro-scale concentrating photovoltaics

NASA Astrophysics Data System (ADS)

Gu, Tian; Li, Duanhui; Li, Lan; Jared, Bradley; Keeler, Gordon; Miller, Bill; Sweatt, William; Paap, Scott; Saavedra, Michael; Das, Ujjwal; Hegedus, Steve; Tauke-Pedretti, Anna; Hu, Juejun

2017-09-01

Recent development of a novel micro-scale PV/CPV technology is presented. The Wafer Integrated Micro-scale PV approach (WPV) seamlessly integrates multijunction micro-cells with a multi-functional silicon platform that provides optical micro-concentration, hybrid photovoltaic, and mechanical micro-assembly. The wafer-embedded micro-concentrating elements is shown to considerably improve the concentration-acceptance-angle product, potentially leading to dramatically reduced module materials and fabrication costs, sufficient angular tolerance for low-cost trackers, and an ultra-compact optical architecture, which makes the WPV module compatible with commercial flat panel infrastructures. The PV/CPV hybrid architecture further allows the collection of both direct and diffuse sunlight, thus extending the geographic and market domains for cost-effective PV system deployment. The WPV approach can potentially benefits from both the high performance of multijunction cells and the low cost of flat plate Si PV systems.

Moving Toward Quantifying Reliability - The Next Step in a Rapidly Maturing PV Industry: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah; Sample, Tony; Wohlgemuth, John

2015-12-07

Some may say that PV modules are moving toward being a simple commodity, but most major PV customers ask: 'How can I minimize chances of a module recall?' Or, 'How can I quantify the added value of a 'premium' module?' Or, 'How can I assess the value of an old PV system that I'm thinking of purchasing?' These are all questions that PVQAT (the International PV Quality Assurance Task Force) and partner organizations are working to answer. Defining standard methods for ensuring minimal acceptable quality of PV modules, differentiating modules that provide added value in the toughest of environments, andmore » creating a process (e.g. through IECRE [1]) that can follow a PV system from design through installation and operation are tough tasks, but having standard approaches for these will increase confidence, reduce costs, and be a critical foundation of a mature PV industry. This paper summarizes current needs for new tests, some challenges for defining those tests, and some of the key efforts toward development of international standards, emphasizing that meaningful quantification of reliability (as in defining a service life prediction) must be done in the context of a specific product with design parameters defined through a quality management system.« less

Advanced development of a programmable power processor

NASA Technical Reports Server (NTRS)

Lukens, F. E.; Lanier, J. R., Jr.; Kapustka, R. E.; Graves, J.

1980-01-01

The need for the development of a multipurpose flexible programmable power processor (PPP) has increased significantly in recent years to reduce ever rising development costs. One of the program requirements the PPP specification will cover is the 25 kW power module power conversion needs. The 25 kW power module could support the Space Shuttle program during the 1980s and 1990s and could be the stepping stone to future large space programs. Trades that led to selection of a microprocessor controlled power processor are briefly discussed. Emphasis is given to the power processing equipment that uses a microprocessor to provide versatility that allows multiple use and to provide for future growth by reprogramming output voltage to a higher level (to 120 V from 30 V). Component selection and design considerations are also discussed.

Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 6: IPAD system development and operation

NASA Technical Reports Server (NTRS)

Redhed, D. D.; Tripp, L. L.; Kawaguchi, A. S.; Miller, R. E., Jr.

1973-01-01

The strategy of the IPAD implementation plan presented, proposes a three phase development of the IPAD system and technical modules, and the transfer of this capability from the development environment to the aerospace vehicle design environment. The system and technical module capabilities for each phase of development are described. The system and technical module programming languages are recommended as well as the initial host computer system hardware and operating system. The cost of developing the IPAD technology is estimated. A schedule displaying the flowtime required for each development task is given. A PERT chart gives the developmental relationships of each of the tasks and an estimate of the operational cost of the IPAD system is offered.

Innovative Ballasted Flat Roof Solar PV Racking System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peek, Richard T.

2014-12-15

The objective of this project was to reduce the cost of racking for PV solar on flat commercial rooftops. Cost reductions would come from both labor savings and material savings related to the installation process. The rack would need to accommodate the majority of modules available on the market. Cascade Engineering has a long history of converting traditional metal type applications over to plastic. Injection molding of plastics have numerous advantages including selection of resin for the application, placing the material exactly where it is needed, designing in features that will speed up the installation process, and weight reduction ofmore » the array. A plastic rack would need to meet the requirements of UL2703, Mounting systems, mounting devices, clamping/retention devices, and ground lugs for use with flat-plate photovoltaic modules and panels. Comparing original data to the end of project racking design, racking material costs were reduced 50% and labor costs reduced 64%. The racking product accommodates all 60 and 72 cell panels on the market, meets UL2703 requirements, contributes only 1.3 pounds per square foot of weight to the array, requires little ballast to secure the array, automatically grounds the module when the module is secured, stacks/nests well for shipping/fewer lifts to the roof, provides integrated wire routing, allows water to drain on the roof, and accommodates various seismic roof connections. Project goals were achieved as noted in the original funding application.« less

A Novel c-VEP BCI Paradigm for Increasing the Number of Stimulus Targets Based on Grouping Modulation With Different Codes.

PubMed

Wei, Qingguo; Liu, Yonghui; Gao, Xiaorong; Wang, Yijun; Yang, Chen; Lu, Zongwu; Gong, Huayuan

2018-06-01

In an existing brain-computer interface (BCI) based on code modulated visual evoked potentials (c-VEP), a method with which to increase the number of targets without increasing code length has not yet been established. In this paper, a novel c-VEP BCI paradigm, namely, grouping modulation with different codes that have good autocorrelation and crosscorrelation properties, is presented to increase the number of targets and information transfer rate (ITR). All stimulus targets are divided into several groups and each group of targets are modulated by a distinct pseudorandom binary code and its circularly shifting codes. Canonical correlation analysis is applied to each group for yielding a spatial filter and templates for all targets in a group are constructed based on spatially filtered signals. Template matching is applied to each group and the attended target is recognized by finding the maximal correlation coefficients of all groups. Based on the paradigm, a BCI with a total of 48 targets divided into three groups was implemented; 12 and 10 subjects participated in an off-line and a simulated online experiments, respectively. Data analysis of the offline experiment showed that the paradigm can massively increase the number of targets from 16 to 48 at the cost of slight compromise in accuracy (95.49% vs. 92.85%). Results of the simulated online experiment suggested that although the averaged accuracy across subjects of all three groups of targets was lower than that of a single group of targets (91.67% vs. 94.9%), the average ITR of the former was substantially higher than that of the later (181 bits/min vs. 135.6 bit/min) due to the large increase of the number of targets. The proposed paradigm significantly improves the performance of the c-VEP BCI, and thereby facilitates its practical applications such as high-speed spelling.

Environmental testing of block 2 solar cell modules

NASA Technical Reports Server (NTRS)

Griffith, J. S.

1979-01-01

The testing procedures and results of samples of the LSA Project Block 2 procurement of silicon solar cell modules are described. Block 2 was the second large scale procurement of silicon solar cell modules made by the JPL Low-cost Solar Array Project with deliveries in 1977 and early 1978. The results showed that the Block 2 modules were greatly improved over Block 1 modules. In several cases it was shown that design improvements were needed to reduce environmental test degradation. These improvements were incorporated during this production run.

Advanced modulation technology development for earth station demodulator applications

NASA Technical Reports Server (NTRS)

Davis, R. C.; Wernlund, J. V.; Gann, J. A.; Roesch, J. F.; Wright, T.; Crowley, R. D.

1989-01-01

The purpose of this contract was to develop a high rate (200 Mbps), bandwidth efficient, modulation format using low cost hardware, in 1990's technology. The modulation format chosen is 16-ary continuous phase frequency shift keying (CPFSK). The implementation of the modulation format uses a unique combination of a limiter/discriminator followed by an accumulator to determine transmitted phase. An important feature of the modulation scheme is the way coding is applied to efficiently gain back the performance lost by the close spacing of the phase points.

DOE Office of Scientific and Technical Information (OSTI.GOV)

STADLER, MICHAEL; MASHAYEKH, SALMAN; DEFOREST, NICHOLAS

The ODC Microgrid Controller is an optimization-based model predicative microgrid controller (MPMC) to minimize operation cost (and/or CO2 emissions) in a microgrid in the grid-connected mode. It is composed of several modules, including a) forecasting, b) optimization, c) data exchange and d) power balancing modules. In the presence of a multi-layered control system architecture, these modules will reside in the supervisory control layer.

The Capital Intensity of Photovoltaics Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basore, Paul

2015-10-19

Factory capital expenditure (capex) for photovoltaic (PV) module manufacturing strongly influences the per-unit cost of a c-Si module. This provides a significant opportunity to address the U.S. DOE SunShot module price target through capex innovation. Innovation options to reduce the capex of PV manufacturing include incremental and disruptive process innovation with c-Si, platform innovations, and financial approaches. and financial approaches.

Nighttime Supplemental LED Inter-lighting Improves Growth and Yield of Single-Truss Tomatoes by Enhancing Photosynthesis in Both Winter and Summer.

PubMed

Tewolde, Fasil T; Lu, Na; Shiina, Kouta; Maruo, Toru; Takagaki, Michiko; Kozai, Toyoki; Yamori, Wataru

2016-01-01

Greenhouses with sophisticated environmental control systems, or so-called plant factories with solar light, enable growers to achieve high yields of produce with desirable qualities. In a greenhouse crop with high planting density, low photosynthetic photon flux density (PPFD) at the lower leaves tends to limit plant growth, especially in the winter when the solar altitude and PPFD at the canopy are low and day length is shorter than in summer. Therefore, providing supplemental lighting to the lower canopy can increase year-round productivity. However, supplemental lighting can be expensive. In some places, the cost of electricity is lower at night, but the effect of using supplemental light at night has not yet been examined. In this study, we examined the effects of supplemental LED inter-lighting (LED inter-lighting hereafter) during the daytime or nighttime on photosynthesis, growth, and yield of single-truss tomato plants both in winter and summer. We used LED inter-lighting modules with combined red and blue light to illuminate lower leaves right after the first anthesis. The PPFD of this light was 165 μmol m(-2) s(-1) measured at 10 cm from the LED module. LED inter-lighting was provided from 4:00 am to 4:00 pm for the daytime treatments and from 10:00 pm to 10:00 am for the nighttime treatments. Plants exposed only to solar light were used as controls. Daytime LED inter-lighting increased the photosynthetic capacity of middle and lower canopy leaves, which significantly increased yield by 27% in winter; however, photosynthetic capacity and yield were not significantly increased during summer. Nighttime LED inter-lighting increased photosynthetic capacity in both winter and summer, and yield increased by 24% in winter and 12% in summer. In addition, nighttime LED inter-lighting in winter significantly increased the total soluble solids and ascorbic acid content of the tomato fruits, by 20 and 25%, respectively. Use of nighttime LED inter-lighting was also more cost-effective than daytime inter-lighting. Thus, nighttime LED inter-lighting can effectively improve tomato plant growth and yield with lower energy cost compared with daytime both in summer and winter.

Nighttime Supplemental LED Inter-lighting Improves Growth and Yield of Single-Truss Tomatoes by Enhancing Photosynthesis in Both Winter and Summer

PubMed Central

Tewolde, Fasil T.; Lu, Na; Shiina, Kouta; Maruo, Toru; Takagaki, Michiko; Kozai, Toyoki; Yamori, Wataru

2016-01-01

Greenhouses with sophisticated environmental control systems, or so-called plant factories with solar light, enable growers to achieve high yields of produce with desirable qualities. In a greenhouse crop with high planting density, low photosynthetic photon flux density (PPFD) at the lower leaves tends to limit plant growth, especially in the winter when the solar altitude and PPFD at the canopy are low and day length is shorter than in summer. Therefore, providing supplemental lighting to the lower canopy can increase year-round productivity. However, supplemental lighting can be expensive. In some places, the cost of electricity is lower at night, but the effect of using supplemental light at night has not yet been examined. In this study, we examined the effects of supplemental LED inter-lighting (LED inter-lighting hereafter) during the daytime or nighttime on photosynthesis, growth, and yield of single-truss tomato plants both in winter and summer. We used LED inter-lighting modules with combined red and blue light to illuminate lower leaves right after the first anthesis. The PPFD of this light was 165 μmol m-2 s-1 measured at 10 cm from the LED module. LED inter-lighting was provided from 4:00 am to 4:00 pm for the daytime treatments and from 10:00 pm to 10:00 am for the nighttime treatments. Plants exposed only to solar light were used as controls. Daytime LED inter-lighting increased the photosynthetic capacity of middle and lower canopy leaves, which significantly increased yield by 27% in winter; however, photosynthetic capacity and yield were not significantly increased during summer. Nighttime LED inter-lighting increased photosynthetic capacity in both winter and summer, and yield increased by 24% in winter and 12% in summer. In addition, nighttime LED inter-lighting in winter significantly increased the total soluble solids and ascorbic acid content of the tomato fruits, by 20 and 25%, respectively. Use of nighttime LED inter-lighting was also more cost-effective than daytime inter-lighting. Thus, nighttime LED inter-lighting can effectively improve tomato plant growth and yield with lower energy cost compared with daytime both in summer and winter. PMID:27092163

Evolution of a modular software network

PubMed Central

Fortuna, Miguel A.; Bonachela, Juan A.; Levin, Simon A.

2011-01-01

“Evolution behaves like a tinkerer” (François Jacob, Science, 1977). Software systems provide a singular opportunity to understand biological processes using concepts from network theory. The Debian GNU/Linux operating system allows us to explore the evolution of a complex network in a unique way. The modular design detected during its growth is based on the reuse of existing code in order to minimize costs during programming. The increase of modularity experienced by the system over time has not counterbalanced the increase in incompatibilities between software packages within modules. This negative effect is far from being a failure of design. A random process of package installation shows that the higher the modularity, the larger the fraction of packages working properly in a local computer. The decrease in the relative number of conflicts between packages from different modules avoids a failure in the functionality of one package spreading throughout the entire system. Some potential analogies with the evolutionary and ecological processes determining the structure of ecological networks of interacting species are discussed. PMID:22106260

GATE simulation of a new design of pinhole SPECT system for small animal brain imaging

NASA Astrophysics Data System (ADS)

Uzun Ozsahin, D.; Bläckberg, L.; El Fakhri, G.; Sabet, H.

2017-01-01

Small animal SPECT imaging has gained an increased interest over the past decade since it is an excellent tool for developing new drugs and tracers. Therefore, there is a huge effort on the development of cost-effective SPECT detectors with high capabilities. The aim of this study is to simulate the performance characteristics of new designs for a cost effective, stationary SPECT system dedicated to small animal imaging with a focus on mice brain. The conceptual design of this SPECT system platform, Stationary Small Animal SSA-SPECT, is to use many pixelated CsI:TI detector modules with 0.4 mm × 0.4 mm pixels in order to achieve excellent intrinsic detector resolution where each module is backed by a single pinhole collimator with 0.3 mm hole diameter. In this work, we present the simulation results of four variations of the SSA-SPECT platform where the number of detector modules and FOV size is varied while keeping the detector size and collimator hole size constant. Using the NEMA NU-4 protocol, we performed spatial resolution, sensitivity, image quality simulations followed by a Derenzo-like phantom evaluation. The results suggest that all four SSA-SPECT systems can provide better than 0.063% system sensitivity and < 1.5 mm FWHM spatial resolution without resolution recovery or other correction techniques. Specifically, SSA-SPECT-1 showed a system sensitivity of 0.09% in combination with 1.1 mm FWHM spatial resolution.

Symposium on the Interface: Computing Science and Statistics (20th). Theme: Computationally Intensive Methods in Statistics Held in Reston, Virginia on April 20-23, 1988

DTIC Science & Technology

1988-08-20

34 William A. Link, Patuxent Wildlife Research Center "Increasing reliability of multiversion fault-tolerant software design by modulation," Junryo 3... Multiversion lault-Tolerant Software Design by Modularization Junryo Miyashita Department of Computer Science California state University at san Bernardino Fault...They shall beE refered to as " multiversion fault-tolerant software design". Onel problem of developing multi-versions of a program is the high cost

Lock and Dam Number 8 Hydropower Study; Mississippi River Near LaCrosse, Wisconsin. Supplement.

DTIC Science & Technology

1985-01-01

unit used in scheme 3 is a standardized module consisting of an axial flow turbine , a speed increasing gear set, and a generator combined in a short...the flow and generating head ranges associated with specific turbine generator sizes, the program produces annual and monthly flow -duration curves and...open flume turbine passing a rated flow of 14O0 eta at a rated head of 9.75 feat. Cost estimates were made for two and four unit plants having

Poka Yoke system based on image analysis and object recognition

NASA Astrophysics Data System (ADS)

Belu, N.; Ionescu, L. M.; Misztal, A.; Mazăre, A.

2015-11-01

Poka Yoke is a method of quality management which is related to prevent faults from arising during production processes. It deals with “fail-sating” or “mistake-proofing”. The Poka-yoke concept was generated and developed by Shigeo Shingo for the Toyota Production System. Poka Yoke is used in many fields, especially in monitoring production processes. In many cases, identifying faults in a production process involves a higher cost than necessary cost of disposal. Usually, poke yoke solutions are based on multiple sensors that identify some nonconformities. This means the presence of different equipment (mechanical, electronic) on production line. As a consequence, coupled with the fact that the method itself is an invasive, affecting the production process, would increase its price diagnostics. The bulky machines are the means by which a Poka Yoke system can be implemented become more sophisticated. In this paper we propose a solution for the Poka Yoke system based on image analysis and identification of faults. The solution consists of a module for image acquisition, mid-level processing and an object recognition module using associative memory (Hopfield network type). All are integrated into an embedded system with AD (Analog to Digital) converter and Zync 7000 (22 nm technology).

Radio over fiber transceiver employing phase modulation of an optical broadband source.

PubMed

Grassi, Fulvio; Mora, José; Ortega, Beatriz; Capmany, José

2010-10-11

This paper proposes a low-cost RoF transceiver for multichannel SCM/WDM signal distribution suitable for future broadband access networks. The transceiver is based on the phase modulation of an optical broadband source centered at third transmission window. Prior to phase modulation the optical broadband source output signal is launched into a Mach-Zehnder interferometer structure, as key device enabling radio signals propagation over the optical link. Furthermore, an optical CWDM is employed to create a multichannel scenario by performing the spectral slicing of the modulated optical signal into a number of channels each one conveying the information from the central office to different base stations. The operation range is up to 20 GHz with a modulation bandwidth around of 500 MHz. Experimental results of the transmission of SCM QPSK and 64-QAM data through 20 Km of SMF exhibit good EVM results in the operative range determined by the phase-to-intensity conversion process. The proposed approach shows a great suitability for WDM networks based on RoF signal transport and also represents a cost-effective solution for passive optical networks.

Teaching home safety and survival skills to latch-key children: a comparison of two manuals and methods.

PubMed Central

Peterson, L

1984-01-01

I evaluated the influence of two training manuals on latch-key children's acquisition of home safety and survival skills. The widely used, discussion-oriented "Prepared for Today" manual was compared with a behaviorally oriented "Safe at Home" manual. Data were scored by response criteria developed by experts and by parents' and experts' ratings of children's spontaneous answers. With both methods of scoring, three behaviorally trained children demonstrated clear and abrupt increases in skill following training in each of seven trained modules, and these increases largely persisted in real world generalization probes and at 5-month follow-up. Smaller and less stable increases in skill were found in the three discussion-trained children across the seven modules; lower skill levels were also seen in real world generalization probes and at follow-up. Neither group of children demonstrated skill increases in home safety areas that were not explicitly trained. Both training methods produced small decreases in children's self-report of general anxiety and anxiety concerning home safety. Results are discussed in terms of their implications for cost-effective training of latch-key children. PMID:6511698

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The Performance Prototype Trough (PPT) Concentrating Collector consists of four 80-foot modules in a 320-foot row. The collector was analyzed, including cost estimates and manufacturing processes to produce collectors in volumes from 100 to 100,000 modules per year. The four different reflector concepts considered were the sandwich reflector structure, sheet metal reflector structure, molded reflector structure, and glass laminate structure. The sheet metal and glass laminate structures are emphasized with their related structure concepts. A preliminary manufacturing plan is offered that includes: documentation of the manufacturing process with production flow diagrams; labor and material costs at various production levels; machinerymore » and equipment requirements including preliminary design specifications; and capital investment costs for a new plant. Of five reflector designs considered, the two judged best and considered at length are thin annealed glass and steel laminate on steel frame panel and thermally sagged glass. Also discussed are market considerations, costing and selling price estimates, design cost analysis and make/buy analysis. (LEW)« less

Development and manufacture of reactive-transfer-printed CIGS photovoltaic modules

NASA Astrophysics Data System (ADS)

Eldada, Louay; Sang, Baosheng; Lu, Dingyuan; Stanbery, Billy J.

2010-09-01

In recent years, thin-film photovoltaic (PV) companies started realizing their low manufacturing cost potential, and grabbing an increasingly larger market share from multicrystalline silicon companies. Copper Indium Gallium Selenide (CIGS) is the most promising thin-film PV material, having demonstrated the highest energy conversion efficiency in both cells and modules. However, most CIGS manufacturers still face the challenge of delivering a reliable and rapid manufacturing process that can scale effectively and deliver on the promise of this material system. HelioVolt has developed a reactive transfer process for CIGS absorber formation that has the benefits of good compositional control, high-quality CIGS grains, and a fast reaction. The reactive transfer process is a two stage CIGS fabrication method. Precursor films are deposited onto substrates and reusable print plates in the first stage, while in the second stage, the CIGS layer is formed by rapid heating with Se confinement. High quality CIGS films with large grains were produced on a full-scale manufacturing line, and resulted in high-efficiency large-form-factor modules. With 14% cell efficiency and 12% module efficiency, HelioVolt started to commercialize the process on its first production line with 20 MW nameplate capacity.

A novel nonlinear adaptive filter using a pipelined second-order Volterra recurrent neural network.

PubMed

Zhao, Haiquan; Zhang, Jiashu

2009-12-01

To enhance the performance and overcome the heavy computational complexity of recurrent neural networks (RNN), a novel nonlinear adaptive filter based on a pipelined second-order Volterra recurrent neural network (PSOVRNN) is proposed in this paper. A modified real-time recurrent learning (RTRL) algorithm of the proposed filter is derived in much more detail. The PSOVRNN comprises of a number of simple small-scale second-order Volterra recurrent neural network (SOVRNN) modules. In contrast to the standard RNN, these modules of a PSOVRNN can be performed simultaneously in a pipelined parallelism fashion, which can lead to a significant improvement in its total computational efficiency. Moreover, since each module of the PSOVRNN is a SOVRNN in which nonlinearity is introduced by the recursive second-order Volterra (RSOV) expansion, its performance can be further improved. Computer simulations have demonstrated that the PSOVRNN performs better than the pipelined recurrent neural network (PRNN) and RNN for nonlinear colored signals prediction and nonlinear channel equalization. However, the superiority of the PSOVRNN over the PRNN is at the cost of increasing computational complexity due to the introduced nonlinear expansion of each module.

NREL to Lead New Consortium to Improve Reliability and Performance of Solar

Science.gov Websites

for photovoltaics (PV) and lower the cost of electricity generated by solar power. The Durable Module the cost of electricity from photovoltaics." The Energy Department's Office of Energy Efficiency , DuraMat will address the substantial opportunities that exist for durable, high-performance, low-cost

A sensitivity analysis of central flat-plate photovoltaic systems and implications for national photovoltaics program planning

NASA Technical Reports Server (NTRS)

Crosetti, M. R.

1985-01-01

The sensitivity of the National Photovoltaic Research Program goals to changes in individual photovoltaic system parameters is explored. Using the relationship between lifetime cost and system performance parameters, tests were made to see how overall photovoltaic system energy costs are affected by changes in the goals set for module cost and efficiency, system component costs and efficiencies, operation and maintenance costs, and indirect costs. The results are presented in tables and figures for easy reference.

Silicon solar photovoltaic power stations

NASA Technical Reports Server (NTRS)

Chowaniec, C. R.; Ferber, R. R.; Pittman, P. F.; Marshall, B. W.

1977-01-01

Modular design of components and arrays, cost estimates for modules and support structures, and cost/performance analysis of a central solar photovoltaic power plant are discussed. Costs of collector/reflector arrays are judged the dominant element in the total capital investment. High-concentration solar tracking arrays are recommended as the most economic means for producing solar photovoltaic energy when solar cells costs are high ($500 per kW generated). Capital costs for power conditioning subsystem components are itemized and system busbar energy costs are discussed at length.

Manufacturing Methods and Technology Program for Low Cost Hybrid Silicon Photodetector Modules

DTIC Science & Technology

1979-12-30

RESEARCH LN EVEMN TECHNICAL REPORT 4 CORADOOM- 77- C -0489-F I CMANUFACTURING METHODS AND TECHNOLOGY PROGRAM FOR LOW COST HYBRID SILICON PHOTODETECTORS...rINAL REPORT OR US ARMY CONTRACT NO, DAAD07-77- C -0489 TITLED 11MM&TMud SURE FOR COS HYBRID SILICON PHOTODRTECTOR MODULS", DATED 79/12/30 Gentlemen...when it is no longer needed. Do not return it to the originator. D.-stributi-on! Availability COcas- :Dist c specia S I ’ Cb.A *"itI. -P0 ~~J~,+~1

Integrated residential photovoltaic array development

NASA Technical Reports Server (NTRS)

Shepard, N. F., Jr.

1981-01-01

The design details of an optimized integrated residential photovoltaic module/array are presented. This selected design features a waterproofing and mounting scheme which was devised to simplify the installation procedures by the avoidance of complex gasketed or caulked joints, while still maintaining a high confidence that the watertight integrity of the integral roofing surface will be achieved for the design lifetime of the system. The production and installation costs for the selected module/array design are reported for a range of annual production rates as a function of the cost of solar cells.

Availability and Diversity of Training Programs for Responders to International Disasters and Complex Humanitarian Emergencies

PubMed Central

Jacquet, Gabrielle A.; Obi, Chioma C.; Chang, Mary P.; Bayram, Jamil D.

2014-01-01

Introduction: Volunteers and members of relief organizations increasingly seek formal training prior to international field deployment. This paper identifies training programs for personnel responding to international disasters and complex humanitarian emergencies, and provides concise information – if available- regarding the founding organization, year established, location, cost, duration of training, participants targeted, and the content of each program. Methods: An environmental scan was conducted through a combination of a peer-reviewed literature search and an open Internet search for the training programs. Literature search engines included EMBASE, Cochrane, Scopus, PubMed, Web of Science databases using the search terms “international,” “disaster,” “complex humanitarian emergencies,” “training,” and “humanitarian response”. Both searches were conducted between January 2, 2013 and September 12, 2013. Results: 14 peer-reviewed articles mentioned or described eight training programs, while open Internet search revealed 13 additional programs. In total, twenty-one training programs were identified as currently available for responders to international disasters and CHE. Each of the programs identified has different goals and objectives, duration, expenses, targeted trainees and modules. Each of the programs identified has different goals and objectives, duration, expenses, targeted trainees and modules. Seven programs (33%) are free of charge and four programs (19%) focus on the mental aspects of disasters. The mean duration for each training program is 5 to 7 days. Fourteen of the trainings are conducted in multiple locations (66%), two in Cuba (9%) and two in Australia (9%). The cost-reported in US dollars- ranges from $100 to $2,400 with a mean cost of $480 and a median cost of $135. Most of the programs are open to the public, but some are only available by invitation only, such as the International Mobilization Preparation for Action (IMPACT) and the United Nations Humanitarian Civil-Military Coordination (UN-CMCoord) Field Course. Conclusions: A variety of training programs are available for responders to disasters and complex humanitarian emergencies. These programs vary in their objectives, audiences, modules, geographical locations, eligibility and financial cost. This paper presents an overview of available programs and serves as a resource for potential responders interested in capacity-building training prior to deployment. PMID:24987573

Cost-efficiency trade-off and the design of thermoelectric power generators.

PubMed

Yazawa, Kazuaki; Shakouri, Ali

2011-09-01

The energy conversion efficiency of today's thermoelectric generators is significantly lower than that of conventional mechanical engines. Almost all of the existing research is focused on materials to improve the conversion efficiency. Here we propose a general framework to study the cost-efficiency trade-off for thermoelectric power generation. A key factor is the optimization of thermoelectric modules together with their heat source and heat sinks. Full electrical and thermal co-optimization yield a simple analytical expression for optimum design. Based on this model, power output per unit mass can be maximized. We show that the fractional area coverage of thermoelectric elements in a module could play a significant role in reducing the cost of power generation systems.

Computer program to assess impact of fatigue and fracture criteria on weight and cost of transport aircraft

NASA Technical Reports Server (NTRS)

Tanner, C. J.; Kruse, G. S.; Oman, B. H.

1975-01-01

A preliminary design analysis tool for rapidly performing trade-off studies involving fatigue, fracture, static strength, weight, and cost is presented. Analysis subprograms were developed for fatigue life, crack growth life, and residual strength; and linked to a structural synthesis module which in turn was integrated into a computer program. The part definition module of a cost and weight analysis program was expanded to be compatible with the upgraded structural synthesis capability. The resultant vehicle design and evaluation program is named VDEP-2. It is an accurate and useful tool for estimating purposes at the preliminary design stage of airframe development. A sample case along with an explanation of program applications and input preparation is presented.

Modular space station

NASA Technical Reports Server (NTRS)

1972-01-01

The modular space station comprising small, shuttle-launched modules, and characterized by low initial cost and incremental manning, is described. The initial space station is designed to be delivered into orbit by three space shuttles and assembled in space. The three sections are the power/subsystems module, the crew/operations module, and the general purpose laboratory module. It provides for a crew of six. Subsequently duplicate/crew/operations and power/subsystems modules will be mated to the original modules, and provide for an additional six crewmen. A total of 17 research and applications modules is planned, three of which will be free-flying modules. Details are given on the program plan, modular characteristics, logistics, experiment support capability and requirements, operations analysis, design support analyses, and shuttle interfaces.

Status and Trend of Automotive Power Packaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liang, Zhenxian

2012-01-01

Comprehensive requirements in aspects of cost, reliability, efficiency, form factor, weight, and volume for power electronics modules in modern electric drive vehicles have driven the development of automotive power packaging technology intensively. Innovation in materials, interconnections, and processing techniques is leading to enormous improvements in power modules. In this paper, the technical development of and trends in power module packaging are evaluated by examining technical details with examples of industrial products. The issues and development directions for future automotive power module packaging are also discussed.

Criteria for software modularization

NASA Technical Reports Server (NTRS)

Card, David N.; Page, Gerald T.; Mcgarry, Frank E.

1985-01-01

A central issue in programming practice involves determining the appropriate size and information content of a software module. This study attempted to determine the effectiveness of two widely used criteria for software modularization, strength and size, in reducing fault rate and development cost. Data from 453 FORTRAN modules developed by professional programmers were analyzed. The results indicated that module strength is a good criterion with respect to fault rate, whereas arbitrary module size limitations inhibit programmer productivity. This analysis is a first step toward defining empirically based standards for software modularization.

Phase-Change Heat-Storage Module

NASA Technical Reports Server (NTRS)

Mulligan, James C.

1989-01-01

Heat-storage module accommodates momentary heating or cooling overload in pumped-liquid heat-transfer system. Large heat-storage capacity of module provided by heat of fusion of material that freezes at or near temperature desired to maintain object to be heated or cooled. Module involves relatively small penalties in weight, cost, and size and more than compensates by enabling design of rest of system to handle only average load. Latent heat of fusion of phase-change material provides large heat-storage capacity in small volume.

Investigation of test methods, material properties, and processes for solar cell encapsulants. Fourteenth quarterly progress report, August 12, 1978-November 12, 1979. [EVA, EPDM, aliphatic urethane, PVC plastisol, and butyl acrylate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Willis, P. B.; Baum, B.; Schnitzer, H. S.

1979-12-01

Springborn Laboratories is engaged in a study of evaluating potentially useful encapsulating materials for Task 3 of the Low-Cost Silicon Solar Array project (LSA) funded by DOE. The goal of this program is to identify, evaluate, and recommend encapsulant materials and processes for the production of cost-effective, long-life solar cell modules. This report presents the results of a cost analysis of candidate potting compounds for long life solar module encapsulation. Additionally, the two major encapsulation processes, sheet lamination and liquid casting, are costed on the basis of a large scale production facility. Potting compounds studied include EVA, sheet, clear; EVA,more » sheet, pigmented; EPDM, sheet, clear; Aliphatic urethane, syrup; PVC Plastisol; Butyl acrylate, syrup; and Butyl acrylate, sheet.« less

Residential photovoltaic module and array requirements study, appendices

NASA Technical Reports Server (NTRS)

Nearhoof, S. L.; Oster, J. R.

1979-01-01

Regional building code variations, federal and city codes, and the national electric code are reviewed for their possible effects on the design of photovoltaic modules. Problems that photovoltaic arrays may impose on the insurability of residences are also discussed. Mounting configurations are developed for the modules, and grounding, wiring, terminal, and voltage requirements are established. Installation and materials costs are presented along with performance criteria.

Bioresearch module design definition and space shuttle vehicle integration. Volume 3: Management and funding plan

NASA Technical Reports Server (NTRS)

1971-01-01

A description is given of the proposed project organization, documentation and reports, project planning, direction and control, related experience and facilities, and cost estimate data and options for the implementation of the bioresearch module development program.

Impacts of Low Salinity on Growth and Calcification in Baltic Sea Mytilus edulis x trossulus

NASA Astrophysics Data System (ADS)

Sanders, T.; Melzner, F.

2016-02-01

The Baltic Sea is characterized by a steep salinity gradient (25 psu - <5 psu) which is predicted to increase in the future due to increased precipitation. This provides an excellent biological system to study the effects of salinity and inorganic carbon supply on animal physiology. Mytilus edulis x trossulus is adapted to the low saline Baltic Sea, at the cost of slow body growth and reduced shell thickness. The explanation for the small size of Baltic mytilids has been attributed to tradeoffs in energy partitioning due to high energetic costs associated with osmoregulation. However, salinity may effect calcification mechanisms and reduce calcification and thus, body size and growth. To understand the mechanistic effects salinity has on calcification, energy budgets were quantified in larvae, juveniles and adults from 3 populations of Baltic Sea Mytilus spp. at different salinities (6, 11 and 16 psu). Net CaCO3 production at varying salinities and bicarbonate concentrations was also measured. Larvae from low salinity adapted populations (6 psu) had a 3-fold higher respiration rate compared to higher salinity populations. This was also accompanied by a delay of 48 hours in early shell formation. Reductions in growth and increases in metabolism were largest between 11 psu and 6 psu indicating that the predicted desalination of the Baltic will go along with huge energetic costs for mussel populations, potentially leading to loss of reefs in the Eastern Baltic. To investigate the mechanisms behind increased metabolic cost and decreased allocation to growth, energy budgets are presently being constrained in our three populations using modulations in food supply and temperature.

Persistency and flexibility of complex brain networks underlie dual-task interference.

PubMed

Alavash, Mohsen; Hilgetag, Claus C; Thiel, Christiane M; Gießing, Carsten

2015-09-01

Previous studies on multitasking suggest that performance decline during concurrent task processing arises from interfering brain modules. Here, we used graph-theoretical network analysis to define functional brain modules and relate the modular organization of complex brain networks to behavioral dual-task costs. Based on resting-state and task fMRI we explored two organizational aspects potentially associated with behavioral interference when human subjects performed a visuospatial and speech task simultaneously: the topological overlap between persistent single-task modules, and the flexibility of single-task modules in adaptation to the dual-task condition. Participants showed a significant decline in visuospatial accuracy in the dual-task compared with single visuospatial task. Global analysis of topological similarity between modules revealed that the overlap between single-task modules significantly correlated with the decline in visuospatial accuracy. Subjects with larger overlap between single-task modules showed higher behavioral interference. Furthermore, lower flexible reconfiguration of single-task modules in adaptation to the dual-task condition significantly correlated with larger decline in visuospatial accuracy. Subjects with lower modular flexibility showed higher behavioral interference. At the regional level, higher overlap between single-task modules and less modular flexibility in the somatomotor cortex positively correlated with the decline in visuospatial accuracy. Additionally, higher modular flexibility in cingulate and frontal control areas and lower flexibility in right-lateralized nodes comprising the middle occipital and superior temporal gyri supported dual-tasking. Our results suggest that persistency and flexibility of brain modules are important determinants of dual-task costs. We conclude that efficient dual-tasking benefits from a specific balance between flexibility and rigidity of functional brain modules. © 2015 Wiley Periodicals, Inc.

Grain-size considerations for optoelectronic multistage interconnection networks.

PubMed

Krishnamoorthy, A V; Marchand, P J; Kiamilev, F E; Esener, S C

1992-09-10

This paper investigates, at the system level, the performance-cost trade-off between optical and electronic interconnects in an optoelectronic interconnection network. The specific system considered is a packet-switched, free-space optoelectronic shuffle-exchange multistage interconnection network (MIN). System bandwidth is used as the performance measure, while system area, system power, and system volume constitute the cost measures. A detailed design and analysis of a two-dimensional (2-D) optoelectronic shuffle-exchange routing network with variable grain size K is presented. The architecture permits the conventional 2 x 2 switches or grains to be generalized to larger K x K grain sizes by replacing optical interconnects with electronic wires without affecting the functionality of the system. Thus the system consists of log(k) N optoelectronic stages interconnected with free-space K-shuffles. When K = N, the MIN consists of a single electronic stage with optical input-output. The system design use an effi ient 2-D VLSI layout and a single diffractive optical element between stages to provide the 2-D K-shuffle interconnection. Results indicate that there is an optimum range of grain sizes that provides the best performance per cost. For the specific VLSI/GaAs multiple quantum well technology and system architecture considered, grain sizes larger than 256 x 256 result in a reduced performance, while grain sizes smaller than 16 x 16 have a high cost. For a network with 4096 channels, the useful range of grain sizes corresponds to approximately 250-400 electronic transistors per optical input-output channel. The effect of varying certain technology parameters such as the number of hologram phase levels, the modulator driving voltage, the minimum detectable power, and VLSI minimum feature size on the optimum grain-size system is studied. For instance, results show that using four phase levels for the interconnection hologram is a good compromise for the cost functions mentioned above. As VLSI minimum feature sizes decrease, the optimum grain size increases, whereas, if optical interconnect performance in terms of the detector power or modulator driving voltage requirements improves, the optimum grain size may be reduced. Finally, several architectural modifications to the system, such as K x K contention-free switches and sorting networks, are investigated and optimized for grain size. Results indicate that system bandwidth can be increased, but at the price of reduced performance/cost. The optoelectronic MIN architectures considered thus provide a broad range of performance/cost alternatives and offer a superior performance over purely electronic MIN's.

30% CPV Module Milestone

NASA Astrophysics Data System (ADS)

Gordon, Robert; Kinsey, Geoff; Nayaak, Adi; Garboushian, Vahan

2010-10-01

Concentrating Photovoltaics has held out the promise of low cost solar electricity for now several decades. Steady progress towards this goal in the 80's and 90's gradually produced more efficient and reliable systems. System efficiency is regarded as the largest factor in lowering the electricity cost and the relatively recent advent of the terrestrial multi-junction solar cell has pressed this race forward dramatically. CPV systems are now exhibiting impressive AC field efficiencies of 25% and more, approximately twice that of the best flat plate systems available today. Amonix inc. has just tested their latest generation multi-junction module design, achieving over 31% DC efficiency at near PVUSA test conditions. Inculcating this design into their next MegaModule is forthcoming, but the expected AC system field efficiency should be significantly higher than current 25% levels.

Unit Cost Analysis of PET-CT at an Apex Public Sector Health Care Institute in India.

PubMed

Gajuryal, S H; Daga, A; Siddharth, V; Bal, C S; Satpathy, S

2017-01-01

PET/CT scan service is one of the capital intensive and revenue-generating centres of a tertiary care hospital. The cost associated with the provisioning of PET services is dependent upon the unit costs of the resources consumed. The study aims to determine the cost of providing PET/CT Scan services in a hospital. This descriptive and observational study was conducted in the Department of Nuclear Medicine at a tertiary apex teaching hospital in New Delhi, India in the year 2014-15. Traditional costing methodology was used for calculating the unit cost of PET/CT scan service. The cost was calculated under two heads that is capital and operating cost. Annualized cost of capital assets was calculated using methodology prescribed by WHO and operating costs was taken on an actual basis. Average number of PET/CT scan performed in a day is 30. The annual cost of providing PET/CT scan services was calculated to be 65,311,719 Indian Rupees (INR) (US$ 1,020,496), while the unit cost of PET scan was calculated to be 9625.92 INR (US$ 150). 3/4th cost was spent on machinery and equipment (75.3%) followed by healthcare personnel (11.37%), electricity (5%), consumables and supplies (4%) engineering maintenance (3.24%), building, furniture and HVAC capital cost (0.76%), and manifold cost (0.05%). Of the total cost, 76% was capital cost while the remaining was operating cost. Total cost for establishing PET/CT scan facility with cyclotron and chemistry module and PET/CT scan without cyclotron and chemistry module was calculated to be INR 610,873,517 (US$9944899) and 226,745,158 (US$3542893), respectively. (US$ 1=INR 64).

Life-cycle costs of high-performance cells

NASA Technical Reports Server (NTRS)

Daniel, R.; Burger, D.; Reiter, L.

1985-01-01

A life cycle cost analysis of high efficiency cells was presented. Although high efficiency cells produce more power, they also cost more to make and are more susceptible to array hot-spot heating. Three different computer analysis programs were used: SAMICS (solar array manufacturing industry costing standards), PVARRAY (an array failure mode/degradation simulator), and LCP (lifetime cost and performance). The high efficiency cell modules were found to be more economical in this study, but parallel redundancy is recommended.

G-protein signaling modulator 1 deficiency accelerates cystic disease in an orthologous mouse model of autosomal dominant polycystic kidney disease

PubMed Central

Kwon, Michelle; Pavlov, Tengis S.; Nozu, Kandai; Rasmussen, Shauna A.; Ilatovskaya, Daria V.; Lerch-Gaggl, Alexandra; North, Lauren M.; Kim, Hyunho; Qian, Feng; Sweeney, William E.; Avner, Ellis D.; Blumer, Joe B.; Staruschenko, Alexander; Park, Frank

2012-01-01

Polycystic kidney diseases are the most common genetic diseases that affect the kidney. There remains a paucity of information regarding mechanisms by which G proteins are regulated in the context of polycystic kidney disease to promote abnormal epithelial cell expansion and cystogenesis. In this study, we describe a functional role for the accessory protein, G-protein signaling modulator 1 (GPSM1), also known as activator of G-protein signaling 3, to act as a modulator of cyst progression in an orthologous mouse model of autosomal dominant polycystic kidney disease (ADPKD). A complete loss of Gpsm1 in the Pkd1V/V mouse model of ADPKD, which displays a hypomorphic phenotype of polycystin-1, demonstrated increased cyst progression and reduced renal function compared with age-matched cystic Gpsm1+/+ and Gpsm1+/− mice. Electrophysiological studies identified a role by which GPSM1 increased heteromeric polycystin-1/polycystin-2 ion channel activity via Gβγ subunits. In summary, the present study demonstrates an important role for GPSM1 in controlling the dynamics of cyst progression in an orthologous mouse model of ADPKD and presents a therapeutic target for drug development in the treatment of this costly disease. PMID:23236168

Multi-position photovoltaic assembly

DOEpatents

Dinwoodie, Thomas L.

2003-03-18

The invention is directed to a PV assembly, for use on a support surface, comprising a base, a PV module, a multi-position module support assembly, securing the module to the base at shipping and inclined-use angles, a deflector, a multi-position deflector support securing the deflector to the base at deflector shipping and deflector inclined-use angles, the module and deflector having opposed edges defining a gap therebetween. The invention permits transport of the PV assemblies in a relatively compact form, thus lowering shipping costs, while facilitating installation of the PV assemblies with the PV module at the proper inclination.

Photovoltaic module hot spot durability design and test methods

NASA Technical Reports Server (NTRS)

Arnett, J. C.; Gonzalez, C. C.

1981-01-01

As part of the Jet Propulsion Laboratory's Low-Cost Solar Array Project, the susceptibility of fat-plate modules to hot-spot problems is investigated. Hot-spot problems arise in modules when the cells become back-biased and operate in the negative-voltage quadrant, as a result of short-circuit current mismatch, cell cracking or shadowing. The details of a qualification test for determining the capability of modules of surviving field hot-spot problems and typical results of this test are presented. In addition, recommended circuit-design techniques for improving the module and array reliability with respect to hot-spot problems are presented.

Advanced photovoltaic concentrator system low-cost prototype module

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaminar, N.R.; McEntee, J.; Curchod, D.

1991-09-01

This report describes the continued development of an extruded lens and the development of a PV receiver, both of which will be used in the Solar Engineering Applications Corporation (SEA) 10X concentrator. These efforts were pare of a pre-Concentrator Initiative Program. The 10X concentrator consists of an inexpensive, extruded linear Fresnel lens which focuses on one-sun cells which are adhesive-bonded to an anodized aluminum heat sink. Module sides are planned to be molded along with the lens and are internally reflective for improved on- and off-track performance. End caps with molded-in bearings complete the module. Ten modules are mounted inmore » a stationary frame for simple, single-axis tracking in the east-west direction. This configuration an array, is shipped completely assembled and requires only setting on a reasonably flat surface, installing 4 fasteners, and hooking up the wires. Development of the 10-inch wide extruded lens involved one new extrusion die and a series of modifications to this die. Over 76% lens transmission was measured which surpassed the program goal of 75%. One-foot long receiver sections were assembled and subjected to evaluation tests at Sandia National Laboratories. A first group had some problem with cell delamination and voids but a second group performed very well, indicating that a full size receiver would pass the full qualification test. Cost information was updated and presented in the report. The cost study indicated that the Solar Engineering Applications Corporation concentrator system can exceed the DOE electricity cost goals of less than 6cents per KW-hr. 33 figs., 11 tabs.« less

Orion: Design of a system for assured low-cost human access to space

NASA Technical Reports Server (NTRS)

Elvander, Josh; Heifetz, Andy; Hunt, Teresa; Zhu, Martin

1994-01-01

In recent years, Congress and the American people have begun to seriously question the role and importance of future manned spaceflight. This is mainly due to two factors: a decline in technical competition caused by the collapse of communism, and the high costs associated with the Space Shuttle transportation system. With these factors in mind, the ORION system was designed to enable manned spaceflight at a low cost, while maintaining the ability to carry out diverse missions, each with a high degree of flexibility. It is capable of performing satellite servicing missions, supporting a space station via crew rotation and resupply, and delivering satellites into geosynchronous orbit. The components of the system are a primary launch module, an upper stage, and a manned spacecraft capable of dynamic reentry. For satellite servicing and space station resupply missions, the ORION system utilizes three primary modules, an upper stage, and the spacecraft, which is delivered to low earth orbit and used to rendezvous, transfer materials, and make repairs. For launching a geosynchronous satellite, one primary module and an upper stage are used to deliver the satellite, along with an apogee kick motor, into orbit. The system is designed with reusability and modularity in mind in an attempt to lower cost.

Modeling and Simulation Reliable Spacecraft On-Board Computing

NASA Technical Reports Server (NTRS)

Park, Nohpill

1999-01-01

The proposed project will investigate modeling and simulation-driven testing and fault tolerance schemes for Spacecraft On-Board Computing, thereby achieving reliable spacecraft telecommunication. A spacecraft communication system has inherent capabilities of providing multipoint and broadcast transmission, connectivity between any two distant nodes within a wide-area coverage, quick network configuration /reconfiguration, rapid allocation of space segment capacity, and distance-insensitive cost. To realize the capabilities above mentioned, both the size and cost of the ground-station terminals have to be reduced by using reliable, high-throughput, fast and cost-effective on-board computing system which has been known to be a critical contributor to the overall performance of space mission deployment. Controlled vulnerability of mission data (measured in sensitivity), improved performance (measured in throughput and delay) and fault tolerance (measured in reliability) are some of the most important features of these systems. The system should be thoroughly tested and diagnosed before employing a fault tolerance into the system. Testing and fault tolerance strategies should be driven by accurate performance models (i.e. throughput, delay, reliability and sensitivity) to find an optimal solution in terms of reliability and cost. The modeling and simulation tools will be integrated with a system architecture module, a testing module and a module for fault tolerance all of which interacting through a centered graphical user interface.

Bidirectional optical subassembly-shaped 20-Gbit/s compact single-mode four-channel wavelength-division multiplexing optical modules for optical multimedia interfaces

NASA Astrophysics Data System (ADS)

Lim, Kwon-Seob; Yu, Hong-Yeon; Park, Hyoung-Jun; Kang, Hyun Seo; Jang, Jae-Hyung

2016-06-01

Low-cost single-mode four-channel optical transmitter and receiver modules using the wavelength-division multiplexing (WDM) method have been developed for long-reach fiber optic applications. The single-mode four-channel WDM optical transmitter and receiver modules consist of two dual-wavelength optical transmitter and receiver submodules, respectively. The integration of two channels in a glass-sealed transistor outline-can package is an effective way to reduce cost and size and to extend the number of channels. The clear eye diagrams with more than about 6 dB of the extinction ratio and the minimum receiver sensitivity of lower than -16 dBm at a bit error rate of 10-12 have been obtained for the transmitter and receiver modules, respectively, at 5 Gbps/channel. The 4K ultrahigh definition contents have been transmitted over a 1-km-long single-mode fiber using a pair of proposed four-channel transmitter optical subassembly and receiver optical subassembly.

VCSEL-based optical transceiver module operating at 25 Gb/s and using a single CMOS IC

NASA Astrophysics Data System (ADS)

Afriat, Gil; Horwitz, Lior; Lazar, Dror; Issachar, Assaf; Pogrebinsky, Alexander; Ran, Adee; Shoor, Ehud; Bar, Roi; Saba, Rushdy

2012-01-01

We present here a low cost, small form factor, optical transceiver module composed of a CMOS IC transceiver, 850 nm emission wavelength VCSEL modulated at 25 Gb/s, and an InGaAs/InP PIN Photo Diode (PD). The transceiver IC is fabricated in a standard 28 nm CMOS process and integrates the analog circuits interfacing the VCSEL and PD, namely the VCSEL driver and Transimpedance Amplifier (TIA), as well as all other required transmitter and receiver circuits like Phase Locked Loop (PLL), Post Amplifier and Clock & Data Recovery (CDR). The transceiver module couples into a 62.5/125 um multi-mode (OM1) TX/RX fiber pair via a low cost plastic cover realizing the transmitter and receiver lens systems and demonstrates BER < 10-12 at the 25 Gb/s data rate over a distance of 3 meters. Using a 50/125 um laser optimized multi-mode fiber (OM3), the same performance was achieved over a distance of 30 meters.

Low-cost mobile phone microscopy with a reversed mobile phone camera lens.

PubMed

Switz, Neil A; D'Ambrosio, Michael V; Fletcher, Daniel A

2014-01-01

The increasing capabilities and ubiquity of mobile phones and their associated digital cameras offer the possibility of extending low-cost, portable diagnostic microscopy to underserved and low-resource areas. However, mobile phone microscopes created by adding magnifying optics to the phone's camera module have been unable to make use of the full image sensor due to the specialized design of the embedded camera lens, exacerbating the tradeoff between resolution and field of view inherent to optical systems. This tradeoff is acutely felt for diagnostic applications, where the speed and cost of image-based diagnosis is related to the area of the sample that can be viewed at sufficient resolution. Here we present a simple and low-cost approach to mobile phone microscopy that uses a reversed mobile phone camera lens added to an intact mobile phone to enable high quality imaging over a significantly larger field of view than standard microscopy. We demonstrate use of the reversed lens mobile phone microscope to identify red and white blood cells in blood smears and soil-transmitted helminth eggs in stool samples.

Low-Cost Mobile Phone Microscopy with a Reversed Mobile Phone Camera Lens

PubMed Central

Fletcher, Daniel A.

2014-01-01

The increasing capabilities and ubiquity of mobile phones and their associated digital cameras offer the possibility of extending low-cost, portable diagnostic microscopy to underserved and low-resource areas. However, mobile phone microscopes created by adding magnifying optics to the phone's camera module have been unable to make use of the full image sensor due to the specialized design of the embedded camera lens, exacerbating the tradeoff between resolution and field of view inherent to optical systems. This tradeoff is acutely felt for diagnostic applications, where the speed and cost of image-based diagnosis is related to the area of the sample that can be viewed at sufficient resolution. Here we present a simple and low-cost approach to mobile phone microscopy that uses a reversed mobile phone camera lens added to an intact mobile phone to enable high quality imaging over a significantly larger field of view than standard microscopy. We demonstrate use of the reversed lens mobile phone microscope to identify red and white blood cells in blood smears and soil-transmitted helminth eggs in stool samples. PMID:24854188

A Low-Cost Time-Resolved Spectrometer for the Study of Ruby Emission

ERIC Educational Resources Information Center

McBane, George C.; Cannella, Christian; Schaertel, Stephanie

2018-01-01

A low-cost time-resolved emission spectrometer optimized for ruby emission is presented. The use of a Class II diode laser module as the excitation source reduces costs and hazards. The design presented here can facilitate the inclusion of time-resolved emission spectroscopy with laser excitation sources in the undergraduate laboratory curriculum.…

Accurate and cost-effective MTF measurement system for lens modules of digital cameras

NASA Astrophysics Data System (ADS)

Chang, Gao-Wei; Liao, Chia-Cheng; Yeh, Zong-Mu

2007-01-01

For many years, the widening use of digital imaging products, e.g., digital cameras, has given rise to much attention in the market of consumer electronics. However, it is important to measure and enhance the imaging performance of the digital ones, compared to that of conventional cameras (with photographic films). For example, the effect of diffraction arising from the miniaturization of the optical modules tends to decrease the image resolution. As a figure of merit, modulation transfer function (MTF) has been broadly employed to estimate the image quality. Therefore, the objective of this paper is to design and implement an accurate and cost-effective MTF measurement system for the digital camera. Once the MTF of the sensor array is provided, that of the optical module can be then obtained. In this approach, a spatial light modulator (SLM) is employed to modulate the spatial frequency of light emitted from the light-source. The modulated light going through the camera under test is consecutively detected by the sensors. The corresponding images formed from the camera are acquired by a computer and then, they are processed by an algorithm for computing the MTF. Finally, through the investigation on the measurement accuracy from various methods, such as from bar-target and spread-function methods, it appears that our approach gives quite satisfactory results.

GloSensor assay for discovery of GPCR-selective ligands.

PubMed

Kumar, Boda Arun; Kumari, Poonam; Sona, Chandan; Yadav, Prem N

2017-01-01

G protein-coupled receptors (GPCRs) are modulators of almost every physiological process, and therefore, are most favorite therapeutic target for wide spectrum of diseases. Ideally, high-throughput functional assays should be implemented that allow the screening of large compound libraries in cost-effective manner to identify agonist, antagonist, and allosteric modulators in the same assay. Taking advantage of the increased understanding of the GPCR structure and signaling, several commercially available functional assays based on fluorescence or chemiluminescence detection are being used in both academia and industry. In this chapter, we provide step-by-step method and guidelines to perform cAMP measurement using GloSensor assay. Finally, we have also discussed the analysis and interpretation of results obtained using this assay by providing several examples of G s - and G i -coupled GPCRs. © 2017 Elsevier Inc. All rights reserved.

Results of module electrical measurement of the DOE 46-kilowatt procurement

NASA Technical Reports Server (NTRS)

Curtis, H. B.

1978-01-01

Current-voltage measurements have been made on terrestrial solar cell modules of the DOE/JPL Low Cost Silicon Solar Array procurement. Data on short circuit current, open circuit voltage, and maximum power for the four types of modules are presented in normalized form, showing distribution of the measured values. Standard deviations from the mean values are also given. Tests of the statistical significance of the data are discussed.

Feasibility study of the design of Bi Ra Systems, Incorporated model 5301, 5101, and 3222 CAMAC modules for space use

NASA Technical Reports Server (NTRS)

Biswell, L.; Mcelderry, R.

1976-01-01

Cost estimates are determined for redesigned modules. Consideration is given to incorporation of NASA approved components, component screening and documentation, as well as reduced power consumption. Results show that r designed modules will function reliably in a space environment of 50 C and withstand greater than 15 G's of random vibration between 40 Hz and 400 Hz.

A prospective audit on the effect of training and educational workshops on the incidence of urethral catheterization injuries

PubMed Central

Bhatt, Nikita R.; Davis, Niall F.; Quinlan, Mark R.; Flynn, Robert J.; McDermott, T.E.D.; Manecksha, Rustom P.; Thornhill, John A.

2017-01-01

Introduction The incidence of iatrogenic urethral catheterization (UC) injuries is approximately 0.3%. Resultant complications are associated with patient morbidity and unnecessary healthcare costs. Our aim was to investigate whether educational training workshops decreased the incidence of UC-related injuries. Methods A prospective audit was performed to calculate incidence, morbidity, and costs associated with iatrogenic UC injury from January to July 2015. Educational workshops were then conducted with healthcare staff and training modules for junior doctors. UC-related incidence, morbidity, and costs in the subsequent six-month period were recorded prospectively and compared with the previous data. Results The incidence of iatrogenic UC injuries was reduced from 4.3/1000 catheters inserted to 3.8/1000 catheters after the intervention (p=0.59). Morbidity from UC increased in the second half in the form of increase in cumulative additional inpatient hospital stay (22 to 79 days; p=0.25), incidence of urosepsis (n=2 to n=4), and need for operative intervention (n=1 to n=2). The cost of managing UC injuries almost doubled in the period after the training intervention (€50 449 to €90 100). Conclusions Current forms of educational and training interventions for UC did not significantly change morbidity or cost of iatrogenic UC injuries despite a decrease in incidence. Improved and intensive training protocols are necessary for UC to prevent avoidable iatrogenic complications, as well as a safer urethral catheter design. PMID:28761592

Prototype Solid State Induction Modulator for SLAC NLC

NASA Astrophysics Data System (ADS)

Cassel, R. L.; DeLamare, J. E.; Nguyen, M. N.; Pappas, G. C.; Cook, E.

2002-08-01

The Next Linear Collider accelerator proposal at SLAC requires a high efficiency, highly reliable, and low cost pulsed power modulator to drive the X band klystrons. The present NLC envisions a solid-state induction modulator design to drive up to 8 klystrons to 500kV for 3muS at 120 PPS with one modulator (>1,000 megawatt pulse, 500kW average). A prototype modulator is presently under construction, which well power 4 each 5045 SLAC klystron to greater than 380 kV for 3muS (>600 megawatt pulse, >300 kW Ave.). The modulator will be capable of driving the 8 each X band klystrons when they become available. The paper covers the design, construction, fabrication and preliminary testing of the prototype modulator.

Development of low cost custom hybrid microcircuit technology

NASA Technical Reports Server (NTRS)

Perkins, K. L.; Licari, J. J.

1981-01-01

Selected potentially low cost, alternate packaging and interconnection techniques were developed and implemented in the manufacture of specific NASA/MSFC hardware, and the actual cost savings achieved by their use. The hardware chosen as the test bed for this evaluation ws the hybrids and modules manufactured by Rockwell International fo the MSFC Flight Accelerometer Safety Cut-Off System (FASCOS). Three potentially low cost packaging and interconnection alternates were selected for evaluation. This study was performed in three phases: hardware fabrication and testing, cost comparison, and reliability evaluation.

Technical Review and Analysis of Center for Night Vision and Electro-Optics Life Cycle Cost Analysis Model (CNVEO LCCAM),

DTIC Science & Technology

1986-09-01

source of the module/system. Source options are; battery, gas, cartridge, valve , and miscellaneous costs. NAMELIST OPERAT is used to compile the...hardware costs allocated to transportation for packing. TF1 = Initial transportation factor. WEIGHT = Shipping weight of total system. XSUM = System float...CD(6,I)+CD(9,I). . AROC(7,I) - Replenishment spares by year. CD(4,I) - Valve replacement cost by year. CD(5,I) = Cartridge replacement cost by year

23 CFR 1252.5 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... module(s). If an employee is spending time on a combination of administration and planning functions and... allocate costs based on acutal time spent on an activity, the State highway safety agency must keep accurate time records showing the work activities for each employee. The State's record keeping system must...

A Module Experimental Process System Development Unit (MEPSDU)

NASA Technical Reports Server (NTRS)

1981-01-01

A cost effective process sequence and machinery for the production of flat plate photovoltaic modules are described. Cells were fabricated using the process sequence which was optimized, as was a lamination procedure. Insulator tapes and edge seal material were identified and tested. Encapsulation materials were evaluated.

Costs and benefits of adapting to river floods at the global scale

NASA Astrophysics Data System (ADS)

Ward, Philip; Aerts, Jeroen; Botzen, Wouter; Hallegatte, Stephane; Jongman, Brenden; Kind, Jarl; Scussolini, Paolo; Winsemius, Hessel

2015-04-01

It is well known that the economic losses associated with flooding are huge; for example in 2012 alone the economic losses from flooding exceeded 19 billion. As a result, different models have been developed to assess global scale flood risk. Recently, these have been used in several studies to assess current flood risk at the global scale, and to project how risk may increase as a result of climate change and/or socioeconomic development. In most regions, these studies show rapid increases in risk into the future, and therefore call for urgent adaptation. However, to date no studies have attempted to assess the costs of carrying out such adaptation, nor the benefits. In this paper, we therefore present the first global scale estimate of the costs and benefits of adapting to increased river flood risk caused by factors such as climate change and socioeconomic development. For this study, we concentrate on structural adaptation measures, such as dikes, designed to prevent flood hazard up to a certain design standard. We address two questions: 1. What would be the costs and benefits of maintaining current flood protection standards, accounting for future climate and socioeconomic change until 2100? 2. What flood protection standards would be required by 2100 to keep future flood risk constant at today's levels? And what would be the costs and benefits associated with this? In this paper, we will present our first global estimates of the costs and benefits of adaptation to increased flood risk, as well as maps of these findings per country and river basin. We present the results under 4 emission scenarios (RCPs), 5 socioeconomic scenarios (SSPs), and under several assumptions relating to total potential flood damages, discount rates, construction costs, maintenance costs, and so forth. The research was carried out using the GLOFRIS modelling cascade. This global flood risk model calculates flood risk in terms of annual expected damage, and has been developed and validated over the past few years. For this study we have extended GLOFRIS by developing a module that calculates the costs and benefits of adaptation by increasing dike flood protection standards. In brief, this is carried out by calculating, per cell, the length of dikes that would be required to provide flood protection, multiplying this with the change in dike height that would be required to offer a certain flood protection standard, and multiplying this with data on the costs of dike construction and maintenance.

Performance Evaluation of Low Cost LoRa Modules in IoT Applications

NASA Astrophysics Data System (ADS)

Daud, Shuhaizar; Shi Yang, Teoh; Asmi Romli, Muhamad; Awang Ahmad, Zahari; Mahrom, Norfadila; Raof, Rafikha Aliana A.

2018-03-01

LoRa is a low power long range wireless communication platform that is designed as an efficient communication platform for small, low powered devices. This makes it very suitable for battery powered devices and IoT implementation. This paper evaluates some low cost LoRa modules available on the market and their suitability, energy efficiency and performance during operation. Two low cost LoRa transceiver from Semtech Industries, the SX1272 and SX1278 were tested for their power consumption and maximum transmission range. This study have evaluated the two LoRa solutions and found that the SX1278 have a better transmission range and uses lower energy compared to the SX1272 thus making it more suitable for embedded implementation as a data gateway.

Quad-phased data mining modeling for dementia diagnosis.

PubMed

Bang, Sunjoo; Son, Sangjoon; Roh, Hyunwoong; Lee, Jihye; Bae, Sungyun; Lee, Kyungwon; Hong, Changhyung; Shin, Hyunjung

2017-05-18

The number of people with dementia is increasing along with people's ageing trend worldwide. Therefore, there are various researches to improve a dementia diagnosis process in the field of computer-aided diagnosis (CAD) technology. The most significant issue is that the evaluation processes by physician which is based on medical information for patients and questionnaire from their guardians are time consuming, subjective and prone to error. This problem can be solved by an overall data mining modeling, which subsidizes an intuitive decision of clinicians. Therefore, in this paper we propose a quad-phased data mining modeling consisting of 4 modules. In Proposer Module, significant diagnostic criteria are selected that are effective for diagnostics. Then in Predictor Module, a model is constructed to predict and diagnose dementia based on a machine learning algorism. To help clinical physicians understand results of the predictive model better, in Descriptor Module, we interpret causes of diagnostics by profiling patient groups. Lastly, in Visualization Module, we provide visualization to effectively explore characteristics of patient groups. The proposed model is applied for CREDOS study which contains clinical data collected from 37 university-affiliated hospitals in republic of Korea from year 2005 to 2013. This research is an intelligent system enabling intuitive collaboration between CAD system and physicians. And also, improved evaluation process is able to effectively reduce time and cost consuming for clinicians and patients.

Pulsed laser-based optical frequency comb generator for high capacity wavelength division multiplexed passive optical network supporting 1.2 Tbps

NASA Astrophysics Data System (ADS)

Ullah, Rahat; Liu, Bo; Zhang, Qi; Saad Khan, Muhammad; Ahmad, Ibrar; Ali, Amjad; Khan, Razaullah; Tian, Qinghua; Yan, Cheng; Xin, Xiangjun

2016-09-01

An architecture for flattened and broad spectrum multicarriers is presented by generating 60 comb lines from pulsed laser driven by user-defined bit stream in cascade with three modulators. The proposed scheme is a cost-effective architecture for optical line terminal (OLT) in wavelength division multiplexed passive optical network (WDM-PON) system. The optical frequency comb generator consists of a pulsed laser in cascade with a phase modulator and two Mach-Zehnder modulators driven by an RF source incorporating no phase shifter, filter, or electrical amplifier. Optical frequency comb generation is deployed in the simulation environment at OLT in WDM-PON system supports 1.2-Tbps data rate. With 10-GHz frequency spacing, each frequency tone carries data signal of 20 Gbps-based differential quadrature phase shift keying (DQPSK) in downlink transmission. We adopt DQPSK-based modulation technique in the downlink transmission because it supports 2 bits per symbol, which increases the data rate in WDM-PON system. Furthermore, DQPSK format is tolerant to different types of dispersions and has a high spectral efficiency with less complex configurations. Part of the downlink power is utilized in the uplink transmission; the uplink transmission is based on intensity modulated on-off keying. Minimum power penalties have been observed with excellent eye diagrams and other transmission performances at specified bit error rates.

Clock and trigger synchronization between several chassis of digital data acquisition modules

NASA Astrophysics Data System (ADS)

Hennig, W.; Tan, H.; Walby, M.; Grudberg, P.; Fallu-Labruyere, A.; Warburton, W. K.; Vaman, C.; Starosta, K.; Miller, D.

2007-08-01

In applications with segmented high purity Ge detectors or other detector arrays with tens or hundreds of channels, the high development cost and limited flexibility of application specific integrated circuits outweigh their benefits of low power and small size. The readout electronics typically consist of multi-channel data acquisition modules in a common chassis for power, clock and trigger distribution, and data readout. As arrays become larger and reach several hundred channels, the readout electronics have to be divided over several chassis, but still must maintain precise synchronization of clocks and trigger signals across all channels. This division becomes necessary not only because of limits given by the instrumentation standards on module size and chassis slot numbers, but also because data readout times increase when more modules share the same data bus and because power requirements approach the limits of readily available power supplies. In this paper, we present a method for distributing clocks and triggers between 4 PXI chassis containing DGF Pixie-16 modules with up to 226 acquisition channels per chassis. The data acquisition system is intended to instrument the over 600 channels of the SeGA detector array at the National Superconducting Cyclotron Laboratory. Our solution is designed to achieve synchronous acquisition of detector waveforms from all channels with a jitter of less than 1 ns, and can be extended to a larger number of chassis if desired.

Performance of a Prototype Stationary Catadioptric Concentrating Photovoltaic Module

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lloyd, John V.; Kozodoy, Peter; Gladden, Christopher

A stationary catadioptric concentrating photovoltaic module with aperture area over 100 cm2, geometric concentration of 180x, and collection within 60° of polar incidence was designed, prototyped, and characterized. The module performance followed modeling closely with a peak power conversion efficiency of 26% for direct irradiance. Tracking of the sun is accomplished via translational micro-tracking completely internal to the module, avoiding the cost and complexity of mechanical two-axis trackers that point towards the sun. This study demonstrates the potential for concentrating photovoltaic modules with significantly higher efficiency than industry standard silicon photovoltaic modules that could be installed in stationary configurations onmore » rooftops.« less

Performance of a Prototype Stationary Catadioptric Concentrating Photovoltaic Module

DOE PAGES

Lloyd, John V.; Kozodoy, Peter; Gladden, Christopher; ...

2018-03-28

A stationary catadioptric concentrating photovoltaic module with aperture area over 100 cm2, geometric concentration of 180x, and collection within 60° of polar incidence was designed, prototyped, and characterized. The module performance followed modeling closely with a peak power conversion efficiency of 26% for direct irradiance. Tracking of the sun is accomplished via translational micro-tracking completely internal to the module, avoiding the cost and complexity of mechanical two-axis trackers that point towards the sun. This study demonstrates the potential for concentrating photovoltaic modules with significantly higher efficiency than industry standard silicon photovoltaic modules that could be installed in stationary configurations onmore » rooftops.« less

Individual quality and age but not environmental or social conditions modulate costs of reproduction in a capital breeder.

PubMed

Debeffe, Lucie; Poissant, Jocelyn; McLoughlin, Philip D

2017-08-01

Costs associated with reproduction are widely known to play a role in the evolution of reproductive tactics with consequences to population and eco-evolutionary dynamics. Evaluating these costs as they pertain to species in the wild remains an important goal of evolutionary ecology. Individual heterogeneity, including differences in individual quality (i.e., among-individual differences in traits associated with survival and reproduction) or state, and variation in environmental and social conditions can modulate the costs of reproduction; however, few studies have considered effects of these factors simultaneously. Taking advantage of a detailed, long-term dataset for a population of feral horses (Sable Island, Nova Scotia, Canada), we address the question of how intrinsic (quality, age), environmental (winter severity, location), and social conditions (group size, composition, sex ratio, density) influence the costs of reproduction on subsequent reproduction. Individual quality was measured using a multivariate analysis on a combination of four static and dynamic traits expected to depict heterogeneity in individual performance. Female quality and age interacted with reproductive status of the previous year to determine current reproductive effort, while no effect of social or environmental covariates was found. High-quality females showed higher probabilities of giving birth and weaning their foal regardless of their reproductive status the previous year, while those of lower quality showed lower probabilities of producing foals in successive years. Middle-aged (prime) females had the highest probability of giving birth when they had not reproduced the year before, but no such relationship with age was found among females that had reproduced the previous year, indicating that prime-aged females bear higher costs of reproduction. We show that individual quality and age were key factors modulating the costs of reproduction in a capital breeder but that environmental or social conditions were not, highlighting the importance of considering multiple factors when studying costs of reproduction.

Interactive internet-based clinical education: an efficient and cost-savings approach to point-of-care test training.

PubMed

Knapp, Herschel; Chan, Kee; Anaya, Henry D; Goetz, Matthew B

2011-06-01

We successfully created and implemented an effective HIV rapid testing training and certification curriculum using traditional in-person training at multiple sites within the U.S. Department of Veterans Affairs (VA) Healthcare System. Considering the multitude of geographically remote facilities in the nationwide VA system, coupled with the expansion of HIV diagnostics, we developed an alternate training method that is affordable, efficient, and effective. Using materials initially developed for in-person HIV rapid test in-services, we used a distance learning model to offer this training via live audiovisual online technology to educate clinicians at a remote outpatient primary care VA facility. Participants' evaluation metrics showed that this form of remote education is equivalent to in-person training; additionally, HIV testing rates increased considerably in the months following this intervention. Although there is a one-time setup cost associated with this remote training protocol, there is potential cost savings associated with the point-of-care nurse manager's time productivity by using the Internet in-service learning module for teaching HIV rapid testing. If additional in-service training modules are developed into Internet-based format, there is the potential for additional cost savings. Our cost analysis demonstrates that the remote in-service method provides a more affordable and efficient alternative compared with in-person training. The online in-service provided training that was equivalent to in-person sessions based on first-hand supervisor observation, participant satisfaction surveys, and follow-up results. This method saves time and money, requires fewer personnel, and affords access to expert trainers regardless of geographic location. Further, it is generalizable to training beyond HIV rapid testing. Based on these consistent implementation successes, we plan to expand use of online training to include remote VA satellite facilities spanning several states for a variety of diagnostic devices. Ultimately, Internet-based training has the potential to provide "big city" quality of care to patients at remote (rural) clinics.

Development of Nanosatellite Technology with APRS Module for Disaster Mitigation

NASA Astrophysics Data System (ADS)

Prahyang, S. Y.; Dhiya’Ulhaq, M. Z.; Golim, O. P.; Gunawan, R.; Suhandinata; Jahja, E.; Nelwan, E. R. G.; Ananta, C.; Chow, I. M.; Mali, N. D. F.

2018-05-01

Development of nanosatellite technology has enabled satellites to be developed with multiple capabilities for a specific mission in a short time with a low cost. Satellite communications are proved to be more effective in delivering information due to its large coverage area. Surya Satellite-1 will become the first Indonesian nanosatellite developed by undergraduate students. It is designed with low-cost commercial payloads, including an APRS module for communication and operated on VHF and UHF amateur radio frequencies. The mission of the satellites focused on disaster mitigation through APRS communication network with remote stations located on disaster-prone areas.

Impact: a low cost, reconfigurable, digital beamforming common module building block for next generation phased arrays

NASA Astrophysics Data System (ADS)

Paulsen, Lee; Hoffmann, Ted; Fulton, Caleb; Yeary, Mark; Saunders, Austin; Thompson, Dan; Chen, Bill; Guo, Alex; Murmann, Boris

2015-05-01

Phased array systems offer numerous advantages to the modern warfighter in multiple application spaces, including Radar, Electronic Warfare, Signals Intelligence, and Communications. However, a lack of commonality in the underlying technology base for DoD Phased Arrays has led to static systems with long development cycles, slow technology refreshes in response to emerging threats, and expensive, application-specific sub-components. The IMPACT module (Integrated Multi-use Phased Array Common Tile) is a multi-channel, reconfigurable, cost-effective beamformer that provides a common building block for multiple, disparate array applications.

Skew chicane based betatron eigenmode exchange module

DOEpatents

Douglas, David

2010-12-28

A skewed chicane eigenmode exchange module (SCEEM) that combines in a single beamline segment the separate functionalities of a skew quad eigenmode exchange module and a magnetic chicane. This module allows the exchange of independent betatron eigenmodes, alters electron beam orbit geometry, and provides longitudinal parameter control with dispersion management in a single beamline segment with stable betatron behavior. It thus reduces the spatial requirements for multiple beam dynamic functions, reduces required component counts and thus reduces costs, and allows the use of more compact accelerator configurations than prior art design methods.

Design and Implementation of a Wireless Sensor Network-Based Remote Water-Level Monitoring System

PubMed Central

Li, Xiuhong; Cheng, Xiao; Gong, Peng; Yan, Ke

2011-01-01

The proposed remote water-level monitoring system (RWMS) consists of a field sensor module, a base station module, adata center module and aWEB releasing module. It has advantages in real time and synchronized remote control, expandability, and anti-jamming capabilities. The RWMS can realize real-time remote monitoring, providing early warning of events and protection of the safety of monitoring personnel under certain dangerous circumstances. This system has been successfully applied in Poyanghu Lake. The cost of the whole system is approximately 1,500 yuan (RMB). PMID:22319377

Module Degradation Mechanisms Studied by a Multi-Scale Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnston, Steve; Al-Jassim, Mowafak; Hacke, Peter

2016-11-21

A key pathway to meeting the Department of Energy SunShot 2020 goals is to reduce financing costs by improving investor confidence through improved photovoltaic (PV) module reliability. A comprehensive approach to further understand and improve PV reliability includes characterization techniques and modeling from module to atomic scale. Imaging techniques, which include photoluminescence, electroluminescence, and lock-in thermography, are used to locate localized defects responsible for module degradation. Small area samples containing such defects are prepared using coring techniques and are then suitable and available for microscopic study and specific defect modeling and analysis.

Design and implementation of a wireless sensor network-based remote water-level monitoring system.

PubMed

Li, Xiuhong; Cheng, Xiao; Gong, Peng; Yan, Ke

2011-01-01

The proposed remote water-level monitoring system (RWMS) consists of a field sensor module, a base station module, a data center module and a WEB releasing module. It has advantages in real time and synchronized remote control, expandability, and anti-jamming capabilities. The RWMS can realize real-time remote monitoring, providing early warning of events and protection of the safety of monitoring personnel under certain dangerous circumstances. This system has been successfully applied in Poyanghu Lake. The cost of the whole system is approximately 1,500 yuan (RMB).

Energy production estimation for Kosh-Agach grid-tie photovoltaic power plant for different photovoltaic module types

NASA Astrophysics Data System (ADS)

Gabderakhmanova, T. S.; Kiseleva, S. V.; Frid, S. E.; Tarasenko, A. B.

2016-11-01

This paper is devoted to calculation of yearly energy production, demanded area and capital costs for first Russian 5 MW grid-tie photovoltaic (PV) plant in Altay Republic that is named Kosh-Agach. Simple linear calculation model, involving average solar radiation and temperature data, grid-tie inverter power-efficiency dependence and PV modules parameters is proposed. Monthly and yearly energy production, equipment costs and demanded area for PV plant are estimated for mono-, polycrystalline and amorphous modules. Calculation includes three types of initial radiation and temperature data—average day for every month from NASA SSE, average radiation and temperature for each day of the year from NASA POWER and typical meteorology year generated from average data for every month. The peculiarities for each type of initial data and their influence on results are discussed.

A Manufacturing Cost and Supply Chain Analysis of SiC Power Electronics Applicable to Medium-Voltage Motor Drives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horowitz, Kelsey; Remo, Timothy; Reese, Samantha

Wide bandgap (WBG) semiconductor devices are increasingly being considered for use in certain power electronics applications, where they can improve efficiency, performance, footprint, and, potentially, total system cost compared to systems using traditional silicon (Si) devices. Silicon carbide (SiC) devices in particular -- which are currently more mature than other WBG devices -- are poised for growth in the coming years. Today, the manufacturing of SiC wafers is concentrated in the United States, and chip production is split roughly equally between the United States, Japan, and Europe. Established contract manufacturers located throughout Asia typically carry out manufacturing of WBG powermore » modules. We seek to understand how global manufacturing of SiC components may evolve over time by illustrating the regional cost drivers along the supply chain and providing an overview of other factors that influence where manufacturing is sited. We conduct this analysis for a particular case study where SiC devices are used in a medium-voltage motor drive.« less

Effectiveness of low-cost electromagnetic shielding using nail-together galvanized steel: Test results. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, P.F.; Kennedy, E.L.; McCormack, R.G.

1992-09-01

The sensitivity of modern electronic equipment has increased the need for costly electromagnetic shielding. To reduce this cost, the U.S. Army Construction Engineering Research Laboratories (USACERL) has developed a new concept for shielding design that uses 28-gauge galvanized steel and standard galvanized nails. In this study, an electromagnetically shielded structure using the concept was designed, built, and evaluated for shielding effectiveness. The galvanized material was mounted to the standard USACERL test aperture and nailed to the wooden module frame, and the shielding effectiveness of the new construction design was measured using radio frequency antennas and receivers. Evaluations showed that themore » nail-together structure proved adequate for many shielding applications. However, while the galvanized steel met most shielding application requirements, this process added multiple seams to the structure, which decreased shielding in many instances by as much as 40 dB. Electromagnetic shielding, Electromagnetic pulse C3I Facilities.« less

Impact of automatic calibration techniques on HMD life cycle costs and sustainable performance

NASA Astrophysics Data System (ADS)

Speck, Richard P.; Herz, Norman E., Jr.

2000-06-01

Automatic test and calibration has become a valuable feature in many consumer products--ranging from antilock braking systems to auto-tune TVs. This paper discusses HMDs (Helmet Mounted Displays) and how similar techniques can reduce life cycle costs and increase sustainable performance if they are integrated into a program early enough. Optical ATE (Automatic Test Equipment) is already zeroing distortion in the HMDs and thereby making binocular displays a practical reality. A suitcase sized, field portable optical ATE unit could re-zero these errors in the Ready Room to cancel the effects of aging, minor damage and component replacement. Planning on this would yield large savings through relaxed component specifications and reduced logistic costs. Yet, the sustained performance would far exceed that attained with fixed calibration strategies. Major tactical benefits can come from reducing display errors, particularly in information fusion modules and virtual `beyond visual range' operations. Some versions of the ATE described are in production and examples of high resolution optical test data will be discussed.

Economic and practical challenges to the formulation of vaccines against endemic infectious diseases such as malaria.

PubMed

Plebanski, Magdalena; Lopez, Ester; Proudfoot, Owen; Cooke, Brian M; Itzstein, Mark von; Coppel, Ross L

2006-09-01

Herein, we analyze in general the current vaccine market and identify potential factors driving and modulating supply and demand for vaccines. An emphasis is placed on changes in regulation in the last 20 years which have led to increased indirect costs of production, and which can create a barrier against the timely use of technological advances to reduce direct costs. Other defining industry characteristics, such as firm numbers and sizes, cost and pricing strategies, nature extent and impact of Government involvement and international regulation are noted. These considerations, far from being removed from basic vaccine research, influence its ability to achieve aims that can be then progressed into effective vaccine products. We discuss specifically the development of particulate vaccines against malaria, a major lethal disease and health problem prevalent in Africa, including some key economic and methodological challenges and opportunities. We note some practical issues blocking the development of effective particulate vaccines for the Third World, mainly driven by the regulatory spiral noted above.

Silicon wafer-based tandem cells: The ultimate photovoltaic solution?

NASA Astrophysics Data System (ADS)

Green, Martin A.

2014-03-01

Recent large price reductions with wafer-based cells have increased the difficulty of dislodging silicon solar cell technology from its dominant market position. With market leaders expected to be manufacturing modules above 16% efficiency at 0.36/Watt by 2017, even the cost per unit area (60-70/m2) will be difficult for any thin-film photovoltaic technology to significantly undercut. This may make dislodgement likely only by appreciably higher energy conversion efficiency approaches. A silicon wafer-based cell able to capitalize on on-going cost reductions within the mainstream industry, but with an appreciably higher than present efficiency, might therefore provide the ultimate PV solution. With average selling prices of 156 mm quasi-square monocrystalline Si photovoltaic wafers recently approaching 1 (per wafer), wafers now provide clean, low cost templates for overgrowth of thin, wider bandgap high performance cells, nearly doubling silicon's ultimate efficiency potential. The range of possible Si-based tandem approaches is reviewed together with recent results and ultimate prospects.

The possibility of developing hybrid PV/T solar system

NASA Astrophysics Data System (ADS)

Dobrnjac, M.; Zivkovic, P.; Babic, V.

2017-05-01

An alternative and cost-effective solution to developing integrated PV system is to use hybrid photovoltaic/thermal (PV/T) solar system. The temperature of PV modules increases due to the absorbed solar radiation that is not converted into electricity, causing a decrease in their efficiency. In hybrid PV/T solar systems the reduction of PV module temperature can be combined with a useful fluid heating. In this paper we present the possibility of developing a new hybrid PV/T solar system. Hybrid PV/T system can provide electrical and thermal energy, thus achieving a higher energy conversion rate of the absorbed solar radiation. We developed PV/T prototype consisted of commercial PV module and thermal panel with our original solution of aluminium absorber with special geometric shapes. The main advantages of our combined PV/T system are: removing of heat from the PV panel; extending the lifetime of photovoltaic cells; excess of the removing heat from PV part is used to heat the fluid in the thermal part of the panel; the possibility of using on the roof and facade constructions because less weight.

Fully automated synthesis of [(18) F]fluoro-dihydrotestosterone ([(18) F]FDHT) using the FlexLab module.

PubMed

Ackermann, Uwe; Lewis, Jason S; Young, Kenneth; Morris, Michael J; Weickhardt, Andrew; Davis, Ian D; Scott, Andrew M

2016-08-01

Imaging of androgen receptor expression in prostate cancer using F-18 FDHT is becoming increasingly popular. With the radiolabelling precursor now commercially available, developing a fully automated synthesis of [(18) F] FDHT is important. We have fully automated the synthesis of F-18 FDHT using the iPhase FlexLab module using only commercially available components. Total synthesis time was 90 min, radiochemical yields were 25-33% (n = 11). Radiochemical purity of the final formulation was > 99% and specific activity was > 18.5 GBq/µmol for all batches. This method can be up-scaled as desired, thus making it possible to study multiple patients in a day. Furthermore, our procedure uses 4 mg of precursor only and is therefore cost-effective. The synthesis has now been validated at Austin Health and is currently used for [(18) F]FDHT studies in patients. We believe that this method can easily adapted by other modules to further widen the availability of [(18) F]FDHT. Copyright © 2016 John Wiley & Sons, Ltd.

Module-Based Professional Development for Teachers: A Cost-Effective Philippine Experiment

ERIC Educational Resources Information Center

San Antonio, Diosdado M.; Morales, Nelson S.; Moral, Leo S.

2011-01-01

This article examines the impact of implementing module-based professional development for teachers (MBPDT) in the Philippines. A mixed-method study, experimental design with empirical surveys and an open-ended questionnaire revealed that the experimental group of teachers had greater professional content knowledge compared with the control group…

A Modern and Interactive Approach to Learning Laser and Optical Communications.

ERIC Educational Resources Information Center

Minasian, Robert; Alameh, Kamal

2002-01-01

Discusses challenges in teaching lasers and optical communications to engineers, including the prohibitive cost of laboratory experiments, and describes the development of a computer-based photonics simulation experiment module which provides students with an understanding and visualization of how lasers can be modulated in telecommunications.…

Coding and Modulation for LMDS and Analysis of the LMDS Channel

PubMed Central

Håkegård, Jan Erik

2000-01-01

Local Multipoint Distribution Service (LMDS) has the potential to become a viable alternative to coaxial cable, fiber and other wired and wireless technologies providing “last mile” communication services. A major obstacle, however, is the high equipment cost. While for example cable modems supporting two-way services are available for $200 to $300, LMDS modem providing similar services will cost over $1000. The major cost driver of LMDS equipment is the radio frequency (RF) unit, as Ka-band technology still is quite expensive. The modem design must minimize the overall architecture cost, and low-cost modems requiring an expensive architecture should not be used. The channel characteristics of LMDS systems are very different from those of fiber, coaxial cable, and lower frequency wireless links, major channel impairments being non-linear high power amplifier (HPA), high phase noise and high co-channel interference. Modems should therefore be developed specifically for LMDS systems. This report deals with the choice of coding and modulation schemes, the LMDS channel, and how the channel impairments should be overcome by digital signal processing algorithms. PMID:27551634

Neural basis of increased costly norm enforcement under adversity.

PubMed

Wu, Yan; Yu, Hongbo; Shen, Bo; Yu, Rongjun; Zhou, Zhiheng; Zhang, Guoping; Jiang, Yushi; Zhou, Xiaolin

2014-12-01

Humans are willing to punish norm violations even at a substantial personal cost. Using fMRI and a variant of the ultimatum game and functional magnetic resonance imaging, we investigated how the brain differentially responds to fairness in loss and gain domains. Participants (responders) received offers from anonymous partners indicating a division of an amount of monetary gain or loss. If they accept, both get their shares according to the division; if they reject, both get nothing or lose the entire stake. We used a computational model to derive perceived fairness of offers and participant-specific inequity aversion. Behaviorally, participants were more likely to reject unfair offers in the loss (vs gain) domain. Neurally, the positive correlation between fairness and activation in ventral striatum was reduced, whereas the negative correlations between fairness and activations in dorsolateral prefrontal cortex were enhanced in the loss domain. Moreover, rejection-related dorsal striatum activation was higher in the loss domain. Furthermore, the gain-loss domain modulates costly punishment only when unfair behavior was directed toward the participants and not when it was directed toward others. These findings provide neural and computational accounts of increased costly norm enforcement under adversity and advanced our understanding of the context-dependent nature of fairness preference. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

The System Design, Engineering Architecture, and Preliminary Results of a Lower-Cost High-Sensitivity High-Resolution Positron Emission Mammography Camera.

PubMed

Zhang, Yuxuan; Ramirez, Rocio A; Li, Hongdi; Liu, Shitao; An, Shaohui; Wang, Chao; Baghaei, Hossain; Wong, Wai-Hoi

2010-02-01

A lower-cost high-sensitivity high-resolution positron emission mammography (PEM) camera is developed. It consists of two detector modules with the planar detector bank of 20 × 12 cm(2). Each bank has 60 low-cost PMT-Quadrant-Sharing (PQS) LYSO blocks arranged in a 10 × 6 array with two types of geometries. One is the symmetric 19.36 × 19.36 mm(2) block made of 1.5 × 1.5 × 10 mm(3) crystals in a 12 × 12 array. The other is the 19.36 × 26.05 mm(2) asymmetric block made of 1.5 × 1.9 × 10 mm(3) crystals in 12 × 13 array. One row (10) of the elongated blocks are used along one side of the bank to reclaim the half empty PMT photocathode in the regular PQS design to reduce the dead area at the edge of the module. The bank has a high overall crystal packing fraction of 88%, which results in a very high sensitivity. Mechanical design and electronics have been developed for low-cost, compactness, and stability purposes. Each module has four Anger-HYPER decoding electronics that can handle a count-rate of 3 Mcps for single events. A simple two-module coincidence board with a hardware delay window for random coincidences has been developed with an adjustable window of 6 to 15 ns. Some of the performance parameters have been studied by preliminary tests and Monte Carlo simulations, including the crystal decoding map and the 17% energy resolution of the detectors, the point source sensitivity of 11.5% with 50 mm bank-to-bank distance, the 1.2 mm-spatial resolutions, 42 kcps peak Noise Equivalent Count Rate at 7.0-mCi total activity in human body, and the resolution phantom images. Those results show that the design goal of building a lower-cost, high-sensitivity, high-resolution PEM detector is achieved.

Thermionic modules

DOEpatents

King, Donald B.; Sadwick, Laurence P.; Wernsman, Bernard R.

2002-06-18

Modules of assembled microminiature thermionic converters (MTCs) having high energy-conversion efficiencies and variable operating temperatures manufactured using MEMS manufacturing techniques including chemical vapor deposition. The MTCs incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. The MTCs also exhibit maximum efficiencies of just under 30%, and thousands of the devices and modules can be fabricated at modest costs.

Five Applications of Max-Min Theory from Calculus. Applications of Max-Min Theory. Modules and Monographs in Undergraduate Mathematics and Its Applications. UMAP Module 341.

ERIC Educational Resources Information Center

Whitley, W. Thurmon

The emphasis is on so-called "best solution" problems to questions that frequently arise in practical situations, such as finding an answer for the least amount of time, greatest volume, least amount of work, maximum profit, and minimum cost. One of this module's purposes is to help users become acquainted with the types of calculations necessary…

Robustness of 40 Gb/s ASK modulation formats in the practical system infrastructure

NASA Astrophysics Data System (ADS)

Pincemin, Erwan; Tan, Antoine; Bezard, Aude; Tonello, Alessandro; Wabnitz, Stefano; Ania-Castañòn, Juan-Diego; Turitsyn, Sergei

2006-12-01

In this work, we theoretically and experimentally analyzed the resilience of 40 Gb/s amplitude shift keying modulation formats to transmission impairments in standard single-mode fiber lines as well as to optical filtering introduced by the optical add/drop multiplexer cascade. Our study is a pre-requisite to assess the implementation of cost-effective 40 Gb/s modulation technology in next generation high bit-rate robust optical transport networks.

How could the family-scale photovoltaic module help the poor farmer out of poverty and reduce CO2 emission?

NASA Astrophysics Data System (ADS)

Qiu, Xu; Jin, Ran

2016-04-01

China, the world's most populous country, is facing great opportunities and challenges. On the one hand, China's increasing economy is raising hundreds of millions of people out of poverty. On the other hand, there are still 100 million of whose daily income is less than 1 US dollar. In addition, China is the world's largest solar panel producer and also the largest emitter of greenhouse gases. Could we find a feasible way to use solar panels to help the poor and meanwhile reduce CO2 emissions? To do this, we reviewed the literature and investigated the related field sites and institutions in China. Results show that the extension of family-scale photovoltaic modules to countryside could help. The 3 kW-module is recommended for widely distribution because its technology is mature and the cost is relatively low (3500 US dollars). Besides their own use to improve their living standard, farmers can sell the excess electricity to the grid at the price of 0.17 UD/kWh. The farmer's annual income could be increased by 460-615 US dollars by selling electricity, and this is equivalent to half of their annual income in many rural regions. The photovoltaic module can be used for 25 years and the payback period is 7 years. In addition to its economic benefit, the photovoltaic module can reduce CO2 emissions by 0.93 kg/kWh. This is equivalent to annual reduction of 3000-4000 kg CO2 per family. Therefore, it is concluded that the family-scale photovoltaic module not only can help the farmers out of poverty but also can reduce CO2 emissions significantly. To promote its sustainable development, it is worthwhile to further investigations its business models as well as the effects of long-term support policies under different social and nature conditions.

Underwater Chaotic Lidar using Blue Laser Diodes

NASA Astrophysics Data System (ADS)

Rumbaugh, Luke K.

The thesis proposes and explores an underwater lidar system architecture based on chaotic modulation of recently introduced, commercially available, low cost blue laser diodes. This approach is experimentally shown to allow accurate underwater impulse response measurements while eliminating the need for several major components typically found in high-performance underwater lidar systems. The proposed approach is to: 1. Generate wideband, noise-like intensity modulation signals using optical chaotic modulation of blue-green laser diodes, and then 2. Use this signal source to develop an underwater chaotic lidar system that uses no electrical signal generator, no electro-optic modulator, no optical frequency doubler, and no large-aperture photodetector. The outcome of this thesis is the demonstration of a new underwater lidar system architecture that could allow high resolution ranging, imaging, and water profiling measurements in turbid water, at a reduced size, weight, power and cost relative to state-of-the-art high-performance underwater lidar sensors. This work also makes contributions to the state of the art in optics, nonlinear dynamics, and underwater sensing by demonstrating for the first time: 1. Wideband noise-like intensity modulation of a blue laser diode using no electrical signal generator or electro-optic modulator. Optical chaotic modulation of a 462 nm blue InGaN laser diode by self-feedback is explored for the first time. The usefulness of the signal to chaotic lidar is evaluated in terms of bandwidth, modulation depth, and autocorrelation peak-to-sidelobe-ratio (PSLR) using both computer and laboratory experiments. In laboratory experiments, the optical feedback technique is shown to be effective in generating wideband, noise-like chaotic signals with strong modulation depth when the diode is operated in an external-cavity dominated state. The modulation signal strength is shown to be limited by the onset of lasing within the diode's internal cavity. The possibility of overcoming this limit by increasing optical feedback strength is discussed. 2. Power scaling in the blue-green spectrum using no optical frequency doubler. Synchronization of two 462 nm blue InGaN laser diodes by bi-directional optical injection is demonstrated for the first time in laboratory experiments. The improvement in chaotic intensity modulation signal strength is demonstrated to be 2.5x over the single-diode case. The signal strength is again shown to be limited by the onset of internal cavity lasing. The synchronized-laser arrangement is shown to be theoretically equivalent to a single-diode scenario in which the optical feedback is amplified by 2x, supporting the idea that increased optical feedback strength can be used to scale optical chaotic modulation of InGaN diodes to high powers. 3. Underwater impulse response measurements using a calibrated chaotic lidar system. An underwater chaotic lidar system using two synchronized diodes as transmitters is demonstrated in laboratory experiments for the first time. Reflective impulse response measurements using the lidar system are made in free space, and in a variety of clear and turbid water conditions, using a quasi-monostatic (i.e. co-located transmitter and receiver) arrangement. A calibration routine is implemented that increases accuracy and instantaneous dynamic range of the impulse response measurement, resulting in a baseline temporal resolution of 750 ps and a PSLR of over 10 dB. The calibrated system is shown to be able to simultaneously measure localized and distributed reflections, and to allow separation of the localized ( i.e. surface and target) reflections from the distributed ( i.e. backscatter) returns in several domains. Accurate range measurement with sub-inch typical error is demonstrated in laboratory water tank tests, which show accurate measurement through >6 feet of turbid water, as limited by the experimental water tank setup. Strong performance to the limit of the setup is shown at dwell times down to 1 mus. 4. Range measurement through turbid water using no large-aperture photodetector. The possibility of using a synchronized optical receiver to make range measurements through an attenuating channel (i.e. turbid water) is tested using two InGaN diodes for the first time. Using a variable optical attenuator to simulate channel attenuation, synchronization is maintained through 30 dB channel attenuation in the current experimental setup. Distance measurements are demonstrated by using the output of only one of the two diodes, suggesting that this method could be used to measure distance between two bi-static (i.e. physically separated), cooperative chaotic lidar systems in some water conditions. This thesis concludes that the proposed approach is a feasible path to a novel high resolution underwater lidar sensor capable of operating in turbid water, which would have significant size, weight, power, and cost reductions because it would not use an electrical signal generator, an electro-optic modulator, or an optical frequency doubler. The work also suggests the possibility of range measurement in a limited range of water conditions using no large-aperture photodetector, most feasibly in a bi-static cooperative arrangement.

Development status of the heatpipe power and bimodal systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poston, David I.; Houts, Michael G.

1999-01-01

Space fission power systems can potentially enhance or enable ambitious lunar and Martian surface missions. Research into space fission power systems has been ongoing (at various levels) since the 1950s, but to date the United States (US) has flown only one space fission system, SNAP-10A, in 1965. Cost and development time have been significant reasons why space fission systems have not been used by the US. High cost and long development time are not inherent to the use of space fission power. However, high cost and long development time are inherent to any program that tries to do too muchmore » at once. Nearly all US space fission power programs have attempted to field systems capable of high power, even though more modest systems had not yet been flown. All of these programs have failed to fly a space fission system. Relatively low power (10 to 100 kWe) fission systems may be useful for near-term lunar and Martian surface missions, including missions in which in situ resource utilization is a priority. Such systems may also be useful for deep-space science missions and other missions. These systems can be significantly less expensive to develop than high power systems. Experience gained in the development of low-power space fission systems can then be used to enable cost-effective development of high-power ({gt}1000 kWe) fission systems. The Heatpipe Power System (HPS) is a potential, near-term, low-cost space fission power system. The Heatpipe Bimodal System (HBS) is a potential, near-term, low-cost space fission power and/or propulsion system. Both systems will be composed of independent modules, and all components use existing technology and operate within the existing database. The HPS and HBS have relatively few system integration issues; thus, the successful development of a module is a significant step toward verifying system feasibility and performance estimates. A prototypic HPS module was fabricated, and initial testing was completed in April 1997. All test objectives were accomplished, demonstrating the basic feasibility of the HPS. Fabrication of an HBS module is under way, and testing should begin in 1999. {copyright} {ital 1999 American Institute of Physics.}« less

Development status of the heatpipe power and bimodal systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poston, David I.; Houts, Michael G.; Emrich, William J. Jr.

1999-01-22

Space fission power systems can potentially enhance or enable ambitious lunar and Martian surface missions. Research into space fission power systems has been ongoing (at various levels) since the 1950s, but to date the United States (US) has flown only one space fission system, SNAP-10A, in 1965. Cost and development time have been significant reasons why space fission systems have not been used by the US. High cost and long development time are not inherent to the use of space fission power. However, high cost and long development time are inherent to any program that tries to do too muchmore » at once. Nearly all US space fission power programs have attempted to field systems capable of high power, even though more modest systems had not yet been flown. All of these programs have failed to fly a space fission system. Relatively low power (10 to 100 kWe) fission systems may be useful for near-term lunar and Martian surface missions, including missions in which in situ resource utilization is a priority. Such systems may also be useful for deep-space science missions and other missions. These systems can be significantly less expensive to develop than high power systems. Experience gained in the development of low-power space fission systems can then be used to enable cost-effective development of high-power (>1000 kWe) fission systems. The Heatpipe Power System (HPS) is a potential, near-term, low-cost space fission power system. The Heatpipe Bimodal System (HBS) is a potential, near-term, low-cost space fission power and/or propulsion system. Both systems will be composed of independent modules, and all components use existing technology and operate within the existing database. The HPS and HBS have relatively few system integration issues; thus, the successful development of a module is a significant step toward verifying system feasibility and performance estimates. A prototypic HPS module was fabricated, and initial testing was completed in April 1997. All test objectives were accomplished, demonstrating the basic feasibility of the HPS. Fabrication of an HBS module is under way, and testing should begin in 1999.« less

Development status of the heatpipe power and bimodal systems

NASA Astrophysics Data System (ADS)

Poston, David I.; Houts, Michael G.; Emrich, William J.

1999-01-01

Space fission power systems can potentially enhance or enable ambitious lunar and Martian surface missions. Research into space fission power systems has been ongoing (at various levels) since the 1950s, but to date the United States (US) has flown only one space fission system, SNAP-10A, in 1965. Cost and development time have been significant reasons why space fission systems have not been used by the US. High cost and long development time are not inherent to the use of space fission power. However, high cost and long development time are inherent to any program that tries to do too much at once. Nearly all US space fission power programs have attempted to field systems capable of high power, even though more modest systems had not yet been flown. All of these programs have failed to fly a space fission system. Relatively low power (10 to 100 kWe) fission systems may be useful for near-term lunar and Martian surface missions, including missions in which in situ resource utilization is a priority. Such systems may also be useful for deep-space science missions and other missions. These systems can be significantly less expensive to develop than high power systems. Experience gained in the development of low-power space fission systems can then be used to enable cost-effective development of high-power (>1000 kWe) fission systems. The Heatpipe Power System (HPS) is a potential, near-term, low-cost space fission power system. The Heatpipe Bimodal System (HBS) is a potential, near-term, low-cost space fission power and/or propulsion system. Both systems will be composed of independent modules, and all components use existing technology and operate within the existing database. The HPS and HBS have relatively few system integration issues; thus, the successful development of a module is a significant step toward verifying system feasibility and performance estimates. A prototypic HPS module was fabricated, and initial testing was completed in April 1997. All test objectives were accomplished, demonstrating the basic feasibility of the HPS. Fabrication of an HBS module is under way, and testing should begin in 1999.

Behavioral modeling of VCSELs for high-speed optical interconnects

NASA Astrophysics Data System (ADS)

Szczerba, Krzysztof; Kocot, Chris

2018-02-01

Transition from on-off keying to 4-level pulse amplitude modulation (PAM) in VCSEL based optical interconnects allows for an increase of data rates, at the cost of 4.8 dB sensitivity penalty. The resulting strained link budget creates a need for accurate VCSEL models for driver integrated circuit (IC) design and system level simulations. Rate equation based equivalent circuit models are convenient for the IC design, but system level analysis requires computationally efficient closed form behavioral models based Volterra series and neural networks. In this paper we present and compare these models.

Transparent Alloys Operation

NASA Image and Video Library

2018-03-26

iss055e005543 (March 26, 2018) --- Expedition 55 Flight Engineer and astronaut Scott Tingle is pictured conducting the Transparent Alloys experiment inside the Destiny lab module's Microgravity Science Glovebox. The Transparent Alloys study is a set of five experiments that seeks to improve the understanding of melting-solidification processes in plastics without the interference of Earth's gravity environment. Results may impact the development of new light-weight, high-performance structural materials for space applications. Observations may also impact fuel efficiency, consumption and recycling of materials on Earth potentially reducing costs and increasing industrial competitiveness.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waye, Scot

Power electronics that use high-temperature devices pose a challenge for thermal management. With the devices running at higher temperatures and having a smaller footprint, the heat fluxes increase from previous power electronic designs. This project overview presents an approach to examine and design thermal management strategies through cooling technologies to keep devices within temperature limits, dissipate the heat generated by the devices and protect electrical interconnects and other components for inverter, converter, and charger applications. This analysis, validation, and demonstration intends to take a multi-scale approach over the device, module, and system levels to reduce size, weight, and cost.

Conceptual basis for an integrated system for the management of a protected area. Examples from its application in a mediterranean area.

PubMed

Cornejo, E; Fungairiño, S G; Barandica, J M; Serrano, J M; Zorrilla, J M; Gómez, T; Zapata, F J; Acosta, F J

2016-01-15

Improving the efficiency of management in protected areas is imperative in a generalized context of limited conservation budgets. However, this is overlooked due to flaws in problem definition, general disregard for cost information, and a lack of suitable tools for measuring costs and management quality. This study describes an innovative methodological framework, implemented in the web application SIGEIN, focused on maximizing the quality of management against its costs, establishing an explicit justification for any decision. The tool integrates, with this aim, a procedure for prioritizing management objects according to a conservation value, modified by a functional criterion; a project management module; and a module for management of continuous assessment. This appraisal associates the relevance of the conservation targets, the efficacy of the methods employed, both resource and personnel investments, and the resulting costs. Preliminary results of a prototypical SIGEIN application on the Site of Community Importance Chafarinas Islands are included. Copyright © 2015 Elsevier Ltd. All rights reserved.

Technology advances needed for photovoltaics to achieve widespread grid price parity: Widespread grid price parity for photovoltaics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones-Albertus, Rebecca; Feldman, David; Fu, Ran

2016-04-20

To quantify the potential value of technological advances to the photovoltaics (PV) sector, this paper examines the impact of changes to key PV module and system parameters on the levelized cost of energy (LCOE). The parameters selected include module manufacturing cost, efficiency, degradation rate, and service lifetime. NREL's System Advisor Model (SAM) is used to calculate the lifecycle cost per kilowatt-hour (kWh) for residential, commercial, and utility scale PV systems within the contiguous United States, with a focus on utility scale. Different technological pathways are illustrated that may achieve the Department of Energy's SunShot goal of PV electricity that ismore » at grid price parity with conventional electricity sources. In addition, the impacts on the 2015 baseline LCOE due to changes to each parameter are shown. These results may be used to identify research directions with the greatest potential to impact the cost of PV electricity.« less

Large-area triple-junction a-Si alloy production scaleup. Annual subcontract report, 17 March 1993--18 March 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oswald, R.; Morris, J.

1994-11-01

The objective of this subcontract over its three-year duration is to advance Solarex`s photovoltaic manufacturing technologies, reduce its a-Si:H module production costs, increase module performance and expand the Solarex commercial production capacity. Solarex shall meet these objectives by improving the deposition and quality of the transparent front contact, by optimizing the laser patterning process, scaling-up the semiconductor deposition process, improving the back contact deposition, scaling-up and improving the encapsulation and testing of its a-Si:H modules. In the Phase 2 portion of this subcontract, Solarex focused on improving deposition of the front contact, investigating alternate feed stocks for the front contact,more » maximizing throughput and area utilization for all laser scribes, optimizing a-Si:H deposition equipment to achieve uniform deposition over large-areas, optimizing the triple-junction module fabrication process, evaluating the materials to deposit the rear contact, and optimizing the combination of isolation scribe and encapsulant to pass the wet high potential test. Progress is reported on the following: Front contact development; Laser scribe process development; Amorphous silicon based semiconductor deposition; Rear contact deposition process; Frit/bus/wire/frame; Materials handling; and Environmental test, yield and performance analysis.« less

3D printed Lego®-like modular microfluidic devices based on capillary driving.

PubMed

Nie, Jing; Gao, Qing; Qiu, Jing-Jiang; Sun, Miao; Liu, An; Shao, Lei; Fu, Jian-Zhong; Zhao, Peng; He, Yong

2018-03-12

The field of how to rapidly assemble microfluidics with modular components continuously attracts researchers' attention, however, extra efforts must be devoted to solving the problems of leaking and aligning between individual modules. This paper presents a novel type of modular microfluidic device, driven by capillary force. There is no necessity for a strict seal or special alignment, and its open structures make it easy to integrate various stents and reactants. The key rationale for this method is to print different functional modules with a low-cost three-dimensional (3D) printer, then fill the channels with capillary materials and assemble them with plugs like Lego ® bricks. This rapidly reconstructed modular microfluidic device consists of a variety of common functional modules and other personalized modules, each module having a unified standard interface for easy assembly. As it can be printed by a desktop 3D printer, the manufacturing process is simple and efficient, with controllable regulation of the flow channel scale. Through diverse combinations of different modules, a variety of different functions can be achieved, without duplicating the manufacturing process. A single module can also be taken out for testing and analysis. What's more, combined with basic circuit components, it can serve as a low-cost Lego ® -like modular microfluidic circuits. As a proof of concept, the modular microfluidic device has been successfully demonstrated and used for stent degradation and cell cultures, revealing the potential use of this method in both chemical and biological research.

Optical Metrology for CIGS Solar Cell Manufacturing and its Cost Implications

NASA Astrophysics Data System (ADS)

Sunkoju, Sravan Kumar

Solar energy is a promising source of renewable energy which can meet the demand for clean energy in near future with advances in research in the field of photovoltaics and cost reduction by commercialization. Availability of a non-contact, in-line, real time robust process control strategies can greatly aid in reducing the gap between cell and module efficiencies, thereby leading to cost-effective large-scale manufacturing of high efficiency CIGS solar cells. In order to achieve proper process monitoring and control for the deposition of the functional layers of CuIn1-xGaxSe 2 (CIGS) based thin film solar cell, optical techniques such as spectroscopic reflectometry and polarimetry are advantageous because they can be set up in an unobtrusive manner in the manufacturing line, and collect data in-line and in-situ. The use of these techniques requires accurate optical models that correctly represent the properties of the layers being deposited. In this study, Spectroscopic ellipsometry (SE) has been applied for the characterization of each individual stage of CIGS layers deposited using the 3-stage co-evaporation process along with the other functional layers. Dielectric functions have been determined for the energy range from 0.7 eV to 5.1 eV. Critical-point line-shape analysis was used in this study to determine the critical point energies of the CIGS based layers. To control the compositional and thickness uniformity of all the functional layers during the fabrication of CIGS solar cells over large areas, multilayer photovoltaics (PV) stack optical models were developed with the help of extracted dielectric functions. In this study, mapping capability of RC2 spectroscopic ellipsometer was used to map all the functional layer thicknesses of a CIGS solar cell in order to probe the spatial non-uniformities that can affect the performance of a cell. The optical functions for each of the stages of CIGS 3-stage deposition process along with buffer layer and transparent conducting oxide (TCO) bi-layer, thus derived were used in a fiber optic-based spectroscopic reflectometry optical monitoring system installed in the pilot line at the PVMC's Halfmoon facility. Results obtained from this study show that the use of regular fiber optics, instead of polarization-maintaining fiber optics, is sufficient for the purpose of process monitoring. Also, the technique does not need to be used "in-situ", but the measurements can be taken in-line, and are applicable to a variety of deposition techniques used for different functional layers deposited on rigid or flexible substrates. In addition, effect of Cu concentration on the CIGS optical properties has been studied. Mixed CIGS/Cu2-xSe phase was observed at the surface at the end of the second stage of 3-stage deposition process, under Cu-rich conditions. A significant change in optical behavior of CIGS due to Cu2-xSe at the surface was observed under Cu-rich conditions, which can be used as end-point detection method to move from 2nd stage to 3rd stage in the deposition process. Developed optical functions were applied to in-line reflectance measurements not only to identify the Cu2-xSe phase at the surface but also to measure the thickness of the mixed CIGS/Cu2-xSe layer. This spectroscopic reflectometry based in-line process control technique can be used for end-point detection as well as to control thickness during the preparation of large area CIGS films. These results can assist in the development of optical process-control tools for the manufacturing of high quality CIGS based photovoltaic cells, increasing the uptime and yield of the production line. Finally, to understand the cost implications, low cost potential of two different deposition technologies has been studied on both rigid and flexible substrates with the help of cost analysis. Cost advantages of employing a contactless optics based process control technique have been investigated in order to achieve a low cost of < 0.5 $/W for CIGS module production. Based on cost analysis, one of the best strategies for achieving the low cost targets would be increasing manufacturing throughput, using roll-to-roll thin-film module manufacturing, with co-evaporation and chemical bath deposition processes for absorber and buffer layer respectively, while applying a low-cost process control technique such as spectroscopic reflectometry to improve module efficiencies and maintain high yield.

Thin-film photovoltaic power generation offers decreasing greenhouse gas emissions and increasing environmental co-benefits in the long term.

PubMed

Bergesen, Joseph D; Heath, Garvin A; Gibon, Thomas; Suh, Sangwon

2014-08-19

Thin-film photovoltaic (PV) technologies have improved significantly recently, and similar improvements are projected into the future, warranting reevaluation of the environmental implications of PV to update and inform policy decisions. By conducting a hybrid life cycle assessment using the most recent manufacturing data and technology roadmaps, we compare present and projected environmental, human health, and natural resource implications of electricity generated from two common thin-film PV technologies-copper indium gallium selenide (CIGS) and cadmium telluride (CdTe)-in the United States (U.S.) to those of the current U.S. electricity mix. We evaluate how the impacts of thin films can be reduced by likely cost-reducing technological changes: (1) module efficiency increases, (2) module dematerialization, (3) changes in upstream energy and materials production, and (4) end-of-life recycling of balance of system (BOS). Results show comparable environmental and resource impacts for CdTe and CIGS. Compared to the U.S. electricity mix in 2010, both perform at least 90% better in 7 of 12 and at least 50% better in 3 of 12 impact categories, with comparable land use, and increased metal depletion unless BOS recycling is ensured. Technological changes, particularly efficiency increases, contribute to 35-80% reductions in all impacts by 2030.

Design of smart home gateway based on Wi-Fi and ZigBee

NASA Astrophysics Data System (ADS)

Li, Yang

2018-04-01

With the increasing demand for home lifestyle, the traditional smart home products have been unable to meet the needs of users. Aim at the complex wiring, high cost and difficult operation problems of traditional smart home system, this paper designs a home gateway for smart home system based on Wi-Fi and ZigBee. This paper first gives a smart home system architecture base on cloud server, Wi-Fi and ZigBee. This architecture enables users to access the smart home system remotely from Internet through the cloud server or through Wi-Fi at home. It also offers the flexibility and low cost of ZigBee wireless networking for home equipment. This paper analyzes the functional requirements of the home gateway, and designs a modular hardware architecture based on the RT5350 wireless gateway module and the CC2530 ZigBee coordinator module. Also designs the software of the home gateway, including the gateway master program and the ZigBee coordinator program. Finally, the smart home system and home gateway are tested in two kinds of network environments, internal network and external network. The test results show that the designed home gateway can meet the requirements, support remote and local access, support multi-user, support information security technology, and can timely report equipment status information.

A One ppm NDIR Methane Gas Sensor with Single Frequency Filter Denoising Algorithm

PubMed Central

Zhu, Zipeng; Xu, Yuhui; Jiang, Binqing

2012-01-01

A non-dispersive infrared (NDIR) methane gas sensor prototype has achieved a minimum detection limit of 1 parts per million by volume (ppm). The central idea of the design of the sensor is to decrease the detection limit by increasing the signal to noise ratio (SNR) of the system. In order to decrease the noise level, a single frequency filter algorithm based on fast Fourier transform (FFT) is adopted for signal processing. Through simulation and experiment, it is found that the full width at half maximum (FWHM) of the filter narrows with the extension of sampling period and the increase of lamp modulation frequency, and at some optimum sampling period and modulation frequency, the filtered signal maintains a noise to signal ratio of below 1/10,000. The sensor prototype provides the key techniques for a hand-held methane detector that has a low cost and a high resolution. Such a detector may facilitate the detection of leakage of city natural gas pipelines buried underground, the monitoring of landfill gas, the monitoring of air quality and so on.

Plug cluster engine concept for in-space missions

NASA Technical Reports Server (NTRS)

Obrien, C. J.; Aukerman, C. A.

1979-01-01

The development of a suitable orbital transfer vehicle (OTV) engine is discussed. The OTV's dimensions are limited by those of the Space Shuttle payload bay on which it will be carried. An approach to utilize the available diameter to achieve high area ratio and thus high engine performance, is presented. Unconventional nozzles, such as clusters of small thrusters around a large diameter contoured plug, are investigated to arrive at engine designs which feature lower chamber pressures, with attendant lower heat flux, lower wall temperature, longer fatigue life, and less critical turbomachinery. Attention is also given to plug nozzle technology, high area ratio module- and scarfed bell- Plug Cluster Engine (PCE) concepts, as well as PCE performance, weight, and assessment. A conceptual design of a PCE formed from a cluster of high area ratio, scarfed, bell nozzles proved to be competitive with bell and spike nozzle engines. PCE advantages cited include increased payload length due to shorter engine length, ability to increase or decrease the number of modules and thereby the thrust, and low cost due to utilization of off-the-shelf technology.

Enhanced isoprene biosynthesis in Saccharomyces cerevisiae by engineering of the native acetyl-CoA and mevalonic acid pathways with a push-pull-restrain strategy.

PubMed

Lv, Xiaomei; Xie, Wenping; Lu, Wenqiang; Guo, Fei; Gu, Jiali; Yu, Hongwei; Ye, Lidan

2014-09-30

To explore the capacity of isoprene production in Saccharomyces cerevisiae, a rational push-pull-restrain strategy was proposed to engineer the mevalonic acid (MVA) and acetyl-CoA pathways. The strategy can be decomposed into the up-regulation of precursor supply in the acetyl-CoA module and the MVA pathway (push-strategy), increase of the isoprene branch flux (pull-strategy), and down-regulation of the competing pathway (restrain-strategy). Furthermore, to reduce the production cost arising from galactose addition and meanwhile maintain the high expression of Gal promoters, the galactose regulatory network was modulated by Gal80p deletion. Finally, the engineered strain YXM10-ispS-ispS could accumulate up to 37 mg/L isoprene (about 782-fold increase compared to the parental strain) under aerobic conditions with glycerol-sucrose as carbon source. In this way, a new potential platform for isoprene production was established via metabolic engineering of the yeast native pathways. Copyright © 2014 Elsevier B.V. All rights reserved.

INCREASING EVIDENCE FOR HEMISPHERICAL POWER ASYMMETRY IN THE FIVE-YEAR WMAP DATA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoftuft, J.; Eriksen, H. K.; Hansen, F. K.

Motivated by the recent results of Hansen et al. concerning a noticeable hemispherical power asymmetry in the Wilkinson Microwave Anisotropy Probe (WMAP) data on small angular scales, we revisit the dipole-modulated signal model introduced by Gordon et al.. This model assumes that the true cosmic microwave background signal consists of a Gaussian isotropic random field modulated by a dipole, and is characterized by an overall modulation amplitude, A, and a preferred direction, p-hat. Previous analyses of this model have been restricted to very low resolution (i.e., 3.{sup 0}6 pixels, a smoothing scale of 9 deg. FWHM, and l {approx}< 40)more » due to computational cost. In this paper, we double the angular resolution (i.e., 1.{sup 0}8 pixels and 4.{sup 0}5 FWHM smoothing scale), and compute the full corresponding posterior distribution for the five-year WMAP data. The results from our analysis are the following: the best-fit modulation amplitude for l {<=} 64 and the ILC data with the WMAP KQ85 sky cut is A = 0.072 {+-} 0.022, nonzero at 3.3{sigma}, and the preferred direction points toward Galactic coordinates (l, b) = (224 deg., - 22 deg.) {+-} 24 deg. The corresponding results for l {approx}< 40 from earlier analyses were A = 0.11 {+-} 0.04 and (l, b) = (225 deg. - 27 deg.). The statistical significance of a nonzero amplitude thus increases from 2.8{sigma} to 3.3{sigma} when increasing l{sub max} from 40 to 64, and all results are consistent to within 1{sigma}. Similarly, the Bayesian log-evidence difference with respect to the isotropic model increases from {delta}ln E = 1.8 to {delta}ln E = 2.6, ranking as 'strong evidence' on the Jeffreys' scale. The raw best-fit log-likelihood difference increases from {delta}ln L = 6.1 to {delta}ln L = 7.3. Similar, and often slightly stronger, results are found for other data combinations. Thus, we find that the evidence for a dipole power distribution in the WMAP data increases with l in the five-year WMAP data set, in agreement with the reports of Hansen et al.« less

Cool covered sky-splitting spectrum-splitting FK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohedano, Rubén; Chaves, Julio; Falicoff, Waqidi

2014-09-26

Placing a plane mirror between the primary lens and the receiver in a Fresnel Köhler (FK) concentrator gives birth to a quite different CPV system where all the high-tech components sit on a common plane, that of the primary lens panels. The idea enables not only a thinner device (a half of the original) but also a low cost 1-step manufacturing process for the optics, automatic alignment of primary and secondary lenses, and cell/wiring protection. The concept is also compatible with two different techniques to increase the module efficiency: spectrum splitting between a 3J and a BPC Silicon cell formore » better usage of Direct Normal Irradiance DNI, and sky splitting to harvest the energy of the diffuse radiation and higher energy production throughout the year. Simple calculations forecast the module would convert 45% of the DNI into electricity.« less

PRESAGE® as a solid 3-D radiation dosimeter: A review article

NASA Astrophysics Data System (ADS)

Khezerloo, Davood; Nedaie, Hassan Ali; Takavar, Abbas; Zirak, Alireza; Farhood, Bagher; Movahedinejhad, Hadi; Banaee, Nooshin; Ahmadalidokht, Isa; Knuap, Courtney

2017-12-01

Radiation oncology has been rapidly improved by the application of new equipment and techniques. With the advent of new complex and precise radiotherapy techniques such as intensity modulated radiotherapy, stereotactic radiosurgery, and volumetric modulated arc therapy, the demand for an accurate and feasible three-dimensional (3-D) dosimetry system has increased. The most important features of a 3-D dosimeter, apart from being precise, accurate and reproducible, include also its low cost, feasibility, and availability. In 2004 a new generation of solid plastic dosimeters which demonstrate a radiochromic response to ionizing radiation was introduced. PRESAGE® plastic dosimeter lacks the limitations of previous Ferric and polymer plastic 3-D dosimeters such as diffusion, sensitivity to oxygen, fabrication problems, scanning and read out challenges. In this decade, a large number of efforts have been carried out to enhance PRESAGE® structure and scanning methods. This article attempts to review and reflect on the results of these investigations.

Enhanced Impurity-Free Intermixing Bandgap Engineering for InP-Based Photonic Integrated Circuits

NASA Astrophysics Data System (ADS)

Cui, Xiao; Zhang, Can; Liang, Song; Zhu, Hong-Liang; Hou, Lian-Ping

2014-04-01

Impurity-free intermixing of InGaAsP multiple quantum wells (MQW) using sputtering Cu/SiO2 layers followed by rapid thermal processing (RTP) is demonstrated. The bandgap energy could be modulated by varying the sputtering power and time of Cu, RTP temperature and time to satisfy the demands for lasers, modulators, photodetector, and passive waveguides for the photonic integrated circuits with a simple procedure. The blueshift of the bandgap wavelength of MQW is experimentally investigated on different sputtering and annealing conditions. It is obvious that the introduction of the Cu layer could increase the blueshift more greatly than the common impurity free vacancy disordering technique. A maximum bandgap blueshift of 172 nm is realized with an annealing condition of 750°C and 200s. The improved technique is promising for the fabrication of the active/passive optoelectronic components on a single wafer with simple process and low cost.

Porous Silicon as Antireflecting Layer

NASA Astrophysics Data System (ADS)

Kosoglu, Gulsen; Yumak, Mehmet; Okmen, Selim; Ozatay, Ozhan; Skarlatos, Yani; Garcia, Carlos

2013-03-01

The main aim in photovoltaic industry is to produce efficient and energy competitive solar cell modules at low cost. Efficient AntiReflection Coatings (ARC) improve light collection and thereby increase the current output of solar cells. Broadband ARCs are desirable for efficient application over the entire solar spectrum and porous silicon layers as antireflective coating layers provide successful light collection. In the study the most critical physical parameters of porous silicon are examined, homogeneous and uniform porous layers are produced. The photoluminescence spectrum and optical parameters of porous layers have been investigated, and we are now in the process of improving the efficiency of the device by modulating the structure of the porous silicon layers and studying its photovoltaic characteristics. We would like to thank to Mr. Aziz U. Caliskan and his group for their valuable support from TUBITAK YITAL. This Project is supported by Bogazici University Research Funding: 5782, TUBITAK Grant : 209T099, and Bogazici University Infrared Funding: 6121.

An integrated open-cavity system for magnetic bead manipulation.

PubMed

Abu-Nimeh, F T; Salem, F M

2013-02-01

Superparamagnetic beads are increasingly used in biomedical assays to manipulate, transport, and maneuver biomaterials. We present a low-cost integrated system designed in bulk CMOS to manipulate and separate biomedical magnetic beads. The system consists of 8 × 8 coil-arrays suitable for single bead manipulation, or collaborative multi-bead manipulation, using pseudo-parallel executions. We demonstrate the flexibility of the design in terms of different coil sizes, DC current levels, and layout techniques. In one array module example, the size of a single coil is 30 μm × 30 μm and the full array occupies an area of 248 μm × 248 μm in 0.5 μm CMOS technology. The programmable DC current source supports 8 discrete levels up to 1.5 mA. The total power consumption of the entire module is 9 mW when running at full power.

1.55 µm high speed low chirp electroabsorption modulated laser arrays based on SAG scheme.

PubMed

Cheng, Yuanbing; Wang, Qi Jie; Pan, Jiaoqing

2014-12-15

We demonstrate a cost-effective 1.55 µm low chirp 4 × 25 Gbit/s electroabsorption modulated laser (EML) array with 0.8 nm channel spacing by varying ridge width of the lasers and using selective area growth (SAG) integration scheme. The devices for all the 4 channels within the EML array show uniform threshold currents around 18 mA and high SMSRs over 45 dB. The output optical power of each channel is about 9 mW at an injection current of 100 mA. The typical chirp value of single EML measured by a fiber resonance method varied from 2.2 to -4 as the bias voltage was increased from 0 V to 2.5 V. These results show that the EML array is a suitable light source for 100 Gbit/s optical transmissions.

Hybrid GMR Sensor Detecting 950 pT/sqrt(Hz) at 1 Hz and Room Temperature

PubMed Central

Guedes, André; Macedo, Rita; Jaramillo, Gerardo; Freitas, Paulo P.; Horsley, David A.

2018-01-01

Advances in the magnetic sensing technology have been driven by the increasing demand for the capability of measuring ultrasensitive magnetic fields. Among other emerging applications, the detection of magnetic fields in the picotesla range is crucial for biomedical applications. In this work Picosense reports a millimeter-scale, low-power hybrid magnetoresistive-piezoelectric magnetometer with subnanotesla sensitivity at low frequency. Through an innovative noise-cancelation mechanism, the 1/f noise in the MR sensors is surpassed by the mechanical modulation of the external magnetic fields in the high frequency regime. A modulation efficiency of 13% was obtained enabling a final device’s sensitivity of ~950 pT/Hz1/2 at 1 Hz. This hybrid device proved to be capable of measuring biomagnetic signals generated in the heart in an unshielded environment. This result paves the way for the development of a portable, contactless, low-cost and low-power magnetocardiography device. PMID:29509677

Space Station

NASA Image and Video Library

1986-08-01

In response to President Reagan's directive to NASA to develop a permanent marned Space Station within a decade, part of the State of the Union message to Congress on January 25, 1984, NASA and the Administration adopted a phased approach to Station development. This approach provided an initial capability at reduced costs, to be followed by an enhanced Space Station capability in the future. This illustration depicts a configuration with enhanced capabilities. It builds on the horizontal boom and module pattern of the revised baseline. This configuration would feature dual keels, two vertical spines 105-meters long joined by upper and lower booms. The structure carrying the modules would become a transverse boom of a basically rectangular structure. The two new booms, 45-meters in length, would provide extensive accommodations for attached payloads, and would offer a wide field of view. Power would be increased significantly, with the addition if a 50-kW solar dynamic power system.

Socio-ecological transitions trigger fire regime shifts and modulate fire-climate interactions in the Sierra Nevada, CA, 1600-2015 CE

NASA Astrophysics Data System (ADS)

Trouet, V.; Taylor, A. H.; Skinner, C. N.; Stephens, S.

2016-12-01

In California, large wildfires cause significant socio-ecological impacts and they incur high federal funding costs for fire suppression. Future fire activity is projected to increase with climate change, but anthropogenic effects can modulate or even override climatic effects causing large uncertainty in fire projections. We developed a 415-year fire history record (1600-2015 CE) based on tree-ring fire-scar data from 29 sites throughout the Sierra Nevada, California. Changes in socio-ecological systems from the Native American to the current period drove large historical fire regime shifts in our record and socio-ecological conditions amplified and buffered fire response to climate. Fire activity was highest and fire-climate relationships were strongest after Native American depopulation - following mission establishment ca. 1775 CE - reduced the self-limiting effect of Native American burns on fire spread. With the Gold Rush and Euro-American immigration (ca. 1865 CE), area burned declined and the strong multidecadal relationship between temperature and fire decayed and then disappeared after implementation of fire suppression (ca. 1900 CE). The past anthropogenic modulation of fire-climate relationships underscores the need for nuanced representations of human-fire interactions to improve the skill of future fire-climate projections. In California, large wildfires cause significant socio-ecological impacts and they incur high federal funding costs for fire suppression. Future fire activity is projected to increase with climate change, but anthropogenic effects can modulate or even override climatic effects causing large uncertainty in fire projections. We developed a 415-year fire history record (1600-2015 CE) based on tree-ring fire-scar data from 29 sites throughout the Sierra Nevada, California. Changes in socio-ecological systems from the Native American to the current period drove large historical fire regime shifts in our record and socio-ecological conditions amplified and buffered fire response to climate. Fire activity was highest and fire-climate relationships were strongest after Native American depopulation - following mission establishment ca. 1775 CE - reduced the self-limiting effect of Native American burns on fire spread. With the Gold Rush and Euro-American immigration (ca. 1865 CE), area burned declined and the strong multidecadal relationship between temperature and fire decayed and then disappeared after implementation of fire suppression (ca. 1900 CE). The past anthropogenic modulation of fire-climate relationships underscores the need for nuanced representations of human-fire interactions to improve the skill of future fire-climate projections.

The Air Force Manufacturing Technology (MANTECH): Technology transfer methodology as exemplified by the radar transmit/receive module program

NASA Technical Reports Server (NTRS)

Houpt, Tracy; Ridgely, Margaret

1991-01-01

The Air Force Manufacturing Technology program is involved with the improvement of radar transmit/receive modules for use in active phased array radars for advanced fighter aircraft. Improvements in all areas of manufacture and test of these modules resulting in order of magnitude improvements in the cost of and the rate of production are addressed, as well as the ongoing transfer of this technology to the Navy.

Design and Performance of a Miniature Radar L-Band Transceiver

NASA Technical Reports Server (NTRS)

McWatters, D.; Price, D.; Edelstein, W.

2004-01-01

Radar electronics developed for past JPL space missions historically had been custom designed and as such, given budgetary, time, and risk constraints, had not been optimized for maximum flexibility or miniaturization. To help reduce cost and risk of future radar missions, a generic radar module was conceived. The module includes a 1.25-GHz (L-band) transceiver and incorporates miniature high-density packaging of integrated circuits in die/chip form. The technology challenges include overcoming the effect of miniaturization and high packaging density to achieve the performance, reliability, and environmental ruggedness required for space missions. The module was chosen to have representative (generic) functionality most likely required from an L-band radar. For very large aperture phased-array spaceborne radar missions, the large dimensions of the array suggest the benefit of distributing the radar electronics into the antenna array. For such applications, this technology is essential in order to bring down the cost, mass, and power of the radar electronics module replicated in each panel of the array. For smaller sized arrays, a single module can be combined with the central radar controller and still provide the bene.ts of configuration .exibility, low power, and low mass. We present the design approach for the radar electronics module and the test results for its radio frequency (RF) portion: a miniature, low-power, radiation-hard L-band transceiver.

Activation of cannabinoid system in anterior cingulate cortex and orbitofrontal cortex modulates cost-benefit decision making.

PubMed

Khani, Abbas; Kermani, Mojtaba; Hesam, Soghra; Haghparast, Abbas; Argandoña, Enrike G; Rainer, Gregor

2015-06-01

Despite the evidence for altered decision making in cannabis abusers, the role of the cannabinoid system in decision-making circuits has not been studied. Here, we examined the effects of cannabinoid modulation during cost-benefit decision making in the anterior cingulate cortex (ACC) and orbitofrontal cortex (OFC), key brain areas involved in decision making. We trained different groups of rats in a delay-based and an effort-based form of cost-benefit T-maze decision-making task. During test days, the rats received local injections of either vehicle or ACEA, a cannabinoid type-1 receptor (CB1R) agonist in the ACC or OFC. We measured spontaneous locomotor activity following the same treatments and characterized CB1Rs localization on different neuronal populations within these regions using immunohistochemistry. We showed that CB1R activation in the ACC impaired decision making such that rats were less willing to invest physical effort to gain high reward. Similarly, CB1R activation in the OFC induced impulsive pattern of choice such that rats preferred small immediate rewards to large delayed rewards. Control tasks ensured that the effects were specific for differential cost-benefit tasks. Furthermore, we characterized widespread colocalizations of CB1Rs on GABAergic axonal ends but few colocalizations on glutamatergic, dopaminergic, and serotonergic neuronal ends. These results provide first direct evidence that the cannabinoid system plays a critical role in regulating cost-benefit decision making in the ACC and OFC and implicate cannabinoid modulation of synaptic ends of predominantly interneurons and to a lesser degree other neuronal populations in these two frontal regions.

Investigation of test methods, material properties, and processes for solar cell encapsulants

NASA Technical Reports Server (NTRS)

Willis, P. B.

1981-01-01

Encapsulant materials and processes for the production of cost-effective, long-life solar cell modules were investigated. The following areas were explored: (1) soil resistant surface treatment; (2) corrosion protecting coatings from mild steel substrates; (3) primers for bonding module interfaces; and (4) RS/4 accelerated aging of candidate encapsulation compounds