Science.gov

Sample records for control technical exchange

  1. Cox report and the US-China arms control technical exchange program

    SciTech Connect

    Di Capua, M S

    1999-09-01

    The ACE program furthered the national security interests of the US by promoting technical approaches to the implementation and verification of arms control treaties that the international community embraces. The Cox Committee report suggests that uncontrolled interactions were taking place between US and Chinese nuclear weapons scientists in the course of the ACE program. On the contrary, elaborate controls were in place at the very beginning and remained in place to control the interactions and protect US national security information. The ACE program payoff to national security was just beginning and its suspension, resulting from the Cox reports allegations, is a setback to US-China progress on arms control.

  2. Microtube strip heat exchanger. Final technical report

    SciTech Connect

    Doty, F.D.

    1992-07-09

    The purpose of this contract has been to explore the limits of miniaturization of heat exchangers with the goals of (1) improving the theoretical understanding of laminar heat exchangers, (2) evaluating various manufacturing difficulties, and (3) identifying major applications for the technology. A low-cost, ultra-compact heat exchanger could have an enormous impact on industry in the areas of cryocoolers and energy conversion. Compact cryocoolers based on the reverse Brayton cycle (RBC) would become practical with the availability of compact heat exchangers. Many experts believe that hardware advances in personal computer technology will rapidly slow down in four to six years unless lowcost, portable cryocoolers suitable for the desktop supercomputer can be developed. Compact refrigeration systems would permit dramatic advances in high-performance computer work stations with ``conventional`` microprocessors operating at 150 K, and especially with low-cost cryocoolers below 77 K. NASA has also expressed strong interest in our MTS exchanger for space-based RBC cryocoolers for sensor cooling. We have demonstrated feasibility of higher specific conductance by a factor of five than any other work in high-temperature gas-to-gas exchangers. These laminar-flow, microtube exchangers exhibit extremely low pressure drop compared to alternative compact designs under similar conditions because of their much shorter flow length and larger total flow area for lower flow velocities. The design appears to be amenable to mass production techniques, but considerable process development remains. The reduction in materials usage and the improved heat exchanger performance promise to be of enormous significance in advanced engine designs and in cryogenics.

  3. 2011 PERFORMANCE ASSESSMENT COMMUNITY OF PRACTICE TECHNICAL EXCHANGE - SUMMARY

    SciTech Connect

    Seitz, R.

    2011-12-30

    The Performance Assessment Community of Practice (PA CoP) was developed in 2008 to improve consistency and quality in the preparation of performance assessments (PAs) and risk assessments across the Department of Energy (DOE) Complex. The term, PA, is used to represent all of these modeling applications in this report. The PA CoP goals are to foster the exchange of information among PA practitioners and to share lessons learned from PAs conducted for DOE, commercial disposal facilities, and international entities. Technical exchanges and workshops are a cornerstone of PA CoP activities. Previous technical exchanges have addressed Engineered Barriers (2009 - http://www.cresp.org/education/workshops/pacop/), the Advanced Simulation Capability for Environmental Management and the Cementitious Barriers Partnership (2010 - http://srnl.doe.gov/copexchange/links.htm). Each technical exchange also includes summary presentations regarding activities at DOE, the Nuclear Regulatory Commission (NRC) and other organizations (e.g., International Atomic Energy Agency (IAEA)) as well as a number of presentations from selected sites to provide insight and perspective from on-going modeling activities. Through the deployment of PA Assistance Teams, the PA CoP has also been engaged in the development of new PAs across the DOE Complex. As a way of improving consistency in the preparation of new PAs, the teams provide technical advice and share experiences, noteworthy practices, and lessons learned from previous Low-Level Waste Disposal Facility Federal Review Group (LFRG) reviews. Teams have provided support for PAs at Hanford, Idaho, Paducah and Portsmouth. The third annual PA CoP Technical Exchange was held on May 25-26, 2011 in Atlanta, GA. The PA CoP Steering Committee Meeting held its first meeting on May 24 prior to the Technical Exchange. Decision making using models and software quality assurance were the topical emphasis for the exchange. A new feature at the 2011 technical

  4. Technical Note: A minimally invasive experimental system for pCO2 manipulation in plankton cultures using passive gas exchange (atmospheric carbon control simulator)

    NASA Astrophysics Data System (ADS)

    Love, Brooke A.; Olson, M. Brady; Wuori, Tristen

    2017-05-01

    As research into the biotic effects of ocean acidification has increased, the methods for simulating these environmental changes in the laboratory have multiplied. Here we describe the atmospheric carbon control simulator (ACCS) for the maintenance of plankton under controlled pCO2 conditions, designed for species sensitive to the physical disturbance introduced by the bubbling of cultures and for studies involving trophic interaction. The system consists of gas mixing and equilibration components coupled with large-volume atmospheric simulation chambers. These chambers allow gas exchange to counteract the changes in carbonate chemistry induced by the metabolic activity of the organisms. The system is relatively low cost, very flexible, and when used in conjunction with semi-continuous culture methods, it increases the density of organisms kept under realistic conditions, increases the allowable time interval between dilutions, and/or decreases the metabolically driven change in carbonate chemistry during these intervals. It accommodates a large number of culture vessels, which facilitate multi-trophic level studies and allow the tracking of variable responses within and across plankton populations to ocean acidification. It also includes components that increase the reliability of gas mixing systems using mass flow controllers.

  5. The Electrically Controlled Exchange Bias

    NASA Astrophysics Data System (ADS)

    Harper, Jacob

    Controlling magnetism via voltage in the virtual absence of electric current is the key to reduce power consumption while enhancing processing speed, integration density and functionality in comparison with present-day information technology. Almost all spintronic devices rely on tailored interface magnetism. Controlling magnetism at thin-film interfaces, preferably by purely electrical means, is therefore a key challenge to better spintronics. However, there is no direct interaction between magnetization and electric fields, thus making voltage control of magnetism in general a scientific challenge. The significance of controlled interface magnetism started with the exchange-bias effect. Exchange bias is a coupling phenomenon at magnetic interfaces that manifests itself prominently in the shift of the ferromagnetic hysteresis loop along the magnetic-field axis. Various attempts on controlling exchange bias via voltage utilizing different scientific principles have been intensively studied recently. The majority of present research is emphasizing on various complex oxides. Our approach can be considered as a paradigm shift away from complex oxides. We focus on a magnetoelectric antiferromagnetic simple oxide Cr2O3. From a combination of experimental and theoretical efforts, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias between positive and negative values by reversing the electric field while maintaining a permanent magnetic field. This is a significant scientific breakthrough providing a new route towards potentially revolutionizing information technology. In addition, a second path of electrically controlled exchange bias is introduced by exploiting the piezoelectric property of BaTiO3. An exchange-bias Co

  6. United States: Ukraine Technical Exchange II trip report

    SciTech Connect

    Moak, D.J.; Wendling, M.A.

    1995-02-01

    May 15--21, 1994, the first technical conference was held at Hanford between Ukraine-Chornobyl, Westinghouse Hanford, and SAIC, to exchange technical information and experience gained in cleanup and stabilization of radioactive contamination at Hanford and Chornobyl. Protocol was signed for a second exchange and technology demonstration program in Kiev and near Chornobyl power plants. Technical Exchange No. 2 was held from August 28--September 9, 1994, with 3 focus areas: field demonstration of DOE-Hanford technologies and application to cleanup of contaminated lands resulting from 1986 Chornobyl accident; application of other US DOE-technologies; and observation/evaluation of Ukraine-developed technologies for potential application in USA. Three radiological mapping systems were demonstrated near Chornobyl: man-carried Ultrasonic Ranging and Data System, a mobile radiological data system, and NOMAD field gamma spectroscopy system. The Ukraine-Chornobyl team hosted technical presentations, discussions and field trips for 4.5 days, providing insight on the Chornobyl problem and allowing the US team to present overviews on DOE technologies that may be applicable to the Chornobyl situation. It is concluded that Ukrainian scientists have tremendous talent and expended considerable energy in attempting to tackle such a problem, but economic and cultural conditions with Ukraine have prevented them from acquiring the resources to implement basic aspects of characterization and remediation activities. Most of their publications are in Russian only. Their translation, plus resources to carry out proposals for bench scale and field demonstration projects, could benefit the DOE complex and other nuclear programs. The considerable cultural and economic change occurring in Ukraine, is providing opportunities for private industries to assist in the changes and for DOE, others to apply cleanup technologies, and it is essential that close institutional relations be established.

  7. Electric control of exchange bias training.

    PubMed

    Echtenkamp, W; Binek, Ch

    2013-11-01

    Voltage-controlled exchange bias training and tunability are introduced. Isothermal voltage pulses are used to reverse the antiferromagnetic order parameter of magnetoelectric Cr(2)O(3), and thus continuously tune the exchange bias of an adjacent CoPd film. Voltage-controlled exchange bias training is initialized by tuning the antiferromagnetic interface into a nonequilibrium state incommensurate with the underlying bulk. Interpretation of these hitherto unreported effects contributes to new understanding in electrically controlled magnetism.

  8. Electric Control of Exchange Bias Training

    NASA Astrophysics Data System (ADS)

    Echtenkamp, W.; Binek, Ch.

    2013-11-01

    Voltage-controlled exchange bias training and tunability are introduced. Isothermal voltage pulses are used to reverse the antiferromagnetic order parameter of magnetoelectric Cr2O3, and thus continuously tune the exchange bias of an adjacent CoPd film. Voltage-controlled exchange bias training is initialized by tuning the antiferromagnetic interface into a nonequilibrium state incommensurate with the underlying bulk. Interpretation of these hitherto unreported effects contributes to new understanding in electrically controlled magnetism.

  9. Full Electric Control of Exchange Bias

    NASA Astrophysics Data System (ADS)

    Wu, S. M.; Cybart, Shane A.; Yi, D.; Parker, James M.; Ramesh, R.; Dynes, R. C.

    2013-02-01

    We report the creation of a multiferroic field effect device with a BiFeO3 (BFO) (antiferromagnetic-ferroelectric) gate dielectric and a La0.7Sr0.3MnO3 (LSMO) (ferromagnetic) conducting channel that exhibits direct, bipolar electrical control of exchange bias. We show that exchange bias is reversibly switched between two stable states with opposite exchange bias polarities upon ferroelectric poling of the BFO. No field cooling, temperature cycling, or additional applied magnetic or electric field beyond the initial BFO polarization is needed for this bipolar modulation effect. Based on these results and the current understanding of exchange bias, we propose a model to explain the control of exchange bias. In this model the coupled antiferromagnetic-ferroelectric order in BFO along with the modulation of interfacial exchange interactions due to ionic displacement of Fe3+ in BFO relative to Mn3+/4+ in LSMO cause bipolar modulation.

  10. TECHNICAL COMPARISON OF CANDIDATE ION EXCHANGE MEDIA FOR SMALL COLUMN ION EXCHANGE (SCIX) APPLICATIONS IN SUPPORT OF SUPPLEMENTAL LAW PRETREATMENT

    SciTech Connect

    RAMSEY AA; THORSON MR

    2010-12-28

    At-tank supplemental pretreatment including both filtration and small column ion exchange is currently under evaluation to facilitate salt waste retrieval and processing in the Hanford tank farms. Spherical resorcinol formaldehyde (sRF) resin is the baseline ion exchange resin for use in the Waste Treatment and Immobilization Plant (WTP). This document provides background and technical rationale to assist in determining whether spherical resorcinol formaldehyde (sRF) is also the appropriate ion exchange resin for supplemental LAW pretreatment processes and compares sRF with crystalline silicotitanate (CST) as potential supplemental pretreatment ion exchange media.

  11. Introducing Realism into the Technical Definition Assignment (Exercise Exchange).

    ERIC Educational Resources Information Center

    Curry, Jerome

    1989-01-01

    Describes a writing exercise to help technical writing students determine the appropriate methods of extension for technical definitions, decide which terms need to be defined for a particular audience, and place definitions effectively in the document. (MM)

  12. NASA's experience in the international exchange of scientific and technical information in the aerospace field

    NASA Technical Reports Server (NTRS)

    Thibideau, Philip A.

    1990-01-01

    The early NASA international scientific and technical information exchange arrangements were usually detailed in correspondence with the librarians of the institutions involved. While this type of exchange grew to include some 200 organizations in 43 countries, NASA's main focus shifted to the relationship with the European Space Agency (ESA), which began in 1964. The NASA/ESA Tripartite Exchange Program provides more than 4000 technical reports from the NASA-produced Aerospace Database. The experience in the evolving cooperation between NASA and ESA has established the model for more recent exchange agreements with Israel, Australia, and Canada. The results of these agreements are made available to participating European organizations through the NASA File.

  13. Electrically controlled cesium ion exchange

    SciTech Connect

    Lilga, M.

    1996-10-01

    Several sites within the DOE complex (Savannah River, Idaho, Oak Ridge and Hanford) have underground storage tanks containing high-level waste resulting from nuclear engineering activities. To facilitate final disposal of the tank waste, it is advantageous to separate and concentrate the radionuclides for final immobilization in a vitrified glass matrix. This task proposes a new approach for radionuclide separation by combining ion exchange (IX) and electrochemistry to provide a selective and economic separation method.

  14. Optimal Corrosion Control Treatment Evaluation Technical Recommendations

    EPA Pesticide Factsheets

    This document provides technical recommendations that both systems and primacy agencies can use to comply with LCR CCT requirements and effective evaluation and designation of optimal corrosion control treatment (OCCT).

  15. The International Association for the Exchange of Students for Technical Experience. 34th Annual Report 1981.

    ERIC Educational Resources Information Center

    International Association for the Exchange of Students for Technical Experience/United States, Columbia, MD.

    The 1981 annual report of the International Association for the Exchange of Students for Technical Experience (IAESTE) is presented. IAESTE seeks to provide students at institutions of higher education with technical experience abroad relative to their studies and to promote international understanding among all students. An international report…

  16. The International Association for the Exchange of Students for Technical Experience. 34th Annual Report 1981.

    ERIC Educational Resources Information Center

    International Association for the Exchange of Students for Technical Experience/United States, Columbia, MD.

    The 1981 annual report of the International Association for the Exchange of Students for Technical Experience (IAESTE) is presented. IAESTE seeks to provide students at institutions of higher education with technical experience abroad relative to their studies and to promote international understanding among all students. An international report…

  17. Full Electric Field Control of Exchange Bias

    NASA Astrophysics Data System (ADS)

    Wu, Stephen

    2014-03-01

    Exchange bias is the shift of a magnetic hysteresis curve due to interfacial magnetic coupling between a ferromagnet (FM) and an antiferromagnet (AFM). This ubiquitous effect has long been used in the electronics industry to bias the magnetization of FM layers in magnetic devices. Its continued understanding is of critical importance to advance the development of future high-density magnetic storage media and other novel magnetic devices. However, due to the technological limitations of manipulating and observing an atomically thin interface, exchange bias is not well understood. In this talk we present a multiferroic field effect device with BiFeO3 (BFO) (antiferromagnetic-ferroelectric) as the gate dielectric and La0.7Sr0.3MnO3 (LSMO) (ferromagnetic) as the conducting channel, which exhibits the direct, bipolar electric control of exchange bias. Here the magnetic states at the AFM/FM interface can be directly manipulated with electric fields and the results can be observed as a change in exchange bias polarity and magnitude. Control of exchange bias at this level has significant implications because it represents a form of electric field control of magnetism and may potentially offer a route toward the eventual full electric field control of magnetization. In this device, exchange bias is reversibly switched between two stable states with opposite exchange bias polarities upon ferroelectric poling of the BFO. No field cooling, temperature cycling, or additional applied magnetic or electric field beyond BFO poling is needed for this bipolar modulation effect. Detailed temperature dependent measurements and a model will be presented which will attribute this effect to the coupled antiferromagnetic-ferroelectric order in BFO along with the modulation of interfacial exchange interactions due to ionic displacement of Fe3+ in BFO relative to Mn3 + / 4 + in LSMO.

  18. Pulling back the covers: technical lessons of a real-world health information exchange.

    PubMed

    Zafar, Atif; Dixon, Brian E

    2007-01-01

    Several nations and local communities are striving to achieve widespread, secure exchange of clinical data between various health care providers and public health organizations. Most of the literature on health information exchange focuses on the financial, political, and privacy aspects of these initiatives. Perhaps just as important are the technical and organizational factors that have influenced development of data exchange methods and results. One mature network in the Midwestern United States has had success in establishing consistent, secure exchange of clinical data for more than ten years. Presented here are the technical lessons learned and design decisions made from this initiative with the hope that they can be used by others striving to connect disparate clinical information systems for the improvement of health care quality and safety.

  19. Efficient separations and processing crosscutting program 1996 technical exchange meeting. Proceedings

    SciTech Connect

    1996-02-01

    This document contains summaries of technology development presented at the 1996 Efficient Separations and Processing Crosscutting Program Technical Exchange Meeting. This meeting is held annually to promote a free exchange of ideas among technology developers, potential users and other interested parties within the EM community. During this meeting the following many separation processes technologies were discussed such as ion exchange, membrane separation, vacuum distillation, selective sorption, and solvent extraction. Other topics discussed include: waste forms; testing or inorganic sorbents for radionuclide and heavy metal removal; selective crystallization; and electrochemical treatment of liquid wastes. This is the leading abstract, individual papers have been indexed separately for the databases.

  20. Proceedings of the Efficient Separations and Processing Cross-Cutting Program Annual Technical Exchange Meeting

    SciTech Connect

    1995-02-01

    This document contains summaries of technology development presented at the 1995 Efficient Separations and Processing Cross-Cutting Program (ESP) Annual Technical Exchange Meeting. The ESP is sponsored by the US Department of Energy`s Office of Environmental Management (EM), Office of Technology Development. The meeting is held annually to promote a free exchange of ideas among technology developers, potential users (for example, EM focus areas), and other interested parties within EM. During this meeting, developers of ESP-funded technologies describe the problems and needs addressed by their technologies; the technical approach, accomplishments, and resolution of issues; the strategy and schedule for commercialization; and evolving potential applications. Presenters are asked to address the following areas: Target waste management problem, waste stream, or data need; scientific background and technical approach; technical accomplishments and resolution of technical issues; schedule and strategy for commercializing and implementing the technology or acquiring needed data; potential alternate applications of the technology or data, including outside of DOE/EM. The meeting is not a program review of the individual tasks or subtasks; but instead focuses on the technical aspects and implementation of ESP-sponsored technology or data. The meeting is also attended by members of the ESP Technical Review Team, who have the opportunity at that time to review the ESP as a whole.

  1. Prefabricated heat-exchanging fireplace. Final technical report

    SciTech Connect

    Schleper, M.A.

    1981-06-15

    A heat-exchanging fireplace was installed in a 2000 square foot home and the standard air distribution equipment was ducted directly to the forced-air heating system of the home. The standard air distribution equipment for the fireplace included two squirrel-cage blowers which were connected to a thermostat, allowing a choice of temperature ranges; and a snap disc thermostat was used to disconnect the blowers in order to avoid blowing cold air after the fire died out. Arranged in this manner, one is able to set the regular home thermostat a few degrees lower than the fireplace thermostat, and this will allow the regular heating system to turn on after the fire has gone out in the fireplace. Energy consumption in both the fireplace and the conventional heating system was monitored throughout a heating season and then compared with past heating seasons when only a conventional heating system was used.

  2. Technical Data Exchange Software Tools Adapted to Distributed Microsatellite Design

    NASA Astrophysics Data System (ADS)

    Pache, Charly

    2002-01-01

    One critical issue concerning distributed design of satellites, is the collaborative work it requires. In particular, the exchange of data between each group responsible for each subsystem can be complex and very time-consuming. The goal of this paper is to present a design collaborative tool, the SSETI Design Model (SDM), specifically developed for enabling satellite distributed design. SDM is actually used in the ongoing Student Space Exploration &Technology (SSETI) initiative (www.sseti.net). SSETI is lead by European Space Agency (ESA) outreach office (http://www.estec.esa.nl/outreach), involving student groups from all over Europe for design, construction and launch of a microsatellite. The first part of this paper presents the current version of the SDM tool, a collection of Microsoft Excel linked worksheets, one for each subsystem. An overview of the project framework/structure is given, explaining the different actors, the flows between them, as well as the different types of data and the links - formulas - between data sets. Unified Modeling Language (UML) diagrams give an overview of the different parts . Then the SDM's functionalities, developed in VBA scripts (Visual Basic for Application), are introduced, as well as the interactive features, user interfaces and administration tools. The second part discusses the capabilities and limitations of SDM current version. Taking into account these capabilities and limitations, the third part outlines the next version of SDM, a web-oriented, database-driven evolution of the current version. This new approach will enable real-time data exchange and processing between the different actors of the mission. Comprehensive UML diagrams will guide the audience through the entire modeling process of such a system. Tradeoffs simulation capabilities, security, reliability, hardware and software issues will also be thoroughly discussed.

  3. The International Association for the Exchange of Students for Technical Experience. 32nd Annual Report 1979.

    ERIC Educational Resources Information Center

    International Association for the Exchange of Students for Technical Experience/United States, Columbia, MD.

    After a general outline of the organization of the International Association for the Exchange of Students for Technical Experience and a brief introduction to its functions and activities, this annual report contains the international report. This includes: the report of the General Secretary; a list of international visits and visitors; publicity…

  4. The International Association for the Exchange of Students for Technical Experience. 32nd Annual Report 1979.

    ERIC Educational Resources Information Center

    International Association for the Exchange of Students for Technical Experience/United States, Columbia, MD.

    After a general outline of the organization of the International Association for the Exchange of Students for Technical Experience and a brief introduction to its functions and activities, this annual report contains the international report. This includes: the report of the General Secretary; a list of international visits and visitors; publicity…

  5. Distributed control using linear momentum exchange devices

    NASA Technical Reports Server (NTRS)

    Sharkey, J. P.; Waites, Henry; Doane, G. B., III

    1987-01-01

    MSFC has successfully employed the use of the Vibrational Control of Space Structures (VCOSS) Linear Momentum Exchange Devices (LMEDs), which was an outgrowth of the Air Force Wright Aeronautical Laboratory (AFWAL) program, in a distributed control experiment. The control experiment was conducted in MSFC's Ground Facility for Large Space Structures Control Verification (GF/LSSCV). The GF/LSSCV's test article was well suited for this experiment in that the LMED could be judiciously placed on the ASTROMAST. The LMED placements were such that vibrational mode information could be extracted from the accelerometers on the LMED. The LMED accelerometer information was processed by the control algorithms so that the LMED masses could be accelerated to produce forces which would dampen the vibrational modes of interest. Experimental results are presented showing the LMED's capabilities.

  6. Electrically controlled exchange bias for spintronic applications

    NASA Astrophysics Data System (ADS)

    He, Xi; Polisetty, Srinivas; Binek, Christian

    2006-03-01

    Electrically controlled exchange bias (EB) is proposed for novel spintronic applications [1]. Basic effects of electrically controlled EB and its magnetoelectric (ME) switching are studied in a Cr2O3(111)/(Co/Pt)3 heterostructure. Exchange coupling between the ME antiferromagnet Cr2O3 and a ferromagnetic CoPt multilayer exhibits perpendicular EB. The latter is controlled by applied axial electric fields inducing excess magnetization at the interface. The enhancement of this hitherto weak tuning effect is explored when replacing ME bulk pinning systems by epitaxal thin films. Recently, the sign of the EB field has been tuned via field cooling the system in either parallel or antiparallel axial magnetic and electric fields [2].Here, the crossover from bulk to thin film ME pinning systems is studied and spintronic applications are suggested based on the electrically controlled EB. Pure voltage control of magnetic configurations of tunneling magnetoresistance spin valves is proposed as an alternative to current-induced magnetization switching. In addition we suggest an XOR operation realized in a MEally pinned giant magneto resistance structure. [1] Ch. Binek, B.Doudin, J. Phys. Condens. Matter 17, L39 (2005). [2] P. Borisov et al., Phys. Rev. Lett. 94, 117203 (2005).

  7. Aircraft digital flight control technical review

    NASA Technical Reports Server (NTRS)

    Davenport, Otha B.; Leggett, David B.

    1993-01-01

    The Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems. Consequently, a technical review team was formed to examine the development process and determine why PIO problems continued to occur. The team was also to identify the 'best practices' used in the various programs. The charter of the team was to focus on the PIO problem, assess the current development process, and document the 'best practices.' The team reviewed all major USAF aircraft programs with digital flight controls, specifically, the F-15E, F-16C/D, F-22, F-111, C-17, and B-2. The team interviewed contractor, System Program Office (SPO), and Combined Test Force (CTF) personnel on these programs. The team also went to NAS Patuxent River to interview USN personnel about the F/A-18 program. The team also reviewed experimental USAF and NASA systems with digital flight control systems: X-29, X-31, F-15 STOL and Maneuver Technology Demonstrator (SMTD), and the Variable In-Flight Stability Test Aircraft (VISTA). The team also discussed the problem with other experts in the field including Ralph Smith and personnel from Calspan. The major conclusions and recommendations from the review are presented.

  8. Proceedings of the efficient separations and processing crosscutting program 1997 technical exchange meeting

    SciTech Connect

    Gephart, J.M.

    1997-05-01

    This document contains summaries of technology development presented at the 1997 Efficient Separations and Processing Crosscutting Program (ESP-CP) Technical Exchange Meeting (TEM), held January 28-30, 1997, in Gaithersburg, Maryland. The ESP-CP is sponsored by the U.S. Department of Energy`s Office of Environmental Management (DOE/EM), Office of Science and Technology. The ESP-CP TEM is held annually to: (1) Present current technology development activities funded by the ESP-CP. Developers of ESP-CP-funded technologies describe the problems and needs addressed by their technologies; the technical approach, accomplishments, and resolution of issues; the strategy and schedule for commercialization; and evolving potential applications. Representatives from DOE/EM`s Focus Areas also present their technology needs. (2) Promote the exchange of technical information among those developing new separations technologies, those responsible for providing new separations technologies to meet DOE/EM needs, and those who need or will potentially make use of such technologies. (3) Familiarize the ESP-CP Technical Review Team with the FY 1997 program and solicit reviewers` views on the program as a whole. This meeting is not a program review of the individual tasks, but instead focuses on the technical aspects and implementation of ESP-CP-sponsored technology or data. This document also contains a list of ESP-CP-sponsored publications, presentations, and patents. Separate abstracts have been indexed into the energy database for contributions to this proceedings.

  9. NASA's experience in the international exchange of scientific and technical information in the aerospace field

    NASA Technical Reports Server (NTRS)

    Thibideau, Philip A.

    1989-01-01

    The early NASA international scientific and technical information (STI) exchange arrangements were usually detailed in correspondence with the librarians of the institutions involved. While this type of exchange, which involved only hardcopy (paper) products, grew to include some 220 organization in 43 countries, NASA's main focus shifted substantially to the STI relationship with the European Space Agency (ESA) which began in 1964. The NASA/ESA Tripartite Exchange Program, which now has more than 500 participants, provides more than 4,000 highly-relevant technical reports, fully processed, for the NASA produced 'Aerospace Database'. In turn, NASA provides an updated copy of this Database, known in Europe as the 'NASA File', for access, through ESA's Information Retrieval Service, by participating European organizations. Our experience in the evolving cooperation with ESA has established the 'model' for our more recent exchange agreements with Israel, Australia, Canada, and one under negotiation with Japan. The results of these agreements are made available to participating European organizations through the NASA File.

  10. NASA's experience in the international exchange of scientific and technical information in the aerospace field

    NASA Technical Reports Server (NTRS)

    Thibideau, Philip A.

    1989-01-01

    The early NASA international scientific and technical information (STI) exchange arrangements were usually detailed in correspondence with the librarians of the institutions involved. While this type of exchange, which involved only hardcopy (paper) products, grew to include some 220 organization in 43 countries, NASA's main focus shifted substantially to the STI relationship with the European Space Agency (ESA) which began in 1964. The NASA/ESA Tripartite Exchange Program, which now has more than 500 participants, provides more than 4,000 highly-relevant technical reports, fully processed, for the NASA produced 'Aerospace Database'. In turn, NASA provides an updated copy of this Database, known in Europe as the 'NASA File', for access, through ESA's Information Retrieval Service, by participating European organizations. Our experience in the evolving cooperation with ESA has established the 'model' for our more recent exchange agreements with Israel, Australia, Canada, and one under negotiation with Japan. The results of these agreements are made available to participating European organizations through the NASA File.

  11. Plasma exchange in the intensive care unit: Technical aspects and complications.

    PubMed

    Lemaire, Aurélie; Parquet, Nathalie; Galicier, Lionel; Boutboul, David; Bertinchamp, Rémi; Malphettes, Marion; Dumas, Guillaume; Mariotte, Eric; Peraldi, Marie-Noëlle; Souppart, Virginie; Schlemmer, Benoit; Azoulay, Elie; Canet, Emmanuel

    2017-02-01

    Data on plasma exchange therapy in the intensive care unit (ICU) setting are scarce. We aimed to describe the technical aspects and the adverse events associated with the procedure in critically ill patients. All adult patients treated by plasma exchange in the medical ICU of the Saint-Louis university hospital between January 1, 2013 and March 31, 2015 were prospectively included. We report on 260 plasma exchange procedures performed in 50 patients. The centrifugation technique was used for 159 (61%) procedures and the filtration technique for the other 101 (39%) procedures. Both techniques had similar efficacy to treat hyperviscosity syndrome (n = 18). Seventy (26.9%) of the 260 plasma exchange procedures were reported with at least one adverse reaction. Centrifugation and filtration techniques had similar rates of adverse reactions (23.9 vs. 31.7%, P = .19). Hypotension was the most reported (n = 21, 8%) and correlates with a low hematocrit before therapy. Most complications were related to allergic reactions to the replacement fluids. Coagulation disorders depended on the type of replacement fluid. The post-exchange fibrinogen level was decreased by 54% [48;66] with albumin 5%, and 4% [-5;17] with plasma frozen within 24 h. Twenty-three (22.8%) of the 101 filtration procedures experienced filter clotting. Filter clotting was associated with a higher volume exchange prescribed when compared to procedures without filter clotting (4600 [4000;5000] ml vs. 3900 [3600;4800] ml, P < .01). Plasma exchange is a relatively safe and generally well-tolerated procedure in the ICU setting. Most adverse events are unpredictable and related to minor allergic reactions. © 2017 Wiley Periodicals, Inc.

  12. PROGRAMED EXCHANGES AND THE CONTROL OF AGGRESSION.

    ERIC Educational Resources Information Center

    ELLIS, DESMOND P.; HAMBLIN, ROBERT L.

    SYSTEMS OF EXCHANGE - USING THE EXTINCTION, DISTRACTION, AND SUBSTITUTION EFFECTS SYSTEMS - WERE IMPLEMENTED TO DECREASE AGGRESSION AND PROMOTE COOPERATION AND SCHOLARLY BEHAVIOR, THREE SYSTEMS WERE TESTED USING EXCHANGE THEORY AS A GUIDE. THE SUBJECTS WERE FIVE 4- AND 5-YEAR-OLD BOYS DIAGNOSED AS HYPERAGGRESSIVE. EXPERIMENTAL CONDITIONS INCLUDED…

  13. Advanced Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Technical Exchange Meeting

    SciTech Connect

    Curtis Smith

    2013-09-01

    During FY13, the INL developed an advanced SMR PRA framework which has been described in the report Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Detailed Technical Framework Specification, INL/EXT-13-28974 (April 2013). In this framework, the various areas are considered: Probabilistic models to provide information specific to advanced SMRs Representation of specific SMR design issues such as having co-located modules and passive safety features Use of modern open-source and readily available analysis methods Internal and external events resulting in impacts to safety All-hazards considerations Methods to support the identification of design vulnerabilities Mechanistic and probabilistic data needs to support modeling and tools In order to describe this framework more fully and obtain feedback on the proposed approaches, the INL hosted a technical exchange meeting during August 2013. This report describes the outcomes of that meeting.

  14. (Technical exchange in robotics for reactor decommissioning between the USA and Japan)

    SciTech Connect

    Weisbin, C.R.

    1987-09-22

    Japan is one of the world leaders in artificial intelligence and robotics. A major collaborative program already exists between the ORNL CFRP effort in advanced teleoperations and the Japanese interest in remote handling for nuclear fuel reprocessing. The subject visit was stimulated by the Japanese to foster a broader exchange in the area of autonomous robotics and intelligent machines. Following a visit to CESAR approximately one year ago, JAERI proposed a similar initiative in intelligent autonomous machines. This effort (HASP) has been formally approved as a ten year program, and initiated in its first year with eight full-time researchers. Beginning next year, it is expected that this effort will grow to its maximum level of 25 researchers per year. Prospects for potential technical exchange in AI/robotics appear promising. Additional opportunities may exist in remote handling for reactor decommissioning.

  15. Technically exploitable geothermal energy by using Borehole Heat Exchangers: A revisit of the Cologne case

    NASA Astrophysics Data System (ADS)

    Shao, Haibing; Hein, Philipp; Bucher, Anke; Kolditz, Olaf

    2017-04-01

    In previous studies, the amount of shallow geothermal energy was estimated by assuming a uniform temperature drop of at least 2 °C in the aquifer. In this work, a more comprehensive numerical model has been employed to evaluate the technically exploitable geothermal energy by using Borehole Heat Exchanger coupled Ground Source Heat Pump systems. A case study on the city of Cologne was revisited, adopting the same hydrogeological conditions and simulating the long-term evolution of the subsurface temperature field subject to the operation of borehole heat exchangers. It is found that the cities' heating demand could potentially be fully covered by BHE-coupled GSHP systems. The resulting equivalent uniform temperature drop is then around 1.6 °C . It was also found that utilising geothermal energy will lead to at least 50% reduction of CO2 equivalent emission in comparison to conventional district heating, depending on the source of electricity used for heat pump operation.

  16. Control strategies in a thermal oil - Molten salt heat exchanger

    NASA Astrophysics Data System (ADS)

    Roca, Lidia; Bonilla, Javier; Rodríguez-García, Margarita M.; Palenzuela, Patricia; de la Calle, Alberto; Valenzuela, Loreto

    2016-05-01

    This paper presents a preliminary control scheme for a molten salt - thermal oil heat exchanger. This controller regulates the molten salt mass flow rate to reach and maintain the desired thermal oil temperature at the outlet of the heat exchanger. The controller architecture has been tested using an object-oriented heat exchanger model that has been validated with data from a molten salt testing facility located at CIEMAT-PSA. Different simulations are presented with three different goals: i) to analyze the controller response in the presence of disturbances, ii) to demonstrate the benefits of designing a setpoint generator and iii) to show the controller potential against electricity price variations.

  17. Identifying and responding to technical assistance and training needs in tobacco prevention and control.

    PubMed

    Thornton, Amber Hardy; Barrow, Madeline; Niemeyer, Dearell; Burrus, Barri; Gertel, Allison S; Krueger, Daniel; Mulvihill, Daniel W; Sneegas, Karla S

    2004-07-01

    The Master Settlement Agreement generated expectations that significant, long-term funding would be available to the 46 participating states in reparation for the health costs incurred by tobacco use. Facing intense pressure to use anticipated funds for effective programming, states and national organizations considered how to supply the technical assistance and training at the state and local levels. This article reviews assessments by the American Legacy Foundation, the Tobacco Technical Assistance Consortium, and selected states of the current needs for support, technical assistance, and training in tobacco prevention and control. Key findings indicated the need for information, information exchange, mentoring, and training targeted to new staff, with advanced skill sets for experienced staff. As future funding is uncertain, all these organizations are exploring innovative ways to maintain infrastructure and programming at the state and local levels. Training and technical assistance can be the solution to sustaining impetus in the movement.

  18. Profitability of simple technical trading rules of Chinese stock exchange indexes

    NASA Astrophysics Data System (ADS)

    Zhu, Hong; Jiang, Zhi-Qiang; Li, Sai-Ping; Zhou, Wei-Xing

    2015-12-01

    Although technical trading rules have been widely used by practitioners in financial markets, their profitability still remains controversial. We here investigate the profitability of moving average (MA) and trading range break (TRB) rules by using the Shanghai Stock Exchange Composite Index (SHCI) from May 21, 1992 through December 31, 2013 and Shenzhen Stock Exchange Component Index (SZCI) from April 3, 1991 through December 31, 2013. The t-test is adopted to check whether the mean returns which are conditioned on the trading signals are significantly different from unconditioned returns and whether the mean returns conditioned on the buy signals are significantly different from the mean returns conditioned on the sell signals. We find that TRB rules outperform MA rules and short-term variable moving average (VMA) rules outperform long-term VMA rules. By applying White's Reality Check test and accounting for the data snooping effects, we find that the best trading rule outperforms the buy-and-hold strategy when transaction costs are not taken into consideration. Once transaction costs are included, trading profits will be eliminated completely. Our analysis suggests that simple trading rules like MA and TRB cannot beat the standard buy-and-hold strategy for the Chinese stock exchange indexes.

  19. Soft Controls: Technical Basis and Human Factors Review Guidance

    DTIC Science & Technology

    2000-03-01

    Controlling Office is (insert controlling DoD office). NUREG /CR-6635 BNL- NUREG -52565 Soft Controls: Technical Basis and Human Factors Review Guidance...DC 20555-0001 AVAILABILITY NOTICE Availability of Reference Materials Cited in NRC Publications NRC publications in the NUREG series, NRC regu...Technical Information Service Springfield, VA 22161 -0002 <http://www.ntis.gov> 1 -800-553-6847 or locally 703-605-6000 The NUREG series

  20. Advanced Combustion and Emission Control Technical Team Roadmap

    SciTech Connect

    2013-06-01

    The Advanced Combustion and Emission Control (ACEC) Technical Team is focused on removing technical barriers to the commercialization of advanced, high-efficiency, emission-compliant internal combustion (IC) engines for light-duty vehicle powertrains (i.e., passenger car, minivan, SUV, and pickup trucks).

  1. Manipulating magnetism by ultrafast control of the exchange interaction.

    PubMed

    Mentink, J H

    2017-10-06

    In recent years, the optical control of exchange interactions has emerged as an exciting new direction in the study of the ultrafast optical control of magnetic order. Here we review recent theoretical works on antiferromagnetic systems, devoted to (i) simulating the ultrafast control of exchange interactions, (ii) modeling the strongly nonequilibrium response of the magnetic order and (iii) the relation with relevant experimental works developed in parallel. In addition to the excitation of spin precession, we discuss examples of rapid cooling and the control of ultrafast coherent longitudinal spin dynamics in response to femtosecond optically induced perturbations of exchange interactions. These elucidate the potential for exploiting the control of exchange interactions to find new scenarios for both faster and more energy-efficient manipulation of magnetism.

  2. Technical Developments for Harnessing Controlled Fusion

    NASA Astrophysics Data System (ADS)

    Veres, G.; Zoletnik, S.; Jacob, W.

    This chapter gives the conditions for achieving power production using nuclear fusion reactions. The two basic schemes for plasma confinement, inertial and magnetic, are briefly considered and the present technical solutions are outlined. The physical and chemical processes taking place between the hot plasma and the containing vessel wall are discussed in more detail. At the end of the chapter, the present status of research and the planned future development plans are summarized.

  3. Overcoming technical challenges when treating atypical hemolytic uremic syndrome with therapeutic plasma exchange.

    PubMed

    Zimbudzi, Edward

    2013-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a very rare, life-threatening, progressive disease that frequently has a genetic component and in most cases is triggered by an uncontrolled activation of the complement system. Successful treatment of aHUS with plasma infusions and therapeutic plasma exchange (TPE) is well reported. TPE has been the treatment of choice in most adult patients with aHUS. However, due to severe hemolysis, which is common among aHUS patients, there are some technical challenges that can affect TPE treatment such as the continuous activation of the blood leak alarm due to hemolysis. Our experience shows that such patients can be managed better on a centrifuge based TPE machine compared to a membrane based TPE machine.

  4. Technical Justification for Radiation Controls at an Environmental Laboratory

    SciTech Connect

    DUPAQUIER, J.C.

    2000-07-01

    This paper describes the technical approach used to establish radiation protection controls over incoming radioactive materials to an environmental measurements laboratory at the Hanford Site. Conditions that would trigger internal dosimetry, posting.

  5. Using technical assistance to strengthen tobacco control capacity: evaluation findings from the Tobacco Technical Assistance Consortium.

    PubMed

    Kegler, Michelle Crozier; Redmon, Pamela Buffington

    2006-01-01

    Immediately following the Master Settlement Agreement of 1998 and the corresponding growth of new and existing tobacco control programs, it became clear that tobacco prevention and control organizations required technical assistance to help them carry out their missions. The Tobacco Technical Assistance Consortium (TTAC) was established at the Rollins School of Public Health in 2001 to provide tailored technical assistance services to meet the needs of the expanded workforce and to build tobacco control capacity. To understand whether and how TTAC's technical assistance enhanced capacity, TTAC conducted an evaluation of its services through semi-structured telephone interviews with the primary contacts and one to two additional informants for each of 48 technical assistance services provided over an 18-month period. The majority of respondents reported they had increased knowledge and skills in tobacco control, strengthened leadership skills, developed or strengthened partnerships with other tobacco control organizations, and changed the way they practice tobacco control following the assistance. More modest improvements were noted in the areas of increased organizational support and policy change at the local or state level.

  6. Technical architecture of ONC-approved plans for statewide health information exchange.

    PubMed

    Barrows, Randolph C; Ezzard, John

    2011-01-01

    ONC-approved state plans for HIE were reviewed for descriptions and depictions of statewide HIE technical architecture. Review was complicated by non-standard organizational elements and technical terminology across state plans. Findings were mapped to industry standard, referenced, and defined HIE architecture descriptions and characteristics. Results are preliminary due to the initial subset of ONC-approved plans available, the rapid pace of new ONC-plan approvals, and continuing advancements in standards and technology of HIE, etc. Review of 28 state plans shows virtually all include a direct messaging component, but for participating entities at state-specific levels of granularity (RHIO, enterprise, organization/provider). About ½ of reviewed plans describe a federated architecture, and ¼ of plans utilize a single-vendor "hybrid-federated" architecture. About 1/3 of states plan to leverage new federal and open exchange technologies (DIRECT, CONNECT, etc.). Only one plan describes a centralized architecture for statewide HIE, but others combine central and federated architectural approaches.

  7. Technical Architecture of ONC-Approved Plans For Statewide Health Information Exchange

    PubMed Central

    Barrows, Randolph C.; Ezzard, John

    2011-01-01

    ONC-approved state plans for HIE were reviewed for descriptions and depictions of statewide HIE technical architecture. Review was complicated by non-standard organizational elements and technical terminology across state plans. Findings were mapped to industry standard, referenced, and defined HIE architecture descriptions and characteristics. Results are preliminary due to the initial subset of ONC-approved plans available, the rapid pace of new ONC-plan approvals, and continuing advancements in standards and technology of HIE, etc. Review of 28 state plans shows virtually all include a direct messaging component, but for participating entities at state-specific levels of granularity (RHIO, enterprise, organization/provider). About ½ of reviewed plans describe a federated architecture, and ¼ of plans utilize a single-vendor “hybrid-federated” architecture. About 1/3 of states plan to leverage new federal and open exchange technologies (DIRECT, CONNECT, etc.). Only one plan describes a centralized architecture for statewide HIE, but others combine central and federated architectural approaches. PMID:22195059

  8. Learning from Health Information Exchange Technical Architecture and Implementation in Seven Beacon Communities

    PubMed Central

    McCarthy, Douglas B.; Propp, Karen; Cohen, Alexander; Sabharwal, Raj; Schachter, Abigail A.; Rein, Alison L.

    2014-01-01

    As health care providers adopt and make “meaningful use” of health information technology (health IT), communities and delivery systems must set up the infrastructure to facilitate health information exchange (HIE) between providers and numerous other stakeholders who have a role in supporting health and care. By facilitating better communication and coordination between providers, HIE has the potential to improve clinical decision-making and continuity of care, while reducing unnecessary use of services. When implemented as part of a broader strategy for health care delivery system and payment reform, HIE capability also can enable the use of analytic tools needed for population health management, patient engagement in care, and continuous learning and improvement. The diverse experiences of seven communities that participated in the three-year federal Beacon Community Program offer practical insight into factors influencing the technical architecture of exchange infrastructure and its role in supporting improved care, reduced cost, and a healthier population. The case studies also document challenges faced by the communities, such as significant time and resources required to harmonize variations in the interpretation of data standards. Findings indicate that their progress developing community-based HIE strategies, while driven by local needs and objectives, is also influenced by broader legal, policy, and market conditions. PMID:25848591

  9. Learning from health information exchange technical architecture and implementation in seven beacon communities.

    PubMed

    McCarthy, Douglas B; Propp, Karen; Cohen, Alexander; Sabharwal, Raj; Schachter, Abigail A; Rein, Alison L

    2014-01-01

    As health care providers adopt and make "meaningful use" of health information technology (health IT), communities and delivery systems must set up the infrastructure to facilitate health information exchange (HIE) between providers and numerous other stakeholders who have a role in supporting health and care. By facilitating better communication and coordination between providers, HIE has the potential to improve clinical decision-making and continuity of care, while reducing unnecessary use of services. When implemented as part of a broader strategy for health care delivery system and payment reform, HIE capability also can enable the use of analytic tools needed for population health management, patient engagement in care, and continuous learning and improvement. The diverse experiences of seven communities that participated in the three-year federal Beacon Community Program offer practical insight into factors influencing the technical architecture of exchange infrastructure and its role in supporting improved care, reduced cost, and a healthier population. The case studies also document challenges faced by the communities, such as significant time and resources required to harmonize variations in the interpretation of data standards. Findings indicate that their progress developing community-based HIE strategies, while driven by local needs and objectives, is also influenced by broader legal, policy, and market conditions.

  10. Gas controller's paper pipeline - transportation and exchange

    SciTech Connect

    Chapman, R.E. Jr.

    1981-01-01

    When gas supplies began to decline during the 1970s, the US Federal Energy Regulatory Commission promulgated Orders 402 and 402-A to allow curtailed companies to make 60-day emergency purchases. In assisting its customer companies with such transactions, Texas Gas encountered several problems: the gas had to be allocated to each company, the sales required separate billing, the allocated volumes had to be received and delivered, and new contracts were necessary. Another stopgap measure, known as the 533 transportation service, also proved difficult to implement because the gas volumes were usually very small and were often interrupted when regular supplies began to resume. Under the Natural Gas Policy Act of 1978, interstate companies could offer the same gas prices to producers that intrastate companies paid; the NGPA also allowed sales from intra- to interstate companies. These provisions created a greater need for transportation-or-exchange service among all the parties. More recently, the FERC's Order 60 gave interstate companies the power to enter into self-implementing transportation-or-exchange service. Under legal modifications now being considered, pipeline companies will be able to significantly reduce regulatory delays by using blanket certificates.

  11. Primer Control System Cyber Security Framework and Technical Metrics

    SciTech Connect

    Wayne F. Boyer; Miles A. McQueen

    2008-05-01

    The Department of Homeland Security National Cyber Security Division supported development of a control system cyber security framework and a set of technical metrics to aid owner-operators in tracking control systems security. The framework defines seven relevant cyber security dimensions and provides the foundation for thinking about control system security. Based on the developed security framework, a set of ten technical metrics are recommended that allow control systems owner-operators to track improvements or degradations in their individual control systems security posture.

  12. The NASA Scientific and Technical Information (STI) Program's Implementation of Open Archives Initiative (OAI) for Data Interoperability and Data Exchange.

    ERIC Educational Resources Information Center

    Rocker, JoAnne; Roncaglia, George J.; Heimerl, Lynn N.; Nelson, Michael L.

    Interoperability and data-exchange are critical for the survival of government information management programs. E-government initiatives are transforming the way the government interacts with the public. More information is to be made available through Web-enabled technologies. Programs such as the NASA's Scientific and Technical Information (STI)…

  13. Control of the Oscillatory Interlayer Exchange Interaction with Terahertz Radiation

    NASA Astrophysics Data System (ADS)

    Meyer, Uta; Haack, Géraldine; Groth, Christoph; Waintal, Xavier

    2017-03-01

    The oscillatory interlayer exchange interaction between two magnetic layers separated by a metallic spacer is one of the few coherent quantum phenomena that persists at room temperature. Here, we show that this interaction can be controlled dynamically by illuminating the sample (e.g., a spin valve) with radiation in the 10-100 THz range. We predict that the exchange interaction can be changed from ferromagnetic to antiferromagnetic (and vice versa) by tuning the amplitude and/or the frequency of the radiation. Our chief theoretical result is an expression that relates the dynamical exchange interaction to the static one that has already been extensively measured.

  14. The predictive protective control of the heat exchanger

    NASA Astrophysics Data System (ADS)

    Nevriva, Pavel; Filipova, Blanka; Vilimec, Ladislav

    2016-06-01

    The paper deals with the predictive control applied to flexible cogeneration energy system FES. FES was designed and developed by the VITKOVICE POWER ENGINEERING joint-stock company and represents a new solution of decentralized cogeneration energy sources. In FES, the heating medium is flue gas generated by combustion of a solid fuel. The heated medium is power gas, which is a gas mixture of air and water steam. Power gas is superheated in the main heat exchanger and led to gas turbines. To protect the main heat exchanger against damage by overheating, the novel predictive protective control based on the mathematical model of exchanger was developed. The paper describes the principle, the design and the simulation of the predictive protective method applied to main heat exchanger of FES.

  15. Control of quantum magnets by atomic exchange bias.

    PubMed

    Yan, Shichao; Choi, Deung-Jang; Burgess, Jacob A J; Rolf-Pissarczyk, Steffen; Loth, Sebastian

    2015-01-01

    Mixing of discretized states in quantum magnets has a radical impact on their properties. Managing this effect is key for spintronics in the quantum limit. Magnetic fields can modify state mixing and, for example, mitigate destabilizing effects in single-molecule magnets. The exchange bias field has been proposed as a mechanism for localized control of individual nanomagnets. Here, we demonstrate that exchange coupling with the magnetic tip of a scanning tunnelling microscope provides continuous tuning of spin state mixing in an individual nanomagnet. By directly measuring spin relaxation time with electronic pump-probe spectroscopy, we find that the exchange interaction acts analogously to a local magnetic field that can be applied to a specific atom. It can be tuned in strength by up to several tesla and cancel external magnetic fields, thereby demonstrating the feasibility of complete control over individual quantum magnets with atomically localized exchange coupling.

  16. Control of quantum magnets by atomic exchange bias

    NASA Astrophysics Data System (ADS)

    Yan, Shichao; Choi, Deung-Jang; Burgess, Jacob A. J.; Rolf-Pissarczyk, Steffen; Loth, Sebastian

    2015-01-01

    Mixing of discretized states in quantum magnets has a radical impact on their properties. Managing this effect is key for spintronics in the quantum limit. Magnetic fields can modify state mixing and, for example, mitigate destabilizing effects in single-molecule magnets. The exchange bias field has been proposed as a mechanism for localized control of individual nanomagnets. Here, we demonstrate that exchange coupling with the magnetic tip of a scanning tunnelling microscope provides continuous tuning of spin state mixing in an individual nanomagnet. By directly measuring spin relaxation time with electronic pump-probe spectroscopy, we find that the exchange interaction acts analogously to a local magnetic field that can be applied to a specific atom. It can be tuned in strength by up to several tesla and cancel external magnetic fields, thereby demonstrating the feasibility of complete control over individual quantum magnets with atomically localized exchange coupling.

  17. Temperature control system for a J-module heat exchanger

    DOEpatents

    Basdekas, Demetrios L.; Macrae, George; Walsh, Joseph M.

    1978-01-01

    The level of primary fluid is controlled to change the effective heat transfer area of a heat exchanger utilized in a liquid metal nuclear power plant to eliminate the need for liquid metal control valves to regulate the flow of primary fluid and the temperature of the effluent secondary fluid.

  18. Exchange Controls, Investment and the Balance of Payments.

    ERIC Educational Resources Information Center

    James, Stephen

    1986-01-01

    Exchange controls in Great Britain were abolished in 1979. Since then, there has been a significant outflow of capital. This article examines the case for the reintroduction of controls with particular reference to the effect this might have on investment. (Author/JDH)

  19. Exchange Controls, Investment and the Balance of Payments.

    ERIC Educational Resources Information Center

    James, Stephen

    1986-01-01

    Exchange controls in Great Britain were abolished in 1979. Since then, there has been a significant outflow of capital. This article examines the case for the reintroduction of controls with particular reference to the effect this might have on investment. (Author/JDH)

  20. Technical Seminar: "Towards Intelligent Flight Control"

    NASA Image and Video Library

    The idea behind intelligent flight control is to provide more autonomy in an aircraft cockpit. Such systems must allow for all different kinds of situations and for human factors that occur in loss...

  1. Ideal Based Cyber Security Technical Metrics for Control Systems

    SciTech Connect

    W. F. Boyer; M. A. McQueen

    2007-10-01

    Much of the world's critical infrastructure is at risk from attack through electronic networks connected to control systems. Security metrics are important because they provide the basis for management decisions that affect the protection of the infrastructure. A cyber security technical metric is the security relevant output from an explicit mathematical model that makes use of objective measurements of a technical object. A specific set of technical security metrics are proposed for use by the operators of control systems. Our proposed metrics are based on seven security ideals associated with seven corresponding abstract dimensions of security. We have defined at least one metric for each of the seven ideals. Each metric is a measure of how nearly the associated ideal has been achieved. These seven ideals provide a useful structure for further metrics development. A case study shows how the proposed metrics can be applied to an operational control system.

  2. Ion Exchange Conceptual Design for Treating Seven Technical Area Sumps with Elevated Levels of Copper and Zinc

    SciTech Connect

    Oji, L.N.

    1999-02-17

    Recently a meeting was held to discuss technical support for developing a conceptual design and estimate for installing and operating an in-line ion exchange system to treat seven Technical Area Sumps with elevated levels (high ppb - low ppm) of copper and potentially zinc (copper level is above the outfall limits). These sump waters are currently routed to the A01 outfall, which is permitted by the State of South Carolina. a study of potential treatment options and followup laboratory work done in the summer of 1997 by Larry Oji and John Hage identified two commercially available ion exchange resins, Duolit GT-73 and Chelex 100, for treating waters at these metals concentrations.

  3. Indian - Atlantic interocean exchange: variability and controls

    NASA Astrophysics Data System (ADS)

    Schouten, Mathijs Wilhelmus

    2002-05-01

    South of Africa, warm Indian Ocean water enters the Atlantic Ocean by means of large Agulhas Rings. These rings, with diameters up to 350 km and reaching all the way to the ocean floor at 5 km depth, form an important link in the global thermohaline circulation, which is the driving force behind the moderate temperatures over Northern Europe. For six years, the shedding of Agulhas rings has been monitored from space, using satellite altimeter measurements of the sea surface height. Rings can be identified by sea surface elevations on the order of 20-50 cm. The rings are followed on their way westward through the Atlantic, where they gradually decay. The decay is found to take place mainly in the Cape Basin during the first year after formation, probably delivering most of the Ring's thermohaline contents to this region. Also, rings are observed to often split into smaller rings. The shedding of Agulhas Rings is shown to be related to upstream processes. Especially, eddies from the Mozambique Channel are found to control the timing of Agulhas Ring shedding. These Mozambique Eddies have recently been measured to be dynamically comparable to the energetic Agulhas Rings, to carry tropical water masses southward through the Mozambique Channel, and to induce strong mixing in the channel. They in turn seem to be part of a mode of variability that is found over much of the Indian Ocean. A four-per-year signal is found to originate in the equatorial part of the Indian Ocean, and to propagate by a sequence of Kelvin and Rossby waves into the Mozambique Channel. Kelvin waves at the equator are forced by the semi-annual westerly windbursts that occur during the change of the monsoons. The frequency of these waves is doubled to four, probably by resonance of an equatorial basin mode. Four Kelvin waves per year are observed to reach the Indonesian coast, where they travel southward as coastal Kelvin waves. These force baroclinic Rossby waves at subtropical latitudes, which

  4. 77 FR 43196 - Minimum Internal Control Standards and Technical Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-24

    ... From the Federal Register Online via the Government Publishing Office NATIONAL INDIAN GAMING COMMISSION 25 CFR Parts 543 and 547 Minimum Internal Control Standards and Technical Standards AGENCY: National Indian Gaming Commission. ACTION: Proposed rule; extension of comment period. SUMMARY: On June 1...

  5. Control and Measurement of an Exchange-Only Spin Qubit

    NASA Astrophysics Data System (ADS)

    Medford, James

    2015-03-01

    Gate-defined semiconductor quantum dots have proven to be a versatile testbed for exploring quantum systems and quantum information. We demonstrate the fast all-electrical control of a spin qubit using the two coherent exchange interactions in a triple quantum dot. Our measurements identify the role of nuclear spins from the host GaAs in this system as a mechanism for both dephasing and leakage out of the qubit subspace. We also show that by increasing both exchange interactions in a balanced fashion, we enter a second regime of operation. In this regime, leakage from the subspace has been suppressed, resulting in a spin qubit with a tunable electric dipole moment, which we refer to as the resonant exchange qubit.

  6. Robust isothermal electric control of exchange bias at room temperature

    NASA Astrophysics Data System (ADS)

    Binek, Christian

    2011-03-01

    Voltage-controlled spintronics is of particular importance to continue progress in information technology through reduced power consumption, enhanced processing speed, integration density, and functionality in comparison with present day CMOS electronics. Almost all existing and prototypical solid-state spintronic devices rely on tailored interface magnetism, enabling spin-selective transmission or scattering of electrons. Controlling magnetism at thin-film interfaces, preferably by purely electrical means, is a key challenge to better spintronics. Currently, most attempts to electrically control magnetism focus on potentially large magnetoelectric effects of multiferroics. We report on our interest in magnetoelectric Cr 2 O3 (chromia). Robust isothermal electric control of exchange bias is achieved at room temperature in perpendicular anisotropic Cr 2 O3 (0001)/CoPd exchange bias heterostructures. This discovery promises significant implications for potential spintronics. From the perspective of basic science, our finding serves as macroscopic evidence for roughness-insensitive and electrically controllable equilibrium boundary magnetization in magnetoelectric antiferromagnets. The latter evolves at chromia (0001) surfaces and interfaces when chromia is in one of its two degenerate antiferromagnetic single domain states selected via magnetoelectric annealing. Theoretical insight into the boundary magnetization and its role in electrically controlled exchange bias is gained from first-principles calculations and general symmetry arguments. Measurements of spin-resolved ultraviolet photoemission, magnetometry at Cr 2 O3 (0001) surfaces, and detailed investigations of the unique exchange bias properties of Cr 2 O3 (0001)/CoPd including its electric controllability provide macroscopically averaged information about the boundary magnetization of chromia. Laterally resolved X-ray PEEM and temperature dependent MFM reveal detailed microscopic information of the chromia

  7. 77 FR 9218 - Tribally Controlled Postsecondary Career and Technical Institutions Program; Proposed Waivers and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-16

    ... Tribally Controlled Postsecondary Career and Technical Institutions Program; Proposed Waivers and Extension... the Tribally Controlled Postsecondary Career and Technical Institutions Program (TCPCTIP), the..., should there be one. Eligible applicants for TCPCTIP are tribally controlled postsecondary career...

  8. Measurable Control System Security through Ideal Driven Technical Metrics

    SciTech Connect

    Miles McQueen; Wayne Boyer; Sean McBride; Marie Farrar; Zachary Tudor

    2008-01-01

    The Department of Homeland Security National Cyber Security Division supported development of a small set of security ideals as a framework to establish measurable control systems security. Based on these ideals, a draft set of proposed technical metrics was developed to allow control systems owner-operators to track improvements or degradations in their individual control systems security posture. The technical metrics development effort included review and evaluation of over thirty metrics-related documents. On the bases of complexity, ambiguity, or misleading and distorting effects the metrics identified during the reviews were determined to be weaker than necessary to aid defense against the myriad threats posed by cyber-terrorism to human safety, as well as to economic prosperity. Using the results of our metrics review and the set of security ideals as a starting point for metrics development, we identified thirteen potential technical metrics - with at least one metric supporting each ideal. Two case study applications of the ideals and thirteen metrics to control systems were then performed to establish potential difficulties in applying both the ideals and the metrics. The case studies resulted in no changes to the ideals, and only a few deletions and refinements to the thirteen potential metrics. This led to a final proposed set of ten core technical metrics. To further validate the security ideals, the modifications made to the original thirteen potential metrics, and the final proposed set of ten core metrics, seven separate control systems security assessments performed over the past three years were reviewed for findings and recommended mitigations. These findings and mitigations were then mapped to the security ideals and metrics to assess gaps in their coverage. The mappings indicated that there are no gaps in the security ideals and that the ten core technical metrics provide significant coverage of standard security issues with 87% coverage. Based

  9. Server-Controlled Identity-Based Authenticated Key Exchange

    NASA Astrophysics Data System (ADS)

    Guo, Hua; Mu, Yi; Zhang, Xiyong; Li, Zhoujun

    We present a threshold identity-based authenticated key exchange protocol that can be applied to an authenticated server-controlled gateway-user key exchange. The objective is to allow a user and a gateway to establish a shared session key with the permission of the back-end servers, while the back-end servers cannot obtain any information about the established session key. Our protocol has potential applications in strong access control of confidential resources. In particular, our protocol possesses the semantic security and demonstrates several highly-desirable security properties such as key privacy and transparency. We prove the security of the protocol based on the Bilinear Diffie-Hellman assumption in the random oracle model.

  10. Safety Control and Safety Education at Technical Institutes

    NASA Astrophysics Data System (ADS)

    Iino, Hiroshi

    The importance of safety education for students at technical institutes is emphasized on three grounds including safety of all working members and students in their education, research and other activities. The Kanazawa Institute of Technology re-organized the safety organization into a line structure and improved safety minds of all their members and now has a chemical materials control system and a set of compulsory safety education programs for their students, although many problems still remain.

  11. EXCHANGE

    SciTech Connect

    Boltz, J.C.

    1992-09-01

    EXCHANGE is published monthly by the Idaho National Engineering Laboratory (INEL), a multidisciplinary facility operated for the US Department of Energy (DOE). The purpose of EXCHANGE is to inform computer users about about recent changes and innovations in both the mainframe and personal computer environments and how these changes can affect work being performed at DOE facilities.

  12. The NASA Scientific and Technical Information (STI) Program's Implementation of Open Archives Initiation (OAI) for Data Interoperability and Data Exchange

    NASA Technical Reports Server (NTRS)

    Rocker, JoAnne; Roncaglia, George J.; Heimerl, Lynn N.; Nelson, Michael L.

    2002-01-01

    Interoperability and data-exchange are critical for the survival of government information management programs. E-government initiatives are transforming the way the government interacts with the public. More information is to be made available through web-enabled technologies. Programs such as the NASA's Scientific and Technical Information (STI) Program Office are tasked to find more effective ways to disseminate information to the public. The NASA STI Program is an agency-wide program charged with gathering, organizing, storing, and disseminating NASA-produced information for research and public use. The program is investigating the use of a new protocol called the Open Archives Initiative (OAI) as a means to improve data interoperability and data collection. OAI promotes the use of the OAI harvesting protocol as a simple way for data sharing among repositories. In two separate initiatives, the STI Program is implementing OAI In collaboration with the Air Force, Department of Energy, and Old Dominion University, the NASA STI Program has funded research on implementing the OAI to exchange data between the three organizations. The second initiative is the deployment of OAI for the NASA technical report server (TRS) environment. The NASA TRS environment is comprised of distributed technical report servers with a centralized search interface. This paper focuses on the implementation of OAI to promote interoperability among diverse data repositories.

  13. Controlled trial of plasma exchange in treatment of Raynaud's syndrome.

    PubMed Central

    O'Reilly, M J; Talpos, G; Roberts, V C; White, J M; Cotton, L T

    1979-01-01

    Twenty-seven patients with Raynaud's syndrome had their digital vessel patency assessed by Doppler ultrasound after different thermal stresses. Digital vessel patency rates differed significantly after stresses at 15 degrees C and 45 degrees C. In a randomised controlled trial placebo and heparin had no effect either on patients' symptoms or on the patency of their digital vessels. Plasma exchange improved both symptoms and vessel patency rates at 15 degrees C and 21 degrees C. Improvement in seven out of eight of these patients has been maintained for six months. Assessing digital vessel patency by Doppler techniques allow continuous, atraumatic, and safe evaluation of the effects of different methods of treatment on the patency of the digital vessels and has helped to indicate that plasma exchange is a useful adjunct in the management of patients with severe Raynaud's syndrome. PMID:376042

  14. Mental practice enhances surgical technical skills: a randomized controlled study.

    PubMed

    Arora, Sonal; Aggarwal, Rajesh; Sirimanna, Pramudith; Moran, Aidan; Grantcharov, Teodor; Kneebone, Roger; Sevdalis, Nick; Darzi, Ara

    2011-02-01

    To assess the effects of mental practice on surgical performance. Increasing concerns for patient safety have highlighted a need for alternative training strategies outside the operating room. Mental practice (MP), "the cognitive rehearsal of a task before performance," has been successful in sport and music to enhance skill. This study investigates whether MP enhances performance in laparoscopic surgery. After baseline skills testing, 20 novice surgeons underwent training on an evidence-based virtual reality curriculum. After randomization using the closed envelope technique, all participants performed 5 Virtual Reality (VR) laparoscopic cholecystectomies (LC). Mental practice participants performed 30 minutes of MP before each LC; control participants viewed an online lecture. Technical performance was assessed using video Objective Structured Assessment of Technical Skills-based global ratings scale (scored from 7 to 35). Mental imagery was assessed using a previously validated Mental Imagery Questionnaire. Eighteen participants completed the study. There were no intergroup differences in baseline technical ability. Learning curves were demonstrated for both MP and control groups. Mental practice was superior to control (global ratings) for the first LC (median 20 vs 15, P = 0.005), second LC (20.5 vs 13.5, P = 0.001), third LC (24 vs 15.5, P < 0.001), fourth LC (25.5 vs 15.5, P < 0.001) and the fifth LC (27.5 vs 19.5, P = 0.00). The imagery for the MP group was also significantly superior to the control group across all sessions (P < 0.05). Improved imagery significantly correlated with better quality of performance (ρ 0.51–0.62, Ps < 0.05). This is the first randomized controlled study to show that MP enhances the quality of performance based on VR laparoscopic cholecystectomy. This may be a time- and cost-effective strategy to augment traditional training in the OR thus potentially improving patient care.

  15. Experiments on Socio-Technical Systems: The Problem of Control.

    PubMed

    Kroes, Peter

    2016-06-01

    My aim is to question whether the introduction of new technologies in society may be considered to be genuine experiments. I will argue that they are not, at least not in the sense in which the notion of experiment is being used in the natural and social sciences. If the introduction of a new technology in society is interpreted as an experiment, then we are dealing with a notion of experiment that differs in an important respect from the notion of experiment as used in the natural and social sciences. This difference shows itself most prominently when the functioning of the new technological system is not only dependent on technological hardware but also on social 'software', that is, on social institutions such as appropriate laws, and actions of operators of the new technological system. In those cases we are not dealing with 'simply' the introduction of a new technology, but with the introduction of a new socio-technical system. I will argue that if the introduction of a new socio-technical system is considered to be an experiment, then the relation between the experimenter and the system on which the experiment is performed differs significantly from the relation in traditional experiments in the natural and social sciences. In the latter experiments it is assumed that the experimenter is not part of the experimental system and is able to intervene in and control the experimental system from the outside. With regard to the introduction of new socio-technical systems the idea that there is an experimenter outside the socio-technical system who intervenes in and controls that system becomes problematic. From that perspective we are dealing with a different kind of experiment.

  16. Electric and Magnetic Field control of Exchange Bias

    NASA Astrophysics Data System (ADS)

    Binek, Christian

    2007-03-01

    Exchange bias (EB) and its accompanying training effect are fundamental interface phenomena in coupled magnetic thin films with significant impact in spintronic applications. Here we report on the electric field control of the EB in innovative antiferromagnetic (AF)/ferromagnetic (FM) heterostructures and the magnetic field control of the EB training effect in exchange coupled all FM bilayer systems. Electric control of the EB is realized in Cr2O3 (111)/(Co/Pt)3 heterostructures by taking advantage of the magnetoelectric (ME) properties of the AF pinning layer [1]. An electric field induces excess magnetization in the ME Cr2O3 film. Exchange coupling between the induced magnetization and the CoPt thin film gives rise to electrically controlled perpendicular EB. Bias fields are measured by means of AGFM, SQUID-magnetometry and polar Kerr-rotation. Electrically controlled EB is proposed for novel spintronic applications such as pure voltage control of magnetic configurations in spin valve-type architectures. The latter provide an attractive alternative to current-induced switching of the magnetization [2]. In addition, training of the EB effect is studied in novel all FM heterostructures of exchange coupled soft and hard FM thin films [3]. FM bilayers show remarkable analogies to the conventional AF/FM EB systems. Not only do they exhibit a tunable EB effect, they also show a distinct training behavior upon cycling the soft layer through consecutive hysteresis loops. In contrast to conventional EB systems, all FM bilayers allow the observation of training induced changes in the bias-setting hard layer by means of simple magnetometry. Initialization of the EB is achieved at constant temperature exclusively by means of magnetic fields. Our experiments show unambiguously that EB training is driven by deviations from the equilibrium spin configuration of the pinning layer. The experimental data show excellent agreement with our theoretical predictions including the

  17. Fault tolerance control for proton exchange membrane fuel cell systems

    NASA Astrophysics Data System (ADS)

    Wu, Xiaojuan; Zhou, Boyang

    2016-08-01

    Fault diagnosis and controller design are two important aspects to improve proton exchange membrane fuel cell (PEMFC) system durability. However, the two tasks are often separately performed. For example, many pressure and voltage controllers have been successfully built. However, these controllers are designed based on the normal operation of PEMFC. When PEMFC faces problems such as flooding or membrane drying, a controller with a specific design must be used. This paper proposes a unique scheme that simultaneously performs fault diagnosis and tolerance control for the PEMFC system. The proposed control strategy consists of a fault diagnosis, a reconfiguration mechanism and adjustable controllers. Using a back-propagation neural network, a model-based fault detection method is employed to detect the PEMFC current fault type (flooding, membrane drying or normal). According to the diagnosis results, the reconfiguration mechanism determines which backup controllers to be selected. Three nonlinear controllers based on feedback linearization approaches are respectively built to adjust the voltage and pressure difference in the case of normal, membrane drying and flooding conditions. The simulation results illustrate that the proposed fault tolerance control strategy can track the voltage and keep the pressure difference at desired levels in faulty conditions.

  18. 76 FR 49532 - Federal Motor Vehicle Safety Standards; Electronic Stability Control; Technical Report on the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... Control; Technical Report on the Effectiveness of Electronic Stability Control Systems for Cars and LTVs...: Request for comments on technical report. SUMMARY: This notice announces NHTSA's publication of a Technical Report on its existing Safety Standard 126, Electronic Stability Control Systems. The...

  19. Controllable positive exchange bias via redox-driven oxygen migration

    SciTech Connect

    Gilbert, Dustin A.; Olamit, Justin; Dumas, Randy K.; Kirby, B. J.; Grutter, Alexander J.; Maranville, Brian B.; Arenholz, Elke; Borchers, Julie A.; Liu, Kai

    2016-03-21

    We report that ionic transport in metal/oxide heterostructures offers a highly effective means to tailor material properties via modification of the interfacial characteristics. However, direct observation of ionic motion under buried interfaces and demonstration of its correlation with physical properties has been challenging. Using the strong oxygen affinity of gadolinium, we design a model system of GdxFe1-x/NiCoO bilayer films, where the oxygen migration is observed and manifested in a controlled positive exchange bias over a relatively small cooling field range. The exchange bias characteristics are shown to be the result of an interfacial layer of elemental nickel and cobalt, a few nanometres in thickness, whose moments are larger than expected from uncompensated NiCoO moments. This interface layer is attributed to a redox-driven oxygen migration from NiCoO to the gadolinium, during growth or soon after. Ultimately, these results demonstrate an effective path to tailoring the interfacial characteristics and interlayer exchange coupling in metal/oxide heterostructures.

  20. Controllable positive exchange bias via redox-driven oxygen migration

    PubMed Central

    Gilbert, Dustin A.; Olamit, Justin; Dumas, Randy K.; Kirby, B. J.; Grutter, Alexander J.; Maranville, Brian B.; Arenholz, Elke; Borchers, Julie A.; Liu, Kai

    2016-01-01

    Ionic transport in metal/oxide heterostructures offers a highly effective means to tailor material properties via modification of the interfacial characteristics. However, direct observation of ionic motion under buried interfaces and demonstration of its correlation with physical properties has been challenging. Using the strong oxygen affinity of gadolinium, we design a model system of GdxFe1−x/NiCoO bilayer films, where the oxygen migration is observed and manifested in a controlled positive exchange bias over a relatively small cooling field range. The exchange bias characteristics are shown to be the result of an interfacial layer of elemental nickel and cobalt, a few nanometres in thickness, whose moments are larger than expected from uncompensated NiCoO moments. This interface layer is attributed to a redox-driven oxygen migration from NiCoO to the gadolinium, during growth or soon after. These results demonstrate an effective path to tailoring the interfacial characteristics and interlayer exchange coupling in metal/oxide heterostructures. PMID:26996674

  1. Controllable positive exchange bias via redox-driven oxygen migration

    DOE PAGES

    Gilbert, Dustin A.; Olamit, Justin; Dumas, Randy K.; ...

    2016-03-21

    We report that ionic transport in metal/oxide heterostructures offers a highly effective means to tailor material properties via modification of the interfacial characteristics. However, direct observation of ionic motion under buried interfaces and demonstration of its correlation with physical properties has been challenging. Using the strong oxygen affinity of gadolinium, we design a model system of GdxFe1-x/NiCoO bilayer films, where the oxygen migration is observed and manifested in a controlled positive exchange bias over a relatively small cooling field range. The exchange bias characteristics are shown to be the result of an interfacial layer of elemental nickel and cobalt, amore » few nanometres in thickness, whose moments are larger than expected from uncompensated NiCoO moments. This interface layer is attributed to a redox-driven oxygen migration from NiCoO to the gadolinium, during growth or soon after. Ultimately, these results demonstrate an effective path to tailoring the interfacial characteristics and interlayer exchange coupling in metal/oxide heterostructures.« less

  2. Simulation-based ureteroscopy skills training curriculum with integration of technical and non-technical skills: a randomised controlled trial.

    PubMed

    Brunckhorst, Oliver; Shahid, Shahab; Aydin, Abdullatif; McIlhenny, Craig; Khan, Shahid; Raza, Syed Johar; Sahai, Arun; Brewin, James; Bello, Fernando; Kneebone, Roger; Khan, Muhammad Shamim; Dasgupta, Prokar; Ahmed, Kamran

    2015-09-01

    Current training modalities within ureteroscopy have been extensively validated and must now be integrated within a comprehensive curriculum. Additionally, non-technical skills often cause surgical error and little research has been conducted to combine this with technical skills teaching. This study therefore aimed to develop and validate a curriculum for semi-rigid ureteroscopy, integrating both technical and non-technical skills teaching within the programme. Delphi methodology was utilised for curriculum development and content validation, with a randomised trial then conducted (n = 32) for curriculum evaluation. The developed curriculum consisted of four modules; initially developing basic technical skills and subsequently integrating non-technical skills teaching. Sixteen participants underwent the simulation-based curriculum and were subsequently assessed, together with the control cohort (n = 16) within a full immersion environment. Both technical (Time to completion, OSATS and a task specific checklist) and non-technical (NOTSS) outcome measures were recorded with parametric and non-parametric analyses used depending on the distribution of our data as evaluated by a Shapiro-Wilk test. Improvements within the intervention cohort demonstrated educational value across all technical and non-technical parameters recorded, including time to completion (p < 0.01), OSATS scores (p < 0.001), task specific checklist scores (p = 0.011) and NOTSS scores (p < 0.001). Content validity, feasibility and acceptability were all demonstrated through curriculum development and post-study questionnaire results. The current developed curriculum demonstrates that integrating both technical and non-technical skills teaching is both educationally valuable and feasible. Additionally, the curriculum offers a validated simulation-based training modality within ureteroscopy and a framework for the development of other simulation-based programmes.

  3. Controls of Carbon Exchange in a Boreal Minerogenic Mire

    NASA Astrophysics Data System (ADS)

    Nilsson, M.; Sagerfors, J.; Buffam, I.; Eriksson, T.; Grelle, A.; Klemedtsson, L.; Weslien, P.; Laudon, H.; Lindroth, A.

    2008-12-01

    Based on theories on both mire development and their response to environmental change, the current role of mires as a net carbon sink has been questioned. A rigorous evaluation of the contemporary net C-exchange in mires requires direct measurements of all relevant fluxes. We use data on carbon exchange from a boreal minerogenic oligotrophic mire (Degerö Stormyr, 64°11' N, 19°33E) to derive a contemporary carbon budget and to analyze the main controls on the C exchange. Data on the following fluxes were collected: land-atmosphere CO2 (continuous Eddy Covariance measurements, 7 years) and CH4 (static chambers during the snow free period, 4 years) exchange; DOC in precipitation; loss of TOC, CO2 and CH4 through water runoff, 4 years (continuous discharge measurement and regular C-content measurements). The annual land atmosphere exchange of CO2 (NEE) was fairly constant between years and varied between -48 - -61 gCm-2yr-1 during six out of the seven years, despite a large variation in weather combinations, the average being -53 ± 5 gCm-2yr-1. Of the net fixation of atmospheric CO2-C during the net uptake period, i.e. the growing season, approximately a third was lost during the net source period, i.e. the winter period. During the four years with measurements of methane and runoff C-export another third of the growing season uptake was lost from the mire ecosystem as methane and runoff C. While the balance between the length of the NEE uptake and the NEE loss period are most important for the annual net ecosystem carbon balance (NECB) it is central to understand the controls of the spring-summer, and the summer-autumn transitions. The onset of the net C uptake period was controlled by the interaction between the water content and the temperature of the peat moss surface. We interpret this as mainly being a control of the CO2 photosynthesis uptake by the Sphagnum mosses. The transition from being a net C sink to being a net C source is in contrast only controlled

  4. Control of Methane Production and Exchange in Northern Peatlands

    NASA Technical Reports Server (NTRS)

    Crill, Patrick

    1997-01-01

    This proposal has successfully supported studies that have developed unique long ten-n datasets of methane (CH4) emissions and carbon dioxide (CO2) exchange in order to quantify the controls on CH4 production and exchange especially the linkages to the carbon cycle in northern peatlands. The primary research site has been a small fen in southeastern New Hampshire where a unique multi-year data baseline of CH4 flux measurements was begun (with NASA funding) in 1989. The fen has also been instrumented for continuous hydrological and meteorological observations and year-round porewater sampling. Multiyear datasets of methane flux are very valuable and very rare. Datasets using the same sampling techniques at the same sites are the only way to assess the effect of the integrated ecosystem response to climatological variability. The research has had two basic objectives: 1. To quantify the effect of seasonal and interannual variability on CH4flux. 2. To examine process level controls on methane dynamics.

  5. Robust isothermal electric control of exchange bias at room temperature.

    PubMed

    He, Xi; Wang, Yi; Wu, Ning; Caruso, Anthony N; Vescovo, Elio; Belashchenko, Kirill D; Dowben, Peter A; Binek, Christian

    2010-07-01

    Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with high-speed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr(2)O(3) has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr(2)O(3) single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias field between positive and negative values by reversing the electric field while maintaining a permanent magnetic field. This effect reflects the switching of the bulk antiferromagnetic domain state and the interface magnetization coupled to it. The switchable exchange bias sets in exactly at the bulk Néel temperature.

  6. Robust isothermal electric control of exchange bias at room temperature

    NASA Astrophysics Data System (ADS)

    He, Xi; Wang, Yi; Wu, Ning; Caruso, Anthony N.; Vescovo, Elio; Belashchenko, Kirill D.; Dowben, Peter A.; Binek, Christian

    2010-07-01

    Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with high-speed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias field between positive and negative values by reversing the electric field while maintaining a permanent magnetic field. This effect reflects the switching of the bulk antiferromagnetic domain state and the interface magnetization coupled to it. The switchable exchange bias sets in exactly at the bulk Néel temperature.

  7. Robust isothermal electric control of exchange bias at room temperature

    SciTech Connect

    He, X.; Vescovo, E.; Wang, Y.; Caruso, A.N.; Belashchenko, K.D.; Dowben, P.A.; Binek, C.

    2010-06-20

    Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with high-speed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr{sub 2}O{sub 3} has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr{sub 2}O{sub 3} single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias field between positive and negative values by reversing the electric field while maintaining a permanent magnetic field. This effect reflects the switching of the bulk antiferromagnetic domain state and the interface magnetization coupled to it. The switchable exchange bias sets in exactly at the bulk Neel temperature.

  8. Japan-U. S. technical information exchange: a one-way street

    SciTech Connect

    Rubinger, B.

    1985-03-01

    This study examines the status of Japanese research and technical developments in seven critical areas, and the ability of U.S. researchers to follow these developments. This work involved several fields critical to automotive advancement, including structural ceramics and combustion. The assessment found that researchers have difficulty keeping abreast of Japanese activity. They are impeded by language barriers, a lack of knowledge regarding Japanese technical information channels, and an ability to commit the resources needed to acquire, translate and assimilate this body of information. As a result it is found that research is duplicated, the pace of technical advance is retarded, and efforts to promote international technical cooperation are inadvertantly undermined. The greatest threat appears to be the continued insularity of U.S. industry and the attitude that the superiority of U.S. technology obviates the need to monitor Japanese progress. The Japanese, on the other hand, have long ago created dedicated organizations to follow global research and development activity systematically.

  9. Tag Content Access Control with Identity-based Key Exchange

    NASA Astrophysics Data System (ADS)

    Yan, Liang; Rong, Chunming

    2010-09-01

    Radio Frequency Identification (RFID) technology that used to identify objects and users has been applied to many applications such retail and supply chain recently. How to prevent tag content from unauthorized readout is a core problem of RFID privacy issues. Hash-lock access control protocol can make tag to release its content only to reader who knows the secret key shared between them. However, in order to get this shared secret key required by this protocol, reader needs to communicate with a back end database. In this paper, we propose to use identity-based secret key exchange approach to generate the secret key required for hash-lock access control protocol. With this approach, not only back end database connection is not needed anymore, but also tag cloning problem can be eliminated at the same time.

  10. [Technical guideline for human rabies prevention and control (2016)].

    PubMed

    Zhou, H; Li, Y; Chen, R F; Tao, X Y; Yu, P C; Cao, S C; Li, L; Chen, Z H; Zhu, W Y; Yin, W W; Li, Y H; Wang, C L; Yu, H J

    2016-02-01

    In order to promote the prevention and control programs on rabies in our country, to regulate the prevention and disposition of rabies and to reduce the deaths caused by rabies, the Chinese Center for Disease Control and Prevention has organized a panel of experts, in the reference with Guidelines issued by WHO, American Advisory Committee on Immunization Practices, and the latest research progress from home and abroad, and compiled this document-"Technical Guidelines for Human Rabies Prevention and Control (2016)". The Guidelines conducted a systematic review on the etiology, clinical characteristics, laboratory diagnosis, epidemiology of rabies and provided evidence on varieties, mechanisms, effects, side-effects and security of rabies vaccine, as well as on other preparations on passive immunity of its kind, on methods related to prevention and disposition of exposure etc, finally to have come up with the recommendation on the above mentioned various techniques. The guidelines will be used by staff working on prevention and control of rabies from the Center for Disease Control and Prevention at all levels, from the departments of outpatient and divisions of infection and emergency control in all the medical institutions. The guideline will be updated and revised, following the research progress from home and abroad.

  11. Retrograde exchange of heavily encrusted ureteric stents via the ileal conduit: a technical report.

    PubMed

    Tapping, Charles Ross; Boardman, Phil

    2014-02-01

    We describe two cases of retrograde ureteric stent exchange of heavily encrusted ureteric stents (JJ) via tortuous ileal conduits. The blocked ureteric stents were snared from inside the conduit so they could be accessed and a wire inserted. The lumens of the stents were unblocked with a wire but the stents could not be withdrawn due to heavy encrustation of the ureteric stent in the renal pelvis. A stiff wire was inserted to provide support and a 9 French peel away sheath was used to remove the encrustations allowing the stents to be withdrawn and exchanged. This is a safe and successful technique allowing ureteric stents to be removed when heavily encrusted. © 2013 The Royal Australian and New Zealand College of Radiologists.

  12. Data Exchange Format for Biological Pathway Databases (BioPAX) Workshop - Final Technical Report

    SciTech Connect

    Chris Sander, PhD

    2004-07-28

    In June 2003, the Department of Energy (DOE) allocated funds in support of the development of A Data Exchange Format for Biological Pathway Databases (BioPAX). The primary objective of the BioPAX initiative (http://www.biopax.org) is the development of a single, consensus-based standard for a data exchange format for biological pathway databases that can be widely adopted in a timely manner as a strategy for the interchange of biological pathway data in the life science community. BioPAX Level 1, Version 1.0, released July 2004, supports metabolic pathway data and is initially supported by the BioCyc and WIT databases. This work was developed during community led workshops that were significantly funded by this grant. Subsequent releases of BioPAX will add support for protein-protein interactions, signal transduction pathways, genetic interactions, and other pathway data types.

  13. Technical assessment of the Office of Industrial Programs' Advanced Heat Exchanger Program

    SciTech Connect

    Rinker, F.G.; Bergles, A.E.; Marciniak, T.J.; Batman, J.

    1987-02-01

    The DOE's AHX Program is an integral part of the OIP's Waste Heat Recovery Program whose goals are to increase the end-use energy efficiency of industry and agricultural operations, and to expand the energy options for manufacturing processes by providing technologies which use various fuels including coal, renewables, oil, and natural gas. The OIP and PNL convened a panel of industry experts to conduct a technical assessment of OIP's AHX program. This report documents the results of the panel's assessment.

  14. Factors controlling sulfur gas exchange in Sphagnum-dominated wetlands

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni; Hines, Mark E.; Bayley, Suzanne E.

    1992-01-01

    Atmosphere-peatland exchange of reduced sulfur gases was determined seasonally in fen in NH, and in an artificially-acidified fen at the Experimental Lakes Area (ELA) in Canada. Dimethyl sulfide (DMS) dominated gas fluxes at rates as high as 400 nmol/m(sup -2)hr(sup -1). DMS fluxes measured using enclosures were much higher than those calculated using a stagnant-film model, suggesting that Sphagnum regulated efflux. Temperature controlled diel and seasonal variability in DMS emissions. Use of differing enclosure techniques indicated that vegetated peatlands consume atmospheric carbonyl sulfide. Sulfate amendments caused DMS and methane thiol concentrations in near-surface pore waters to increase rapidly, but fluxes of these gases to the atmosphere were not affected. However, emission data from sites experiencing large differences in rates of sulfate deposition from the atmosphere suggested that chronic elevated sulfate inputs enhance DMS emissions from northern wetlands.

  15. The technical analysis of the stock exchange and physics: Japanese candlesticks for solar activity

    NASA Astrophysics Data System (ADS)

    Dineva, C.; Atanasov, V.

    2013-09-01

    In this article, we use the Japanese candlesticks, a method popular in the technical analysis of the Stock/Forex markets and apply it to a variable in physics-the solar activity. This method is invented and used exclusively for economic analysis and its application to a physical problem produced unexpected results. We found that the Japanese candlesticks are convenient tool in the analysis of the variables in the physics of the Sun. Based on our observations, we differentiated a new cycle in the solar activity.

  16. A Controlled Environment System For Measuring Plant-Atmosphere Gas Exchange

    Treesearch

    James M. Brown

    1975-01-01

    Describes an inexpensive, efficient system for measuring plant-atmosphere gas exchange. Designed to measure transpiration from potted tree seedlings, it is readily adaptable for measuring other gas exchanges or gas exchange by plant parts. Light level, air and root temperature can be precisely controlled at minimum cost.

  17. 77 FR 30516 - Tribally Controlled Postsecondary Career and Technical Institutions Program; Final Waivers and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ... Tribally Controlled Postsecondary Career and Technical Institutions Program; Final Waivers and Extension of... Postsecondary Career and Technical Institutions Program Catalog of Federal Domestic Assistance (CFDA) Number: 84... Postsecondary Career and Technical Institutions Program (TCPCTIP), the Secretary waives 34 CFR 75.250 and...

  18. Vitrification of ion-exchange (IEX) resins: Advantages and technical challenges

    SciTech Connect

    Jantzen, C.M.; Peeler, D.K.; Cicero, C.A.

    1995-12-31

    Technologies are being developed by the US Department of Energy`s (DOE) Savannah River Site (SRS) in conjunction with the Electric Power Research Institute (EPRI) and the commercial sector to convert low-level radioactive ion exchange (IEX) resin wastes from the nuclear utilities to solid stabilized waste forms for permanent disposal. One of the alternative waste stabilization technologies is vitrification of the resin into glass. Wastes can be vitrified at elevated temperatures by thermal treatment. One alternative thermal treatment is conventional Joule heated melting. Vitrification of wastes into glass is an attractive option because it atomistically bonds both hazardous and radioactive species in the glass structure, and volume reduces the wastes by 70-80%. The large volume reductions allow for large associated savings in disposal and/or long term storage costs.

  19. Research on What the International Exchange and Communication of Scientific and Technical Information Should Be

    NASA Astrophysics Data System (ADS)

    Murakami, Masakazu; Ashizaki, Tatsuo

    The Japanese scientific and technological information amounts to about 20% of the worldwide occurrence. According to the questionnaires about 70% of the respondants abroad experienced the use of literature written by Japanese within two months back from the date of answering. Japan is highly paid attention in a sense that she follows U.S. who is a leader in scientific and technological fields. Nevertherless only 5% of the total Japanese information has been introduced in major journals and international conferences of western world. Even information vendors have not provided information abroad actively. On the other hand it is necessary not only to provide information but also to promote mutual exchange of human resources concerning Southeast Asian countries. Considering the result of this questionnaires and trend in technology development the authors made the report on what international distribution of scientific and technological information should be. The outline of this report is described.

  20. Newly available technologies present expanding opportunities for scientific and technical information exchange

    NASA Technical Reports Server (NTRS)

    Tolzman, Jean M.

    1993-01-01

    The potential for expanded communication among researchers, scholars, and students is supported by growth in the capabilities for electronic communication as well as expanding access to various forms of electronic interchange and computing capabilities. Increased possibilities for information exchange, collegial dialogue, collaboration, and access to remote resources exist as high-speed networks, increasingly powerful workstations, and large, multi-user computational facilities are more frequently linked and more commonly available. Numerous writers speak of the telecommunications revolution and its impact on the development and dissemination of knowledge and learning. One author offers the phrase 'Scholarly skywriting' to represent a new form of scientific communication that he envisions using electronic networks. In the United States (U.S.), researchers associated with the National Science Foundation (NSF) are exploring 'nationwide collaboratories' and 'digital collaboration.' Research supported by the U.S. National Aeronautics and Space Administration (NASA) points to a future where workstations with built-in audio, video monitors, and screen sharing protocols are used to support collaborations with colleagues located throughout the world. Instruments and sensors located worldwide will produce data streams that will be brought together, analyzed, and distributed as new findings. Researchers will have access to machines that can supply domain-specific information in addition to locator and directory assistance. New forms of electronic journals will emerge and provide opportunities for researchers and scientists to exchange information electronically and interactively in a range of structures and formats. Ultimately, the wide-scale use of these technologies in the dissemination of research results and the stimulation of collegial dialogue will change the way we represent and express our knowledge of the world. A new paradigm will evolve--perhaps a truly worldwide

  1. Newly available technologies present expanding opportunities for scientific and technical information exchange

    NASA Technical Reports Server (NTRS)

    Tolzman, Jean M.

    1993-01-01

    The potential for expanded communication among researchers, scholars, and students is supported by growth in the capabilities for electronic communication as well as expanding access to various forms of electronic interchange and computing capabilities. Increased possibilities for information exchange, collegial dialogue, collaboration, and access to remote resources exist as high-speed networks, increasingly powerful workstations, and large, multi-user computational facilities are more frequently linked and more commonly available. Numerous writers speak of the telecommunications revolution and its impact on the development and dissemination of knowledge and learning. One author offers the phrase 'Scholarly skywriting' to represent a new form of scientific communication that he envisions using electronic networks. In the United States (U.S.), researchers associated with the National Science Foundation (NSF) are exploring 'nationwide collaboratories' and 'digital collaboration.' Research supported by the U.S. National Aeronautics and Space Administration (NASA) points to a future where workstations with built-in audio, video monitors, and screen sharing protocols are used to support collaborations with colleagues located throughout the world. Instruments and sensors located worldwide will produce data streams that will be brought together, analyzed, and distributed as new findings. Researchers will have access to machines that can supply domain-specific information in addition to locator and directory assistance. New forms of electronic journals will emerge and provide opportunities for researchers and scientists to exchange information electronically and interactively in a range of structures and formats. Ultimately, the wide-scale use of these technologies in the dissemination of research results and the stimulation of collegial dialogue will change the way we represent and express our knowledge of the world. A new paradigm will evolve--perhaps a truly worldwide

  2. Mutual Exchange in the Scientific Library and Technical Information Center Fields; A Report from the Special Libraries Association Delegation to the Soviet Union 1966.

    ERIC Educational Resources Information Center

    Binnington, John P., Ed.

    Articles included in this document are: (1) The Backgrounds of the Exchanges, by John P. Binnington, (2) Structure of the Soviet Scientific Information System, by Winifred Sewell, (3) Standards, Patents and Technical Reports, by Frank E. McKenna, (4) The Flow of Information to Users, by William S. Budington, (5) Research in Libraries and…

  3. Geomorphic controls on hyporheic exchange flow in mountain streams.

    Treesearch

    T. Kasahara; S.M. Wondzell

    2003-01-01

    Hyporheic exchange flows were simulated using MODFLOW and MODPATH to estimate relative effects of channel morphologic features on the extent of the hyporheic zone, on hyporheic exchange flow, and on the residence time of stream water in the hyporheic zone. Four stream reaches were compared in order to examine the influence of stream size and channel constraint. Within...

  4. Climate control of terrestrial carbon exchange across biomes and continents

    Treesearch

    Chuixiang Yi; Daniel Ricciuto; Runze Li; John Wolbeck; Xiyan Xu; Mats Nilsson; John Frank; William J. Massman

    2010-01-01

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO2 exchange with the atmosphere across biomes...

  5. Newly available technologies present expanding opportunities for scientific and technical information exchange

    NASA Technical Reports Server (NTRS)

    Tolzman, Jean M.

    1993-01-01

    The potential for expanded communication among researchers, scholars, and students is supported by growth in the capabilities for electronic communication as well as expanding access to various forms of electronic interchange and computing capabilities. Research supported by the National Aeronautics and Space Administration points to a future where workstations with audio and video monitors and screen-sharing protocols are used to support collaborations with colleagues located throughout the world. Instruments and sensors all over the world will produce data streams that will be brought together and analyzed to produce new findings, which in turn can be distributed electronically. New forms of electronic journals will emerge and provide opportunities for researchers and scientists to electronically and interactively exchange information in a wide range of structures and formats. Ultimately, the wide-scale use of these technologies in the dissemination of research results and the stimulation of collegial dialogue will change the way we represent and express our knowledge of the world. A new paradigm will evolve-perhaps a truly worldwide 'invisible college'.

  6. Newly available technologies present expanding opportunities for scientific and technical information exchange

    NASA Astrophysics Data System (ADS)

    Tolzman, Jean M.

    1993-03-01

    The potential for expanded communication among researchers, scholars, and students is supported by growth in the capabilities for electronic communication as well as expanding access to various forms of electronic interchange and computing capabilities. Research supported by the National Aeronautics and Space Administration points to a future where workstations with audio and video monitors and screen-sharing protocols are used to support collaborations with colleagues located throughout the world. Instruments and sensors all over the world will produce data streams that will be brought together and analyzed to produce new findings, which in turn can be distributed electronically. New forms of electronic journals will emerge and provide opportunities for researchers and scientists to electronically and interactively exchange information in a wide range of structures and formats. Ultimately, the wide-scale use of these technologies in the dissemination of research results and the stimulation of collegial dialogue will change the way we represent and express our knowledge of the world. A new paradigm will evolve-perhaps a truly worldwide 'invisible college'.

  7. Angular dependence of exchange bias and magnetization reversal controlled by electric-field-induced competing anisotropies

    NASA Astrophysics Data System (ADS)

    Zhao, Yonggang; Chen, Aitian; Li, Peisen; Zhang, Xu; Peng, Renci; Huang, Haoliang; Zou, Lvkuan; Zheng, Xiaoli; Zhang, Sen; Miao, Peixian; Lu, Yalin; Cai, Jian; Nan, Ce-Wen

    Combination of exchange-biased systems and FE materials gives a new avenue to study angular dependence of exchange bias and achieve reversible electric-field-controlled magnetization reversal. We study the angular dependence of electric-field-controlled exchange bias and magnetization reversal in CoFeB/IrMn/Pb(Mg1/3Nb2/3)0.7 Ti0.3O3. It is demonstrated that the ratio of the exchange-coupled unidirectional anisotropy and the uniaxial anisotropy of the FM layer, as well as their relative orientation can be dramatically and continuously tuned via electric fields. Simulations confirm that the electric-field-controlled exchange bias originates from the competition between the uniaxial anisotropy induced by the piezostrain and the exchange-coupled unidirectional anisotropy. Moreover, electric-field-controlled magnetization reversal was realized at zero magnetic field.

  8. Physiological parameters controlling plant-atmosphere ammonia exchange

    NASA Astrophysics Data System (ADS)

    Schjoerring, Jan K.; Husted, Søren; Mattsson, Marie

    Recent advances in characterizing the influence of different physiological and environmental parameters on NH 3 exchange between plants and the atmosphere are presented. A central parameter in controlling the rate and direction of NH 3 fluxes is the NH 3 compensation point. It may vary from below 1 to over 20 nmol NH 3 mol -1 air. High compensation points seem to be a result of high tissue N status, rapid absorption of NH +4 from the root medium and/or low activity of glutamine synthetase, a key enzyme in NH +4 assimilation. These conditions cause the NH +4 concentration in leaf apoplast and leaf cells to increase. The NH 3 compensation point also depends on plant developmental stage with peaks in NH 3 emission related to leaf senescence and N remobilization. The leaf temperature has a profound influence on the NH 3 compensation point: an increase in temperature from 15 to 30°C may cause a plant to switch from being a strong sink for atmospheric NH 3 to being a significant NH 3 source. Stomatal conductance for NH 3 relative to that of water vapour increases with tissue N status and with leaf senescence. At a given leaf temperature, the NH 3 compensation point can be successfully predicted on basis of the pH and NH +4 concentration in the apoplast of the mesophyll cells.

  9. Revealing controllable nanowire transformation through cationic exchange for RRAM application.

    PubMed

    Huang, Chun-Wei; Chen, Jui-Yuan; Chiu, Chung-Hua; Wu, Wen-Wei

    2014-05-14

    One dimensional metal oxide nanostructures have attracted much attention owing to their fascinating functional properties. Among them, piezoelectricity and photocatalysts along with their related materials have stirred significant interests and widespread studies in recent years. In this work, we successfully transformed piezoelectric ZnO into photocatalytic TiO2 and formed TiO2/ZnO axial heterostructure nanowires with flat interfaces by solid to solid cationic exchange reactions in high vacuum (approximately 10(-8) Torr) transmission electron microscope (TEM). Kinetic behavior of the single crystalline TiO2 was systematically analyzed. The nanoscale growth rate of TiO2 has been measured using in situ TEM videos. On the basis of the rate, we can control the dimensions of the axial-nanoheterostructure. In addition, the unique Pt/ ZnO / TiO2/ ZnO /Pt heterostructures with complementary resistive switching (CRS) characteristics were designed to solve the important issue of sneak-peak current. The resistive switching behavior was attributed to the migration of oxygen and TiO2 layer served as reservoir, which was confirmed by energy dispersive spectrometry (EDS) analysis. This study not only supplied a distinct method to explore the transformation mechanisms but also exhibited the potential application of ZnO/TiO2 heterostructure in nanoscale crossbar array resistive random-access memory (RRAM).

  10. Vibration of a flexible spacecraft with momentum exchange controllers

    NASA Technical Reports Server (NTRS)

    Canavin, J. R.

    1976-01-01

    Floating reference frames were investigated in order to allow first order vibration analysis in the presence of large system rotations. When the deformations of an elastic continuum are expanded in terms of the free-free modes of an unconstrained system, the rigid body modes are found to be fixed relative to the Tisserand frame, with respect to which the relative momentum is zero. The proof presented for this is based on the orthogonality condition for modes with distinct natural frequencies. This result also guarantees the independence of coordinates for all modes with nonzero natural frequencies. A Modified Tisserand Constraint is introduced in order to define a floating reference frame with similar properties for an elastic body which contains a spinning rotor. Finite element equations of motion are derived for a completely flexible spacecraft with momentum exchange controllers, using a Modified Tisserand Frame. The deformable systems covered in this application are assumed to undergo only small rotations, and therefore the rotor torques must formally be small, although in engineering applications it may be possible to relax this constraint. A modal analysis is performed for the system and the resulting set of equations is reduced in number by a truncation procedure for more efficient system simulation.

  11. Strain-mediated multiferroic control of spontaneous exchange bias in Ni-NiO heterostructures

    NASA Astrophysics Data System (ADS)

    Domann, John P.; Sun, Wei-Yang; Schelhas, Laura T.; Carman, Greg P.

    2016-10-01

    This paper presents the measurement of strain-mediated multiferroic control of spontaneous exchange bias (SEB) in magnetostrictive nickel/nickel oxide (Ni/NiO) bilayers on ferroelectric lead magnesium niobate-lead titanate (PMN-PT). Electric field control of a positive to negative exchange bias shift was measured, with an overall shift of 40.5 Oe, corresponding to a 325% change. Observed changes in coercivity are also reported and provide insight into the role of competing anisotropies in these structures. The findings in this paper provide evidence that magnetoelastic anisotropy can be utilized to control spontaneous exchange bias (SEB). This control of SEB is accomplished by modifying a bulk anisotropy (magnetoelasticity) that adjusts the mobility of interfacial anti-ferromagnetic spins and, therefore, the magnitude of the exchange bias. The demonstrated magnetoelastic control of exchange bias provides a useful tool in the creation of future magnetoelectric devices.

  12. Chromosome aberrations and sister-chromatid exchanges induced by technical grade toluene diisocyanate and methylenediphenyl diisocyanate in cultured human lymphocytes.

    PubMed

    Mäki-Paakkanen, J; Norppa, H

    1987-03-01

    Technical-grade toluene diisocyanate (TDI; 80% 2,4-isomer and 20% 2,6-isomer) and 4,4'-methyl-enediphenyl diisocyanate (MDI; about 45% MDI, 25% 4,4'-methylenediphenyl triisocyanate and 30% unspecified compounds of higher molecular weight), used as hardeners in the production of polyurethane, induced chromosome aberrations after a 24 h treatment in the absence of metabolic activation in human whole-blood lymphocyte cultures, MDI at all doses tested (0.54-4.30 microliter/ml) and TDI (0.019-0.150 microliter/ml) at the highest two doses (0.075 and 0.150 microliter/ml). In the presence of rat liver S9 mix (1.5 h treatment), both mixtures significantly increased aberrations at only one of the doses used, MDI at the highest dose (4.30 microliter/ml) and TDI at the second highest dose (0.038 microliter/ml). MDI also marginally increased sister-chromatid exchanges at the highest dose available (2.17 microliter/ml) with and without (48 h treatment) S9 mix. On addition to culture medium, both TDI and MDI formed polymers, which were seen as small particles on the microscopic slides. At high doses the presence of these polymers made metaphase analysis impossible.

  13. Local pulmonary blood flow: control and gas exchange.

    PubMed

    Sheehan, D W; Farhi, L E

    1993-10-01

    We studied the local response of the pulmonary vasculature to combined changes in alveolar PO2 and PCO2 in the right apical lobe (RAL) of six conscious sheep. That lobe inspired an O2-CO2-N2 mixture adjusted to produce one of 12 alveolar gas compositions: end-tidal PCO2 (PETCO2) of 40, 50, and 60 Torr, each coupled with end-tidal PO2 (PETO2) of 100, 75, 50, and 25 Torr. In addition, at each of the four PETO2, the inspired CO2 was set to 0 and PETCO2 was allowed to vary as RAL perfusion changed. The remainder of the lung, which served as control (CL) inspired air. Fraction of the total pulmonary blood flow going to the RAL (%QRAL) was obtained by comparing the methane elimination from the RAL to that of the whole lung, and expressed as a percentage of that fraction at PETCO2 = 40, PETO2 = 100. Cardiac output, pulmonary vascular pressures, and CL gas tensions were unaffected or only minimally affected by changes in RAL gas composition. A drop in PO2 from 100 to 50 Torr decreased local blood flow by 60% in normocapnia and by 66% at a PCO2 of 60. At all levels of oxygenation, an increase in PCO2 from 40 to 60 reduced QRAL by nearly 50%. With these stimulus-response data, we developed a model of gas exchange, which takes into account the effects of test segment size on blood flow diversion. This model predicts that: (1) when the ventilation to one compartment of a two compartment lung is progressively decreased, PAO2 remains above 60 Torr for up to 60% reductions in alveolar ventilation, irrespective of compartment size; (2) the decrease in PAO2 that occurs at altitude is accompanied by a drop in PACO2 that limits the decrease in conductance and minimizes the pulmonary hypertension; and (3) as we stand, local blood flow control by the alveolar gas tensions halves the alveolar-arterial PO2 and PCO2 differences imposed by gravity.

  14. Perspectives of voltage control for magnetic exchange bias in multiferroic heterostructures

    NASA Astrophysics Data System (ADS)

    Yang, Q.; Zhou, Z.; Sun, N. X.; Liu, M.

    2017-04-01

    Exchange bias, as an internal magnetic bias induced by a ferromagnetic-antiferromagnetic exchange coupling, is extremely important in many magnetic applications such as memories, sensors and other devices. Voltage control of exchange bias in multiferroics provides an energy-efficient way to achieve a rapidly 180° deterministic switching of magnetization, which has been considered as a key challenge in realizing next generation of fast, compact and ultra-low power magnetoelectric memories and sensors. Additionally, exchange bias can enhance dynamic magnetoelectric coupling strength in an external-field-free manner. In this paper, we provide a perspective on voltage control of exchange bias in different multiferroic heterostructures. Brief mechanization and related experiments are discussed as well as future trend and challenges that can be overcome by electrically tuning of exchange bias in state-of-the-art magnetoelectric devices.

  15. Application of owner technical management in hydraulic machinery and electrical equipment investment target control

    NASA Astrophysics Data System (ADS)

    Luo, H.

    2012-11-01

    Using technical means in investment target control is an effective method to improve investment benefit of a construction project. Take the practice of construction and management in hydropower station as an example, the investment and management need of the owner is put forward through the investment target decision-making process of electromechanical equipment. Owner technical management in the specific application measures and effects of investment target control was discussed in the paper, and the revelation in investment target control application of owner technical management was also summarized. The paper is aimed to provide a useful reference for the investment target control work in the construction of electromechanical equipment.

  16. Phenological control over ecosystem-atmosphere carbon exchange (Invited)

    NASA Astrophysics Data System (ADS)

    Monson, R. K.; Moore, D. J.; Scott-Denton, L.; Burns, S. P.

    2010-12-01

    Our understanding of ecosystem-atmosphere carbon fluxes has been improved over the past decade in large part due to the maturation of observational records from networks of flux towers and the development of model-data assimilation techniques from which insight into carbon cycle processes can be extracted. Some of the earliest analyses of the observation record revealed that interannual phenological variation in forest ecosystems has a significant influence on the annual cumulative net rate of CO2 uptake from the atmosphere. In winter-deciduous forest ecosystems, phenological variability in the timing of bud break in the spring, and the early-season rate at which the forest reaches its seasonal maximum leaf area index, have large effects on the ultimate annual sum for net ecosystem CO2 exchange (NEE). In snow-controlled evergreen forests, the timing at which snow melt or soil thaw occurs, and liquid water becomes available to drive diurnal increases in stomatal conductance, the spring 'phenological switch-on' can be abrupt and the capacity for the forest to reach its seasonal maximum NEE can occur within a few days. The relatively high sensitivity of ecosystem carbon budgets to variability in phenology renders it difficult to accurately model system dynamics, especially for evergreen forests. Recent model-data assimilation studies have found large errors in the ability of the models to replicate observations of NEE at the seasonal-to-annual time scales, in large part due to inadequacies in how they capture spring and fall phenology thresholds and early- and late-season dynamics in the state of the photosynthetic apparatus. In our own studies of interannual variation in NEE in the evergreen subalpine forest at Niwot Ridge, Colorado, we have not been able to accurately represent spring phenology dynamics and their influence on annual NEE using the Simple Evapotranspiration and Net Photosynthesis (SIPNET) model without explicit consideration of snowmelt dynamics. In

  17. Direct-hydrogen-fueled proton-exchange-membrane (PEM) fuel cell system for transportation applications. Quarterly technical progress report No. 4, April 1, 1995--June 30, 1995

    SciTech Connect

    Oei, D.

    1995-08-03

    This is the fourth Technical Progress Report for DOE Contract No. DE-AC02-94CE50389 awarded to Ford Motor Company on July 1, 1994. The overall objective of this contract is to advance the Proton-Exchange-Membrane (PEM) fuel cell technology for automotive applications. Specifically, the objectives resulting from this contract are to: (1) Develop and demonstrate on a laboratory propulsion system within 2-1/2 years a fully functional PEM Fuel Cell Power System (including fuel cell peripherals, peak power augmentation and controls). This propulsion system will achieve, or will be shown to have the growth potential to achieve, the weights, volumes, and production costs which are competitive with those same attributes of equivalently performing internal combustion engine propulsion systems; (2) Select and demonstrate a baseline onboard hydrogen storage method with acceptable weight, volume, cost, and safety features and analyze future alternatives; and (3) Analyze the hydrogen infrastructure components to ensure that hydrogen can be safely supplied to vehicles at geographically widespread convenient sites and at prices which are less than current gasoline prices per vehicle-mile; (4) Identify any future R&D needs for a fully integrated vehicle and for achieving the system cost and performance goals.

  18. 47 CFR 68.317 - Hearing aid compatibility volume control: technical standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... National Standards Institute (ANSI) Standard ANSI/EIA-470-A-1987 and paragraph 4.3.2 of ANSI/EIA/TIA-579...: technical standards. 68.317 Section 68.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... for Terminal Equipment Approval § 68.317 Hearing aid compatibility volume control: technical standards...

  19. 47 CFR 68.317 - Hearing aid compatibility volume control: technical standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... National Standards Institute (ANSI) Standard ANSI/EIA-470-A-1987 and paragraph 4.3.2 of ANSI/EIA/TIA-579...: technical standards. 68.317 Section 68.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... for Terminal Equipment Approval § 68.317 Hearing aid compatibility volume control: technical standards...

  20. Leo Szilard Lectureship Award: Science Matters - Technical Dimensions of Arms Control and Non-Proliferation Agreements

    NASA Astrophysics Data System (ADS)

    Timbie, James

    2017-01-01

    Agreements to reduce nuclear arms and prevent proliferation of nuclear weapons are technical as well as political documents. They must be both technically sound and politically acceptable. This presentation illustrates technical aspects of arms control and non-proliferation agreements, with examples from SALT I, INF, the HEU Agreement, START, and the Iran nuclear negotiations, drawing on 44 years of personal experience in the negotiation of these agreements. The lecture is designed to convey an appreciation of the role that individuals with technical training can play in diplomatic efforts to reduce nuclear forces and prevent nuclear proliferation.

  1. Condensing heat exchanger microbial growth and control study-phase 2

    SciTech Connect

    Marsh, R.W.; Caron, M.E.; Metselaar, C.; Steele, J.

    1993-12-31

    The Space Station Temperature and Humidity Control Condensing Heat Exchangers will be utilized to collect and remove atmospheric water vapor generated by the metabolic and hygienic activity of crew members. The porous hydrophillic coating within the heat exchangers will always be wet. Cabin air will continuously flow through the heat exchangers during system operation which makes them a potential site for microbial colonization. This paper summarizes the findings form an ongoing study which evaluates biofilm formation on wet hydrophilic coated panels compared to panels to which microbial control measures have have been applied. The control measures evaluated are an antimicrobial agent within the coating and periodic drying.

  2. Web-based technical assistance and training to promote community tobacco control policy change.

    PubMed

    Young, Walter F; Montgomery, Debbie; Nycum, Colleen; Burns-Martin, Lavon; Buller, David B

    2006-01-01

    In 1998 the tobacco industry was released of claims that provided monetary relief for states. A significant expansion of tobacco control activity in many states created a need to develop local capacity. Technical assistance and training for new and experienced staff became a significant challenge for tobacco control leadership. In Colorado, this challenge was addressed in part through the development of a technical assistance and training Web site designed for local tobacco control staff and coalition members. Researchers, technical Web site development specialists, state health agency, and state tobacco control coalition staff collaborated to develop, promote, and test the efficacy of this Web site. The work group embodied a range of skills including tobacco control, Web site technical development, marketing, training, and project management. Persistent marketing, updating of Web site content, and institutionalizing it as a principal source of information and training were key to use by community coalition members.

  3. Technical Complications during Veno-Venous Extracorporeal Membrane Oxygenation and Their Relevance Predicting a System-Exchange – Retrospective Analysis of 265 Cases

    PubMed Central

    Lubnow, Matthias; Philipp, Alois; Foltan, Maik; Bull Enger, Tone; Lunz, Dirk; Bein, Thomas; Haneya, Assad; Schmid, Christof; Riegger, Günter; Müller, Thomas; Lehle, Karla

    2014-01-01

    Objectives Technical complications are a known hazard in veno-venous extracorporeal membrane oxygenation (vvECMO). Identifying these complications and predictive factors indicating a developing system-exchange was the goal of the study. Methods Retrospective study on prospectively collected data of technical complications including 265 adult patients (Regensburg ECMO Registry, 2009-2013) with acute respiratory failure treated with vvECMO. Alterations in blood flow resistance, gas transfer capability, hemolysis, coagulation and hemostasis parameters were evaluated in conjunction with a system-exchange in all patients with at least one exchange (n = 83). Results Values presented as median (interquartile range). Patient age was 50(36–60) years, the SOFA score 11(8–14.3) and the Murray lung injury Score 3.33(3.3–3.7). Cumulative ECMO support time 3411 days, 9(6–15) days per patient. Mechanical failure of the blood pump (n = 5), MO (n = 2) or cannula (n = 1) accounted for 10% of the exchanges. Acute clot formation within the pump head (visible clots, increase in plasma free hemoglobin (frHb), serum lactate dehydrogenase (LDH), n = 13) and MO (increase in pressure drop across the MO, n = 16) required an urgent system-exchange, of which nearly 50% could be foreseen by measuring the parameters mentioned below. Reasons for an elective system-exchange were worsening of gas transfer capability (n = 10) and device-related coagulation disorders (n = 32), either local fibrinolysis in the MO due to clot formation (increased D-dimers [DD]), decreased platelet count; n = 24), or device-induced hyperfibrinolysis (increased DD, decreased fibrinogen [FG], decreased platelet count, diffuse bleeding tendency; n = 8), which could be reversed after system-exchange. Four MOs were exchanged due to suspicion of infection. Conclusions The majority of ECMO system-exchanges could be predicted by regular inspection of the complete ECMO circuit

  4. The pebble GTP exchange factor and the control of cytokinesis.

    PubMed

    O'Keefe, L; Somers, W G; Harley, A; Saint, R

    2001-12-01

    Several G proteins of the Rho family have been shown to be required for cytokinesis. The activity of these proteins is regulated by GTP exchange factors (GEFs), which stimulate GDP/GTP exchange, and by GTPase activating proteins (GAPs), which suppress activity by stimulating the intrinsic GTPase activity. The role of Rho family members during cytokinesis is likely to be determined by their spatial and temporal interactions with these factors. Here we focus on the role of the pebble (pbl) gene of Drosophila melanogaster, a RhoGEF that is required for cytokinesis. We summarise the evidence that the primary target of PBL is Rho1 and describe genetic approaches to elucidating the function of PBL and identifying other components of the PBL-activated Rho signalling pathway.

  5. Monitoring hyporheic exchanges during a dam controlled experiment

    NASA Astrophysics Data System (ADS)

    Houzé, Clémence; Varnède, Lucie; Durand, Véronique; Pessel, Marc

    2016-04-01

    Precise understanding of the hyporheic exchanges response to stream flow fluctuations remains a great challenge for many environmental and hydrological problems. Multiplication of natural stream restoration programs and anthropic structures removal highlight that a better understanding of the hydrodynamic and ecological functioning of hyporheic exchanges is critical . The objective of this field experiment was to monitor the dynamic exchanges within the hyporheic zone due to an artificial stream head variation. Various types of measurements were performed, using natural tracers and electrical resistivity tomography (ERT). The dam downstream the studied river reach was successively lowered during two days, and raised during three days, implying river heads variations of about 15cm. The studied area was equipped with CTD probes (measuring the head and the conductivity) within the river, 2 multi-depths water sampling tubes inserted up to one meter depth within the riverbed deposits and 3 ERT profiles with various electrode spacing (20 cm, 25 cm, 50 cm). During the 5 days experiment, water sampling and ERT profiles were done regularly. Estimations of the sediments hydraulic conductivity were obtained by several slug tests in plastic tubes at different depths within the streambed. First results showed that stream fluctuation leads to a rapid hyporheic response according to chloride variations between stream and riverbed sediments. Similar results between geochemical and geophysical tools were found. A decrease in stream head leads to reduce the depth of the mixing zone, as the river gaining conditions intensify. On the contrary, we observed that an increased river head tends to deepen the hyporheic exchange zone.

  6. Controlling mercury spills in laboratories with a thermometer exchange program

    SciTech Connect

    McLouth, Lawrence D.

    2002-03-25

    This paper presents a case for replacing mercury thermometers with their organic-liquid-filled counterparts. A review of liquid-in glass-thermometers is given. In addition, a brief summary of mercury's health effects and exposure limits is presented. Spill cleanup methods and some lessons learned from our experience are offered as well. Finally, an overview of the mercury thermometer exchange program developed at Lawrence Berkeley National Laboratory is presented.

  7. Climate control of terrestrial carbon exchange across biomes and continents

    SciTech Connect

    Ricciuto, Daniel M; Gu, Lianhong

    2010-07-01

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO2 exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid- and high-latitudes, (2) a strong function of dryness at mid- and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45 N). The sensitivity of NEE to mean annual temperature breaks down at ~ 16 C (a threshold value of mean annual temperature), above which no further increase of CO2 uptake with temperature was observed and dryness influence overrules temperature influence.

  8. Electrically Controlled Anion Exchange Based on Polypyrrole and Carbon Nanotubes Nanocomposite for Perchlorate Removal

    SciTech Connect

    Lin, Yuehe; Cui, Xiaoli; Bontha, Jagannadha R.

    2006-06-01

    A novel and stable carbon nanotube/polypyrrole nanocomposite film has been electrosynthesized and the feasibility for removing perchlorate ion through an electrically controlled anion exchange has been evaluated.

  9. TECHNICAL GUIDANCE DOCUMENT: QUALITY ASSURANCE AND QUALITY CONTROL FOR WASTE CONTAINMENT FACILITIES

    EPA Science Inventory

    This Technical Guidance Document provides comprehensive guidance on procedures for quality assurance and quality control for waste containment facilities. The document includes a discussion of principles and concepts, compacted soil liners, soil drainage systems, geosynthetic dr...

  10. Technical management techniques for identification and control of industrial safety and pollution hazards

    NASA Technical Reports Server (NTRS)

    Campbell, R.; Dyer, M. K.; Hoard, E. G.; Little, D. G.; Taylor, A. C.

    1972-01-01

    Constructive recommendations are suggested for pollution problems from offshore energy resources industries on outer continental shelf. Technical management techniques for pollution identification and control offer possible applications to space engineering and management.

  11. TECHNICAL GUIDANCE DOCUMENT: QUALITY ASSURANCE AND QUALITY CONTROL FOR WASTE CONTAINMENT FACILITIES

    EPA Science Inventory

    This Technical Guidance Document provides comprehensive guidance on procedures for quality assurance and quality control for waste containment facilities. The document includes a discussion of principles and concepts, compacted soil liners, soil drainage systems, geosynthetic dr...

  12. Technical Highlight: Evaluation of Humidity Control Options in Hot-Humid Climate Homes

    SciTech Connect

    none,

    2011-12-01

    This technical highlight describes NREL research to analyze the indoor relative humidity in three home types in the hot-humid climate zone, and examine the impacts of various dehumidification equipment and controls.

  13. Study on the Heat-Flow Controllable Heat Exchanger-3rd report

    NASA Astrophysics Data System (ADS)

    Ishikawa, Osamu; Hamano, Masayoshi; Yanadori, Michio

    The heat-flow controllable heat exchanger for the purpose of heat recovery through the waste hot water at the bathroom and the washing room has been developed. The system is especially available at the house of cold area and the recovery heat is used to warm the suction air conducted from ventilation device. As the result of field test, it is clarified that the heat recovery rate by the system is very large. Also, the exchanger is possible to control the amount of recorery heat. Therefore, it is considered that the exchanger is applicable in the ventilation systems used the waste hot water.

  14. Regulation of cellular gas exchange, oxygen sensing, and metabolic control.

    PubMed

    Clanton, T L; Hogan, M C; Gladden, L B

    2013-07-01

    Cells must continuously monitor and couple their metabolic requirements for ATP utilization with their ability to take up O2 for mitochondrial respiration. When O2 uptake and delivery move out of homeostasis, cells have elaborate and diverse sensing and response systems to compensate. In this review, we explore the biophysics of O2 and gas diffusion in the cell, how intracellular O2 is regulated, how intracellular O2 levels are sensed and how sensing systems impact mitochondrial respiration and shifts in metabolic pathways. Particular attention is paid to how O2 affects the redox state of the cell, as well as the NO, H2S, and CO concentrations. We also explore how these agents can affect various aspects of gas exchange and activate acute signaling pathways that promote survival. Two kinds of challenges to gas exchange are also discussed in detail: when insufficient O2 is available for respiration (hypoxia) and when metabolic requirements test the limits of gas exchange (exercising skeletal muscle). This review also focuses on responses to acute hypoxia in the context of the original "unifying theory of hypoxia tolerance" as expressed by Hochachka and colleagues. It includes discourse on the regulation of mitochondrial electron transport, metabolic suppression, shifts in metabolic pathways, and recruitment of cell survival pathways preventing collapse of membrane potential and nuclear apoptosis. Regarding exercise, the issues discussed relate to the O2 sensitivity of metabolic rate, O2 kinetics in exercise, and influences of available O2 on glycolysis and lactate production. © 2013 American Physiological Society.

  15. Technical basis for implementation of remote reading capabilities for radiological control instruments at tank farms

    SciTech Connect

    PIERSON, R.M.

    1999-10-27

    This document provides the technical basis for use of remote reading capabilities with radiological control instruments at River Protection Project facilities. The purpose of this document is to evaluate applications of remote reading capabilities with Radiological Control instrumentation to allow continuous monitoring of radiation dose rates at River Protection Project (RPP) facilities. In addition this document provides a technical basis and implementing guidelines for remote monitoring of dose rates and their potential contribution to maintaining radiation exposures ALARA.

  16. Voltage Control of Exchange Bias in a Chromium Oxide Based Thin Film Heterostructure

    NASA Astrophysics Data System (ADS)

    Echtenkamp, Will; Street, Mike; Mahmood, Ather; Binek, Christian

    Controlling magnetism by electrical means is a key challenge in the field of spintronics, and electric control of exchange bias is one of the most promising routes to address this challenge. Isothermal electric control of exchange bias has been achieved near room temperature using bulk, single crystal, magnetoelectric Cr2O3. In this study the electrically-controlled exchange bias is investigated in an all thin film Cr2O3/PdCo exchange bias heterosystem where an MBE grown ferromagnetic and perpendicular anisotropic Pd/Co multilayer has been deposited on a PLD grown (0001) Cr2O3 thin film. Prototype devices are fabricated using lithography techniques. Using a process of magnetoelectric annealing, voltage control of exchange bias in Cr2O3 heterostructures is demonstrated with significant implications for scalability of ultra-low power memory and logical devices. In addition, the dependence of the exchange bias on the applied electric and magnetic fields are independently studied at 300K and isothermal voltage-controlled switching is investigated. This project was supported by SRC through CNFD, an SRC-NRI Center, by C-SPIN, part of STARnet, and by the NSF through MRSEC DMR-0820521.

  17. The control of hyperhomocysteinemia through thiol exchange mechanisms by mesna.

    PubMed

    Di Giuseppe, Danila; Priora, Raffaella; Coppo, Lucia; Ulivelli, Monica; Bartalini, Sabina; Summa, Domenico; Margaritis, Antonios; Frosali, Simona; Di Simplicio, Paolo

    2014-02-01

    In hyperhomocysteinemic patients, after reaction with homocysteine-albumin mixed disulfides (HSS-ALB), mesna (MSH) forms the mixed disulfide with Hcy (HSSM) which can be removed by renal clearance, thus reducing the plasma concentration of total homocysteine (tHcy). In order to assess the HSS-ALB dethiolation via thiol exchange reactions, the distribution of redox species of cysteine, cysteinylglycine, homocysteine and glutathione was investigated in the plasma of healthy subjects: (i) in vitro, after addition of 35 μM reduced homocysteine (HSH) to plasma for 72 h, followed by MSH addition (at the concentration range 10-600 μM) for 25 min; (ii) in vivo, after oral treatment with methionine (methionine, 200 mg/kg body weight, observation time 2-6 h). In both experiments the distribution of redox species, but not the total amount of each thiol, was modified by thiol exchange reactions of albumin and cystine, with changes thermodynamically related to the pKa values of thiols in the corresponding mixed disulfides. MSH provoked a dose-response reversal of the redox state of aged plasma, and the thiol action was confirmed by in vivo experiments. Since it was observed that the dimesna production could be detrimental for the in vivo optimization of HSSM formation, we assume that the best plasma tHcy lowering can be obtained at MSH doses producing the minimum dimesna concentration in each individual.

  18. High infection control rate and function after routine one-stage exchange for chronically infected TKA.

    PubMed

    Jenny, Jean-Yves; Barbe, Bruno; Gaudias, Jeannot; Boeri, Cyril; Argenson, Jean-Noël

    2013-01-01

    Many surgeons consider two-stage exchange the gold standard for treating chronic infection after TKA. One-stage exchange is an alternative for infection control and might provide better knee function, but the rates of infection control and levels of function are unclear. We asked whether a one-stage exchange protocol would lead to infection control rates and knee function similar to those after two-stage exchange. We followed all 47 patients with chronically infected TKAs treated with one-stage exchange between July 2004 and February 2007. We monitored for recurrence of infection and obtained Knee Society Scores. We followed patients a minimum of 3 years or until death or infection recurrence. Three of the 47 patients (6%) experienced a persistence or recurrence of the index infection with the same pathogen isolated. Three patients (6%) had control of the index infection but between 6 and 17 months experienced an infection with another pathogen. The 3-year survival rates were 87% for being free of any infection and 91% for being healed of the index infection. Twenty-five of the 45 patients (56%) had a Knee Society Score of more than 150 points. While routine one-stage exchange was not associated with a higher rate of infection recurrence failure, knee function was not improved compared to that of historical patients having two-stage exchange. One stage-exchange may be a reasonable alternative in chronically infected TKA as a more convenient approach for patients without the risks of two operations and hospitalizations and for reducing costs. The ideal one stage-exchange candidate should be identified in future studies.

  19. Controlled optical properties of water-soluble CdTe nanocrystals via anion exchange.

    PubMed

    Li, Jing; Jia, Jianguang; Lin, Yuan; Zhou, Xiaowen

    2016-02-01

    We report a study on anion exchange reaction of CdTe nanocrystals with S(2-) in aqueous solution under ambient condition. We found that the optical properties of CdTe nanocrystals can be well tuned by controlling the reaction conditions, in which the reaction temperature is crucially important. At low reaction temperature, the product nanocrystals showed blue-shifts in both absorption and PL spectra, while the photoluminescence quantum yield (PLQY) was significantly enhanced. When anion exchanges were carried out at higher reaction temperature, on the other hand, obvious red shifts in absorption and PL spectra accompanied by a fast increase followed by gradual decrease in PLQY were observed. On variation of S(2-) concentration, it was found that the overall kinetics of Te(2-) for S(2-) exchanges depends also on [S(2-)] when anion exchanges were performed at higher temperature. A possible mechanism for anion exchanges in CdTe NCs was proposed.

  20. Temperature control using a heat exchanger of a cardioplegic system in cardiopulmonary bypass model for rats.

    PubMed

    Kim, Won Gon; Choi, Se Hun; Kim, Jin Hyun

    2008-12-01

    Small animal cardiopulmonary bypass (CPB) model would be a valuable tool for investigating pathophysiological and therapeutic strategies on bypass. However, the rat CPB models have a number of technical limitations. Effective maintenance and control of core temperature by heat exchanger (HE) is among them. The purpose of this study was to confirm the effect of rectal temperature maintenance and hypothermic control using a HE of cardioplegia system in CPB model for rats. The miniature circuit consisted of a reservoir, HE, membrane oxygenator, and roller pump; the static priming volume was 40 cc. In the first stage of experiment, 10 male Sprague-Dawley rats were divided into two groups; HE group was subjected to CPB with HE from a cardioplegia system, and control group was subjected to CPB with warm water circulating around the reservoir. Partial CPB was conducted at a flow rate of 40 mg/kg/min for 20 min after venous cannulation (via the internal jugular vein) and arterial cannulation (via the femoral artery). Rectal temperature was measured after anesthetic induction, after cannulation, 5, 10, 15, and 20 min after CPB. Arterial blood gas with hematocrit was also analyzed, 5 and 15 min after CPB. In the second stage with the same experimental setting, rectal temperatures were lowered in 10 rats to the target temperature of 32 degrees C. After reaching the target temperature, animals were rewarmed. Rectal temperature was measured after cannulation, 5, 10, 15, 20, 25, and 30 min after CPB. Arterial blood gas with hematocrit was also analyzed, 5 and 15 min after CPB. Rectal temperature change differed between the two groups (P < 0.01). The temperatures of the HE group were well maintained during CPB, whereas the control group was under progressive hypothermia. Rectal temperature 20 min after CPB was 36.16 +/- 0.32 degrees C in the HE group and 34.22 +/- 0.36 degrees C in the control group. In the second set of experiments, the hypothermia targeted (32 degrees C) was

  1. Spin-controlled negative magnetoresistance resulting from exchange interactions

    NASA Astrophysics Data System (ADS)

    Agrinskaya, N. V.; Kozub, V. I.; Mikhailin, N. Yu.; Shamshur, D. V.

    2017-04-01

    We studied conductivity of AlGaAs-GaAs quantum well structures (where centers of the wells were doped by Be) at temperatures higher than 4 K in magnetic fields up 10 T. Throughout all the temperature region considered the conductivity demonstrated activated behavior. At moderate magnetic fields 0.1 T < H < 1 T, we observed negative isotropic magnetoresistance, which was linear in magnetic field while for magnetic field normal with respect to the plane of the wells the magnetoresistance was positive at H > 2T. To the best of our knowledge, it was the first observation of linear negative magnetoresistance, which would be isotropic with respect to the direction of magnetic field. While the isotropic character of magnetoresistance apparently evidences role of spins, the existing theoretical considerations concerning spin effects in conductance fail to explain our experimental results. We believe that such a behavior can be attributed to spin effects supported by exchange interactions between localized states.

  2. Comparison of Advanced Distillation Control Methods, Final Technical Report

    SciTech Connect

    Dr. James B. Riggs

    2000-11-30

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selections for single-ended and dual-composition control, as well as to compare conventional and advanced control approaches. In addition, a simulator of a main fractionator was used to compare the control performance of conventional and advanced control. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that the use of dynamic simulations is required in order to identify the optimum configuration from among the nine possible choices. The optimum configurations were used to evaluate the relative control performance of conventional PI controllers, MPC (Model Predictive Control), PMBC (Process Model-Based Control), and ANN (Artificial Neural Networks) control. It was determined that MPC works best when one product is much more important than the other, while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and MPC. MPC was found to outperform conventional PI control for the main fractionator. MPC was applied to three industrial columns: one at Phillips Petroleum and two at Union Carbide. In each case, MPC was found to significantly outperform PI controls. The major advantage of the MPC controller is its ability to effectively handle a complex set of constraints and control objectives.

  3. Relaciones Culturales de Mexico: Convenios de Intercambio Cultural y Asistencia Tecnica (Mexican Cultural Relations: Cultural Exchange and Technical Assistance Agreements).

    ERIC Educational Resources Information Center

    n10 p43-83, 1971

    1971-01-01

    This document is an English-language abstract (approximately 1500 words) describing briefly Mexico's cultural relations with 23 nations with which she has cultural exchange agreements. The reasons for cultural exchange are stated, such as the belief that cultural relations promote good relations among nations. The agreements concluded between…

  4. Relaciones Culturales de Mexico: Convenios de Intercambio Cultural y Asistencia Tecnica (Mexican Cultural Relations: Cultural Exchange and Technical Assistance Agreements).

    ERIC Educational Resources Information Center

    n10 p43-83, 1971

    1971-01-01

    This document is an English-language abstract (approximately 1500 words) describing briefly Mexico's cultural relations with 23 nations with which she has cultural exchange agreements. The reasons for cultural exchange are stated, such as the belief that cultural relations promote good relations among nations. The agreements concluded between…

  5. Trading Up: Chimpanzees (Pan troglodytes) Show Self-Control Through Their Exchange Behavior

    PubMed Central

    Beran, Michael J.; Rossettie, Mattea S.; Parrish, Audrey E.

    2015-01-01

    Self-control is defined as the ability or capacity to obtain an objectively more valuable outcome rather than an objectively less valuable outcome though tolerating a longer delay or a greater effort requirement (or both) in obtaining that more valuable outcome. A number of tests have been devised to assess self-control in nonhuman animals, including exchange tasks. In this study, three chimpanzees (Pan troglodytes) participated in a delay of gratification task that required food exchange as the behavioral response that reflected self-control. The chimpanzees were offered opportunities to inhibit eating and instead exchange a currently possessed food item for a different (and sometimes better) item, often needing to exchange several food items before obtaining the highest-valued reward. We manipulated reward type, reward size, reward visibility, delay to exchange, and location of the highest-valued reward in the sequence of exchange events to compare performance within the same individuals. The chimpanzees successfully traded until obtaining the best item in most cases, although there were individual differences among participants in some variations of the test. These results support the idea that self-control is robust in chimpanzees even in contexts in which they perhaps anticipate future rewards and sustain delay of gratification until they can obtain the ultimately most-valuable item. PMID:26325355

  6. Natural convection heat exchangers for solar water heating systems. Technical progress report, May 15, 1996--July 14, 1996

    SciTech Connect

    Davidson, J.H.

    1998-06-01

    This progress report very briefly summarizes study results and includes an experimental plan developed for the fundamental study of heat transfer in thermosyphon side-arm heat exchangers. The study will investigate the influence of the Reynolds and Grashof numbers on the thermosyphon flow side of the heat exchanger, and the influence of the flow rate on the forced flow side of the heat exchanger. Detailed temperature, flow rate, and pressure data will be obtained for four, seven, and nine tube-in-shell heat exchanger designs. Correlations will be developed for the heat transfer and friction coefficients, and a semi-empirical model will be developed to predict the performance of thermosyphon heat exchangers in solar water heaters.

  7. Best practices for the use and exchange of invertebrate biological control genetic resources relevant for food and agriculture

    USDA-ARS?s Scientific Manuscript database

    Biological control is an important and environmentally preferred management option for invasive insect pests and weeds. Implementation of new international regulations governing exchange of genetic materials impacts the availability of candidate biocontrol agents, and exchange policies need to be ca...

  8. Application of horizontal spiral coil heat exchanger for volatile organic compounds (VOC) emission control.

    PubMed

    Deshpande, P M; Dawande, S D

    2013-04-01

    The petroleum products have wide range of volatility and are required to be stored in bulk. The evaporation losses are significant and it is a economic as well as environmental concern, since evaporative losses of petroleum products cause increased VOC in ambient air. Control of these losses poses a major problem for the storage tank designers. Ever rising cost of petroleum products further adds to the gravity of the problem. Condensation is one of the technologies for reducing volatile organic compounds emissions. Condensation is effected by condenser, which is basically a heat exchanger and the heat exchanger configuration plays an important role. The horizontal spiral coil heat exchanger is a promising configuration that finds an application in VOC control. This paper attempts to understand underlying causes of emissions and analyse the option of horizontal spiral coil heat exchanger as vent condenser.

  9. Angular Dependence of Exchange Bias and Magnetization Reversal Controlled by Electric-Field-Induced Competing Anisotropies.

    PubMed

    Chen, Aitian; Zhao, Yonggang; Li, Peisen; Zhang, Xu; Peng, Renci; Huang, Haoliang; Zou, Lvkuan; Zheng, Xiaoli; Zhang, Sen; Miao, Peixian; Lu, Yalin; Cai, Jianwang; Nan, Ce-Wen

    2016-01-13

    The combination of exchange-biased systems and ferroelectric materials offers a simple and effective way to investigate the angular dependence of exchange bias using one sample with electric-field-induced competing anisotropies. A reversible electric-field-controlled magnetization reversal at zero magnetic field is also realized through optimizing the anisotropy configuration, holding promising applications for ultralow power magnetoelectric devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Knowledge based system for runtime controlling of multiscale model of ion-exchange solvent extraction

    NASA Astrophysics Data System (ADS)

    Macioł, Piotr; Gotfryd, Leszek; Macioł, Andrzej

    2012-09-01

    The hereby paper concerns the issue of solution of runtime controlling of multiscale model of ion-exchange solvent extraction. It is based on cooperation of a framework applying Agile Multiscale Modeling Methodology (AM3), and the REBIT Knowledge Based System. Ion-exchange solvent extraction has been shortly introduced. Design assumptions of AM3 and theoretical basis of REBIT have been described. Designed workflows and rules for simple laminar/ turbulent flow and extraction processes have been shown.

  11. Guidelines for Controlling Environmental Tobacco Smoke in Schools. Technical Bulletin.

    ERIC Educational Resources Information Center

    Turner, Ronald W.; And Others

    Environmental tobacco smoke (ETS) is one of the most widespread and harmful indoor pollutants. This document offers guidelines for controlling ETS in schools. The harmful effects of passive smoke and the Maryland policy regarding smoking in public places are first described. Strategies to control exposure to ETS are outlined, with consideration of…

  12. Direct shape control of photoreduced nanostructures on proton exchanged ferroelectric templates

    NASA Astrophysics Data System (ADS)

    Balobaid, Laila; Craig Carville, N.; Manzo, Michele; Gallo, Katia; Rodriguez, Brian J.

    2013-01-01

    Photoreduction on a periodically proton exchanged ferroelectric crystal leads to the formation of periodic metallic nanostructures on the surface. By varying the depth of the proton exchange (PE) from 0.59 to 3.10 μm in congruent lithium niobate crystals, the width of the lateral diffusion region formed by protons diffusing under the mask layer can be controlled. The resulting deposition occurs in the PE region with the shallowest PE depth and preferentially in the lateral diffusion region for greater PE depths. PE depth-control provides a route for the fabrication of complex metallic nanostructures with controlled dimensions on chemically patterned ferroelectric templates.

  13. Using the Feature Exchange Language in the Next Generation Controller

    DTIC Science & Technology

    1990-08-01

    The following example illustrates how FEL can be used to send commands to a low-lev- el motion controller (in this case the GALIL 3-axis DMC-230).’ The...controlled the GALIL board would have to be designed with a higher level in- terface. 5.1.4. Image Processing In this section, we will describe how...user program for a set of Datacube boards is much more complex than the interface to the GALIL motion control described in the previous section

  14. Integrating Space Flight Resource Management Skills into Technical Lessons for International Space Station Flight Controller Training

    NASA Technical Reports Server (NTRS)

    Baldwin, Evelyn

    2008-01-01

    The Johnson Space Center s (JSC) International Space Station (ISS) Space Flight Resource Management (SFRM) training program is designed to teach the team skills required to be an effective flight controller. It was adapted from the SFRM training given to Shuttle flight controllers to fit the needs of a "24 hours a day/365 days a year" flight controller. More recently, the length reduction of technical training flows for ISS flight controllers impacted the number of opportunities for fully integrated team scenario based training, where most SFRM training occurred. Thus, the ISS SFRM training program is evolving yet again, using a new approach of teaching and evaluating SFRM alongside of technical materials. Because there are very few models in other industries that have successfully tied team and technical skills together, challenges are arising. Despite this, the Mission Operations Directorate of NASA s JSC is committed to implementing this integrated training approach because of the anticipated benefits.

  15. Quantifying control effort of biological and technical movements: an information-entropy-based approach.

    PubMed

    Haeufle, D F B; Günther, M; Wunner, G; Schmitt, S

    2014-01-01

    In biomechanics and biorobotics, muscles are often associated with reduced movement control effort and simplified control compared to technical actuators. This is based on evidence that the nonlinear muscle properties positively influence movement control. It is, however, open how to quantify the simplicity aspect of control effort and compare it between systems. Physical measures, such as energy consumption, stability, or jerk, have already been applied to compare biological and technical systems. Here a physical measure of control effort based on information entropy is presented. The idea is that control is simpler if a specific movement is generated with less processed sensor information, depending on the control scheme and the physical properties of the systems being compared. By calculating the Shannon information entropy of all sensor signals required for control, an information cost function can be formulated allowing the comparison of models of biological and technical control systems. Exemplarily applied to (bio-)mechanical models of hopping, the method reveals that the required information for generating hopping with a muscle driven by a simple reflex control scheme is only I=32 bits versus I=660 bits with a DC motor and a proportional differential controller. This approach to quantifying control effort captures the simplicity of a control scheme and can be used to compare completely different actuators and control approaches.

  16. Quantifying control effort of biological and technical movements: An information-entropy-based approach

    NASA Astrophysics Data System (ADS)

    Haeufle, D. F. B.; Günther, M.; Wunner, G.; Schmitt, S.

    2014-01-01

    In biomechanics and biorobotics, muscles are often associated with reduced movement control effort and simplified control compared to technical actuators. This is based on evidence that the nonlinear muscle properties positively influence movement control. It is, however, open how to quantify the simplicity aspect of control effort and compare it between systems. Physical measures, such as energy consumption, stability, or jerk, have already been applied to compare biological and technical systems. Here a physical measure of control effort based on information entropy is presented. The idea is that control is simpler if a specific movement is generated with less processed sensor information, depending on the control scheme and the physical properties of the systems being compared. By calculating the Shannon information entropy of all sensor signals required for control, an information cost function can be formulated allowing the comparison of models of biological and technical control systems. Exemplarily applied to (bio-)mechanical models of hopping, the method reveals that the required information for generating hopping with a muscle driven by a simple reflex control scheme is only I =32bits versus I =660bits with a DC motor and a proportional differential controller. This approach to quantifying control effort captures the simplicity of a control scheme and can be used to compare completely different actuators and control approaches.

  17. Designing a system for patients controlling providers' access to their electronic health records: organizational and technical challenges.

    PubMed

    Leventhal, Jeremy C; Cummins, Jonathan A; Schwartz, Peter H; Martin, Douglas K; Tierney, William M

    2015-01-01

    Electronic health records (EHRs) are proliferating, and financial incentives encourage their use. Applying Fair Information Practice principles to EHRs necessitates balancing patients' rights to control their personal information with providers' data needs to deliver safe, high-quality care. We describe the technical and organizational challenges faced in capturing patients' preferences for patient-controlled EHR access and applying those preferences to an existing EHR. We established an online system for capturing patients' preferences for who could view their EHRs (listing all participating clinic providers individually and categorically-physicians, nurses, other staff) and what data to redact (none, all, or by specific categories of sensitive data or patient age). We then modified existing data-viewing software serving a state-wide health information exchange and a large urban health system and its primary care clinics to allow patients' preferences to guide data displays to providers. Patients could allow or restrict data displays to all clinicians and staff in a demonstration primary care clinic, categories of providers (physicians, nurses, others), or individual providers. They could also restrict access to all EHR data or any or all of five categories of sensitive data (mental and reproductive health, sexually transmitted diseases, HIV/AIDS, and substance abuse) and for specific patient ages. The EHR viewer displayed data via reports, data flowsheets, and coded and free text data displayed by Google-like searches. Unless patients recorded restrictions, by default all requested data were displayed to all providers. Data patients wanted restricted were not displayed, with no indication they were redacted. Technical barriers prevented redacting restricted information in free textnotes. The program allowed providers to hit a "Break the Glass" button to override patients' restrictions, recording the date, time, and next screen viewed. Establishing patient-control

  18. Robust Control of Chaotic Vibrations for Impacting Heat Exchanger Tubes in Crossflow

    NASA Astrophysics Data System (ADS)

    DE BEDOUT, J. M.; FRANCHEK, M. A.; BAJAJ, A. K.

    1999-10-01

    A robust feedback controller design to suppress flutter-type chaotic vibrations in baffled heat exchanger tubes is presented. The vibrations are the result of the fluid dynamic forces on the tube which behave as a negative damping element. A consequence of these vibrations is that the heat exchanger tubes impact with the baffle plates thereby reducing the service life of the heat exchanger. To eliminate the resulting tube impacts, a feedback control strategy is proposed. The heat exchanger tube and the fluid dynamic forces acting on the tube are modeled with linear delayed differential equations. Due to the presence of the delay, these equations do not have a rational realization. The feedback controller is realized using a frequency domain loop shaping approach which is well suited for systems with transcendental transfer functions. The control effector is a magnetic force transducer that acts on the heat exchanger tube. The design strategy is based upon the premise that stabilizing the linear instability about the undeformed tube position will preclude the formation of the nonlinear chaotic vibrations that arise from impacting. The feedback controller is shown to provide robust stability and performance over a large flow velocity regime

  19. Compliance Assurance Monitoring Technical Guidance Document Appendices by Control Technique

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  20. High switching efficiency in FePt exchange coupled composite media mediated by MgO exchange control layers

    NASA Astrophysics Data System (ADS)

    Dutta, Tanmay; Piramanayagam, S. N.; Saifullah, M. S. M.; Bhatia, C. S.

    2017-07-01

    Satisfying the mutually conflicting requirements of easy switchability and high thermal stability still remains a hindrance to achieving ultra-high areal densities in hard disk drives. Exchange coupled composite media used with proper exchange control layers (ECLs) presents a potential solution to circumvent this hindrance. In this work, we have studied the role of MgO and Ta ECLs of different thicknesses in reducing the switching field of FePt media. MgO ECL was found to be more effective than a Ta ECL. For a 2 nm MgO ECL, the switching field could be reduced by 41% and at the cost of only a limited loss in thermal stability. Furthermore, a very high switching efficiency of 1.9 was obtained using 2 nm MgO ECL. So, with a proper choice of ECL material and thickness, the switching field of FePt media can be substantially reduced while ensuring high thermal stability and a better signal-to-noise ratio, thus potentially paving the way for very high areal density media.

  1. 48 CFR 252.204-7012 - Safeguarding of unclassified controlled technical information.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... technology system(s) that may have unclassified controlled technical information resident on or transiting... National Institute of Standards and Technology (NIST) Special Publication (SP) 800-53 security controls... programs, systems and technology; and (iii) Preserve and protect images of known affected information...

  2. Advanced Instrumentation, Information, and Control Systems Technologies Technical Program Plan

    SciTech Connect

    Bruce Hallbert

    2012-09-01

    Reliable instrumentation, information, and control (II&C) systems technologies are essential to ensuring safe and efficient operation of the U.S. light water reactor (LWR) fleet. These technologies affect every aspect of nuclear power plant (NPP) and balance-of-plant operations. In 1997, the National Research Council conducted a study concerning the challenges involved in modernization of digital instrumentation and control systems in NPPs. Their findings identified the need for new II&C technology integration.

  3. U.S.-MEXICO TECHNOLOGY TRANSFER; BILATERAL TECHNICAL EXCHANGES FOR SUSTAINABLE ECONOMIC GROWTH IN THE BORDER REGION

    SciTech Connect

    Jimenez, Richard, D., Dr.

    2007-10-01

    The U.S. Department of Energy (DOE) maintains a strong commitment to transfer the results of its science and technology programs to the private sector. The intent is to apply innovative and sometimes advanced technologies to address needs while simultaneously stimulating new commercial business opportunities. Such focused “technology transfer” was evident in the late 1990s as the results of DOE investments in environmental management technology development led to new tools for characterizing and remediating contaminated sites as well as handling and minimizing the generation of hazardous wastes. The Department’s Office of Environmental Management was attempting to reduce the cost, accelerate the schedule, and improve the efficacy of clean-up efforts in the nuclear weapons complex. It recognized that resulting technologies had broader world market applications and that their commercialization would further reduce costs and facilitate deployment of improved technology at DOE sites. DOE’s Albuquerque Operations Office (now part of the National Nuclear Security Administration) began in 1995 to build the foundation for a technology exchange program with Mexico. Initial sponsorship for this work was provided by the Department’s Office of Environmental Management. As part of this effort, Applied Sciences Laboratory, Inc. (ASL) was contracted by the DOE Albuquerque office to identify Mexico’s priority environmental management needs, identify and evaluate DOE-sponsored technologies as potential solutions for those needs, and coordinate these opportunities with decision makers from Mexico’s federal government. That work led to an improved understanding of many key environmental challenges that Mexico faces and the many opportunities to apply DOE’s technologies to help resolve them. The above results constituted, in large part, the foundation for an initial DOE-funded program to apply the Department’s technology base to help address some of Mexico

  4. Preparation of Cd/Pb Chalcogenide Heterostructured Janus Particles via Controllable Cation Exchange

    SciTech Connect

    Zhang, Jianbing; Chernomordik, Boris D.; Crisp, Ryan W.; Kroupa, Daniel M.; Luther, Joseph M.; Miller, Elisa M.; Gao, Jianbo; Beard, Matthew C.

    2015-07-28

    We developed a strategy for producing quasi-spherical nanocrystals of anisotropic heterostructures of Cd/Pb chalcogenides. The nanostructures are fabricated via a controlled cation exchange reaction where the Cd2+ cation is exchanged for the Pb2+ cation. The cation exchange reaction is thermally activated and can be controlled by adjusting the reaction temperature or time. We characterized the particles using TEM, XPS, PL, and absorption spectroscopy. With complete exchange, high quality Pb-chalcogenide quantum dots are produced. In addition to Cd2+, we also find suitable conditions for the exchange of Zn2+ cations for Pb2+ cations. The cation exchange is anisotropic starting at one edge of the nanocrystals and proceeds along the <111> direction producing a sharp interface at a (111) crystallographic plane. Instead of spherical core/shell structures, we produced and studied quasi-spherical CdS/PbS and CdSe/PbSe Janus-type heterostructures. Nontrivial PL behavior was observed from the CdS(e)/PbS(e) heterostructures as the Pb:Cd ratio is increased.

  5. Electrochemically Controlled Ion-exchange Property of Carbon Nanotubes/Polypyrrole Nanocomposite in Various Electrolyte Solutions

    SciTech Connect

    Choi, Daiwon; Zhu, Chengzhou; Fu, Shaofang; Du, Dan; Engelhard, Mark H.; Lin, Yuehe

    2016-09-15

    The electrochemically controlled ion-exchange properties of multi-wall carbon nanotube (MWNT)/electronically conductive polypyrrole (PPy) polymer composite in the various electrolyte solutions have been investigated. The ion-exchange behavior, rate and capacity of the electrochemically deposited polypyrrole with and without carbon nanotube (CNT) were compared and characterized using cyclic voltammetry (CV), chronoamperometry (CA), electrochemical quartz crystal microbalance (EQCM), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). It has been found that the presence of carbon nanotube backbone resulted in improvement in ion-exchange rate, stability of polypyrrole, and higher anion loading capacity per PPy due to higher surface area, electronic conductivity, porous structure of thin film, and thinner film thickness providing shorter diffusion path. Chronoamperometric studies show that electrically switched anion exchange could be completed more than 10 times faster than pure PPy thin film. The anion selectivity of CNT/PPy film is demonstrated using X-ray photoelectron spectroscopy (XPS).

  6. Film model approximation for particle-diffusion-controlled binary ion exchange

    SciTech Connect

    Carta, G.; Cincotti, A.; Cao, G.

    1999-01-01

    A new rate expression for particle-diffusion-controlled ion exchange, based on an equivalent pseudosteady-state film resistance model, is developed. The rate expression approximates the electric field effects on intraparticle diffusion in spherical ion-exchangers. With regard to the prediction of batch exchange and column breakthrough curves for both irreversible and reversible processes, the model captures the essential traits of the coupled diffusion phenomenon described by the Nernst-Planck equation with results of accuracy comparable to that obtained when using the linear driving force approximation for systems with constant diffusivity. Numerical results for the exchange of two counterions of equal valence are presented as application examples for different mobility ratios and selectivity coefficients.

  7. A brushless dc spin motor for momentum exchange altitude control

    NASA Technical Reports Server (NTRS)

    Stern, D.; Rosenlieb, J. W.

    1972-01-01

    Brushless dc spin motor is designed to use Hall effect probes as means of revolving rotor position and controlling motor winding currents. This results in 3 to 1 reduction in watt-hours required for wheel acceleration, a 2 to 1 reduction in power to run wheel, and a 10 to 1 reduction in the electronics size and weight.

  8. Technical issues in dynamics and control of large space structures

    NASA Technical Reports Server (NTRS)

    Card, M. F.; Anderson, W. W.

    1983-01-01

    Examples of large space systems currently being considered by NASA include a large communications antenna system (the Land Mobile Satellite System), a precision antenna system (the Large Deployable Reflector System), and a preliminary concept for NASA's space station. Each system has low natural vibration frequencies, stringent pointing requirements, and, for the antennas, demanding surface accuracy requirements. A review is provided of the progress being made in structural ground tests with respect to surface accuracy, deployment, and erection of large structures. Attention is given to the dynamic loads on large space structures, on-orbit testing, space vibration control devices, and the characteristics of distributed control.

  9. PIL: A Control Procedure for Technical Services Management *

    PubMed Central

    Ausherman, Marian R.; Wittekind, William D.; Divett, Robert T.

    1967-01-01

    An acquisitions control procedure at the University of New Mexico Library of the Medical Sciences is described. Using an IBM 360/40, a program has been written to keep the acquisitions section and the administration apprised of the status of materials ordered or donated to the library. Future modifications of the program are also described. Images PMID:6066009

  10. Technical support for guidance, navigation and control space shuttle program

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A review of the guidance, navigation and control projects in support of the space shuttle program was conducted. The subjects considered include the following: (1) functional and performance requirements, (2) mission requirements, (3) operating systems software definition, (4) orbit navigation using various sensors, (5) fault detection, isolation and recovery, and (6) passive rendezvous sensors requirements definition.

  11. Final Technical Report: Distributed Controls for High Penetrations of Renewables

    SciTech Connect

    Byrne, Raymond H.; Neely, Jason C.; Rashkin, Lee J.; Trudnowski, Daniel J.; Wilson, David G.

    2015-12-01

    The goal of this effort was to apply four potential control analysis/design approaches to the design of distributed grid control systems to address the impact of latency and communications uncertainty with high penetrations of photovoltaic (PV) generation. The four techniques considered were: optimal fixed structure control; Nyquist stability criterion; vector Lyapunov analysis; and Hamiltonian design methods. A reduced order model of the Western Electricity Coordinating Council (WECC) developed for the Matlab Power Systems Toolbox (PST) was employed for the study, as well as representative smaller systems (e.g., a two-area, three-area, and four-area power system). Excellent results were obtained with the optimal fixed structure approach, and the methodology we developed was published in a journal article. This approach is promising because it offers a method for designing optimal control systems with the feedback signals available from Phasor Measurement Unit (PMU) data as opposed to full state feedback or the design of an observer. The Nyquist approach inherently handles time delay and incorporates performance guarantees (e.g., gain and phase margin). We developed a technique that works for moderate sized systems, but the approach does not scale well to extremely large system because of computational complexity. The vector Lyapunov approach was applied to a two area model to demonstrate the utility for modeling communications uncertainty. Application to large power systems requires a method to automatically expand/contract the state space and partition the system so that communications uncertainty can be considered. The Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) design methodology was selected to investigate grid systems for energy storage requirements to support high penetration of variable or stochastic generation (such as wind and PV) and loads. This method was applied to several small system models.

  12. The Importance of Postural Control in Relation to Technical Abilities in Small-Sided Soccer Games.

    PubMed

    Edis, Çağlar; Vural, Faik; Vurgun, Hikmet

    2016-12-01

    Making assessments regarding postural control and balance is very important for injury prevention in soccer. However, there has been no study that has associated postural control variables with branch-specific technical properties in a game. The aim of the present study was to determine the relationships between variables designating postural control levels and technical performance variables in different (1:1, 2:2 and 3:3) small-sided games (SSGs). Sixteen trained male amateur soccer players volunteered to take part in the study (age 17.2 ± 1.02 years, body height 176.25 ± 0.07 m, body mass 67.67 ± 13.27 kg). Following familiarization sessions, postural control was evaluated using one-leg and both-leg quiet-stance positions by measuring postural sway with a Tekscan HR Mat™ in anterior-posterior and medial-lateral directions. Later, 1:1, 2:2 and 3:3 SSGs were performed at two-day intervals and the technical variables specified for each game were analyzed. A Spearman's rank-order correlation analysis demonstrated the relationship between postural control and soccer-specific technical variables in 1:1 (r-values ranging from 0.582 to 0.776), 2:2 (rvalues ranging from 0.511 to 0.740) and 3:3 (r-values ranging from 0.502 to 0.834) SSGs. In addition, a Wilcoxon signed rank test revealed differences between SSGs in terms of several variables. The results of the study showed that higher postural control levels are among the important variables that affect success in the performance of technical skills under rival pressure and suddenly changing conditions. Therefore, it is recommended that in addition to its use for injury prevention purposes, balance training should be conducted to improve branch-specific technical skills and to increase the levels of their successful performance in a game.

  13. Description of emission control using fluidized-bed, heat-exchange technology

    SciTech Connect

    Vogel, G.J.; Grogan, P.J.

    1980-06-01

    Environmental effects of fluidized-bed, waste-heat recovery technology are identified. The report focuses on a particular configuration of fluidized-bed, heat-exchange technology for a hypothetical industrial application. The application is a lead smelter where a fluidized-bed, waste-heat boiler (FBWHB) is used to control environmental pollutants and to produce steam for process use. Basic thermodynamic and kinetic information for the major sulfur dioxide (SO/sub 2/) and NO/sub x/ removal processes is presented and their application to fluidized-bed, waste heat recovery technology is discussed. Particulate control in fluidized-bed heat exchangers is also discussed.

  14. Improved Controls for Fusion RF Systems. Final technical report

    SciTech Connect

    Casey, Jeffrey A.

    2011-11-08

    We have addressed the specific requirements for the integrated systems controlling an array of klystrons used for Lower Hybrid Current Drive (LHCD). The immediate goal for our design was to modernize the transmitter protection system (TPS) for LHCD on the Alcator C-Mod tokamak at the MIT Plasma Science and Fusion Center (MIT-PSFC). Working with the Alcator C-Mod team, we have upgraded the design of these controls to retrofit for improvements in performance and safety, as well as to facilitate the upcoming expansion from 12 to 16 klystrons. The longer range goals to generalize the designs in such a way that they will be of benefit to other programs within the international fusion effort was met by designing a system which was flexible enough to address all the MIT system requirements, and modular enough to adapt to a large variety of other requirements with minimal reconfiguration.

  15. [DELTA T dryer/moisture control system]. Final technical report

    SciTech Connect

    Not Available

    1995-01-01

    Drying Technology, Inc. was awarded a grant for the purpose of extending DELTA T dryer/moisture control technology into additional industries. Ultimate purpose of the grant was to save energy and improve efficiency in the process industries. Results indicate that these objectives have been met and will continue as this new technology is duplicated in the present industries and also is extended into other industries as well.

  16. Technical Report: Impacts of Land Management and Climate on Agroecosystem Greenhouse Gas Exchange in the Upper Midwest United States

    SciTech Connect

    Timothy J. Griffis; John M. Baker

    2007-07-01

    Our research is designed to improve the scientific understanding of how carbon is cycled between the land and atmosphere within a heavily managed landscape that is characteristic of the Upper Midwest. The Objectives are: 1) Quantify the seasonal and interannual variation of net ecosystem CO2 exchange of agricultural ecosystems in the Upper Midwest grown under different management strategies; 2) Partition net ecosystem CO2 exchange into photosynthesis and ecosystem respiration by combining micrometeorological and stable isotope techniques; 3) Examine the seasonal variation in canopy-scale photosynthetic discrimination and the isotope ratios of ecosystem respiration and photosynthesis.

  17. Temperature-dependent variation in gas exchange patterns and spiracular control in Rhodnius prolixus.

    PubMed

    Heinrich, Erica; Bradley, Timothy

    2014-08-01

    Insects display an array of respiratory behaviors, including the use of discontinuous gas exchange. This pattern is characterized by periods of spiracular closure, micro-openings (flutter), and complete openings during which the majority of gas exchange takes place. A current model of insect spiracular control suggests that spiracles are controlled by two interacting feedback loops, which produce the discontinuous pattern. The flutter period is thought to be initiated by a critically low partial pressure of oxygen, while the open period is initiated by a critically high CO2 threshold. The goal of our study was to test this control model under conditions of feeding-induced or temperature-induced changes in metabolic rate. We manipulated the metabolic rate of the insect Rhodnius prolixus using two discrete mechanisms: (1) feeding the insects a bloodmeal or (2) exposing them to a range of temperatures (18-38°C). Examining the variation in the gas exchange patterns produced by insects in each of these treatments allowed us to determine whether spiracular control is sensitive to metabolic rate and/or temperature. We found that increases in temperature caused significant decreases in open phase burst volumes and premature abandonment of discontinuous gas exchange cycles. These effects were not observed in fed individuals maintained at a single temperature despite their higher metabolic rates. Our results indicate that some part of the spiracular control mechanism is temperature sensitive, suggesting a possible role for pH in CO2 sensing.

  18. Voltage controlled exchange bias in an all-thin-film Cr2O3 based heterostructure

    NASA Astrophysics Data System (ADS)

    Echtenkamp, Will; Binek, Christian

    2014-03-01

    Spintronics utilizes the electron's spin degree of freedom for an advanced generation of electronic devices with novel functionalities. Controlling magnetism by electrical means has been identified as a key challenge in the field of spintronics, and electric control of exchange bias is one of the most promising routes to address this challenge. Previously, robust isothermal electric control of exchange bias has been achieved near room temperature utilizing a bulk single crystal of Cr2O3. In this study electric control of exchange bias in an all-thin-film system is demonstrated with significant implications for device realization. In particular, voltage controlled switching of exchange bias in a Cr2O3 based magnetoelectric magnetic tunnel junction enables nonvolatile memory storage with virtually dissipationless writing at, or above, room temperature. Additionally, unique physical properties which arise due to the Cr2O3 thin film geometry are highlighted. This project is supported by NSF through MRSEC DMR 0213808, by the NRC/NRI supplement to MRSEC, and by CNFD and C-SPIN, one of six centers of STARnet, a Semiconductor Research Corporation program.

  19. CONTACT: An Air Force technical report on military satellite control technology

    NASA Astrophysics Data System (ADS)

    Weakley, Christopher K.

    1993-07-01

    This technical report focuses on Military Satellite Control Technologies and their application to the Air Force Satellite Control Network (AFSCN). This report is a compilation of articles that provide an overview of the AFSCN and the Advanced Technology Program, and discusses relevant technical issues and developments applicable to the AFSCN. Among the topics covered are articles on Future Technology Projections; Future AFSCN Topologies; Modeling of the AFSCN; Wide Area Communications Technology Evolution; Automating AFSCN Resource Scheduling; Health & Status Monitoring at Remote Tracking Stations; Software Metrics and Tools for Measuring AFSCN Software Performance; Human-Computer Interface Working Group; Trusted Systems Workshop; and the University Technical Interaction Program. In addition, Key Technology Area points of contact are listed in the report.

  20. Capture and isotopic exchange method for water and hydrogen isotopes on zeolite catalysts up to technical scale for pre-study of processing highly tritiated water

    SciTech Connect

    Michling, R.; Braun, A.; Cristescu, I.; Dittrich, H.; Gramlich, N.; Lohr, N.; Glugla, M.; Shu, W.; Willms, S.

    2015-03-15

    Highly tritiated water (HTW) may be generated at ITER by various processes and, due to the excessive radio toxicity, the self-radiolysis and the exceedingly corrosive property of HTW, a potential hazard is associated with its storage and process. Therefore, the capture and exchange method for HTW utilizing Molecular Sieve Beds (MSB) was investigated in view of adsorption capacity, isotopic exchange performance and process parameters. For the MSB, different types of zeolite were selected. All zeolite materials were additionally coated with platinum. The following work comprised the selection of the most efficient zeolite candidate based on detailed parametric studies during the H{sub 2}/D{sub 2}O laboratory scale exchange experiments (about 25 g zeolite per bed) at the Tritium Laboratory Karlsruhe (TLK). For the zeolite, characterization analytical techniques such as Infrared Spectroscopy, Thermogravimetry and online mass spectrometry were implemented. Followed by further investigation of the selected zeolite catalyst under full technical operation, a MSB (about 22 kg zeolite) was processed with hydrogen flow rates up to 60 mol*h{sup -1} and deuterated water loads up to 1.6 kg in view of later ITER processing of arising HTW. (authors)

  1. Na+/Ca2+ exchangers: three mammalian gene families control Ca2+ transport.

    PubMed

    Lytton, Jonathan

    2007-09-15

    Mammalian Na+/Ca2+ exchangers are members of three branches of a much larger family of transport proteins [the CaCA (Ca2+/cation antiporter) superfamily] whose main role is to provide control of Ca2+ flux across the plasma membranes or intracellular compartments. Since cytosolic levels of Ca2+ are much lower than those found extracellularly or in sequestered stores, the major function of Na+/Ca2+ exchangers is to extrude Ca2+ from the cytoplasm. The exchangers are, however, fully reversible and thus, under special conditions of subcellular localization and compartmentalized ion gradients, Na+/Ca2+ exchangers may allow Ca2+ entry and may play more specialized roles in Ca2+ movement between compartments. The NCX (Na+/Ca2+ exchanger) [SLC (solute carrier) 8] branch of Na+/Ca2+ exchangers comprises three members: NCX1 has been most extensively studied, and is broadly expressed with particular abundance in heart, brain and kidney, NCX2 is expressed in brain, and NCX3 is expressed in brain and skeletal muscle. The NCX proteins subserve a variety of roles, depending upon the site of expression. These include cardiac excitation-contraction coupling, neuronal signalling and Ca2+ reabsorption in the kidney. The NCKX (Na2+/Ca2+-K+ exchanger) (SLC24) branch of Na+/Ca2+ exchangers transport K+ and Ca2+ in exchange for Na+, and comprises five members: NCKX1 is expressed in retinal rod photoreceptors, NCKX2 is expressed in cone photoreceptors and in neurons throughout the brain, NCKX3 and NCKX4 are abundant in brain, but have a broader tissue distribution, and NCKX5 is expressed in skin, retinal epithelium and brain. The NCKX proteins probably play a particularly prominent role in regulating Ca2+ flux in environments which experience wide and frequent fluctuations in Na+ concentration. Until recently, the range of functions that NCKX proteins play was generally underappreciated. This situation is now changing rapidly as evidence emerges for roles including photoreceptor

  2. The Ownership and Control of the U.S. Securities and Exchange Commission's EDGAR System.

    ERIC Educational Resources Information Center

    Love, James Packard

    1993-01-01

    Describes the EDGAR (Electronic Data Gathering, Analysis and Retrieval) system developed for the U.S. Securities and Exchange Commission (SEC) for SEC disclosure filings. Ownership and control of the database, hardware, and software is considered; the Information Industry Association position is described; and the need for greater public access to…

  3. 145. VIEW OF LIQUID NITROGEN/HELIUM HEAT EXCHANGER IN FUEL CONTROL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    145. VIEW OF LIQUID NITROGEN/HELIUM HEAT EXCHANGER IN FUEL CONTROL ROOM (215), LSB (BLDG. 751), FROM FUEL APRON WITH BAY DOOR OPEN - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. Demonstration of leapfrogging for implementing nonlinear model predictive control on a heat exchanger.

    PubMed

    Sridhar, Upasana Manimegalai; Govindarajan, Anand; Rhinehart, R Russell

    2016-01-01

    This work reveals the applicability of a relatively new optimization technique, Leapfrogging, for both nonlinear regression modeling and a methodology for nonlinear model-predictive control. Both are relatively simple, yet effective. The application on a nonlinear, pilot-scale, shell-and-tube heat exchanger reveals practicability of the techniques.

  5. Control of catalytic hydrotreating selectivity with ammonia. Final technical report

    SciTech Connect

    Satterfield, C.N.; Lee, C.; Gultekin, S.

    1993-11-01

    The purpose of this study was to explore the possibility of control of product selectivity in the hydroprocessing of coal liquids and related substances by adding small amounts of ammonia. Quinoline was used in this study and in many others as representative of heterocyclic N compounds found in coal liquids. Coal liquids also contain hydroxy pyridines, but by studies with 8-OH quinoline, a representative compound (Part I), we demonstrated that the OH group was rapidly removed at the beginning of reaction to form quinoline, which reacted in the same manner as quinoline fed as such. In Part II we showed that in a mixture of naphthalene and quinoline, with the addition of ammonia there is an operating region in which complete HDN of quinoline can be achieved, but with greater conversion of naphthalene to tetralin instead of to decalin than was the case in the absence of added ammonia. This is of some significance to coal liquefaction since tetralin is a good hydrogen donor, but decalin is not. In Part III we showed that NH{sub 3} addition to a mixture of quinoline and phenanthrene provides an operating region where complete HDN of quinoline can be achieved with reduced formation of hydrogenated phenanthrenes and cracking to biphenyl. Part IV, a study of the hydrodeoxygenation (DHO) of dibenzofuran in the presence of naphthalene, showed that NH{sub 3} strongly inhibits HDO reactions and its effects on naphthalene here were much the same as in Part II. In Part V it was demonstrated that in the hydrotreating of propylbenzene, the addition of ammonia increased the selectivity towards ring hydrogenation (generally desired for reformulated motor fuels) and away from dealkylation (generally undesired), but the overall reaction rate at a fixed temperature drops substantially.

  6. Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). PRE-SPC I. Instructor Book.

    ERIC Educational Resources Information Center

    Averitt, Sallie D.

    This instructor guide, which was developed for use in a manufacturing firm's advanced technical preparation program, contains the materials required to present a learning module that is designed to prepare trainees for the program's statistical process control module by improving their basic math skills and instructing them in basic calculator…

  7. Project T.E.A.M. (Technical Education Advancement Modules). Introduction to Statistical Process Control.

    ERIC Educational Resources Information Center

    Billings, Paul H.

    This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 6-hour introductory module on statistical process control (SPC), designed to develop competencies in the following skill areas: (1) identification of the three classes of SPC use; (2) understanding a process and how it works; (3)…

  8. Project T.E.A.M. (Technical Education Advancement Modules). Advanced Statistical Process Control.

    ERIC Educational Resources Information Center

    Dunlap, Dale

    This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 20-hour advanced statistical process control (SPC) and quality improvement course designed to develop the following competencies: (1) understanding quality systems; (2) knowing the process; (3) solving quality problems; and (4)…

  9. Control of the Physical and Technical Properties of Water in Technological Processes

    NASA Astrophysics Data System (ADS)

    Klopotov, V. D.; Gorlenko, N. P.; Sarkisov, Yu S.; Kulchenko, A. K.; Klopotov, A. A.

    2016-08-01

    The physical and technical properties of water activated by the electrochemical treatment in a two-chamber electrolizer are investigated. The regularities of changes inthe values of acidity, redox potential, ionic composition, concentration of oxygen, structural organization of catholyte and anolyte are revealed. The possibility of controlling the properties of the liquid for more efficient extraction of polymetallic minerals by flotation is described.

  10. Handbook on heat exchangers

    NASA Astrophysics Data System (ADS)

    Bazhan, Pavel I.; Kanevets, Georgii E.; Seliverstov, Vladimir M.

    Essential data on heat exchange equipment used in ship, locomotive, automotive, and aircraft powerplants are presented in a systematic manner. The data cover the principal types and technical and performance characteristics of heat exchangers, fundamentals of the theory of heat exchange, calculation of heat transfer coefficients for different types of heat exchange apparatus, optimization of heat exchangers, computer-aided design of heat exchange equipment, testing techniques, and test result processing.

  11. Tracking pulmonary gas exchange by breathing control during exercise: role of muscle blood flow

    PubMed Central

    Haouzi, Philippe

    2014-01-01

    Populations of group III and IV muscle afferent fibres located in the adventitia of the small vessels appear to respond to the level of venular distension and to recruitment of the vascular bed within the skeletal muscles. The CNS could thus be informed on the level of muscle hyperaemia when the metabolic rate varies. As a result, the magnitude and kinetics of the change in peripheral gas exchange – which translates into pulmonary gas exchange – can be sensed. We present the view that the respiratory control system uses these sources of information of vascular origin, among the numerous inputs produced by exercise, as a marker of the metabolic strain imposed on the circulatory and the ventilatory systems, resulting in an apparent matching between pulmonary gas exchange and alveolar ventilation. PMID:23981720

  12. Controlled state-to-state atom-exchange reaction in an ultracold atom-dimer mixture

    NASA Astrophysics Data System (ADS)

    Rui, Jun; Yang, Huan; Liu, Lan; Zhang, De-Chao; Liu, Ya-Xiong; Nan, Jue; Chen, Yu-Ao; Zhao, Bo; Pan, Jian-Wei

    2017-07-01

    Ultracold molecules offer remarkable opportunities for the study of chemical reactions close to zero temperature. Although significant progress has been achieved in exploring ultracold bimolecular reactions, the investigations are usually limited to measurements of the overall loss rates of the reactants. Detection of the reaction products will improve our understanding of the reaction mechanism and provide a unique opportunity to study the state-to-state reaction dynamics. Here we report on the direct observation of an exoergic atom-exchange reaction in an ultracold atom-dimer mixture. Both the atom and molecule products are observed and the state-to-state reaction rate coefficient is measured. By changing the magnetic field, the reaction can be switched on or off, and the rate coefficient can be controlled. The observed atom-exchange reaction is an effective spin-exchange interaction between the dimer and the atom and may be exploited to study the Kondo effect with ultracold atoms.

  13. Controlled exchange interaction for quantum logic operations with spin qubits in coupled quantum dots

    SciTech Connect

    Moskal, S.; Bednarek, S.; Adamowski, J.

    2007-09-15

    A two-electron system confined in two coupled semiconductor quantum dots is investigated as a candidate for performing quantum logic operations with spin qubits. We study different processes of swapping the electron spins by a controlled switching on and off of the exchange interaction. The resulting spin swap corresponds to an elementary operation in quantum-information processing. We perform direct simulations of the time evolution of the two-electron system. Our results show that, in order to obtain the full interchange of spins, the exchange interaction should change smoothly in time. The presence of jumps and spikes in the time characteristics of the confinement potential leads to a considerable increase of the spin-swap time. We propose several mechanisms to modify the exchange interaction by changing the confinement potential profile and discuss their advantages and disadvantages.

  14. Reversible Control of Nanoparticle Functionalization and Physicochemical Properties by Dynamic Covalent Exchange.

    PubMed

    Della Sala, Flavio; Kay, Euan R

    2015-03-27

    Existing methods for the covalent functionalization of nanoparticles rely on kinetically controlled reactions, and largely lack the sophistication of the preeminent oligonucleotide-based noncovalent strategies. Here we report the application of dynamic covalent chemistry for the reversible modification of nanoparticle (NP) surface functionality, combining the benefits of non-biomolecular covalent chemistry with the favorable features of equilibrium processes. A homogeneous monolayer of nanoparticle-bound hydrazones can undergo quantitative dynamic covalent exchange. The pseudomolecular nature of the NP system allows for the in situ characterization of surface-bound species, and real-time tracking of the exchange reactions. Furthermore, dynamic covalent exchange offers a simple approach for reversibly switching-and subtly tuning-NP properties such as solvophilicity.

  15. Instrumentation and Controls Division, Technical Support Department Management Plan, FY 1993--FY 1996

    SciTech Connect

    Adkisson, B.P.; Kunselman, C.W.; Effler, R.P.; Miller, D.R.; Millet, A.J.; Stansberry, C.T.

    1993-08-01

    This report describes the organization, key functions, and major activities of the Technical Support Department The Department is the programmatic support element of the Instrumentation and Controls Division. The Department`s primary focus is the support of existing equipment and systems at Oak Ridge National Laboratory that are generally characterized as instrumentation and controls. The support takes the form of repair, calibration, fabrication, field engineering, preventive maintenance, software support, and record keeping.

  16. Voltage Controlled Exchange Bias in a Cr2O3 based heterostructure

    NASA Astrophysics Data System (ADS)

    Echtenkamp, Will; Street, Mike; Binek, Christian

    2015-03-01

    Controlling magnetism by electrical means is a key challenge in the field of spintronics, and electric control of exchange bias is one of the most promising routes to address this challenge. Isothermal electric control of exchange bias has been achieved near room temperature using bulk, single crystal, magnetoelectric Cr2O3, which has a voltage controlled net magnetization at the (0001) surface. Voltage control of magnetism in a Cr2O3 thin film system has presented significant challenges. In this study we explore the electric control of exchange bias in an all-thin-film system of decreasing chromia film thickness with significant implications for scalability of ultra-low power memory and logical devices. Cross-sectional HRTEM indicates that grain boundaries in the metallic bottom electrode propagate into the Cr2O3 thin film with detrimental effects on leakage currents. We address this issue via a three-step growth method for the deposition of epitaxial Pd on sapphire. The resulting microstructure of the films is analyzed by reflection high-energy electron diffraction, tunneling electron microscopy and x-ray diffraction. This project was supported by SRC through CNFD, an SRC-NRI Center, by C-SPIN, part of STARnet, and by the NSF through MRSEC DMR-0820521.

  17. Hydraulic controls of in-stream gravel bar hyporheic exchange and reactions

    NASA Astrophysics Data System (ADS)

    Trauth, Nico; Schmidt, Christian; Vieweg, Michael; Oswald, Sascha E.; Fleckenstein, Jan H.

    2015-04-01

    Hyporheic exchange transports solutes into the subsurface where they can undergo biogeochemical transformations, affecting fluvial water quality and ecology. A three-dimensional numerical model of a natural in-stream gravel bar (20 m × 6 m) is presented. Multiple steady state streamflow is simulated with a computational fluid dynamics code that is sequentially coupled to a reactive transport groundwater model via the hydraulic head distribution at the streambed. Ambient groundwater flow is considered by scenarios of neutral, gaining, and losing conditions. The transformation of oxygen, nitrate, and dissolved organic carbon by aerobic respiration and denitrification in the hyporheic zone are modeled, as is the denitrification of groundwater-borne nitrate when mixed with stream-sourced carbon. In contrast to fully submerged structures, hyporheic exchange flux decreases with increasing stream discharge, due to decreasing hydraulic head gradients across the partially submerged structure. Hyporheic residence time distributions are skewed in the log-space with medians of up to 8 h and shift to symmetric distributions with increasing level of submergence. Solute turnover is mainly controlled by residence times and the extent of the hyporheic exchange flow, which defines the potential reaction area. Although streamflow is the primary driver of hyporheic exchange, its impact on hyporheic exchange flux, residence times, and solute turnover is small, as these quantities exponentially decrease under losing and gaining conditions. Hence, highest reaction potential exists under neutral conditions, when the capacity for denitrification in the partially submerged structure can be orders of magnitude higher than in fully submerged structures.

  18. Synthesis of Ultrathin and Thickness-Controlled Cu2-xSe Nanosheets via Cation Exchange.

    PubMed

    Wang, Yuanxing; Zhukovskyi, Maksym; Tongying, Pornthip; Tian, Yang; Kuno, Masaru

    2014-11-06

    We demonstrate the use of cation exchange to synthesize ultrathin and thickness-controlled Cu2-xSe nanosheets (NSs) beginning with CdSe NSs. In this manner, extremely thin (i.e., 1.6 nm thickness) Cu2-xSe NSs, beyond which can be made directly, have been obtained. Furthermore, they represent the thinnest NSs produced via cation exchange. Notably, the exchange reaction preserves the starting morphology of the CdSe sheets and also retains their cubic crystal structure. The resulting nonstoichiometric and cubic Cu2-xSe NSs are stable and do not exhibit any signs of Cu or Se oxidation after exposure to air for 2 weeks. Resulting NSs also show the existence of a localized surface plasmon resonance in the infrared due to the presence of copper vacancies. Efforts to isolate intermediates during the cation exchange reaction show that it occurs via a mechanism where entire sheets are rapidly converted into the final product once the exchange reaction commences, precluding the isolation of alloyed species.

  19. The Importance of Winter for Controlling the Growing Season Net Ecosystem Exchange (NEE) of Boreal Forests

    NASA Astrophysics Data System (ADS)

    Oquist, M. G.; Peichl, M.; Ottosson Lofvenius, M.; Nilsson, M. B.

    2014-12-01

    It is becoming increasingly apparent that the winter season of high latitudes can be important for controlling a range of ecological and biogeochemical properties of northern ecosystems. Here we evaluate the importance of winter conditions on the carbon exchange between boreal forest systems and the atmosphere during the following growing season in order to elucidate any influence of inter-seasonal "memory" effects on carbon exchange properties of boreal forest ecosystems. The study is based on 5 years of continuous eddy covariance measurements at two ca 50 year old Norway spruce stands situated in mid- and northern Sweden, respectively (a total of 10 site years). The growing season net ecosystem exchange (NEE) ranged from -530 to -60 g C m-2 (negative values indicates carbon sinks). Environmental conditions during the growing season (e.g. temperature, radiation, length) only weakly explained the year-to-year variability in NEE. In contrast, up to 75% of the variation could be explained by the severity of the preceding winter (defined as the lowest observed average weekly air temperature) using an exponential response function. After warm winters the carbon sink properties were high as compared to those observed after cold winters. The winter conditions markedly affected the systems potential for carbon uptake in early summer. This presentation will address the potential mechanisms underpinning the observed correlations linking growing season carbon exchange to the conditions of the preceding winter. The influence of winter on the partitioned carbon fluxes of ecosystem respiration and gross primary productivity, respectively, will also be addressed. The results strongly indicate that controls on boreal forest carbon exchange can transcend across seasons. Understanding these mechanisms are integral for understanding the environmental drivers of atmospheric carbon exchange, allowing for accurate predictions of boreal forest NEE under both present and future climates.

  20. Characteristics of mineral nutrition of plants in the bio-technical life support system with human wastes included in mass exchange

    NASA Astrophysics Data System (ADS)

    Tikhomirova, Natalia; Ushakova, Sofya; Kalacheva, Galina; Tikhomirov, Alexander

    2016-09-01

    The study addresses the effectiveness of using ion exchange substrates (IES) to optimize mineral nutrition of plants grown in the nutrient solutions containing oxidized human wastes for application in bio-technical life support systems. The study shows that the addition of IES to the root-inhabited substrate is favorable for the growth of wheat vegetative organs but causes a decrease in the grain yield. By contrast, the addition of IES to the nutrient solution does not influence the growth of vegetative organs but favors normal development of wheat reproductive organs. Thus, to choose the proper method of adjusting the solution with IES, one should take into account specific parameters of plant growth and development and the possibility of multiple recycling of IES based on the liquid products of mineralization of human wastes.

  1. Energetics and Control of Ultracold Isotope-Exchange Reactions between Heteronuclear Dimers in External Fields.

    PubMed

    Tomza, Michał

    2015-08-07

    We show that isotope-exchange reactions between ground-state alkali-metal, alkaline-earth-metal, and lanthanide heteronuclear dimers consisting of two isotopes of the same atom are exothermic with an energy change in the range of 1-8000 MHz, thus resulting in cold or ultracold products. For these chemical reactions, there are only one rovibrational and at most several hyperfine possible product states. The number and energetics of open and closed reactive channels can be controlled by the laser and magnetic fields. We suggest a laser-induced isotope- and state-selective Stark shift control to tune the exothermic isotope-exchange reactions to become endothermic, thus providing the ground for testing models of the chemical reactivity. The present proposal opens the way for studying the state-to-state dynamics of ultracold chemical reactions beyond the universal limit with a meaningful control over the quantum states of both reactants and products.

  2. [Technical requirements for buying a heat and humidity exchanger for ventilation during anesthesia. French Society of Anesthesia and Intensive Care].

    PubMed

    Hajjar, J; Loctin, H; Goullet, D

    2000-08-01

    To prevent cross infection and to improve the management of anaesthetic circuits, the French society of anesthesia and intensive care recommended the use of heat and moisture exchange filter (HMEF). Buying a HMEF needs a procedure with different steps and a product request form must delineate precise needed requirements of the device. In the absence of standardized methods to assess filtration performance, required specifications are established from both manufacturer data and scientific published studies. Proposed purchasing method and criteria help the health care workers at the time of final decision for objective comparison between the different devices on the market.

  3. Exchange Bias Optimization by Controlled Oxidation of Cobalt Nanoparticle Films Prepared by Sputter Gas Aggregation.

    PubMed

    Antón, Ricardo López; González, Juan A; Andrés, Juan P; Normile, Peter S; Canales-Vázquez, Jesús; Muñiz, Pablo; Riveiro, José M; De Toro, José A

    2017-03-11

    Porous films of cobalt nanoparticles have been obtained by sputter gas aggregation and controllably oxidized by air annealing at 100 °C for progressively longer times (up to more than 1400 h). The magnetic properties of the samples were monitored during the process, with a focus on the exchange bias field. Air annealing proves to be a convenient way to control the Co/CoO ratio in the samples, allowing the optimization of the exchange bias field to a value above 6 kOe at 5 K. The occurrence of the maximum in the exchange bias field is understood in terms of the density of CoO uncompensated spins and their degree of pinning, with the former reducing and the latter increasing upon the growth of a progressively thicker CoO shell. Vertical shifts exhibited in the magnetization loops are found to correlate qualitatively with the peak in the exchange bias field, while an increase in vertical shift observed for longer oxidation times may be explained by a growing fraction of almost completely oxidized particles. The presence of a hummingbird-like form in magnetization loops can be understood in terms of a combination of hard (biased) and soft (unbiased) components; however, the precise origin of the soft phase is as yet unresolved.

  4. Exchange Bias Optimization by Controlled Oxidation of Cobalt Nanoparticle Films Prepared by Sputter Gas Aggregation

    PubMed Central

    Antón, Ricardo López; González, Juan A.; Andrés, Juan P.; Normile, Peter S.; Canales-Vázquez, Jesús; Muñiz, Pablo; Riveiro, José M.; De Toro, José A.

    2017-01-01

    Porous films of cobalt nanoparticles have been obtained by sputter gas aggregation and controllably oxidized by air annealing at 100 °C for progressively longer times (up to more than 1400 h). The magnetic properties of the samples were monitored during the process, with a focus on the exchange bias field. Air annealing proves to be a convenient way to control the Co/CoO ratio in the samples, allowing the optimization of the exchange bias field to a value above 6 kOe at 5 K. The occurrence of the maximum in the exchange bias field is understood in terms of the density of CoO uncompensated spins and their degree of pinning, with the former reducing and the latter increasing upon the growth of a progressively thicker CoO shell. Vertical shifts exhibited in the magnetization loops are found to correlate qualitatively with the peak in the exchange bias field, while an increase in vertical shift observed for longer oxidation times may be explained by a growing fraction of almost completely oxidized particles. The presence of a hummingbird-like form in magnetization loops can be understood in terms of a combination of hard (biased) and soft (unbiased) components; however, the precise origin of the soft phase is as yet unresolved. PMID:28336895

  5. The Importance of Postural Control in Relation to Technical Abilities in Small-Sided Soccer Games

    PubMed Central

    Edis, Çağlar; Vurgun, Hikmet

    2016-01-01

    Abstract Making assessments regarding postural control and balance is very important for injury prevention in soccer. However, there has been no study that has associated postural control variables with branch-specific technical properties in a game. The aim of the present study was to determine the relationships between variables designating postural control levels and technical performance variables in different (1:1, 2:2 and 3:3) small-sided games (SSGs). Sixteen trained male amateur soccer players volunteered to take part in the study (age 17.2 ± 1.02 years, body height 176.25 ± 0.07 m, body mass 67.67 ± 13.27 kg). Following familiarization sessions, postural control was evaluated using one-leg and both-leg quiet-stance positions by measuring postural sway with a Tekscan HR Mat™ in anterior–posterior and medial–lateral directions. Later, 1:1, 2:2 and 3:3 SSGs were performed at two-day intervals and the technical variables specified for each game were analyzed. A Spearman’s rank-order correlation analysis demonstrated the relationship between postural control and soccer-specific technical variables in 1:1 (r-values ranging from 0.582 to 0.776), 2:2 (rvalues ranging from 0.511 to 0.740) and 3:3 (r-values ranging from 0.502 to 0.834) SSGs. In addition, a Wilcoxon signed rank test revealed differences between SSGs in terms of several variables. The results of the study showed that higher postural control levels are among the important variables that affect success in the performance of technical skills under rival pressure and suddenly changing conditions. Therefore, it is recommended that in addition to its use for injury prevention purposes, balance training should be conducted to improve branch-specific technical skills and to increase the levels of their successful performance in a game. PMID:28149410

  6. Anion-exchange resin-based desulfurization process. Quarterly technical progress report, January 1, 1993--March 31, 1993

    SciTech Connect

    Sheth, A.C.; Dharmapurikar, R.

    1993-06-01

    Under DOE Grant No. FG22-90PC90309, the University of Tennessee Space Institute (UTSI) is contracted to further develop its anion-exchange, resin-based desulfurization concept to desulfurize alkali metal sulfates. From environmental as well as economic viewpoints, it is necessary to remove soluble sulfates from the wastes created by flue gas desulfurization systems. In order to do this economically, a low-cost desulfurization process for spent sorbents is necessary. UTSI`s anion-exchange resin-based desulfurization concept is believed to satisfy these requirements. UTSI has completed the batch mode experiments to locate the position of the CO{sub 3}{sup 2} and SO{sub 4}{sup 2} ions in the affinity chart. Also, the reviews of the ASPEN Code`s capabilities and EPRI-TAG document`s methodology are in progress for developing the Best Process Schematic and related economics. The fixed-bed experiments are also in progress to evaluate the cycle efficiency of the candidate resins. So far we have completed ten consecutive cycles of exhaustion/carbonation and regeneration for IRA-35 resin. Because of the past problems (now resolved) with the fixed-bed system, the addition of batch mode screening experiments, Christmas holidays and spring break, and the moving of UTSI`s Chemistry Laboratory to a new location, the program is about 6--8 weeks behind schedule, but well within the budget.

  7. Anion-exchange resin-based desulfurization process. Annual technical progress report, October 1, 1992--September 30, 1993

    SciTech Connect

    Sheth, A.C.; Dharmapurikar, R.; Strevel, S.D.

    1993-11-01

    Under the DOE Grant No. DE-FG22-90PC90309, the University of Tennessee Space Institute (UTSI) has been directed to further develop an anion-exchange, resin-based desulfurization concept that has been developed and tested on a limited scope for feasibility. From environmental as well as the economic viewpoints, it is necessary that the soluble sulfates of alkali metal sorbents be desulfurized (regenerated) and recycled to make regenerative flue gas desulfurization and MHD spent seed regeneration options more attractive. In order to achieve this, a low-temperature, low-cost desulfurization process to reactivate spent alkali metal sorbents is necessary. UTSI`s anion-exchange, resin-based concept uses the available technology and is believed to satisfy this requirement. In this DOE-sponsored project, UTSI, will perform the following investigations: Screening of commercially available resins; process variables study and improving resin performance; optimization of resin-regeneration step; evaluation of performance enhancers; development of Best-Process Schematic and related economics, and planning for proof-of-concept (POC) scale testing. The above activities have been grouped into five major tasks and the entire project is expected to take thirty-six months to complete.

  8. A computational model of insect discontinuous gas exchange: A two-sensor, control systems approach.

    PubMed

    Grieshaber, Beverley J; Terblanche, John S

    2015-06-07

    The insect gas exchange system is characterised by branching air-filled tubes (tracheae/tracheoles) and valve-like structures in their outer integument (spiracles) which allow for a periodic gas exchange pattern known as the discontinuous gas exchange cycle (DGC). The DGC facilitates the temporal decoupling of whole animal gas exchange from cellular respiration rates and may confer several physiological benefits, which are nevertheless highly controversial (primarily reduction of cellular oxidative damage and/or respiratory water saving). The intrinsic and extrinsic factors influencing DGCs are the focus of extensive ongoing research and little consensus has been reached on the evolutionary genesis or mechanistic costs and benefits of the pattern. Despite several hypotheses and much experimental and evolutionary biology research, a mechanistic physical model, which captures various key elements of the DGC pattern, is currently lacking. Here, we present a biologically realistic computational, two-sensor DGC model (pH/carbon dioxide and oxygen setpoints) for an Orthopteran gas exchange system, and show computationally for the first time that a control system of two interacting feedback loops is capable of generating a full DGC pattern with outputs which are physiologically realistic, quantitatively matching experimental results found in this taxonomic model elsewhere. A finite-element mathematical approach is employed and various trigger sets are considered. Parameter sensitivity analyses suggest that various aspects of insect DGC are adequately captured in this model. In particular, with physiologically relevant input parameters, the full DGC pattern is induced; and the phase durations, endotracheal carbon dioxide partial pressure ranges, and pH fluctuations which arise are physically realistic. The model results support the emergent property hypothesis for the existence of DGC, and indicate that asymmetric loading and off-loading (hysteresis) in one of the sensor

  9. Robust multi-objective optimization of state feedback controllers for heat exchanger system with probabilistic uncertainty

    NASA Astrophysics Data System (ADS)

    Lotfi, Babak; Wang, Qiuwang

    2013-07-01

    The performance of thermal control systems has, in recent years, improved in numerous ways due to developments in control theory and information technology. The shell-and-tube heat exchanger (STHX) is a medium where heat transfer process occurred. The accuracy of the heat exchanger depends on the performance of both elements. Therefore, both components need to be controlled in order to achieve a substantial result in the process. For this purpose, the actual dynamics of both shell and tube of the heat exchanger is crucial. In this paper, optimal reliability-based multi-objective Pareto design of robust state feedback controllers for a STHX having parameters with probabilistic uncertainties. Accordingly, the probabilities of failure of those objective functions are also considered in the reliability-based design optimization (RBDO) approach. A new multi-objective uniform-diversity genetic algorithm (MUGA) is presented and used for Pareto optimum design of linear state feedback controllers for STHX problem. In this way, Pareto front of optimum controllers is first obtained for the nominal deterministic STHX using the conflicting objective functions in time domain. Such Pareto front is then obtained for STHX having probabilistic uncertainties in its parameters using the statistical moments of those objective functions through a Hammersley Sequence Sampling (HSS) approach. It is shown that multi-objective reliability-based Pareto optimization of the robust state feedback controllers using MUGA includes those that may be obtained by various crisp threshold values of probability of failures and, thus, remove the difficulty of selecting suitable crisp values. Besides, the multi-objective Pareto optimization of such robust feedback controllers using MUGA unveils some very important and informative trade-offs among those objective functions. Consequently, some optimum robust state feedback controllers can be compromisingly chosen from the Pareto frontiers.

  10. Independent control of the shape and composition of ionic nanocrystals through sequential cation exchange reactions

    SciTech Connect

    Luther, Joseph Matthew; Zheng, Haimei; Sadtler, Bryce; Alivisatos, A. Paul

    2009-07-06

    Size- and shape-controlled nanocrystal growth is intensely researched for applications including electro-optic, catalytic, and medical devices. Chemical transformations such as cation exchange overcome the limitation of traditional colloidal synthesis, where the nanocrystal shape often reflects the inherent symmetry of the underlying lattice. Here we show that nanocrystals, with established synthetic protocols for high monodispersity, can be templates for independent composition control. Specifically, controlled interconversion between wurtzite CdS, chalcocite Cu2S, and rock salt PbS occurs while preserving the anisotropic dimensions unique to the as-synthesized materials. Sequential exchange reactions between the three sulfide compositions are driven by the disparate solubilites of the metal ion exchange pair in specific coordinating molecules. Starting with CdS, highly anisotropic PbS nanorods are created, which serve as an important material for studying strong 2-dimensional quantum confinement, as well as for optoelectronic applications. Furthermore, interesting nanoheterostructures of CdS|PbS are obtained by precise control over ion insertion and removal.

  11. Development and Evaluation of Oral Controlled Release Chlorpheniramine-Ion Exchange Resinate Suspension

    PubMed Central

    Kadam, A. U.; Sakarkar, D. M.; Kawtikwar, P. S.

    2008-01-01

    An oral controlled release suspension of chlorpheniramine maleate was prepared using ion-exchange resin technology. A strong cation exchange resin Indion 244 was utilized for the sorption of the drug and the drug resinates was evaluated for various physical and chemical parameters. The drug-resinate complex was microencapsulated with a polymer Eudragit RS 100 to further retard the release characteristics. Both the drug-resinate complex and microencapsulated drug resinate were suspended in a palatable aqueous suspension base and were evaluated for controlled release characteristic. Stability study indicated that elevated temperature did not alter the sustained release nature of the dosage form indicating that polymer membrane surrounding the core material remained intact throughout the storage period. PMID:20046790

  12. Enhancing cancer control programmatic and research opportunities for African-Americans through technical assistance training.

    PubMed

    Satcher, David; Sullivan, Louis W; Douglas, Harry E; Mason, Terry; Phillips, Rogsbert F; Sheats, Joyce Q; Smith, Selina A

    2006-10-15

    African-Americans remain severely underrepresented in cancer control program delivery and research. Community-based organizational leaders and minority junior investigators have received little attention as representatives of target populations, or as agents to deliver and evaluate efforts to eliminate cancer health disparities. This paper describes activities of the National Black Leadership Initiative on Cancer II: Network Project, which has sought to address these issues. Community leaders and junior investigators received technical assistance (TA) and mentoring to develop applications for cancer education and community-based participatory research (CBPR) projects. TA was provided to 35 community leaders and 32 junior investigators. Twenty-nine community leaders won funding through the Community Partners for Cancer Education Program. Three pilot research applications were funded. Technical assistance may improve minority recruitment/retention in CBPR cancer control research and enhance understanding and elimination of cancer health disparities among African-Americans. Cancer 2006. (c) American Cancer Society.

  13. On a Time-Optimal Control Problem Associated with the Heat Exchange Process

    SciTech Connect

    Albeverio, Sergio Alimov, Shavkat

    2008-02-15

    The initial-boundary problem for the heat conduction equation inside a bounded domain is considered. It is supposed that on the boundary of this domain the heat exchange according to Newton's law takes place. The control parameter is equal to the magnitude of output of hot or cold air and is defined on a given part of the boundary. An estimate of the minimal time for achieving the given average temperature is found.

  14. The role of cation exchange in controlling groundwater chemistry at Aspo, Sweden

    SciTech Connect

    Viani, B.E.; Bruton, C.J.

    1995-01-01

    Construction-induced groundwater flow has resulted in the mixing of relatively dilute shallow groundwater with more concentrated groundwater at depth in the underground Hard Rock Laboratory (HRL) at Aespoe, Sweden. The observed compositional variation of the mixed groundwater cannot be explained using a conservative mixing model. The geochemical modeling package EQ3/6, to which a cation-exchange model was added, was used to simulate mixing between the two fluids. The results of modeling simulations suggest that cation exchange between groundwater and fracture-lining clays can explain the major element fluid chemistry observed in the HRL. The quantity of exchanger required to match simulated with observed fluid chemistry is reasonable and is consistent with the observed fracture mineralogy. This preliminary study establishes cation exchange as a viable mechanism for controlling the chemical evolution of groundwaters in a fracture-dominated dynamic flow system. This modeling study also strengthens their confidence in the ability to model the potential effects of fracture-lining minerals on the transport of radionuclides in a high level nuclear waste repository.

  15. Controlled transdermal delivery of leuprorelin by pulsed iontophoresis and ion-exchange fiber.

    PubMed

    Malinovskaja, Kristina; Laaksonen, Timo; Hirvonen, Jouni

    2014-11-01

    Poor transport efficacy and issues related to biological variation are major concerns in the development of novel iontophoretic devices for the transdermal delivery of therapeutic peptides. The objective of this study was to examine the impact of constant and pulsed current on the transport of nonapeptide leuprorelin acetate across porcine epidermis. Also, the potential of drug delivery system combining iontophoresis and ion-exchange fibers as drug matrices for the delivery of the same peptide was tested. The present study demonstrated the benefit of pulsed current (Tn=2.59×10(-4)) over constant current (Tn=1.7×10(-4)) in terms of more efficient transdermal peptide transport. An increase in the delivery of electroosmotic marker by pulsed current was due to the combined effect of more pronounced electroosmotic transport and reduced inhibition of passive transport. We also showed a promising approach using ion-exchange fibers for controlling the release and iontophoretic transdermal delivery of peptides. Positively charged leuprorelin acetate was bound to the ion-exchange groups of cation-exchange fibers until it was gradually released by mobile counter ions in the external solution. Transdermal flux from acrylic acid grafted Smopex®-102 fibers remained higher (Jss=0.71μg/hcm(2)) than from sulfonic acid grafted Smopex®-101 fibers (Jss=0.31μg/hcm(2)) due to better drug release.

  16. A Preliminary Study: USMC Tactical Communications Technical Control Needs for the Landing Force Integrated Communications System.

    DTIC Science & Technology

    1985-09-01

    corrected thereby making the TSQ-111 a viable alternative choice for the long term . There is too little lead time and high acquisition risk (quantity...SaCUIWTY CLASSIFICATION OF THIS PAGE (hM 0a Emeee 20. long term (1991+) eras of service. Examined...are the technical control functional requirements for both the transitional near term and the eventual long term digital i systems. The study raises

  17. Coherent control of charge exchange in strong-field dissociation of LiF

    NASA Astrophysics Data System (ADS)

    Armstrong, Greg; Esry, Brett

    2016-05-01

    The alkali-metal-halides family of molecules are useful prototypes in the study of laser-assisted charge exchange. Typically these molecules possess a field-free crossing between the ionic and covalent diabatic Born-Oppenheimer potential curves, leading to Li+ + F- and Li + F in LiF. These channels are energetically well-separated from higher-lying potentials, and may be easily distinguished experimentally. Moreover, charge exchange involves non-adiabatic transitions between the ionic and covalent channels, thereby allowing the investigation of physics beyond the Born-Oppenheimer approximation. The focus of this work is to control the preference between ionic and covalent dissociative products. We solve the time-dependent Schrödinger equation for the nuclear motion in full dimensionality, and investigate a pump-probe scheme for charge-exchange control. The degree of control is investigated by calculating the kinetic-energy release spectrum as a function of pump-probe delay for the ionic and covalent fragments. This work is supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy.

  18. UMIST, IDN, NTUA, TUM, ULB: A Successful European Exchange Programme.

    ERIC Educational Resources Information Center

    Borne, Pierre; Singh, Madan G.

    1989-01-01

    Describes the exchange programs that existed for a decade in the fields of automatic control and computer science including the University of Manchester Institute of Science and Technology, the "Institut Industriel du Nord," the National Technical University of Athens, the Technical University of Munich, and the Free University of…

  19. Anion-exchange resin-based desulfurization process. Quarterly technical progress report, April 1, 1993--June 30, 1993

    SciTech Connect

    Sheth, A.C.; Dharmapurikar, R.

    1993-09-01

    Under the current grant (No. DE-FG22-90PC90309), the University of Tennessee Space Institute (UTSI) will perform the bench scale evaluation and further development of the anion-exchange resin-based desulfurization concept to desulfurize alkali metal sulfates. The developmental program proposed under this DOE grant includes screening of commercially available resins to select three candidate resins for further study. These three resins will undergo a series of experiments designed to test the resins` performance under different process conditions (including the use of spent MHD seed material). The best of these resins will be used in optimizing the regeneration step and in testing the effects of performance enhancers. During this reporting period, April 1, 1993 to June 30, 1993, the procedure to evaluate the cycle efficiency of candidate resins in the fixed-bed mode was slightly modified to ensure complete regeneration of the exhausted resin. Using this revised procedure, ten consecutive cycles for all the three resins have been completed and the results are being analyzed.

  20. Anion-exchange resin-based desulfurization process. Annual technical progress report, October 1, 1991--September 30, 1992

    SciTech Connect

    Sheth, A.C.; Strevel, S.D.; Dharmapurikar, R.

    1992-12-31

    Under the current grant, the University of Tennessee Space Institute (UTSI) will carry out the bench scale evaluation and further development of the anion-exchange resin-based desulfurization concept to desulfurize alkali metal sulfates. This concept has been developed and patented by UTSI under US Patent No. 4,917,874. The developmental program proposed under this DOE grant includes screening of commercially available resins to select three candidate resins for further study. These three resins will undergo a series of experiments designed to test the resins` performance under different process conditions (including the use of spent MHD seed material). The best of these resins will be used in optimizing the regeneration step and in testing the effects of performance enhancers. The process schematic developed from the results will be used to estimate the related economics. During this reporting period, October 1, 1991 to September 30, 1992, analysis of batch mode screening experiments was completed to select three candidate resins for process variables study in the fixed-bed set-up. This setup was modified and the experiments were carded out to evaluate effects of major process variables. The analysis of fixed-bed experiments is going on and we have also started simple batch mode experiments to identify desirable conditions for resin regeneration step. We have also started simple process engineering type calculations to determine the trade-off between the solution concentration and the resulting evaporation/concentration load.

  1. Costs and technical characteristics of environmental control processes for low-Btu coal gasification plants

    SciTech Connect

    Singh, S.P.N.; Salmon, R.; Fisher, J.F.; Peterson, G.R.

    1980-06-01

    Technical characteristics and costs of 25 individual environmental control processes that can be used for treating low-Btu coal gas are given. These processes are chosen from a much larger array of potential environmental control processes because of their likely applicability to low-Btu coal gasification operations and because of the limited scope of this study. The selected processes cover gas treating, by-product recovery, wastewater treating, and particulate recovery operations that are expected to be encountered in coal gasification operations. Although the existence of the Resource Conservtion and Recovery Act of 1976 is recognized, no treatment schemes for solid wastes are evaluated because of the paucity of information in this area. The potential costs of emission controls (by using eight integrated combinations of these 25 environmental control processes) in conceptual low-Btu coal gasification plants are given in an adjunct report titled Evaluation of Eight Environmental Control Systems for Low-Btu Coal Gasification Plants, ORNL-5481.

  2. Flight tests using data link for air traffic control and weather information exchange

    NASA Technical Reports Server (NTRS)

    Knox, Charles E.; Scanlon, Charles H.

    1990-01-01

    Message exchange for air traffic control (ATC) purposes via data link offers the potential benefits of increasing the airspace system safety and efficiency. This is accomplished by reducing communication errors and relieving the overloaded ATC radio frequencies, which hamper efficient message exchanges during peak traffic periods in many busy terminal areas. However, the many uses and advantages of data link create additional questions concerning the interface among the human-users and the cockpit and ground systems. A flight test was conducted in the NASA Langley B-737 airplane to contrast flight operations using current voice communications with the use of data link for transmitting both strategic and tactical ATC clearances during a typical commercial airline flight from takeoff to landing. Commercial airplane pilots were used as test subjects.

  3. Flight tests with a data link used for air traffic control information exchange

    NASA Technical Reports Server (NTRS)

    Knox, Charles E.; Scanlon, Charles H.

    1991-01-01

    Previous studies showed that air traffic control (ATC) message exchange with a data link offers the potential benefits of increased airspace system safety and efficiency. To accomplish these benefits, data link can be used to reduce communication errors and relieve overloaded ATC voice radio frequencies, which hamper efficient message exchange during peak traffic periods. Flight tests with commercial airline pilots as test subjects were conducted in the NASA Transport Systems Research Vehicle Boeing 737 airplane to contrast flight operations that used current voice communications with flight operations that used data link to transmit both strategic and tactical ATC clearances during a typical commercial airflight from takeoff to landing. The results of these tests that used data link as the primary communication source with ATC showed flight crew acceptance, a perceived reduction in crew work load, and a reduction in crew communication errors.

  4. Controlled exchange interaction between pairs of neutral atoms in an optical lattice.

    PubMed

    Anderlini, Marco; Lee, Patricia J; Brown, Benjamin L; Sebby-Strabley, Jennifer; Phillips, William D; Porto, J V

    2007-07-26

    Ultracold atoms trapped by light offer robust quantum coherence and controllability, providing an attractive system for quantum information processing and for the simulation of complex problems in condensed matter physics. Many quantum information processing schemes require the manipulation and deterministic entanglement of individual qubits; this would typically be accomplished using controlled, state-dependent, coherent interactions among qubits. Recent experiments have made progress towards this goal by demonstrating entanglement among an ensemble of atoms confined in an optical lattice. Until now, however, there has been no demonstration of a key operation: controlled entanglement between atoms in isolated pairs. Here we use an optical lattice of double-well potentials to isolate and manipulate arrays of paired (87)Rb atoms, inducing controlled entangling interactions within each pair. Our experiment realizes proposals to use controlled exchange coupling in a system of neutral atoms. Although 87Rb atoms have nearly state-independent interactions, when we force two atoms into the same physical location, the wavefunction exchange symmetry of these identical bosons leads to state-dependent dynamics. We observe repeated interchange of spin between atoms occupying different vibrational levels, with a coherence time of more than ten milliseconds. This observation demonstrates the essential component of a neutral atom quantum SWAP gate (which interchanges the state of two qubits). Its 'half-implementation', the root SWAP gate, is entangling, and together with single-qubit rotations it forms a set of universal gates for quantum computation.

  5. Magnetoelectric thin films for electrically controlled exchange bias in spintronic applications

    NASA Astrophysics Data System (ADS)

    He, Xi; Sahoo, Sarbeswar; Polisetty, Srinivas; Wang, Yi; Mukherjee, Tathagata; Binek, Christian

    2007-03-01

    Epitaxial (111) oriented thin films of magnetoelectric (ME) Cr2O3 are grown by MBE. These films are the key component of Cr2O3(111)/(Co/Pt)3 heterostructures allowing for electrically controlled exchange bias (EB) and novel spintronic applications [1]. Pure voltage control of magnetic configurations in TMR-type devices is proposed as an alternative to current-induced switching. Basic effects of electrically controlled EB and its ME switching are studied by magnetometry and polar Kerr rotation. Exchange coupling between the ME antiferromagnet Cr2O3 and the ferromagnetic CoPt multilayer gives rise to perpendicular EB. The latter is controlled by axial electric fields inducing excess magnetization at the interface which controlls the EB field. Recently, the sign of the EB field has been tuned via a field cooling procedure where a Cr2O3(111) bulk/(Co/Pt)3 system is exposed to either parallel or antiparallel axial magnetic and electric fields [2]. Here we study this ME switching effect in an all thin film heterostructure. [1] Ch.Binek, B.Doudin, J. Phys. Condens. Matter 17, L39 (2005). [2] P.Borisov et al., Phys. Rev. Lett. 94, 117203 (2005).

  6. Feasible way of Human Solid and Liquid Wastes' Inclusion Into Intersystem Mass Exchange of Biological-Technical Life Support Systems

    NASA Astrophysics Data System (ADS)

    Ushakova, Sofya; Tikhomirov, Alexander A.; Tikhomirova, Natalia; Kudenko, Yurii; Griboskaya, Illiada; Gros, Jean-Bernard; Lasseur, Christophe

    The basic objective arising at use of mineralized human solid and liquid wastes serving as the source of mineral elements for plants cultivation in biological-technical life support systems appears to be NaCl presence in them. The given work is aimed at feasibility study of mineralized human metabolites' utilization for nutrient solutions' preparation for their further employment at a long-term cultivation of uneven-aged wheat and Salicornia europaea L. cenosis in a conveyer regime. Human solid and liquid wastes were mineralized by the "wet incineration" method developed by Yu. Kudenko. On their base the solutions were prepared which were used for cultivation of 5-aged wheat conveyer with the time step-interval of 14 days. Wheat was cultivated by hydroponics method on expanded clay aggregate. For partial demineralization of nutrient solution every two weeks after regular wheat harvesting 12 L of solution was withdrawn from the wheat irrigation tank and used for Salicornia europaea cultivation by the water culture method in a conveyer regime. The Salicornia europaea conveyer was represented by 2 ages with the time step-interval of 14 days. Resulting from repeating withdrawal of the solution used for wheat cultivation, sodium concentration in the wheat irrigation solution did not exceed 400 mg/l, and mineral elements contained in the taken solution were used for Salicornia europaea cultivation. The experiment lasted 7 months. Total wheat biomass productivity averaged 30.1 g*m-2*day-1 at harvest index equal to 36.8The work was carried out under support of SB RAS grant 132 and INTAS 05-1000008-8010

  7. Coordinated control of volume regulatory Na+/H+ and K+/H+ exchange pathways in Amphiuma red blood cells

    PubMed Central

    Rigor, Robert R.; Maldonado, Hector M.; Cala, Peter M.

    2010-01-01

    The Na+/H+ and K+/H+ exchange pathways of Amphiuma tridactylum red blood cells (RBCs) are quiescent at normal resting cell volume yet are selectively activated in response to cell shrinkage and swelling, respectively. These alkali metal/H+ exchangers are activated by net kinase activity and deactivated by net phosphatase activity. We employed relaxation kinetic analyses to gain insight into the basis for coordinated control of these volume regulatory ion flux pathways. This approach enabled us to develop a model explaining how phosphorylation/dephosphorylation-dependent events control and coordinate the activity of the Na+/H+ and K+/H+ exchangers around the cell volume set point. We found that the transition between initial and final steady state for both activation and deactivation of the volume-induced Na+/H+ and K+/H+ exchange pathways in Amphiuma RBCs proceed as a single exponential function of time. The rate of Na+/H+ exchange activation increases with cell shrinkage, whereas the rate of Na+/H+ exchange deactivation increases as preshrunken cells are progressively swollen. Similarly, the rate of K+/H+ exchange activation increases with cell swelling, whereas the rate of K+/H+ exchange deactivation increases as preswollen cells are progressively shrunken. We propose a model in which the activities of the controlling kinases and phosphatases are volume sensitive and reciprocally regulated. Briefly, the activity of each kinase-phosphatase pair is reciprocally related, as a function of volume, and the volume sensitivities of kinases and phosphatases controlling K+/H+ exchange are reciprocally related to those controlling Na+/H+ exchange. PMID:19940069

  8. Nonlinear robust control of proton exchange membrane fuel cell by state feedback exact linearization

    NASA Astrophysics Data System (ADS)

    Li, Q.; Chen, W.; Wang, Y.; Jia, J.; Han, M.

    By utilizing the state feedback exact linearization approach, a nonlinear robust control strategy is designed based on a multiple-input multiple-output (MIMO) dynamic nonlinear model of proton exchange membrane fuel cell (PEMFC). The state feedback exact linearization approach can achieve the global exact linearization via the nonlinear coordinate transformation and the dynamic extension algorithm such that H ∞ robust control strategy can be directly utilized to guarantee the robustness of the system. The proposed dynamic nonlinear model is tested by comparing the simulation results with the experimental data in Fuel Cell Application Centre in Temasek Polytechnic. The comprehensive results of simulation manifest that the dynamic nonlinear model with nonlinear robust control law has better transient and robust stability when the vehicle running process is simulated. The proposed nonlinear robust controller will be very useful to protect the membrane damage by keeping the pressure deviations as small as possible during large disturbances and prolong the stack life of PEMFC.

  9. Ultrafast and reversible control of the exchange interaction in Mott insulators

    PubMed Central

    Mentink, J. H.; Balzer, K.; Eckstein, M.

    2015-01-01

    The strongest interaction between microscopic spins in magnetic materials is the exchange interaction Jex. Therefore, ultrafast control of Jex holds the promise to control spins on ultimately fast timescales. We demonstrate that time-periodic modulation of the electronic structure by electric fields can be used to reversibly control Jex on ultrafast timescales in extended antiferromagnetic Mott insulators. In the regime of weak driving strength, we find that Jex can be enhanced and reduced for frequencies below and above the Mott gap, respectively. Moreover, for strong driving strength, even the sign of Jex can be reversed and we show that this causes time reversal of the associated quantum spin dynamics. These results suggest wide applications, not only to control magnetism in condensed matter systems, for example, via the excitation of spin resonances, but also to assess fundamental questions concerning the reversibility of the quantum many-body dynamics in cold atom systems. PMID:25819547

  10. Fiber-optic, anti-cycling, high pressure sodium street light control. Final technical progress report

    SciTech Connect

    1995-05-01

    This is the Final Technical Progress Report on a project to develop and market a Fiber-Optic Anti-Cycling High Pressure Sodium Street Light Control. The field test units are now being made with a single vertical PC board design and contains a computer-on-a-chip or PROM IC to take the place of the majority of the components previously contained on the upper logic board. This will reduce the final costs of the unit when it is in production and increase the control`s flexibility. The authors have finished the soft tooling and have made the 400 plastic cases for the field test units. The new configuration of the cases entails a simplified design of the control shell which will have the lenses cast in place. The shell and base plastics are now finished and in final assembly awaiting the completion of the PC boards.

  11. Technical Requirements Analysis and Control Systems (TRACS) Initial Operating Capability (IOC) documentation

    NASA Technical Reports Server (NTRS)

    Hammond, Dana P.

    1991-01-01

    The Technical Requirements Analysis and Control Systems (TRACS) software package is described. TRACS offers supplemental tools for the analysis, control, and interchange of project requirements. This package provides the fundamental capability to analyze and control requirements, serves a focal point for project requirements, and integrates a system that supports efficient and consistent operations. TRACS uses relational data base technology (ORACLE) in a stand alone or in a distributed environment that can be used to coordinate the activities required to support a project through its entire life cycle. TRACS uses a set of keyword and mouse driven screens (HyperCard) which imposes adherence through a controlled user interface. The user interface provides an interactive capability to interrogate the data base and to display or print project requirement information. TRACS has a limited report capability, but can be extended with PostScript conventions.

  12. Low-energy magnetoelectric control of domain states in exchange-coupled heterostructures

    NASA Astrophysics Data System (ADS)

    Al-Mahdawi, Muftah; Pati, Satya Prakash; Shiokawa, Yohei; Ye, Shujun; Nozaki, Tomohiro; Sahashi, Masashi

    2017-04-01

    The electric manipulation of antiferromagnets has become an area of great interest recently for zero-stray-field spintronic devices, and for their rich spin dynamics. Generally, the application of antiferromagnetic media for information memories and storage requires a heterostructure with a ferromagnetic layer for readout through the exchange-bias field. In magnetoelectric and multiferroic antiferromagnets, the exchange coupling exerts an additional impediment (energy barrier) to magnetization reversal by the applied magnetoelectric energy. We proposed and verified a method to overcome this barrier. We controlled the energy required for switching the magnetic domains in magnetoelectric Cr2O3 films by compensating the exchange-coupling energy from the ferromagnetic layer with the Zeeman energy of a small volumetric spontaneous magnetization found for the sputtered Cr2O3 films. Based on a simplified phenomenological model of the field-cooling process, the magnetic and electric fields required for switching could be tuned. As an example, the switching of antiferromagnetic domains around a zero-threshold electric field was demonstrated at a magnetic field of 2.6 kOe.

  13. Thermal control of a lidar laser system using a non-conventional ram air heat exchanger

    NASA Technical Reports Server (NTRS)

    Killough, Brian D.; Alexander, William, Jr.; Swofford, Doyle P.

    1990-01-01

    This paper describes the analysis and performance testing of a uniquely designed external heat exchanger. The heat exchanger is attached externally to an aircraft and is used to cool a laser system within the fuselage. Estimates showed insufficient cooling capacity with a conventional staggered tube array in the limited space available. Thus, a non-conventional design wes developed with larger tube and fin area exposed to the ram air to increase the heat transfer performance. The basic design consists of 28 circular finned aluminum tubes arranged in two parallel banks. Wind tunnel tests were performed to simulate air and liquid flight conditions for the non-conventional parallel bank arrangement and the conventional staggered tube arrangement. Performance comparisons of each of the two designs are presented. Test results are used in a computer model of the heat exchanger to predict the operating performance for the entire flight profile. These analyses predict significantly improved performance over the conventional design and show adequate thermal control margins.

  14. Thermal control of a lidar laser system using a non-conventional ram air heat exchanger

    NASA Technical Reports Server (NTRS)

    Killough, Brian D.; Alexander, William, Jr.; Swofford, Doyle P.

    1990-01-01

    This paper describes the analysis and performance testing of a uniquely designed external heat exchanger. The heat exchanger is attached externally to an aircraft and is used to cool a laser system within the fuselage. Estimates showed insufficient cooling capacity with a conventional staggered tube array in the limited space available. Thus, a non-conventional design wes developed with larger tube and fin area exposed to the ram air to increase the heat transfer performance. The basic design consists of 28 circular finned aluminum tubes arranged in two parallel banks. Wind tunnel tests were performed to simulate air and liquid flight conditions for the non-conventional parallel bank arrangement and the conventional staggered tube arrangement. Performance comparisons of each of the two designs are presented. Test results are used in a computer model of the heat exchanger to predict the operating performance for the entire flight profile. These analyses predict significantly improved performance over the conventional design and show adequate thermal control margins.

  15. Controls on residence time and exchange in a system of shallow coastal bays

    NASA Astrophysics Data System (ADS)

    Safak, I.; Wiberg, P. L.; Richardson, D. L.; Kurum, M. O.

    2015-04-01

    Patterns of transport and residence time influence the morphology, ecology and biogeochemistry of shallow coastal bay systems in important ways. To better understand the factors controlling residence time and exchange in coastal bays, a three-dimensional finite-volume coastal ocean model was set up and validated with field observations of circulation in a system of 14 shallow coastal bays on the Atlantic coast of the USA (Virginia Coast Reserve). Residence times of neutrally buoyant particles as well as exchange among the bays in the system and between the bays and the ocean were examined with Lagrangian particle tracking. There was orders of magnitude variation in the calculated residence time within most of the bays, ranging from hours in the tidally refreshed (repletion) water near the inlets to days-weeks in the remaining (residual) water away from the inlets. Residence time in the repletion waters was most sensitive to the tidal phase (low vs. high) when particles were released whereas residence time in the residual waters was more sensitive to wind forcing. Wind forcing was found to act as a diffuser that shortens particle residence within the bays; its effect was higher away from the inlets and in relatively confined bays. Median residence time in the bays significantly decreased with an increase in the ratio between open water area and total area (open water plus marsh). Exchange among the bays and capture areas of inlets (i.e., exchange between the bays and the ocean) varied considerably but were insensitive to tidal phase of release, wind, and forcing conditions in different years, in contrast to the sensitivity of residence time to these factors. We defined a new quantity, termed shortest-path residence time, calculated as distance from the closest inlet divided by root-mean-square velocity at each point in model domain. A relationship between shortest-path residence time and particle-tracking residence time provides a means of estimating residence time

  16. Multiple model predictive control for a hybrid proton exchange membrane fuel cell system

    NASA Astrophysics Data System (ADS)

    Chen, Qihong; Gao, Lijun; Dougal, Roger A.; Quan, Shuhai

    This paper presents a hierarchical predictive control strategy to optimize both power utilization and oxygen control simultaneously for a hybrid proton exchange membrane fuel cell/ultracapacitor system. The control employs fuzzy clustering-based modeling, constrained model predictive control, and adaptive switching among multiple models. The strategy has three major advantages. First, by employing multiple piecewise linear models of the nonlinear system, we are able to use linear models in the model predictive control, which significantly simplifies implementation and can handle multiple constraints. Second, the control algorithm is able to perform global optimization for both the power allocation and oxygen control. As a result, we can achieve the optimization from the entire system viewpoint, and a good tradeoff between transient performance of the fuel cell and the ultracapacitor can be obtained. Third, models of the hybrid system are identified using real-world data from the hybrid fuel cell system, and models are updated online. Therefore, the modeling mismatch is minimized and high control accuracy is achieved. Study results demonstrate that the control strategy is able to appropriately split power between fuel cell and ultracapacitor, avoid oxygen starvation, and so enhance the transient performance and extend the operating life of the hybrid system.

  17. Command Generation and Control of Momentum Exchange Electrodynamic Reboost Tethered Satellite

    NASA Technical Reports Server (NTRS)

    Robertson, Michael J.

    2005-01-01

    The research completed for this NASA Graduate Student Research Program Fellowship sought to enhance the current state-of-the-art dynamic models and control laws for Momentum Exchange Electrodynamic Reboost satellite systems by utilizing command generation, specifically Input Shaping. The precise control of tethered spacecraft with flexible appendages is extremely difficult. The complexity is magnified many times when the satellite must interact with other satellites as in a momentum exchange via a tether. The Momentum Exchange Electronic Reboost Tether (MXER) concept encapsulates all of these challenging tasks [l]. Input Shaping is a command generation technique that allows flexible spacecraft to move without inducing residual vibration [2], limit transient deflection [3] and utilize fuel-efficient actuation [4]. Input shaping is implemented by convolving a sequence of impulses, known as the input shaper, with a desired system command to produce a shaped input that is then used to drive the system. This process is demonstrated in Figure 1. The shaped command is then use to drive the system without residual vibration while meeting many other performance specifications. The completed work developed tether control algorithms for retrieval. A simple model of the tether response has been developed and command shaping was implemented to minimize unwanted dynamics. A model of a flexible electrodynamic tether has been developed to investigate the tether s response during reboost. Command shaping techniques have been developed to eliminate the tether oscillations and reduce the tether s deflection to pre-specified levels during reboost. Additionally, a model for the spin-up of a tethered system was developed. This model was used in determining the parameters for optimization the resulting angular velocity.

  18. Controlling plasmonic "hot spots" in nanoparticle assemblies using ligand place-exchange reactions

    NASA Astrophysics Data System (ADS)

    Bao, Lanlan

    properties of the Au nanoplate-Au NP assemblies were studied by monitoring the shift in the LSPR band of the Au nanoplates upon attachment of Au NPs and by measuring the SERS enhancement of the 4-ATP linker. The LSPR band red shifted about 1 nm upon attachment of each Au NP at the vertex and edge sites. The estimated shift is about 0.1 to 0.6 nm per Au NP for those attached to the terraces sites, where the shift is larger for Au NPs attached to outer terrace sites close to the edge and smaller for the inner terrace sites. Au nanoplate-Au NP assemblies with 100% of the NPs attached on the vertex sites of the nanoplates showed the largest enhancement relative to the Au nanoplates. The intensity was similar to the assemblies with many more NPs, but relatively fewer at the vertex/edge sites, indicating that the "hottest spot" for enhancement is located in the interparticle junction between the vertex of the nanoplate and the attached NP. The relative enhancement of the Au nanoplate-Au NP couple relative to the Au nanoplate alone was about 11 on a per Au NP basis. Fundamentally, the results suggest that a small number of "hottest spots" in the laser beam area dominate the Raman enhancement signal and practically, the nanoplate-NP coupling approach controllably at the vertex/edge sites can be very useful for amplifying the detection of analyte down to the single molecule level. This research provides a simple approach for the preparation of various nanostructure assemblies with high accuracy and reproducibility. At the same time, it can potentially be used to control the location of analyte for LSPR and SERS sensing. Another important contribution of this study is the direct evidence for the mechanism and kinetics of the ligand place-exchange reaction on the nanoplate surfaces, which can be useful for controlling NP attachment to other structures as well.

  19. Electrical control of exchange bias via oxygen migration across CoO-ZnO nanocomposite barrier

    NASA Astrophysics Data System (ADS)

    Li, Q.; Yan, S. S.; Xu, J.; Li, S. D.; Zhao, G. X.; Long, Y. Z.; Shen, T. T.; Zhang, K.; Zhang, J.

    2016-12-01

    We proposed a nanocomposite barrier CoO-ZnO for magnetism manipulation in Co/CoO-ZnO/Ag heterojunctions. Both electrical control of magnetism and resistive switching were realized in this junction. An electrical tunable exchange bias of CoO1-v (v denotes O vacancies) on Co films was realized using voltages below 1 volt. The magnetism modulation associated with resistive switching can be attributed to the oxygen ions migration between the insulating CoO1-v layer and the semiconductive ZnO1-v layer, which can cause both ferromagnetic phase and resistance switching of CoO1-v layer.

  20. Controlling the nonequilibrium interlayer exchange coupling in asymmetric magnetic tunnel junctions.

    PubMed

    Tang, Y-H; Kioussis, Nicholas; Kalitsov, Alan; Butler, W H; Car, Roberto

    2009-07-31

    We predict an oscillatory bias behavior of the fieldlike spin torque, T(perpendicular), in magnetic tunnel junctions, which can be selectively controlled via the asymmetry in band filling between the ferromagnetic leads. This can lead to a linear or quadratic low-bias behavior, including tuning the bias-induced reversal of T(perpendicular). These findings reconcile the apparently contradictory experimental results recently reported in the literature. The underlying mechanism for the nonequilibrium interlayer exchange coupling (IEC) of noncollinear configurations is the interplay of four independent IEC for the majority- and minority-spin bands of the leads solely in the ferromagnetic configuration.

  1. Eliminating leakage current in voltage-controlled exchange-bias devices

    NASA Astrophysics Data System (ADS)

    Mahmood, Ather; Echtenkamp, Will; Street, Michael; Binek, Christian; Magnetic Heterostructures Team

    Manipulation of magnetism by electric field has drawn much attention due to the technological importance for low-power devices, and for understanding fundamental magnetoelectric phenomena. A manifestation of electrically controlled magnetism is voltage control of exchange bias (EB). Robust isothermal voltage control of EB was demonstrated near room temperature using a heterostructure of Co/Pd thin film and an exchange coupled single crystal of the antiferromagnetic Cr2O3 (Chromia). A major obstacle for EB in lithographically patterned Chromia based thin-film devices is to minimize the leakage currents at high electric fields (>10 kV/mm). By combining electrical measurements on patterned devices and conductive Atomic Force Microscopy of Chromia thin-films, we investigate the defects which form conducting paths impeding the application of sufficient voltage for demonstrating the isothermal EB switching in thin film heterostructures. Technological challenges in the device fabrication will be discussed. This project was supported by SRC through CNFD, an SRC-NRI Center, by C-SPIN, part of STARnet, and by the NSF through MRSEC Abstract DMR-0820521.

  2. [Technical complications rates and plaque control of fixed dental prostheses in patients treated for periodontal disease].

    PubMed

    Xie, Yesi; Meng, Huanxin; Han, Jie; Pan, Shaoxia; Zhang, Li; Shi, Dong

    2016-02-01

    To compare the incidence of technical complications of implant-supported fixed dental prostheses in Chinese patients with a history of moderate or severe periodontitis and periodontally healthy patients(PHP) and analyze the effects of interproximal papillae patterns on food impaction and efficacy of plaque control. A total of 103 partially edentulous patients treated with implant-supported fixed dental prostheses between December 2009 and December 2012 for a minimum 1-year follow-up period were recruited from Department of Periodontology, Peking University, School and Hospital of Stomatology. Based on the initial periodontal examination, the participants were divided into three groups: 30 PHP, 36 moderate periodontally compromised patients(mPCP) and 37 severe periodontally compromised patients(sPCP). Implant survival/loss, technical complications, plaque index, papilla index, food impaction and degree of proximal contact tightness of each patient were assessed around the implants at follow-up. According to the implant papilla index, the implants were divided into two groups: the "filling" group with the mesial and distal aspects with papilla index=3 and the "no filling" group with at least one aspect with papilla index<3. Data on implant survival, technical complications were analyzed. Comparisons of the incidence of technical complications were performed between the patients with different periodontal conditions with chi-square or Fisher's exact test. The influences of the interproximal papillae loss on food impaction and efficacy of plaque control were estimated with chi-square and Mann-Whitney U tests. The total implant survival rate was 100%(162/162) for all three groups. Technical complications were as following: veneer fractures(1.9%, 3/162), abutment screw loosening(1.9%, 3/162), prosthetic screw loosening(3.1%, 5/162) and decementation(3.1%, 5/162) in all subjects. No implant/screw fracture was noted. The incidence of technical complications in sPCP, m

  3. Controlling Self-Assembly Kinetics of DNA-Functionalized Liposomes Using Toehold Exchange Mechanism.

    PubMed

    Parolini, Lucia; Kotar, Jurij; Di Michele, Lorenzo; Mognetti, Bortolo M

    2016-02-23

    The selectivity of Watson-Crick base pairing has allowed the design of DNA-based functional materials bearing an unprecedented level of accuracy. Examples include DNA origami, made of tiles assembling into arbitrarily complex shapes, and DNA coated particles featuring rich phase behaviors. Frequently, the realization of conceptual DNA-nanotechnology designs has been hampered by the lack of strategies for effectively controlling relaxations. In this article, we address the problem of kinetic control on DNA-mediated interactions between Brownian objects. We design a kinetic pathway based on toehold-exchange mechanisms that enables rearrangement of DNA bonds without the need for thermal denaturation, and test it on suspensions of DNA-functionalized liposomes, demonstrating tunability of aggregation rates over more than 1 order of magnitude. While the possibility to design complex phase behaviors using DNA as a glue is already well recognized, our results demonstrate control also over the kinetics of such systems.

  4. Rotational Control of a Dirhodium-Centered Supramolecular Four-Gear System by Ligand Exchange.

    PubMed

    Sanada, Kazuma; Ube, Hitoshi; Shionoya, Mitsuhiko

    2016-03-09

    Self-assembled molecular machines have great potential to enable noncovalent regulation of a coupled motion of the building blocks. Herein we report the synthesis and the rotational control of a lantern-type dirhodium complex with circularly arranged four 2,3,6,7,14,15-hexamethyltriptycene carboxylates as gears and two axial ligands as the rate control elements. The rotating rates in solution were markedly affected by the coordination ability and the bulkiness of axial ligands. Notably, the rate changes were closely correlated with the changes in the electronic states of the dirhodium center. Such ligand exchange-based control of rotational motions with color changes would advance stimulus-responsive metallo-molecular multirotors.

  5. Multivariable robust control of a proton exchange membrane fuel cell system

    NASA Astrophysics Data System (ADS)

    Wang, Fu-Cheng; Chen, Hsuan-Tsung; Yang, Yee-Pien; Yen, Jia-Yush

    This paper applies multivariable robust control strategies to a proton exchange membrane fuel cell (PEMFC) system. From the system point of view, a PEMFC can be modeled as a two-input-two-output system, where the inputs are air and hydrogen flow rates and the outputs are cell voltage and current. By fixing the output resistance, we aimed to control the cell voltage output by regulating the air and hydrogen flow rates. Due to the nonlinear characteristics of this system, multivariable robust controllers were designed to provide robust performance and to reduce the hydrogen consumption of this system. The study was carried out in three parts. Firstly, the PEMFC system was modeled as multivariable transfer function matrices using identification techniques, with the un-modeled dynamics treated as system uncertainties and disturbances. Secondly, robust control algorithms were utilized to design multivariable H ∞ controllers to deal with system uncertainty and performance requirements. Finally, the designed robust controllers were implemented to control the air and hydrogen flow rates. From the experimental results, multivariable robust control is shown to provide steady output responses and significantly reduce hydrogen consumption.

  6. Admittance control of an upper limb exoskeleton--reduction of energy exchange.

    PubMed

    Kim, Hyunchul; Miller, Levi Makaio; Li, Zhi; Roldan, Jay Ryan; Rosen, Jacob

    2012-01-01

    The synergy of human arms and wearable robot systems (e.g. exoskeletons) is enabled by a control algorithm that maximizes the transparency between the two subsystems. The transparency can be improved by integrating the admittance control along with an arm redundancy resolution algorithm. Recent research effort resulted in a new criterion for the human arm redundancy resolution for unconstrained arm motions estimating the swivel angle with prediction errors of less than 5°. The proposed criterion for the arm redundancy resolution defines the mouth as the primary target of the the human hand during unconstrained arm motions in free space. It was postulated based on experimental data analysis that this criterion is based on a neural mechanism directing the hand towards the head for self-feeding. In conjunction with the proposed redundancy resolution criteria a task space admittance control algorithm is introduced based on multiple force sensor inputs obtained at the interface between the human arm and the exoskeleton system. The system performance was evaluated by five healthy subjects performing a peg-in-hole task for three different target locations. The velocities and interaction forces at the upper arm, lower arm, handle and tip were recorded and further used to power exchange between the subject and the device. Results indicated that the proposed control scheme outperforms the purely reactive task space admittance control with energy exchange reduced to 11.22%. Improving the quality of the human control of a wearable robot system may allow the robot to be a natural and transparent extension of the operator's body.

  7. Comparison of model-based and conventional controllers on a pilot-scale heat exchanger.

    PubMed

    Raul, Pramod R; Srinivasan, Haritha; Kulkarni, Sanket; Shokrian, Mazdak; Shrivastava, Glory; Russell Rhinehart, R

    2013-05-01

    This pilot-scale heat exchanger demonstration compares two relatively simple nonlinear model-based control strategies to conventional proportional-integral (PI) control. The two nonlinear controllers, generic model control (GMC) and process-model based control (PMBC), use a first-principles model thereby providing characterization of the nonlinear process throughout the operating range. There are two approaches to GMC, one uses a dynamic model, the other a steady-state model. This work uses the steady-state model; accordingly, will use the term GMC-SS, which can be classified as output characterization for a PI controller, making it relatively simple to implement. PMBC uses a dynamic model and adapts to represent the process. These two nonlinear controllers were selected for this application evaluation because of their simplicity (they can be implemented in-house within many commercial control systems), diversity (steady-state and dynamic models), and demonstrated utility for control of nonlinear single-input-single-output processes. The application and results are presented and discussed. Summarizing the results: Within a small temperature operating range PI provides good control, but over the full operating range, the nonlinear and variable delay of the process lead to poor control with PI. GMC can handle the nonlinear issues, but using the convenient steady-state model; it also, provides poor control because of the variable delay associated with flow rate. PMBC was able to provide good control throughout the entire operating range. PMBC has a further advantage of only having one tuning coefficient, while PI and GMC-SS have two.

  8. Stomatal control of gas-exchange is related to assimilate transport from leaves

    NASA Astrophysics Data System (ADS)

    Nikinmaa, E.; Holtta, T.; Sevanto, S.; Makela, A.; Hari, P.; Vesala, T.

    2009-04-01

    In land plants, the carbon fluxes are closely associated with those of water. The loss of water from leaves pulls water from soil in plants. High transpiration relative to compensating water flux from soil increases the tension of water column that may lead to its rupture and catastrophic dysfunction of the xylem if the transpiration rate is not regulated. Modification of the size of stomatal openings in leaves regulates the interconnected fluxes of water and carbon. Stomatal regulation of transpiration has direct influence also on the carbon transport from source leaves to sinks. Under given conditions, the water tension of xylem in leaves is linearly related to stomatal conductance while the assimilation rate, which is linked to the loading capacity, has saturating relationship with stomatal conductance. High sugar loading at source could compensate for the high water tension in xylem resulting from eg. high transpiration. However, excessive loading rate of the most commonly transported sugar, sucrose, causes rapid viscosity build up that effectively blocks the phloem transport. Assimilate transport from the shoot is a clear requirement for continuous photosynthetic production in leaves. Without transport the storage capacity of the leaves would be rapidly exhausted and accumulation of excess sugars in leaves lead to downregulation of photosynthesis. In this presentation we study the stomatal response to environment and its linkage to xylem and phloem tranport with dynamic model. We hypothesize that stomatal reaction to environment would maintain maximal assimilate transport in phloem under those conditions. We added to the xylem phloem transport model stomatal control of leaf gas-exchange, light and CO2 concentration dependent photosynthesis rate and carbon storage in leaf. For each time step we varied the stomatal conductance and selected the sollution that maximised the transport of assimilates in phloem. Our hypothesis reproduced realistically stomatal

  9. Plant physiological and environmental controls over the exchange of acetaldehyde between forest canopies and the atmosphere

    NASA Astrophysics Data System (ADS)

    Jardine, K.; Harley, P.; Karl, T.; Guenther, A.; Lerdau, M.; Mak, J. E.

    2008-11-01

    We quantified fine scale sources and sinks of gas phase acetaldehyde in two forested ecosystems in the US. During the daytime, the upper canopy behaved as a net source while at lower heights, reduced emission rates or net uptake were observed. At night, uptake generally predominated throughout the canopies. Net ecosystem emission rates were inversely related to foliar density due to the extinction of light in the canopy and a respective decrease of the acetaldehyde compensation point. This is supported by branch level studies revealing much higher compensation points in the light than in the dark for poplar (Populus deltoides) and holly oak (Quercus ilex) implying a higher light/temperature sensitivity for acetaldehyde production relative to consumption. The view of stomata as the major pathway for acetaldehyde exchange is supported by strong linear correlations between branch transpiration rates and acetaldehyde exchange velocities for both species. In addition, natural abundance carbon isotope analysis of gas-phase acetaldehyde during poplar branch fumigation experiments revealed a significant kinetic isotope effect of 5.1±0.3‰ associated with the uptake of acetaldehyde. Similar experiments with dry dead poplar leaves showed no fractionation or uptake of acetaldehyde, confirming that this is only a property of living leaves. We suggest that acetaldehyde belongs to a potentially large list of plant metabolites where stomatal resistance can exert long term control over both emission and uptake rates due to the presence of both source(s) and sink(s) within the leaf which strongly buffer large changes in concentrations in the substomatal airspace due to changes in stomatal resistance. We conclude that the exchange of acetaldehyde between plant canopies and the atmosphere is fundamentally controlled by ambient acetaldehyde concentrations, stomatal resistance, and the compensation point which is a function of light/temperature.

  10. Plant physiological and environmental controls over the exchange of acetaldehyde between forest canopies and the atmosphere

    NASA Astrophysics Data System (ADS)

    Jardine, K.; Harley, P.; Karl, T.; Guenther, A.; Lerdau, M.; Mak, J. E.

    2008-06-01

    We quantified fine scale sources and sinks of gas phase acetaldehyde in two forested ecosystems in the US. During the daytime, the upper canopy behaved as a net source while at lower heights, reduced emission rates or net uptake were observed. At night, uptake generally predominated thoughout the canopies. Net ecosystem emission rates were inversely related to foliar density which influenced the extinction of light and the acetaldehyde compensation point in the canopy. This is supported by branch level studies revealing much higher compensation points in the light than in the dark for poplar (Populus deltoides) and holly oak (Quercus ilex) implying a higher light/temperature sensitivity for acetaldehyde production relative to consumption. The view of stomata as the major pathway for acetaldehyde exchange is supported by strong linear correlations between branch transpiration rates and acetaldehyde exchange velocities for both species. In addition, natural abundance carbon isotope analysis of gas-phase acetaldehyde during poplar branch fumigation experiments revealed a significant kinetic isotope effect of 5.1±0.3‰, associated with the uptake of acetaldehyde. Similar experiments with dry dead poplar leaves showed no fractionation or uptake of acetaldehyde, confirming that this is only a property of living leaves. We suggest that acetaldehyde belongs to a potentially large list of plant metabolites where stomatal conductance can exert long term control over both emission and uptake rates due to the presence of both source(s) and sink(s) within the leaf which strongly buffer large changes in concentrations in the substomatal airspace due to changes in stomatal conductance. We conclude that the exchange of acetaldehyde between plant canopies and the atmosphere is fundamentally controlled by ambient acetaldehyde concentrations, stomatal conductance, and the acetaldehyde compensation point.

  11. Production, review, and impact of technical quality control guidelines in a national context.

    PubMed

    Nielsen, Michelle K; Malkoske, Kyle E; Brown, Erika; Diamond, Kevin; Frenière, Normand; Grant, John; Pomerleau-Dalcourt, Natalie; Schella, Jason; Schreiner, L John; Tantôt, Laurent; Villarreal-Barajas, J Eduardo; Bissonnette, Jean-Pierre

    2016-11-01

    A close partnership between the Canadian Partnership for Quality Radiotherapy (CPQR) and the Canadian Organization of Medical Physicist's (COMP) Quality Assurance and Radiation Safety Advisory Committee (QARSAC) has resulted in the development of a suite of Technical Quality Control (TQC) guidelines for radiation treatment equipment; they outline specific performance objectives and criteria that equipment should meet in order to assure an acceptable level of radiation treatment quality. The adopted framework for the development and maintenance of the TQCs ensures the guidelines incorporate input from the medical physics community during development, measures the workload required to perform the QC tests outlined in each TQC, and remain relevant (i.e., "living documents") through subsequent planned reviews and updates. The framework includes consolidation of existing guidelines and/or literature by expert reviewers, structured stages of public review, external field-testing, and ratification by COMP. This TQC development framework is a cross-country initiative that allows for rapid development of robust, community-driven living guideline documents that are owned by the community and reviewed to keep relevant in a rapidly evolving technical environment. Community engagement and uptake survey data shows 70% of Canadian centers are part of this process and that the data in the guideline documents reflect, and are influencing, the way Canadian radiation treatment centers run their technical quality control programs. For a medium-sized center comprising six linear accelerators and a comprehensive brachytherapy program, we evaluate the physics workload to 1.5 full-time equivalent physicists per year to complete all QC tests listed in this suite. PACS number(s): 87.55.Qr, 87.56.Fc, 87.56.-v. © 2016 The Authors.

  12. Production, review, and impact of technical quality control guidelines in a national context.

    PubMed

    Nielsen, Michelle K; Malkoske, Kyle E; Brown, Erika; Diamond, Kevin; Frenière, Normand; Grant, John; Pomerleau-Dalcourt, Natalie; Schella, Jason; Schreiner, L John; Tantôt, Laurent; Villareal-Barajas, J Eduardo; Bissonnette, Jean-Pierre

    2016-11-08

    A close partnership between the Canadian Partnership for Quality Radiotherapy (CPQR) and the Canadian Organization of Medical Physicist's (COMP) Quality Assurance and Radiation Safety Advisory Committee (QARSAC) has resulted in the development of a suite of Technical Quality Control (TQC) guidelines for radiation treatment equipment; they outline specific performance objectives and criteria that equipment should meet in order to assure an acceptable level of radiation treatment quality. The adopted framework for the development and maintenance of the TQCs ensures the guidelines incorporate input from the medical physics com-munity during development, measures the workload required to perform the QC tests outlined in each TQC, and remain relevant (i.e., "living documents") through subsequent planned reviews and updates. The framework includes consolidation of existing guidelines and/or literature by expert reviewers, structured stages of public review, external field-testing, and ratification by COMP. This TQC develop-ment framework is a cross-country initiative that allows for rapid development of robust, community-driven living guideline documents that are owned by the com-munity and reviewed to keep relevant in a rapidly evolving technical environment. Community engagement and uptake survey data shows 70% of Canadian centers are part of this process and that the data in the guideline documents reflect, and are influencing, the way Canadian radiation treatment centers run their technical quality control programs. For a medium-sized center comprising six linear accelerators and a comprehensive brachytherapy program, we evaluate the physics workload to 1.5 full-time equivalent physicists per year to complete all QC tests listed in this suite.

  13. Non-linear advanced control of the LHC inner triplet heat exchanger test unit

    NASA Astrophysics Data System (ADS)

    Viñuela, E. Blanco; Cubillos, J. Casas; de Prada Moraga, C.; Cristea, S.

    2002-05-01

    The future Large Hadron Collider (LHC) at CERN will include eight interaction region final focus magnet systems, the so-called "Inner Triplet," one on each side of the four beam collision points. The Inner Triplets will be cooled in a static bath of pressurized He II nominally at 1.9 K. This temperature is a control parameter and has very severe constraints in order to avoid the transition from the superconducting to normal resistive state. The main difference in these special zones with respect to a regular LHC cell is higher dynamic heat load unevenly distributed which modifies largely the process characteristics and hence the controller performance. Several control strategies have already been tested at CERN in a pilot plant (LHC String Test) which reproduced a LHC half-cell. In order to validate a common control structure along the whole LHC ring, a Nonlinear Model Predictive Control (NMPC) has been developed and implemented in the Inner Triplet Heat Exchanger Unit (IT-HXTU) at CERN. Automation of the Inner Triplet setup and the advanced control techniques deployed based on the Model Based Predictive Control (MBPC) principle are presented.

  14. Production of stable bispecific IgG1 by controlled Fab-arm exchange

    PubMed Central

    Gramer, Michael J; van den Bremer, Ewald TJ; van Kampen, Muriel D; Kundu, Amitava; Kopfmann, Peter; Etter, Eric; Stinehelfer, David; Long, Justin; Lannom, Tom; Noordergraaf, Esther H; Gerritsen, Jolanda; Labrijn, Aran F; Schuurman, Janine; van Berkel, Patrick HC; Parren, Paul WHI

    2013-01-01

    The manufacturing of bispecific antibodies can be challenging for a variety of reasons. For example, protein expression problems, stability issues, or the use of non-standard approaches for manufacturing can result in poor yield or poor facility fit. In this paper, we demonstrate the use of standard antibody platforms for large-scale manufacturing of bispecific IgG1 by controlled Fab-arm exchange. Two parental antibodies that each contain a single matched point mutation in the CH3 region were separately expressed in Chinese hamster ovary cells and manufactured at 1000 L scale using a platform fed-batch and purification process that was designed for standard antibody production. The bispecific antibody was generated by mixing the two parental molecules under controlled reducing conditions, resulting in efficient Fab-arm exchange of >95% at kg scale. The reductant was removed via diafiltration, resulting in spontaneous reoxidation of interchain disulfide bonds. Aside from the bispecific nature of the molecule, extensive characterization demonstrated that the IgG1 structural integrity was maintained, including function and stability. These results demonstrate the suitability of this bispecific IgG1 format for commercial-scale manufacturing using standard antibody manufacturing techniques. PMID:23995617

  15. Fault Diagnosis for the Heat Exchanger of the Aircraft Environmental Control System Based on the Strong Tracking Filter

    PubMed Central

    Ma, Jian; Lu, Chen; Liu, Hongmei

    2015-01-01

    The aircraft environmental control system (ECS) is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the system’s efficiency, which can lead to catastrophic consequences. Fault diagnosis of the heat exchanger is necessary to prevent risks. However, two problems hinder the implementation of the heat exchanger fault diagnosis in practice. First, the actual measured parameter of the heat exchanger cannot effectively reflect the fault occurrence, whereas the heat exchanger faults are usually depicted by utilizing the corresponding fault-related state parameters that cannot be measured directly. Second, both the traditional Extended Kalman Filter (EKF) and the EKF-based Double Model Filter have certain disadvantages, such as sensitivity to modeling errors and difficulties in selection of initialization values. To solve the aforementioned problems, this paper presents a fault-related parameter adaptive estimation method based on strong tracking filter (STF) and Modified Bayes classification algorithm for fault detection and failure mode classification of the heat exchanger, respectively. Heat exchanger fault simulation is conducted to generate fault data, through which the proposed methods are validated. The results demonstrate that the proposed methods are capable of providing accurate, stable, and rapid fault diagnosis of the heat exchanger. PMID:25823010

  16. Fault diagnosis for the heat exchanger of the aircraft environmental control system based on the strong tracking filter.

    PubMed

    Ma, Jian; Lu, Chen; Liu, Hongmei

    2015-01-01

    The aircraft environmental control system (ECS) is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the system's efficiency, which can lead to catastrophic consequences. Fault diagnosis of the heat exchanger is necessary to prevent risks. However, two problems hinder the implementation of the heat exchanger fault diagnosis in practice. First, the actual measured parameter of the heat exchanger cannot effectively reflect the fault occurrence, whereas the heat exchanger faults are usually depicted by utilizing the corresponding fault-related state parameters that cannot be measured directly. Second, both the traditional Extended Kalman Filter (EKF) and the EKF-based Double Model Filter have certain disadvantages, such as sensitivity to modeling errors and difficulties in selection of initialization values. To solve the aforementioned problems, this paper presents a fault-related parameter adaptive estimation method based on strong tracking filter (STF) and Modified Bayes classification algorithm for fault detection and failure mode classification of the heat exchanger, respectively. Heat exchanger fault simulation is conducted to generate fault data, through which the proposed methods are validated. The results demonstrate that the proposed methods are capable of providing accurate, stable, and rapid fault diagnosis of the heat exchanger.

  17. Interface-controlled layer exchange in metal-induced crystallization of germanium thin films

    NASA Astrophysics Data System (ADS)

    Hu, Shu; Marshall, Ann F.; McIntyre, Paul C.

    2010-08-01

    Low-temperature synthesis of polycrystalline germanium (poly-Ge) thin films is of great interest in thin-film photovoltaic and electronics applications. We demonstrate metal (Al)-induced crystallization to form poly-Ge thin films on both glass and polymer substrates at temperatures as low as 200 °C. An interfacial diffusion control layer, intentionally interposed between the Al and the underlying amorphous Ge (a-Ge) layer, is found to achieve layer exchange while suppressing uncontrolled Ge crystallization within the bilayer samples. Germanium thin films with micron-size grains and (111)-preferred orientation are prepared by controlled Ge nucleation and Ge lateral overgrowth of Al during a-Ge crystallization.

  18. Portable pilot plant for evaluating marine biofouling growth and control in heat exchangers-condensers.

    PubMed

    Casanueva, J F; Sánchez, J; García-Morales, J L; Casanueva-Robles, T; López, J A; Portela, J R; Nebot, E; Sales, D

    2003-01-01

    Biofouling frequently involves a serious impediment to achieving optimum operating conditions in heat exchangers-condensers. The economic coat and energy losses associated with this phenomenon are significant and the environmental impact of biocides must satisfy stringent regulations. A portable pilot plant has been designed in order to carry out in-situ experimental study as biofilm is formed under thermal and hydrodynamically controlled conditions. The pilot plant has an automatic monitoring, control and data acquisition system, which automatically processes data from indirect measure of fouling in terms of increased fluid frictional and heat transfer resistances. A particular method is used and proposed for direct measuring and biofilm characterization. Once we know the actual film thickness, we can calculate the effective thermal conductivity of the layer by using the appropriate heat transfer equations.

  19. Preliminary study of solar ponds for salinity control in the Colorado River Basin. Technical report

    SciTech Connect

    Boegli, W.J.; Dahl, M.M.; Remmers, H.E.

    1982-12-01

    In this study, the Bureau of Reclamation investigates the technical and economic benefits of using solar salt-gradient ponds in the Colorado River Basin to provide salinity control and to produce project power and freshwater. It was assumed that the saline water needed for pond construction would be transported to one of two dry lakebeds in the Basin(Danby Dry Lake in southern California or Sevier Dry Lake in western Utah) as part of a salinity control/coal transport project. The ponds would be used to generate electric power that could be integrated with the Bureau's power grid or used in combination with thermal energy from the ponds to power commercially available desalination systems to produce freshwater. Economic benefits were compiled for two methods of concentrating the necessary brine for the ponds--one representing stage construction using collected brine only and the other using salt at the site to produce the concentrated brine.

  20. The role of the OIE in information exchange and the control of animal diseases, including zoonoses.

    PubMed

    Poissonnier, C; Teissier, M

    2013-08-01

    The growing importance of animal diseases and zoonoses at a time when globalisation has increased movements of people, animals and animal products across the globe, has strengthened the role of the World Organisation for Animal Health (OIE) in animal disease control. The OIE's mandate since its establishment in 1924 has been to facilitate the exchange of public health, animal health and scientific information, and to further the control and eradication of animal diseases. The OIE is recognised by the World Trade Organization Agreement on the Application of Sanitary and Phytosanitary Measures as the international reference organisation for animal diseases and zoonoses, especially for standard setting. The standards adopted by the World Assembly of OIE Delegates on veterinary public health and animal health feature in the OlE Terrestrial Animal Health Code, the Aquatic Animal Health Code, the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals and the Manual of Diagnostic Tests for Aquatic Animals. The OlE is also a reference organisation for the exchange of public and animal health information among Member Countries, through an information, reporting and warning system based on transparent communication between countries. The OIE provides scientific expertise in ascertaining countries' status with regard to notifiable diseases, enabling them to secure official recognition as being free from foot and mouth disease, African horse sickness, contagious bovine pleuropneumonia and bovine spongiform encephalopathy. The OIE also contributes its scientific expertise to stakeholder training on the surveillance and control of animal diseases and zoonoses and to the evaluation of the performance of Veterinary Services, to enhance theirwork asthe cornerstone of their countries' disease control efforts.

  1. Supporting tobacco control: stimulating local newspaper coverage with a technical assistance website for local coalitions.

    PubMed

    Buller, David B; Bettinghaus, Erwin P; Helme, Donald; Young, Walter F; Borland, Ron; Maloy, Julie A; Cutter, Gary R; Andersen, Peter A; Walther, Joseph B

    2011-11-01

    A large and growing literature confirms that well-designed web-based programs can be effective in preventing or treating several chronic diseases. This study examined how the Internet can deliver information and train community activists and specifically tested the effects of web-based technical assistance on local tobacco control coalitions' efforts to use media advocacy to advance their agendas. The authors compared a highly interactive, Enhanced website (intervention) to a noninteractive, Basic text-based website (comparison) in Colorado communities. A total of 24 tobacco control coalitions led by local county health departments and nursing services were enrolled in the project and randomly assigned to use either the intervention or comparison website. A total of 73 local daily and weekly newspapers were identified in the service areas of 23 of the 24 coalitions. A posttest assessment of newspaper coverage was conducted to locate all newspaper articles with tobacco control information published between January 1 and April 9, 2004, the last 3 months of the intervention. Although there was no evidence of a treatment effect on the frequency of newspaper articles on tobacco-related issues, there was, however, evidence that newspapers in counties where the coalition had access to the Enhanced website printed more stories focused on local/regional issues and more anti-tobacco local/regional stories than in the counties where coalitions had access to the Basic website. Coalitions can improve their influence on local media for community tobacco control when high-quality online technical assistance, training, and resources are available to them.

  2. Cecal intubation time between cap-assisted water exchange and water exchange colonoscopy: a randomized-controlled trial.

    PubMed

    Tseng, Chih-Wei; Koo, Malcolm; Hsieh, Yu-Hsi

    2017-11-01

    The water exchange (WE) method can decrease the discomfort of the patients undergoing colonoscopy. It also provides salvage cleansing and improves adenoma detection, but a longer intubation time is required. Cap-assisted colonoscopy leads to a significant reduction in cecal intubation time compared with traditional colonoscopy with air insufflation. The aim of this study was to investigate whether combined cap-assisted colonoscopy and water exchange (CWE) could decrease the cecal intubation time compared with WE. A total of 120 patients undergoing fully sedated colonoscopy at a regional hospital in southern Taiwan were randomized to colonoscopy with either CWE (n=59) or WE (n=61). The primary endpoint was cecal intubation time. The mean cecal intubation time was significantly shorter in CWE (12.0 min) compared with WE (14.8 min) (P=0.004). The volume of infused water during insertion was lower in CWE (840 ml) compared with WE (1044 ml) (P=0.003). The adenoma detection rate was 50.8 and 47.5% for CWE and WE, respectively (P=0.472). The Boston Bowel Preparation Scale scores were comparable in the two groups. Results from the multiple linear regression analysis indicated that WE with a cap, a higher degree of endoscopist's experience, a higher Boston Bowel Preparation Scale score, and a lower volume of water infused during insertion, without abdominal compression, without change of position, and without chronic laxative use, were significantly associated with a shorter cecal intubation time. In comparison with WE, CWE could shorten the cecal intubation time and required lower volume of water infusion during insertion without compromising the cleansing effect of WE.

  3. Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation

    SciTech Connect

    B. E. Law; E. Falgeb; L. Guc; D. D. Baldocchic; P. Bakwind; P. Berbigiere; K. Davisf; A. J. Dolmang; M. Falkh; J. D. Fuentesi; A. Goldsteinc; A. Granierj; A. Grellek; D. Hollingerl; I. A. Janssensm; P. Jarvisn; N. O. Jenseno; G. Katulp; Y. Mahliq; G. Matteuccir; T. Meyerss; R. Monsont; W. Mungeru; W. Oechelv; R. Olsonw; K. Pilegaardx; K. T. Paw Uh; H. Thorgeirssony; R. Valentinir; S. Vermaz; T. Vesalaa1; K. Wilsons; S. Wofsyu

    2002-12-02

    The objective of this research was to compare seasonal and annual estimates of CO2 and water vapor exchange across sites in forests, grasslands, crops, and tundra that are part of an international network called FLUXNET, and to investigating the responses of vegetation to environmental variables. FLUXNETs goals are to understand the mechanisms controlling the exchanges of CO2, water vapor and energy across a spectrum of time and space scales, and to provide information for modeling of carbon and water cycling across regions and the globe. At a subset of sites, net carbon uptake (net ecosystem exchange, the net of photosynthesis and respiration) was greater under diffuse than under direct radiation conditions, perhaps because of a more efficient distribution of non-saturating light conditions for photosynthesis, lower vapor pressure deficit limitation to photosynthesis, and lower respiration associated with reduced temperature. The slope of the relation between monthly gross ecosystem production and evapotranspiration was similar between biomes, except for tundra vegetation, showing a strong linkage between carbon gain and water loss integrated over the year (slopes=3.4 g CO2/kg H2O for grasslands, 3.2 for deciduous broadleaf forests, 3.1 for crops, 2.4 for evergreen conifers, and 1.5 for tundra vegetation). The ratio of annual ecosystem respiration to gross photosynthesis averaged 0.83, with lower values for grasslands, presumably because of less investment in respiring plant tissue compared with forests. Ecosystem respiration was weakly correlated with mean annual temperature across biomes, in spite of within site sensitivity over shorter temporal scales. Mean annual temperature and site water balance explained much of the variation in gross photosynthesis. Water availability limits leaf area index over the long-term, and inter-annual climate variability can limit carbon uptake below the potential of the leaf area present.

  4. NNARX model structure for the purposes of controller design and optimization of heat exchanger process control training system operation

    NASA Astrophysics Data System (ADS)

    Mulyana, Tatang

    2017-04-01

    This paper presents a performance of Neural Network Autoregressive with Exogenous Input (NNARX) model structure and evaluates the training data that provides robust model on fresh data set, using neural network type of back-propagation known as multilayer perceptron (MPP). The plant under test is a heat exchanger process control training system called QAD Model BDT 921. A real input-output data has been collected and will be used to identify the plant. The model was estimated by prediction error method with Levenberg-Marquardt algorithm for training neural networks. It is expected that the training data covering the full operating condition will be the optimum training data. The model was validated by residual analysis and model fit. It will be presented and concluded. The simulation results show that the identification is able to identify plant's good model. This identification can be used to design the plant controller and improve its performance.

  5. Sodium/Proton exchanger 3 in the medulla oblongata and set point of breathing control.

    PubMed

    Wiemann, Martin; Frede, Stilla; Bingmann, Dieter; Kiwull, Peter; Kiwull-Schöne, Heidrun

    2005-07-15

    In vivo inhibition of the sodium/proton exchanger 3 (NHE3) in chemosensitive neurons of the ventrolateral brainstem augments central respiratory drive in anesthetized rabbits. To further explore the possible role of this exchanger for the control of breathing, we examined the individual relationship between brainstem NHE3 abundance and ventilation in rabbits during wakefulness. In 32 adult male rabbits on standard nutritional alkali load, alveolar ventilation, metabolic CO2 production, and blood gases were determined, together with arterial and urinary acid-base status and renal base control functions. Expression of NHE3 in brainstem tissue from the obex region was determined by quantitative real-time reverse-transcription polymerase chain reaction analysis. Regarding the distribution above and below the median, we classified high and low brainstem NHE3 animals, expressing a mean (+/- SEM) NHE3 mRNA of 2.08 +/- 0.28 and 0.72 +/- 0.06 fg cDNA/mg RNA, respectively. Alveolar ventilation of high brainstem NHE3 animals was lower than that of low brainstem NHE3 animals (715 +/- 36 vs. 919 +/- 41 ml . minute(-1); p < 0.01), a finding also reflected by a marked difference in Pa(CO2) (5.24 +/- 0.16 vs. 4.44 +/- 0.15 kPa; p < 0.01). Among possible secondary factors, CO2 production, systemic base excess, and fractional renal base reabsorption were not found to be different. We conclude that the level of brainstem NHE3 expression-most likely via intracellular pH modulation-contributes to the individual control of breathing and Pa(CO2) in conscious rabbits by adjusting the set point and the loop gain of the system.

  6. Solvent exchange module for LC-NMR hyphenation using machine vision-controlled droplet evaporation.

    PubMed

    Schoonen, Jan-Willem; Vulto, Paul; de Roo, Niels; van Duynhoven, John; van der Linden, Heiko; Hankemeier, Thomas

    2013-06-18

    We report the use of pendant droplet evaporation for exchange of eluents for (1)H nuclear magnetic resonance ((1)H NMR) purposes. Analytes are fed and retained in 500 nL droplets, which are concentrated by evaporation and subsequently redissolved in deuterated solvent. Droplet size is monitored by machine vision (MV), and heating rates are adjusted concordingly to maintain a stable droplet volume. Evaporation control is independent of solvent properties, and the setup handles feed rates up to 7 μL min(-1). The interface is capable of exchanging up to 90% of solvent for deuterated solvent, with a good recovery and repeatability for tomato extracts (Solanum lycopersicum). The system was capable of handling both polar and nonpolar analytes in one run. Volatiles such as formate, acetate, and lactate and the thermosensitive compound epigallocatechin gallate were recovered without significant losses. Ethanol and propionate were recovered with significant losses due to the formation of a minimum boiling azeotrope. The current setup is ideally suited for on- and off-line hyphenation of liquid chromatography and NMR, as it is comprehensive, fully automated, and easy to operate.

  7. An efficient process of generating bispecific antibodies via controlled Fab-arm exchange using culture supernatants.

    PubMed

    Paul, Suparna; Connor, Judy; Nesspor, Tom; Haytko, Peter; Boakye, Ken; Chiu, Mark L; Jiang, Haiyan

    2016-05-01

    Bispecific antibody generation is actively pursued for therapeutic and research antibody development. Although there are multiple strategies for generating bispecific antibodies (bsAbs); the common challenge is to develop a scalable method to prepare bsAbs with high purity and yield. The controlled Fab-arm exchange (cFAE) method combines two parental monoclonal antibodies (mAbs), each with a matched point mutation, F405L and K409R in the respective CH3 domains. The conventional process employs two steps: the purification of two parental mAbs from culture supernatants followed by cFAE. Following a reduction/oxidation reaction, the bispecific mAb is formed with greater than 95% heterodimerization efficiency. In this study, cFAE was initiated in culture supernatants expressing the two parental mAbs, thereby eliminating the need to first purify the parental mAbs. The bsAbs formed in culture supernatant was then purified using a Protein A affinity chromatography. The BsAbs generated in this manner had efficiency comparable to the conventional method using purified parental mAbs. BsAbs prepared by two different routes showed indistinguishable characteristics by SDS capillary electrophoresis, analytical size exclusion, and cation exchange chromatography. This alternative method significantly shortened timelines and reduced resources required for bsAb generation, providing an improved process with potential benefits in large-scale bsAb preparation, as well as for HTP small-scale bsAb matrix selection.

  8. Reach-scale cation exchange controls on major ion chemistry of an Antarctic glacial meltwater stream

    USGS Publications Warehouse

    Gooseff, Michael N.; McKnight, Diane M.; Runkel, Robert L.

    2004-01-01

    McMurdo dry valleys of Antarctica represent the largest of the ice-free areas on the Antarctic continent, containing glaciers, meltwater streams, and closed basin lakes. Previous geochemical studies of dry valley streams and lakes have addressed chemical weathering reactions of hyporheic substrate and geochemical evolution of dry valley surface waters. We examine cation transport and exchange reactions during a stream tracer experiment in a dry valley glacial meltwater stream. The injection solution was composed of dissolved Li+, Na+, K+, and Cl-. Chloride behaved conservatively in this stream, but Li+, Na+, and K+ were reactive to varying degrees. Mass balance analysis indicates that relative to Cl-, Li+ and K+ were taken up in downstream transport and Na+ was released. Simulations of conservative and reactive (first-order uptake or generation) solute transport were made with the OTIS (one-dimensional solute transport with inflow and storage) model. Among the four experimental reaches of Green Creek, solute transport simulations reveal that Li+ was removed from stream water in all four reaches, K+ was released in two reaches, taken up in one reach, and Na+ was released in all four reaches. Hyporheic sediments appear to be variable with uptake of Li+ in two reaches, uptake of K+ in one reach, release of K+ in two reaches, and uptake of Na+ in one reach. Mass balances of the conservative and reactive simulations show that from 1.05 to 2.19 moles of Li+ was adsorbed per reach, but less than 0.3 moles of K+ and less than 0.9 moles of Na+ were released per reach. This suggests that either (1) exchange of another ion which was not analyzed in this experiment or (2) that both ion exchange and sorption control inorganic solute transport. The elevated cation concentrations introduced during the experiment are typical of initial flows in each flow season, which flush accumulated dry salts from the streambed. We propose that the bed sediments (which compose the hyporheic

  9. Environmental Controls and Management Effects on Ecosystem Carbon Exchange in Two Grazed Temperate Grasslands

    NASA Astrophysics Data System (ADS)

    Ni Choncubhair, O.; Humphreys, J.; Lanigan, G.

    2013-12-01

    Temperate grasslands constitute over 30% of the Earth's naturally-occurring biomes and make an important contribution towards the partial mitigation of anthropogenic greenhouse gas emissions by terrestrial ecosystems. Accumulation of carbon (C) in grassland systems predominantly takes place in below-ground repositories, enhanced by the presence of a stable soil environment with low carbon turnover rates, active rhizodeposition and high levels of residue and organic inputs. However, this C sequestration is strongly influenced by soil characteristics and climatic variables. Furthermore, in managed pasture systems, carbon exchange across the soil-atmosphere boundary is additionally affected by management activities, such as biomass removal, grazing events and the deposition or application of organic amendments. These biotic and abiotic factors contribute greatly towards the large uncertainty associated with the carbon balance of grassland ecosystems and demand further analysis. In the present study, the controls and drivers of carbon dynamics in two rotationally-grazed grasslands in Ireland were examined. The sites experience similar temperate climatic regimes but differ in soil texture classification and stocking rate. Eddy covariance measurements of net ecosystem exchange of carbon were complemented by regular assessment of standing biomass, leaf cover, harvest exports and organic amendment inputs. Our study showed that mild weather conditions and an extended growing season sustained net C accumulation at both sites for at least ten months of the year. Despite differing soil drainage characteristics, winter fluxes of net carbon exchange and its component fluxes, gross photosynthesis and ecosystem respiration, were highly comparable between the two sites. Management practices during the active growing season exerted a strong influence on both the direction and the rate of C exchange in the grassland systems, with a strong dependence, however, on the timing and

  10. Surfactant control of air-sea gas exchange across contrasting biogeochemical regimes

    NASA Astrophysics Data System (ADS)

    Pereira, Ryan; Schneider-Zapp, Klaus; Upstill-Goddard, Robert

    2014-05-01

    Air-sea gas exchange is important to the global partitioning of CO2.Exchange fluxes are products of an air-sea gas concentration difference, ΔC, and a gas transfer velocity, kw. The latter is controlled by the rate of turbulent diffusion at the air-sea interface but it cannot be directly measured and has a high uncertainty that is now considered one of the greatest challenges to quantifying net global air-sea CO2 exchange ...(Takahashi et al., 2009). One important control on kw is exerted by sea surface surfactants that arise both naturally from biological processes and through anthropogenic activity. They influence gas exchange in two fundamental ways: as a monolayer physical barrier and through modifying sea surface hydrodynamics and hence turbulent energy transfer. These effects have been demonstrated in the laboratory with artificial surfactants ...(Bock et al., 1999; Goldman et al., 1988) and through purposeful surfactant releases in coastal waters .(.).........().(Brockmann et al., 1982) and in the open ocean (Salter et al., 2011). Suppression of kwin these field experiments was ~5-55%. While changes in both total surfactant concentration and the composition of the natural surfactant pool might be expected to impact kw, the required in-situ studies are lacking. New data collected from the coastal North Sea in 2012-2013 shows significant spatio-temporal variability in the surfactant activity of organic matter within the sea surface microlayer that ranges from 0.07-0.94 mg/L T-X-100 (AC voltammetry). The surfactant activities show a strong winter/summer seasonal bias and general decrease in concentration with increasing distance from the coastline possibly associated with changing terrestrial vs. phytoplankton sources. Gas exchange experiments of this seawater using a novel laboratory tank and gas tracers (CH4 and SF6) demonstrate a 12-45% reduction in kw compared to surfactant-free water. Seasonally there is higher gas exchange suppression in the summer

  11. Development, Technical, and User Evaluation of a Web Mobile Application for Self-Control of Diabetes.

    PubMed

    Garcia-Zapirain, Begoña; de la Torre Díez, Isabel; Sainz de Abajo, Beatriz; López-Coronado, Miguel

    2016-09-01

    The main objective of this research was to develop and evaluate a Web-based mobile application (app) known as "Diario Diabetes" on both a technical and user level, by means of which individuals with diabetes may monitor their illness easily at any time and in any place using any device that has Internet access. The technologies used to develop the app were HTML, CSS, JavaScript, PHP, and MySQL, all of which are an open source. Once the app was developed, it was evaluated on a technical level (by measuring loading times) and on a user level, through a survey. Different loading times for the application were measured, with it being noted that under no circumstances does this exceed 2 s. Usability was evaluated by 150 users who initially used the application. A majority (71%) of users used a PC to access the app, 83% considered the app's design to be attractive, 67% considered the tasks to be very useful, and 67% found it very easy to use. Although applications exist for controlling diabetes both at mobile virtual shops or on a research level, our app may help to improve the administration of these types of patients and they are the ones who will ultimately opt for one or the other. According to the results obtained, we can state that all users would recommend the app's use to other users.

  12. Locus of control, sources of motivation, and mental boundaries as antecedents of leader-member exchange quality.

    PubMed

    Barbuto, John E; Finch, Weltmer Dayna; Pennisi, Lisa A

    2010-02-01

    In this study were examined leaders' and members' scores on locus of control, sources of motivation, and mental boundaries to predict the quality of leader-member exchanges. 80 elected officials and their 388 direct reports were sampled in a field study. Analysis indicated followers' scores on locus of control, leaders' scores of self-concept internal motivation, leaders' scores on locus of control, and followers' rated goal-internalization motivation were positively related to leader-member exchanges. Implications and directions for research are discussed.

  13. BARTER: Behavior Profile Exchange for Behavior-Based Admission and Access Control in MANETs

    NASA Astrophysics Data System (ADS)

    Frias-Martinez, Vanessa; Stolfo, Salvatore J.; Keromytis, Angelos D.

    Mobile Ad-hoc Networks (MANETs) are very dynamic networks with devices continuously entering and leaving the group. The highly dynamic nature of MANETs renders the manual creation and update of policies associated with the initial incorporation of devices to the MANET (admission control) as well as with anomaly detection during communications among members (access control) a very difficult task. In this paper, we present BARTER, a mechanism that automatically creates and updates admission and access control policies for MANETs based on behavior profiles. BARTER is an adaptation for fully distributed environments of our previously introduced BB-NAC mechanism for NAC technologies. Rather than relying on a centralized NAC enforcer, MANET members initially exchange their behavior profiles and compute individual local definitions of normal network behavior. During admission or access control, each member issues an individual decision based on its definition of normalcy. Individual decisions are then aggregated via a threshold cryptographic infrastructure that requires an agreement among a fixed amount of MANET members to change the status of the network. We present experimental results using content and volumetric behavior profiles computed from the ENRON dataset. In particular, we show that the mechanism achieves true rejection rates of 95% with false rejection rates of 9%.

  14. A review of fault tolerant control strategies applied to proton exchange membrane fuel cell systems

    NASA Astrophysics Data System (ADS)

    Dijoux, Etienne; Steiner, Nadia Yousfi; Benne, Michel; Péra, Marie-Cécile; Pérez, Brigitte Grondin

    2017-08-01

    Fuel cells are powerful systems for power generation. They have a good efficiency and do not generate greenhouse gases. This technology involves a lot of scientific fields, which leads to the appearance of strongly inter-dependent parameters. This makes the system particularly hard to control and increases fault's occurrence frequency. These two issues call for the necessity to maintain the system performance at the expected level, even in faulty operating conditions. It is called ;fault tolerant control; (FTC). The present paper aims to give the state of the art of FTC applied to the proton exchange membrane fuel cell (PEMFC). The FTC approach is composed of two parts. First, a diagnosis part allows the identification and the isolation of a fault; it requires a good a priori knowledge of all the possible faults. Then, a control part allows an optimal control strategy to find the best operating point to recover/mitigate the fault; it requires the knowledge of the degradation phenomena and their mitigation strategies.

  15. Improving dynamic performance of proton-exchange membrane fuel cell system using time delay control

    NASA Astrophysics Data System (ADS)

    Kim, Young-Bae

    Transient behaviour is a key parameter for the vehicular application of proton-exchange membrane (PEM) fuel cell. The goal of this presentation is to construct better control technology to increase the dynamic performance of a PEM fuel cell. The PEM fuel cell model comprises a compressor, an injection pump, a humidifier, a cooler, inlet and outlet manifolds, and a membrane-electrode assembly. The model includes the dynamic states of current, voltage, relative humidity, stoichiometry of air and hydrogen, cathode and anode pressures, cathode and anode mass flow rates, and power. Anode recirculation is also included with the injection pump, as well as anode purging, for preventing anode flooding. A steady-state, isothermal analytical fuel cell model is constructed to analyze the mass transfer and water transportation in the membrane. In order to prevent the starvation of air and flooding in a PEM fuel cell, time delay control is suggested to regulate the optimum stoichiometry of oxygen and hydrogen, even when there are dynamical fluctuations of the required PEM fuel cell power. To prove the dynamical performance improvement of the present method, feed-forward control and Linear Quadratic Gaussian (LQG) control with a state estimator are compared. Matlab/Simulink simulation is performed to validate the proposed methodology to increase the dynamic performance of a PEM fuel cell system.

  16. Controlled methyl-esterification of pectin catalyzed by cation exchange resin.

    PubMed

    Peng, Xiaoxia; Yang, Guang; Fan, Xingchen; Bai, Yeming; Ren, Xiaomeng; Zhou, Yifa

    2016-02-10

    This study developed a new method to methyl-esterify pectin using a cation exchange resin. Homogalacturonan (HG)-type pectin (WGPA-3-HG) and rhamnogalacturonan (RG)-I-type pectin (AHP-RG) obtained from the roots of Panax ginseng and sunflower heads, respectively, were used as models. Compared to commonly used methyl-esterification methods that use either methyl iodide or acidified methanol, the developed method can methyl-esterify both HG- and RG-I-type pectins without degrading their structures via β-elimination or acid hydrolysis. In addition, by modifying reaction conditions, including the mass ratio of resin to pectin, reaction time, and temperature, the degree of esterification can be controlled. Moreover, the resin and methanol can be recycled to conserve resources, lower costs, and reduce environmental pollution. This new methodology will be highly useful for industrial esterification of pectin.

  17. Integration and exchange of split dCas9 domains for transcriptional controls in mammalian cells

    PubMed Central

    Ma, Dacheng; Peng, Shuguang; Xie, Zhen

    2016-01-01

    Programmable and precise regulation of dCas9 functions in response to multiple molecular signals by using synthetic gene circuits will expand the application of the CRISPR-Cas technology. However, the application of CRISPR-Cas therapeutic circuits is still challenging due to the restrictive cargo size of existing viral delivery vehicles. Here, we construct logic AND circuits by integrating multiple split dCas9 domains, which is useful to reduce the size of synthetic circuits. In addition, we engineer sensory switches by exchanging split dCas9 domains, allowing differential regulations on one gene, or activating two different genes in response to cell-type specific microRNAs. Therefore, we provide a valuable split-dCas9 toolkit to engineer complex transcription controls, which may inspire new biomedical applications. PMID:27694915

  18. Advanced emissions control development program. Quarterly technical progress report No. 9, October 1--December 31, 1996

    SciTech Connect

    Evans, A.P.

    1996-12-31

    Babcock & Wilcox (B&W) is conducting a five-year project aimed at the development of practical, cost-effective strategies for reducing the emissions of hazardous air pollutants (commonly called air toxics) from coal-fired electric utility plants. The need for air toxic emissions controls may arise as the U.S. Environmental Protection Agency proceeds with implementation of Title III of the Clean Air Act Amendment of 1990. Data generated during the program will provide utilities with the technical and economic information necessary to reliably evaluate various air toxics emission compliance options such as fuel switching, coal cleaning, and flue gas treatment. The development work is being carried out using B&W`s new Clean Environment Development Facility (CEDF) wherein air toxics emission control strategies can be developed under controlled conditions, and with proven predictability to commercial systems. Tests conducted in the CEDF provide high quality, repeatable, comparable data over a wide range of coal properties, operating conditions, and emissions control systems. Development work to date has concentrated on the capture of mercury, other trace metals, fine particulate, and the inorganic species hydrogen chloride and hydrogen fluoride.

  19. Controlled cervical extension osteotomy for ankylosing spondylitis utilizing the Jackson operating table: technical note.

    PubMed

    Chin, Kingsley R; Ahn, Jaimo

    2007-08-01

    Technical note. To demonstrate a controlled extension osteotomy technique of the cervical spine in a prone position and using the head elevator mechanism on the Jackson operating table to correct a chin-on-chest deformity in a patient with ankylosing spondylitis. Catastrophic cord injury causing quadriplegia and death has been associated with correction of chin-on-chest deformity in patients with ankylosing spondylitis. Manual control of spinal column motion during and after osteoclasis or osteotomy can be difficult, inexact, and anxiety inducing. A 45-year-old woman with ankylosing spondylitis and severe chin-on-chest deformity underwent a posterior C7 pedicle subtraction osteotomy, deformity correction, and instrumented fusion in a prone position on the Jackson operating table. By using the elevator mechanism attached to the head of the operating table and Mayfield tongs, the patient's cervicothoracic junction was placed into extension by over 30 degrees in controlled increments. We present a technique for controlled extension osteotomy correction of chin-on-chest deformity in a prone position. Use of the operating table mechanism in conjunction with a closing-wedge osteotomy diminishes the risk of translation, decreases risk of air embolus associated with a sitting position, and promotes greater opportunity for fusion through the osteotomy, and the stability allows for placement of modern instrumentation.

  20. Perfluorocarbon-associated gas exchange (partial liquid ventilation) in respiratory distress syndrome: a prospective, randomized, controlled study.

    PubMed

    Leach, C L; Fuhrman, B P; Morin, F C; Rath, M G

    1993-09-01

    To determine the efficacy of perfluorocarbon-associated gas exchange (partial liquid ventilation) in respiratory distress syndrome. Prospective, randomized, controlled study. State University of New York at Buffalo, School of Medicine and Biomedical Sciences. Eleven premature lambs with respiratory distress syndrome, delivered by cesarean section. Five lambs were supported by conventional mechanical ventilation alone. Six lambs were switched to perfluorocarbon-associated gas exchange after 60 to 90 mins of conventional mechanical ventilation. Perfluorocarbon-associated gas exchange was accomplished by instilling a volume of liquid perfluorocarbon equivalent to normal functional residual capacity (30 mL/kg) into the trachea, performing 3 to 4 mins of tidal liquid ventilation, and, at end-expiration, with liquid functional residual capacity of 30 mL/kg remaining in the lung, reconnecting the animal to the volume ventilator for gas tidal volumes. Serial arterial blood gases and lung mechanics were measured. While receiving conventional ventilation, all animals developed progressive hypoxemia, hypercarbia, and acidosis. However, in the perfluorocarbon-associated gas exchange group, within 5 mins of the initiation of perfluorocarbon-associated gas exchange, mean PaO2 increased four-fold, from 59 +/- 6 torr (7.9 +/- 0.8 kPa) during conventional ventilation to 250 +/- 28 torr (33.3 +/- 3.7 kPa; p < .05) during perfluorocarbon-associated gas exchange, and this increase was sustained at 60 mins of perfluorocarbon-associated gas exchange (268 +/- 38 torr; 35.7 +/- 5.1 kPa; p < .05). Mean PaCO2 decreased progressively from 62 +/- 4 torr (8.3 +/- 0.5 kPa) during conventional ventilation to 38 +/- 3.3 torr (5.1 +/- 0.4 kPa) at 60 mins of perfluorocarbon-associated gas exchange (p < .05). Mean pH concomitantly increased. Dynamic compliance increased three-fold within 15 mins of instituting perfluorocarbon-associated gas exchange, from 0.31 +/- 0.02 mL/cm H2O during conventional

  1. Biotic, abiotic, and management controls on methanol exchange above a temperate mountain grassland

    NASA Astrophysics Data System (ADS)

    HöRtnagl, Lukas; Bamberger, Ines; Graus, Martin; Ruuskanen, Taina M.; Schnitzhofer, Ralf; Müller, Markus; Hansel, Armin; Wohlfahrt, Georg

    2011-09-01

    Methanol (CH3OH) fluxes were quantified above a managed temperate mountain grassland in the Stubai Valley (Tyrol, Austria) during the growing seasons 2008 and 2009. Half-hourly methanol fluxes were calculated by means of the virtual disjunct eddy covariance (vDEC) method using three-dimensional wind data from a sonic anemometer and methanol volume mixing ratios measured with a proton transfer reaction mass spectrometer (PTR-MS). During (undisturbed) mature and growing phases, methanol fluxes exhibited a clear diurnal cycle with close-to-zero fluxes during nighttime and emissions, up to 10 nmol m-2 s-1, which followed the diurnal course of radiation and air temperature. Management events were found to represent the largest perturbations of methanol exchange at the studied grassland ecosystem: Peak emissions of 144.5 nmol m-2 s-1 were found during/after cutting of the meadow, reflecting the wounding of the plant material and subsequent depletion of the leaf internal aqueous methanol pools. After the application of organic fertilizer, elevated methanol emissions of up to 26.7 nmol m-2 s-1 were observed, likely reflecting enhanced microbial activity associated with the applied manure. Simple and multiple linear regression analyses revealed air temperature and radiation as the dominant abiotic controls, jointly explaining 47% and 70% of the variability in half-hourly and daily methanol fluxes. In contrast to published leaf-level laboratory studies, the surface conductance and the daily change in the amount of green plant area, used as ecosystem-scale proxies for stomatal conductance and growth, respectively, were found to exert only minor biotic controls on methanol exchange.

  2. Biotic, abiotic and management controls on methanol exchange above a temperate mountain grassland

    PubMed Central

    Hörtnagl, Lukas; Bamberger, Ines; Graus, Martin; Ruuskanen, Taina M.; Schnitzhofer, Ralf; Müller, Markus; Hansel, Armin; Wohlfahrt, Georg

    2013-01-01

    Methanol (CH3OH) fluxes were quantified above a managed temperate mountain grassland in the Stubai Valley (Tyrol, Austria) during the growing seasons 2008 and 2009. Half-hourly methanol fluxes were calculated by means of the virtual disjunct eddy covariance (vDEC) method using 3-dimensional wind data from a sonic anemometer and methanol volume mixing ratios measured with a proton-transfer-reaction mass spectrometer (PTR-MS). During (undisturbed) mature and growing phases methanol fluxes exhibited a clear diurnal cycle with close-to-zero fluxes during nighttime and emissions, up to 10 nmol m−2 s−1, which followed the diurnal course of radiation and air temperature. Management events were found to represent the largest perturbations of methanol exchange at the studied grassland ecosystem: Peak emissions of 144.5 nmol m−2 s−1 were found during/after cutting of the meadow reflecting the wounding of the plant material and subsequent depletion of the leaf internal aqueous methanol pools. After the application of organic fertilizer, elevated methanol emissions of up to 26.7 nmol m−2 s−1 were observed, likely reflecting enhanced microbial activity associated with the applied manure. Simple and multiple linear regression analyses revealed air temperature and radiation as the dominant abiotic controls, jointly explaining 47 % and 70 % of the variability in half-hourly and daily methanol fluxes. In contrast to published leaf-level laboratory studies, the surface conductance and the daily change in the amount of green plant area, used as ecosystem-scale proxies for stomatal conductance and growth, respectively, were found to exert only minor biotic controls on methanol exchange. PMID:24349901

  3. Tantalum acetabular augments in one-stage exchange of infected total hip arthroplasty: a case-control study.

    PubMed

    Klatte, Till Orla; Kendoff, Daniel; Sabihi, Reza; Kamath, Atul F; Rueger, Johannes M; Gehrke, Thorsten

    2014-07-01

    During the one-stage exchange procedure for periprosthetic joint infection (PJI) after total hip arthroplasty (THA), acetabular defects challenge reconstructive options. Porous tantalum augments are an established tool for addressing acetabular destruction in aseptic cases, but their utility in septic exchange is unknown. This retrospective case-control study presents the initial results of tantalum augmentation during one-stage exchange for PJI. Primary endpoints were rates of re-infection and short-term complications associated with this technique. Study patients had no higher risk of re-infection with equivalent durability at early follow-up with a re-infection rate in both groups of 4%. In conclusion, tantalum augments are a viable option for addressing acetabular defects in one-stage exchange for septic THA. Further study is necessary to assess long-term durability when compared to traditional techniques for acetabular reconstruction. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Characterization and control of the microbial community affiliated with copper or aluminum heat exchangers of HVAC systems.

    PubMed

    Schmidt, Michael G; Attaway, Hubert H; Terzieva, Silva; Marshall, Anna; Steed, Lisa L; Salzberg, Deborah; Hamoodi, Hameed A; Khan, Jamil A; Feigley, Charles E; Michels, Harold T

    2012-08-01

    Microbial growth in heating ventilation and air-conditioning (HVAC) systems with the subsequent contamination of indoor air is of increasing concern. Microbes and the subsequent biofilms grow easily within heat exchangers. A comparative study where heat exchangers fabricated from antimicrobial copper were evaluated for their ability to limit microbial growth was conducted using a full-scale HVAC system under conditions of normal flow rates using single-pass outside air. Resident bacterial and fungal populations were quantitatively assessed by removing triplicate sets of coupons from each exchanger commencing the fourth week after their installation for the next 30 weeks. The intrinsic biofilm associated with each coupon was extracted and characterized using selective and differential media. The predominant organisms isolated from aluminum exchangers were species of Methylobacterium of which at least three colony morphologies and 11 distinct PFGE patterns we found; of the few bacteria isolated from the copper exchangers, the majority were species of Bacillus. The concentrations and type of bacteria recovered from the control, aluminum, exchangers were found to be dependent on the type of plating media used and were 11,411-47,257 CFU cm(-2) per coupon surface. The concentration of fungi was found to average 378 CFU cm(-2). Significantly lower concentrations of bacteria, 3 CFU cm(-2), and fungi, 1 CFU cm(-2), were recovered from copper exchangers regardless of the plating media used. Commonly used aluminum heat exchangers developed stable, mixed, bacterial/fungal biofilms in excess of 47,000 organisms per cm(2) within 4 weeks of operation, whereas the antimicrobial properties of metallic copper were able to limit the microbial load affiliated with the copper heat exchangers to levels 99.97 % lower during the same time period.

  5. The design and implementation of the Technical Facilities Controller (TFC) for the Goldstone deep space communications complex

    NASA Technical Reports Server (NTRS)

    Killian, D. A.; Menninger, F. J.; Gorman, T.; Glenn, P.

    1988-01-01

    The Technical Facilities Controller is a microprocessor-based energy management system that is to be implemented in the Deep Space Network facilities. This system is used in conjunction with facilities equipment at each of the complexes in the operation and maintenance of air-conditioning equipment, power generation equipment, power distribution equipment, and other primary facilities equipment. The implementation of the Technical Facilities Controller was completed at the Goldstone Deep Space Communications Complex and is now operational. The installation completed at the Goldstone Complex is described and the utilization of the Technical Facilities Controller is evaluated. The findings will be used in the decision to implement a similar system at the overseas complexes at Canberra, Australia, and Madrid, Spain.

  6. Low power proton exchange membrane fuel cell system identification and adaptive control

    NASA Astrophysics Data System (ADS)

    Yang, Yee-Pien; Wang, Fu-Cheng; Chang, Hsin-Ping; Ma, Ying-Wei; Weng, Biing-Jyh

    This paper proposes a systematic method of system identification and control of a proton exchange membrane (PEM) fuel cell. This fuel cell can be used for low-power communication devices involving complex electrochemical reactions of nonlinear and time-varying dynamic properties. From a system point of view, the dynamic model of PEM fuel cell is reduced to a configuration of two inputs, hydrogen and air flow rates, and two outputs, cell voltage and current. The corresponding transfer functions describe linearized subsystem dynamics with finite orders and time-varying parameters, which are expressed as discrete-time auto-regression moving-average with auxiliary input models for system identification by the recursive least square algorithm. In the experiments, a pseudo-random binary sequence of hydrogen or air flow rate is fed to a single fuel cell device to excite its dynamics. By measuring the corresponding output signals, each subsystem transfer function of reduced order is identified, while the unmodeled, higher-order dynamics and disturbances are described by the auxiliary input term. This provides a basis of adaptive control strategy to improve the fuel cell performance in terms of efficiency, as well as transient and steady state specifications. Simulation shows that adaptive controller is robust to the variation of fuel cell system dynamics, and it has proved promising from the experimental results.

  7. qcML: an exchange format for quality control metrics from mass spectrometry experiments.

    PubMed

    Walzer, Mathias; Pernas, Lucia Espona; Nasso, Sara; Bittremieux, Wout; Nahnsen, Sven; Kelchtermans, Pieter; Pichler, Peter; van den Toorn, Henk W P; Staes, An; Vandenbussche, Jonathan; Mazanek, Michael; Taus, Thomas; Scheltema, Richard A; Kelstrup, Christian D; Gatto, Laurent; van Breukelen, Bas; Aiche, Stephan; Valkenborg, Dirk; Laukens, Kris; Lilley, Kathryn S; Olsen, Jesper V; Heck, Albert J R; Mechtler, Karl; Aebersold, Ruedi; Gevaert, Kris; Vizcaíno, Juan Antonio; Hermjakob, Henning; Kohlbacher, Oliver; Martens, Lennart

    2014-08-01

    Quality control is increasingly recognized as a crucial aspect of mass spectrometry based proteomics. Several recent papers discuss relevant parameters for quality control and present applications to extract these from the instrumental raw data. What has been missing, however, is a standard data exchange format for reporting these performance metrics. We therefore developed the qcML format, an XML-based standard that follows the design principles of the related mzML, mzIdentML, mzQuantML, and TraML standards from the HUPO-PSI (Proteomics Standards Initiative). In addition to the XML format, we also provide tools for the calculation of a wide range of quality metrics as well as a database format and interconversion tools, so that existing LIMS systems can easily add relational storage of the quality control data to their existing schema. We here describe the qcML specification, along with possible use cases and an illustrative example of the subsequent analysis possibilities. All information about qcML is available at http://code.google.com/p/qcml.

  8. qcML: An Exchange Format for Quality Control Metrics from Mass Spectrometry Experiments*

    PubMed Central

    Walzer, Mathias; Pernas, Lucia Espona; Nasso, Sara; Bittremieux, Wout; Nahnsen, Sven; Kelchtermans, Pieter; Pichler, Peter; van den Toorn, Henk W. P.; Staes, An; Vandenbussche, Jonathan; Mazanek, Michael; Taus, Thomas; Scheltema, Richard A.; Kelstrup, Christian D.; Gatto, Laurent; van Breukelen, Bas; Aiche, Stephan; Valkenborg, Dirk; Laukens, Kris; Lilley, Kathryn S.; Olsen, Jesper V.; Heck, Albert J. R.; Mechtler, Karl; Aebersold, Ruedi; Gevaert, Kris; Vizcaíno, Juan Antonio; Hermjakob, Henning; Kohlbacher, Oliver; Martens, Lennart

    2014-01-01

    Quality control is increasingly recognized as a crucial aspect of mass spectrometry based proteomics. Several recent papers discuss relevant parameters for quality control and present applications to extract these from the instrumental raw data. What has been missing, however, is a standard data exchange format for reporting these performance metrics. We therefore developed the qcML format, an XML-based standard that follows the design principles of the related mzML, mzIdentML, mzQuantML, and TraML standards from the HUPO-PSI (Proteomics Standards Initiative). In addition to the XML format, we also provide tools for the calculation of a wide range of quality metrics as well as a database format and interconversion tools, so that existing LIMS systems can easily add relational storage of the quality control data to their existing schema. We here describe the qcML specification, along with possible use cases and an illustrative example of the subsequent analysis possibilities. All information about qcML is available at http://code.google.com/p/qcml. PMID:24760958

  9. Role of brainstem sodium/proton exchanger 3 for breathing control during chronic acid base imbalance.

    PubMed

    Kiwull-Schöne, Heidrun; Kiwull, Peter; Frede, Stilla; Wiemann, Martin

    2007-09-01

    The sodium/proton exchanger (NHE) 3 is expressed in brainstem areas with prevalence for central chemosensitivity. Selective NHE3 inhibitors can evoke CO(2) mimetic responses both in vitro and in vivo, demonstrating the functional significance of this pH-regulating protein. Moreover, levels of NHE3 expression are inversely correlated to interindividual differences of baseline ventilation in conscious rabbits. We explored the influence of chronic acid-base disturbances on mRNA levels of brainstem NHE3 in relation to breathing control. Alveolar ventilation (Va), blood gases, systemic base excess (BE), and metabolic Vco(2) were determined in rabbits shortly after exposure to either CO(2)-enriched air for 3 days (n = 5) or to ammonium chloride with drinking water for 2 days (n = 6). Untreated animals served as controls (n = 24). NHE3 mRNA within the obex region was quantified by real-time reverse transcription-polymerase chain reaction. After chronic hypercapnia, we found a compensatory rise of BE (mean +/- SEM) to 5.3 +/- 0.5 mmol x L(-1) with slightly elevated Pa(CO(2)). Brainstem NHE3 mRNA as well as Va were not significantly different from control levels. In the NH(4)Cl group, arterial pH was approximately 0.09 units lower than control, and BE decreased to -6.5 +/- 1.6 mmol x L(-1) with slightly decreased Pa(CO(2)), but considerably reduced Va (by approximately 25%; P < 0.05) and Vco(2). Concomitantly, brainstem NHE3 mRNA had increased from control level of 1.45 +/- 0.19 to 3.64 +/- 0.37 fg cDNA/mug RNA; P < 0.01. Expression of brainstem NHE3 is up-regulated by chronic metabolic acidosis but not by prolonged hypercapnia. It is proposed that elevated brainstem NHE3 expression contributes to limit maladaptive hyperventilation during metabolic acidosis.

  10. A biological method of including mineralized human liquid and solid wastes into the mass exchange of bio-technical life support systems

    NASA Astrophysics Data System (ADS)

    Ushakova, S. A.; Tikhomirov, A. A.; Tikhomirova, N. A.; Kudenko, Yu. A.; Litovka, Yu. A.; Anishchenko, O. V.

    2012-10-01

    The main obstacle to using mineralized human solid and liquid wastes as a source of mineral elements for plants cultivated in bio-technical life support systems (BLSS) is that they contain NaCl. The purpose of this study is to determine whether mineralized human wastes can be used to prepare the nutrient solution for long-duration conveyor cultivation of uneven-aged wheat and Salicornia europaea L. plant community. Human solid and liquid wastes were mineralized by the method of "wet incineration" developed by Yu. Kudenko. They served as a basis for preparing the solutions that were used for conveyor-type cultivation of wheat community represented by 5 age groups, planted with a time interval of 14 days. Wheat was cultivated hydroponically on expanded clay particles. To reduce salt content of the nutrient solution, every two weeks, after wheat was harvested, 12 L of solution was removed from the wheat irrigation tank and used for Salicornia europaea cultivation in water culture in a conveyor mode. The Salicornia community was represented by 2 age groups, planted with a time interval of 14 days. As some portion of the nutrient solution used for wheat cultivation was regularly removed, sodium concentration in the wheat irrigation solution did not exceed 400 mg/L, and mineral elements contained in the removed portion were used for Salicornia cultivation. The experiment lasted 4 months. The total wheat biomass productivity averaged 30.1 g · m-2 · day-1, and the harvest index amounted to 36.8%. The average productivity of Salicornia edible biomass on a dry weight basis was 39.3 g · m-2 · day-1, and its aboveground mass contained at least 20% of NaCl. Thus, the proposed technology of cultivation of wheat and halophyte plant community enables using mineralized human wastes as a basis for preparing nutrient solutions and including NaCl in the mass exchange of the BLSS; moreover, humans are supplied with additional amounts of leafy vegetables.

  11. Effect of obstetric team training on team performance and medical technical skills: a randomised controlled trial.

    PubMed

    Fransen, A F; van de Ven, J; Merién, A E R; de Wit-Zuurendonk, L D; Houterman, S; Mol, B W; Oei, S G

    2012-10-01

    To determine whether obstetric team training in a medical simulation centre improves the team performance and utilisation of appropriate medical technical skills of healthcare professionals. Cluster randomised controlled trial. The Netherlands. The obstetric departments of 24 Dutch hospitals. The obstetric departments were randomly assigned to a 1-day session of multiprofessional team training in a medical simulation centre or to no such training. Team training was given with high-fidelity mannequins by an obstetrician and a communication expert. More than 6 months following training, two unannounced simulated scenarios were carried out in the delivery rooms of all 24 obstetric departments. The scenarios, comprising a case of shoulder dystocia and a case of amniotic fluid embolism, were videotaped. The team performance and utilisation of appropriate medical skills were evaluated by two independent experts. Team performance evaluated with the validated Clinical Teamwork Scale (CTS) and the employment of two specific obstetric procedures for the two clinical scenarios in the simulation (delivery of the baby with shoulder dystocia in the maternal all-fours position and conducting a perimortem caesarean section within 5 minutes for the scenario of amniotic fluid embolism). Seventy-four obstetric teams from 12 hospitals in the intervention group underwent teamwork training between November 2009 and July 2010. The teamwork performance in the training group was significantly better in comparison to the nontraining group (median CTS score: 7.5 versus 6.0, respectively; P = 0.014). The use of the predefined obstetric procedures for the two clinical scenarios was also significantly more frequent in the training group compared with the nontraining group (83 versus 46%, respectively; P = 0.009). Team performance and medical technical skills may be significantly improved after multiprofessional obstetric team training in a medical simulation centre. © 2012 The Authors BJOG An

  12. An examination of network position and childhood relational aggression: integrating resource control and social exchange theories.

    PubMed

    Neal, Jennifer Watling; Cappella, Elise

    2012-01-01

    Applying resource control theory and social exchange theory, we examined the social network conditions under which elementary age children were likely to engage in relational aggression. Data on classroom peer networks and peer-nominated behaviors were collected on 671 second- through fourth-grade children in 34 urban, low-income classrooms. Nested regression models with robust cluster standard errors demonstrated that the association between children's number of relationships and their levels of relational aggression was moderated by the number of relationships that their affiliates had. Children with more peer relationships (i.e., higher network centrality) exhibited higher levels of relational aggression, but only when these relationships were with peers who had fewer connections themselves (i.e., poorly connected peers). This finding remained significant even when controlling for common predictors of relational aggression including gender, overt aggression, prosocial behavior, victimization, social preference, and perceived popularity. Results are discussed in terms of their implications for advancing the literature on childhood relational aggression and their practical applications for identifying children at risk for these behaviors.

  13. Spacecraft Radiator Freeze Protection Using a Regenerative Heat Exchanger with Bypass Setpoint Temperature Control

    NASA Technical Reports Server (NTRS)

    Ungar, Eugene K.

    2008-01-01

    Spacecraft radiators are sized for their maximum heat load in their warmest thermal environment, but must operate at reduced heat loads and in colder environments. For systems where the radiator environment can be colder than the working fluid freezing temperature, radiator freezing becomes an issue. Radiator freezing has not been a major issue for the Space Shuttle and the International Space Station (ISS) active thermal control systems (ATCSs) because they operate in environments that are warm relative to the freezing point of their external coolants (Freon-21 and ammonia, respectively). For a vehicle that lands at the Lunar South Pole, the design thermal environment is 215K, but the radiator working fluid must also be kept from freezing during the 0 K sink of transit. A radiator bypass flow control design such as those used on the Space Shuttle and ISS requires more than 30% of the design heat load to avoid radiator freezing during transit - even with a very low freezing point working fluid. By changing the traditional ATCS architecture to include a regenerating heat exchanger inboard of the radiator and by using a regenerator bypass flow control valve to maintain system setpoint, the required minimum heat load can be reduced by more than half. This gives the spacecraft much more flexibility in design and operation. The present work describes the regenerator bypass ATCS setpoint control methodology. It includes analytical results comparing the performance of this system to the traditional radiator bypass system. Finally, a summary of the advantages of the regenerator bypass system are presented.

  14. Assessing technical performance in differential gene expression experiments with external spike-in RNA control ratio mixtures.

    PubMed

    Munro, Sarah A; Lund, Steven P; Pine, P Scott; Binder, Hans; Clevert, Djork-Arné; Conesa, Ana; Dopazo, Joaquin; Fasold, Mario; Hochreiter, Sepp; Hong, Huixiao; Jafari, Nadereh; Kreil, David P; Łabaj, Paweł P; Li, Sheng; Liao, Yang; Lin, Simon M; Meehan, Joseph; Mason, Christopher E; Santoyo-Lopez, Javier; Setterquist, Robert A; Shi, Leming; Shi, Wei; Smyth, Gordon K; Stralis-Pavese, Nancy; Su, Zhenqiang; Tong, Weida; Wang, Charles; Wang, Jian; Xu, Joshua; Ye, Zhan; Yang, Yong; Yu, Ying; Salit, Marc

    2014-09-25

    There is a critical need for standard approaches to assess, report and compare the technical performance of genome-scale differential gene expression experiments. Here we assess technical performance with a proposed standard 'dashboard' of metrics derived from analysis of external spike-in RNA control ratio mixtures. These control ratio mixtures with defined abundance ratios enable assessment of diagnostic performance of differentially expressed transcript lists, limit of detection of ratio (LODR) estimates and expression ratio variability and measurement bias. The performance metrics suite is applicable to analysis of a typical experiment, and here we also apply these metrics to evaluate technical performance among laboratories. An interlaboratory study using identical samples shared among 12 laboratories with three different measurement processes demonstrates generally consistent diagnostic power across 11 laboratories. Ratio measurement variability and bias are also comparable among laboratories for the same measurement process. We observe different biases for measurement processes using different mRNA-enrichment protocols.

  15. Does Encouragement Matter in Improving Gender Imbalances in Technical Fields? Evidence from a Randomized Controlled Trial

    PubMed Central

    Unkovic, Cait; Sen, Maya; Quinn, Kevin M.

    2016-01-01

    Does encouragement help address gender imbalances in technical fields? We present the results of one of the first and largest randomized controlled trials on the topic. Using an applied statistics conference in the social sciences as our context, we randomly assigned half of a pool of 3,945 graduate students to receive two personalized emails encouraging them to apply (n = 1,976) and the other half to receive nothing (n = 1,969). We find a robust, positive effect associated with this simple intervention and suggestive evidence that women responded more strongly than men. However, we find that women’s conference acceptance rates are higher within the control group than in the treated group. This is not the case for men. The reason appears to be that female applicants in the treated group solicited supporting letters at lower rates. Our findings therefore suggest that “low dose” interventions may promote diversity in STEM fields but may also have the potential to expose underlying disparities when used alone or in a non-targeted way. PMID:27097315

  16. Electric Power Research Institute, Environmental Control Technology Center report to the steering committee. Final technical report

    SciTech Connect

    1995-12-01

    Operations and maintenance continued this month at the Electric Power Research Institute`s Environmental Control Technology Center. Testing on the 4.0 MW Pilot Wet FGD unit continued with the Pilot High Velocity FGD (PHV) and the Trace Element Removal (TER) test blocks. In the High Velocity test block, SO{sub 2} removal and mist eliminator carryover rates were investigated while operating the absorber unit with various spray nozzle types and vertical mist eliminator sections. During the Trace Element Removal test block, the mercury measurements and control studies involving the EPA Method 29 continued with testing of several impinger capture solutions, and the use of activated carbon injection across the Pulse-Jet Fabric Filter (PJFF) unit. The 4.0 MW Spray Dryer Absorber System was utilized this month in the TER test configuration to inject and transfer activated carbon to the PJFF bags for downstream mercury capture. Work also began in December to prepare the 0.4 MW Mini-Pilot Absorber system for receipt of the B and W Condensing Heat Exchanger (CHX) unit to be used in the 1996 DOE/PRDA testing. The 1.0 MW Cold-Side Selective Catalytic Reduction (SCR) unit remained in cold-standby this month.

  17. Hemorrhage control for laparoscopic hepatectomy: technical details and predictive factors for intraoperative blood loss.

    PubMed

    Kawaguchi, Yoshikuni; Nomi, Takeo; Fuks, David; Mal, Frederic; Kokudo, Norihiro; Gayet, Brice

    2016-06-01

    Controlling bleeding during laparoscopic hepatectomy (LH) is technically demanding, but reportedly associated with less estimated blood loss (EBL) than open surgery. The present study aimed to describe and evaluate hemorrhage control techniques during LH and identify predictors of high intraoperative EBL. The data of 438 consecutive patients undergoing LH between 1995 and 2012 were reviewed. Bleeding control was facilitated by the proper use of hemostatic devices and surgical maneuvers unique to LH and by preserving intra-abdominal pressure. EBL was evaluated among three groups of 146 patients in each group: 1995-2006 (group A), 2006-2009 (group B), and 2009-2012 (group C). We also sought factors that predicted EBL ≥800 mL. Mean EBL decreased overtime from groups A to C: group A, 378 ± 619 mL; group B, 293 ± 391 mL; groups C, 257 ± 366 mL; P = 0.127. Transfusion rate was 6.7 % in group A, 5.5 % in group B, and 4.8 % in group C (P = 0.743). Hypertension (odds ratio (OR) 2.82, 95 % confidence interval CI 1.37-5.78; P = 0.006), preoperative chemotherapy (OR 2.55, 95 % CI 1.26-5.31; P = 0.009), resection of posterosuperior segments (OR 3.73, 95 % CI 1.33-12.17; P = 0.012), and major hepatectomy (OR 4.21, 95 % CI 1.64-13.02; P < 0.001) independently predicted high EBL. Improvements in bleeding control techniques over time have reduced EBL during LH. The use of these techniques and an understanding of the predictive factors for high EBL will help surgeons improve outcomes after LH.

  18. Design, integration and control of proton exchange membrane electrolyzer for wind based renewable energy applications

    NASA Astrophysics Data System (ADS)

    Harrison, Kevin W.

    This research endeavor began with the design and construction of a new hydrogen test facility at the National Renewable Energy Laboratory (NREL). To improve the electrical link of wind-based electrolysis the characterization of a proton exchange membrane (PEM) electrolyzer under varying input power was performed at NRELs new test facility. The commercially available electrolyzer from Proton Energy Systems (PES) was characterized using constant direct current (DC), sinusoidally varying DC, photovoltaics and variable magnitude and frequency energy from a 10 kW wind turbine. At rated stack current and ˜ 40°C the system efficiency of the commercial electrolyzer was measured to be 55%. At lower stack current it was shown that commercial electrolyzer system efficiency falls because of the continuous hydrogen purge (˜0.1 Nm3 hr-1) used to maintain the hydrogen desiccant drying system. A novel thermoelectric-based dew point controller is designed and modeled to reduce the penalty to renewable sources because they do not always operate at 100% of rated stack current. It is predicted that the thermoelectric design when operated 100% of the time at full current to the thermoelectric modules would consume 3.1 kWh kg -1 of hydrogen. Using the higher heating value of hydrogen and a stack efficiency of 60% to produce the hydrogen that is continuously vented, the desiccant system consumes about 5.7 kWh kg-1. Design of the UND electrolyzer sub-systems responsible for all aspects of water, power to the stack, and hydrogen conditioning enables more flexible and precise experimental data to be obtained than from an off-the-shelf system. Current-voltage (IV) characteristic curves were obtained on the UND system at temperatures between 7--70°C. The anode and cathode exchange current densities are fitted to 2.0 E-06 e0.043T and 0.12 e 0.026T A cm-2 respectively. Stack conductivity was fitted to 0.001T + 0.03 S cm-1. The three coefficients represent physical stack parameters and are

  19. Electrically controlled anion exchange based on polypyrrole and carbon nanotubes nanocomposite for perchlorate removal.

    PubMed

    Lin, Yuehe; Cui, Xiaoli; Bontha, Jagan

    2006-06-15

    A simple and highly effective process for perchlorate removal based on electrically switched ion exchange (ESIX) was developed by using polypyrrole (PPy) deposited on high surface area carbon nanotubes. The redox switching of conducting polymers such as polypyrrole is accompanied by the exchange of ions into or out of the polymer. This effect could be used for the development of an electrically switchable ion-exchanger for water purification, particularly for the removal of anions. In the research presented in this paper, the anion-exchange behavior and ion-exchange capacity of electrochemically prepared polypyrrole on glassy carbon electrodes with and without carbon nanotube (CNT) backbones are characterized using cyclic voltammetry and X-ray photoelectron spectroscopy. It has been found that the presence of carbon nanotube backbone results in an improvement in the anion exchange stability of polypyrrole, which may be due to the stronger interaction between carbon nanotubes and polypyrrole. Chronoamperometric studies show that the process of electrically switched anion exchange could be finished within 10 s. The selectivity of PPy/CNTs films for the perchlorate ion is demonstrated using cyclic voltammetry and X-ray photoelectron spectroscopy (XPS). The results of the present study point to the possibility of developing a green process for removing ClO4- from wastewater using such a novel nanostructured PPy/CNT composite thin film through an electrically switched anion exchange.

  20. Control of Advanced Reactor-Coupled Heat Exchanger System: Incorporation of Reactor Dynamics in System Response to Load Disturbances

    DOE PAGES

    Skavdahl, Isaac; Utgikar, Vivek; Christensen, Richard; ...

    2016-05-24

    We present an alternative control schemes for an Advanced High Temperature Reactor system consisting of a reactor, an intermediate heat exchanger, and a secondary heat exchanger (SHX) in this paper. One scheme is designed to control the cold outlet temperature of the SHX (Tco) and the hot outlet temperature of the intermediate heat exchanger (Tho2) by manipulating the hot-side flow rates of the heat exchangers (Fh/Fh2) responding to the flow rate and temperature disturbances. The flow rate disturbances typically require a larger manipulation of the flow rates than temperature disturbances. An alternate strategy examines the control of the cold outletmore » temperature of the SHX (Tco) only, since this temperature provides the driving force for energy production in the power conversion unit or the process application. The control can be achieved by three options: (1) flow rate manipulation; (2) reactor power manipulation; or (3) a combination of the two. The first option has a quicker response but requires a large flow rate change. The second option is the slowest but does not involve any change in the flow rates of streams. The final option appears preferable as it has an intermediate response time and requires only a minimal flow rate change.« less

  1. Gross primary production controls the subsequent winter CO2 exchange in a boreal peatland.

    PubMed

    Zhao, Junbin; Peichl, Matthias; Öquist, Mats; Nilsson, Mats B

    2016-12-01

    In high-latitude regions, carbon dioxide (CO2 ) emissions during the winter represent an important component of the annual ecosystem carbon budget; however, the mechanisms that control the winter CO2 emissions are currently not well understood. It has been suggested that substrate availability from soil labile carbon pools is a main driver of winter CO2 emissions. In ecosystems that are dominated by annual herbaceous plants, much of the biomass produced during the summer is likely to contribute to the soil labile carbon pool through litter fall and root senescence in the autumn. Thus, the summer carbon uptake in the ecosystem may have a significant influence on the subsequent winter CO2 emissions. To test this hypothesis, we conducted a plot-scale shading experiment in a boreal peatland to reduce the gross primary production (GPP) during the growing season. At the growing season peak, vascular plant biomass in the shaded plots was half that in the control plots. During the subsequent winter, the mean CO2 emission rates were 21% lower in the shaded plots than in the control plots. In addition, long-term (2001-2012) eddy covariance data from the same site showed a strong correlation between the GPP (particularly the late summer and autumn GPP) and the subsequent winter net ecosystem CO2 exchange (NEE). In contrast, abiotic factors during the winter could not explain the interannual variation in the cumulative winter NEE. Our study demonstrates the presence of a cross-seasonal link between the growing season biotic processes and winter CO2 emissions, which has important implications for predicting winter CO2 emission dynamics in response to future climate change. © 2016 John Wiley & Sons Ltd.

  2. What Animated Illustrations Conditions Can Improve Technical Document Comprehension in Young Students? Format, Signaling and Control of the Presentation

    ERIC Educational Resources Information Center

    Boucheix, Jean-Michel; Guignard, Helene

    2005-01-01

    We study the comprehension of a multimedia technical document about gear functioning by young pupils. The research is focused on the effect of three factors on the construction of a mental model: illustration format (animated versus static) signaling cues (presence versus absence) learner-control of information delivery (three rhythms of…

  3. Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). PRE-SPC 11: SPC & Graphs. Instructor Book.

    ERIC Educational Resources Information Center

    Averitt, Sallie D.

    This instructor guide, which was developed for use in a manufacturing firm's advanced technical preparation program, contains the materials required to present a learning module that is designed to prepare trainees for the program's statistical process control module by improving their basic math skills in working with line graphs and teaching…

  4. System Control Facilities: Head-Ends and Central Processors. A Survey of Technical Requirements for Broadband Cable Teleservices; Volume Four.

    ERIC Educational Resources Information Center

    Smith, Ernest K.; And Others

    The system control facilities in broadband communication systems are discussed in this report. These facilities consist of head-ends and central processors. The first section summarizes technical problems and needs, and the second offers a cursory overview of systems, along with an incidental mention of processors. Section 3 looks at the question…

  5. Materials Testing and Quality Control Soils, 3-28. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This instructional package on material testing and quality control of soils has been adapted from military curriculum materials for use in technical and vocational education programs. This short course presents basic information on soils as well as exploration, field identification, and laboratory procedures that will enable students completing…

  6. Geophysical controls of aquifer-river exchange flow patterns in a UK lowland meandering river.

    NASA Astrophysics Data System (ADS)

    Dara, Rebwar; Krause, Stefan; Rivett, Michael

    2016-04-01

    The deposition of fine particles (clay and silt) and organic matters in alluvial sediments can substantially reduce the permeability of streambed sediments and extend towards the wider floodplain. The resulting hydraulic conductivity patterns within the streambed and floodplain have been shown to control both location as well as intensity of hyporheic exchange in many lowland rivers. The aim of the study is to investigate the variability in streambed permeability fields in an unprecedented spatial resolution and quantify the impacts on controlling hyporheic exchange fluxes in the River Tern, a UK lowland meandering stream. Geophysical surveys were conducted deploying Ground Penetrating Radar (GPR) in conjunction with geological information derived from core logs and bank exposures for mapping shallow subsurface structural heterogeneity. The GPR survey deployed a pulse EKKO pro equipped with a shielded 250 MHz antenna. For the floodplain survey, GPR profiles of 12 NE-SW and 6 NW- SE orientation profiles were taken creating a raster of approximately 10 m. The riparian terrestrial GPR surveys were accompanied by a longitudinal in channel GPR survey for which the antenna was deployed on a floating device. At locations identified to be representative for the range of streambed hydrofacies identified by GPR in investigated stream reach, multi-level mini-piezometer networks were installed in the streambed for monitoring groundwater-surface water exchange fluxes, and conducting dilution tracer tests for quantification of residence time distributions at the aquifer-river interface. Quasi-three-dimensional GPR profiles from closely spaced grids of 2D GPR data of floodplain deposits indicated a range of different radar facies and helped to delineate the type and extend of high and low conductive materials. The results of longitudinal GPR survey along a 240 m section of the river channel revealed that areas rich in low conductivity layers such as organic peat and clay lenses

  7. Corporate Characteristics and Internal Control Information Disclosure- Evidence from Annual Reports in 2009 of Listed Companies in Shenzhen Stock Exchange

    NASA Astrophysics Data System (ADS)

    Xiaowen, Song

    Under the research framework of internal control disclosure and combined the current economic situation, the paper empirically analyzes the relationship between corporate characteristics and internal control information disclosure. The paper selects 647 A share companies listed in Shenzhen Stock Exchanges in 2009 as a sample. The results show: (1) the companies with excellent performance and high liquidity tend to disclose more internal control information; (2) the companies with the high leverage and also issued B shares are not willing to disclosure internal control information; (3) the companies sizes and companies which have hired Four-big accounting firms have no significant effects on internal control disclosure.

  8. Fouling on ion-exchange membranes: Classification, characterization and strategies of prevention and control.

    PubMed

    Mikhaylin, Sergey; Bazinet, Laurent

    2016-03-01

    The environmentally friendly ion-exchange membrane (IEM) processes find more and more applications in the modern industries in order to demineralize, concentrate and modify products. Moreover, these processes may be applied for the energy conversion and storage. However, the main drawback of the IEM processes is a formation of fouling, which significantly decreases the process efficiency and increases the process cost. The present review is dedicated to the problematic of IEM fouling phenomena. Firstly, the major types of IEM fouling such as colloidal fouling, organic fouling, scaling and biofouling are discussed along with consideration of the main factors affecting fouling formation and development. Secondly, the review of the possible methods of IEM fouling characterization is provided. This section includes the methods of fouling visualization and characterization as well as methods allowing investigations of characteristics of the fouled IEMs. Eventually, the reader will find the conventional and modern strategies of prevention and control of different fouling types. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. A novel design of the heat exchanger of an aircraft's environmental controller

    NASA Astrophysics Data System (ADS)

    Shahbazian, Negin

    Redesign of a heat exchanger chassis of an aircraft's environmental controller developed by Honeywell was carried out using finite element analysis (FEA) to reduce overall cost and weight. Eight design alternatives were proposed to replace the current design and were evaluated using a decision matrix. Selected design involved introduction of bolted flanges into the chassis. Von-Mises stresses in the flanges and shear and tensile forces in the bolts were obtained by FEA using ANSYS. Flanges were further modified using safety margin and weight as optimization factors. The optimized flange contains a fluid passage with 0.08in wall thickness reduction and 0.14in passage length reduction. Furthermore, the overall weight was reduced by 0.026kg. After optimization, the margin of safety was improved from 0.041 to 0.580 for maximum operating pressure, and from -0.297 to 0.067 for burst pressure. The novel design accomplished weight and cost reduction along with improving the margins of safety.

  10. Control of lymphocyte shape and the chemotactic response by the GTP exchange factor Vav.

    PubMed

    Vicente-Manzanares, Miguel; Cruz-Adalia, Aranzazu; Martín-Cófreces, Noa B; Cabrero, José R; Dosil, Mercedes; Alvarado-Sánchez, Brenda; Bustelo, Xosé R; Sánchez-Madrid, Francisco

    2005-04-15

    Rho GTPases control many facets of cell polarity and migration; namely, the reorganization of the cellular cytoskeleton to extracellular stimuli. Rho GTPases are activated by GTP exchange factors (GEFs), which induce guanosine diphosphate (GDP) release and the stabilization of the nucleotide-free state. Thus, the role of GEFs in the regulation of the cellular response to extracellular cues during cell migration is a critical step of this process. In this report, we have analyzed the activation and subcellular localization of the hematopoietic GEF Vav in human peripheral blood lymphocytes stimulated with the chemokine stromal cell-derived factor-1 (SDF-1alpha). We show a robust activation of Vav and its redistribution to motility-associated subcellular structures, and we provide biochemical evidence of the recruitment of Vav to the membrane of SDF-1alpha-activated human lymphocytes, where it transiently interacts with the SDF-1alpha receptor CXCR4. Overexpression of a dominant negative form of Vav abolished lymphocyte polarization, actin polymerization, and migration. SDF-1alpha-mediated cell polarization and migration also were impaired by overexpression of an active, oncogenic Vav, although the mechanism appears to be different. Together, our data postulate a pivotal role for Vav in the transmission of the migratory signal through the chemokine receptor CXCR4.

  11. Water and nitrogen availability co-control ecosystem CO2 exchange in a semiarid temperate steppe.

    PubMed

    Zhang, Xiaolin; Tan, Yulian; Li, Ang; Ren, Tingting; Chen, Shiping; Wang, Lixin; Huang, Jianhui

    2015-10-23

    Both water and nitrogen (N) availability have significant effects on ecosystem CO2 exchange (ECE), which includes net ecosystem productivity (NEP), ecosystem respiration (ER) and gross ecosystem photosynthesis (GEP). How water and N availability influence ECE in arid and semiarid grasslands is still uncertain. A manipulative experiment with additions of rainfall, snow and N was conducted to test their effects on ECE in a semiarid temperate steppe of northern China for three consecutive years with contrasting natural precipitation. ECE increased with annual precipitation but approached peak values at different precipitation amount. Water addition, especially summer water addition, had significantly positive effects on ECE in years when the natural precipitation was normal or below normal, but showed trivial effect on GEP when the natural precipitation was above normal as effects on ER and NEP offset one another. Nitrogen addition exerted non-significant or negative effects on ECE when precipitation was low but switched to a positive effect when precipitation was high, indicating N effect triggered by water availability. Our results indicate that both water and N availability control ECE and the effects of future precipitation changes and increasing N deposition will depend on how they can change collaboratively in this semiarid steppe ecosystem.

  12. Geologically controlled bi-directional exchange of groundwater with a hypersaline lake in the Canadian prairies

    NASA Astrophysics Data System (ADS)

    Bentley, Laurence R.; Hayashi, Masaki; Zimmerman, Elena P.; Holmden, Chris; Kelley, Lynn I.

    2016-06-01

    Hypersaline lakes occur in hydrologically closed basins due to evaporitic enrichment of dissolved salts transported to the lakes by surface water and groundwater. At the hypersaline Lydden Lake in Saskatchewan, Canada, groundwater/lake-water interaction is strongly influenced by the geological heterogeneity of glacial deposits, whereby a highly permeable glaciofluvial sand/gravel deposit is underlain by glaciolacustrine deposits consisting of dense clay interspersed with silt/sand lenses. Pressure head distribution in a near shore area indicates a bi-directional flow system. It consists of topographically driven flow of fresh groundwater towards the lake in the sand/gravel aquifer and density-driven, landward flow of saline groundwater in the underlying glaciolacustrine deposits. Electrical resistivity tomography, and chemical and isotopic composition of groundwater clearly show the landward intrusion of saline water in the heterogeneous unit. The feasibility of bi-directional flow and transport is supported by numerical simulations of density-coupled groundwater flow and transport. The results suggest that the geologically controlled groundwater exchange processes have substantial influences on both inputs and outputs of dissolved minerals in hypersaline lakes in closed basins.

  13. Sequential Solvent Exchange Method for Controlled Exfoliation of MoS2 Suitable for Phototransistor Fabrication.

    PubMed

    Ghasemi, Foad; Mohajerzadeh, Shams

    2016-11-16

    In this study, flakes of molybdenum disulfide (MoS2) with controlled size and thickness are prepared through sequential solvent exchange method by sonication in dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP) solvents. While NMP acts more effectively in reducing the thickness of flakes, DMF shows better potential in conserving the lateral size of nanosheets. The distribution of size and thickness of nanoflakes as a function of sonication time verifies that extended sonication results in dramatic drop of the dimension of the exfoliated flakes. This technique leads to the formation of few-layered MoS2 flakes without further drop of their lateral dimensions. It has been observed that by exposing the bulk MoS2 powders to oxygen plasma, the exfoliation process is accelerated without converting to 2H-MoS2 structures. Finally, a phototransistor has been fabricated based on few-layered MoS2 layers with a field effect mobility of ∼2.1 cm(2) V(-1) s(-1) showing a high response to laser excitation of 532 nm wavelength.

  14. Parameter optimization of measuring and control elements in the monitoring systems of complex technical objects

    NASA Astrophysics Data System (ADS)

    Nekrylov, Ivan; Korotaev, Valery; Blokhina, Anastasia; Kleshchenok, Maksim

    2017-06-01

    In the world is the widespread adoption of measuring equipment of new generation, which is characterized by small size, high automation level, a multi-channel, digital filtering, satellite synchronization, wireless communication, digital record in long-term memory with great resource, powered by long-lived sources, etc. However, modern equipment base of the Russian institutions and the level of development of technical facilities and measuring technologies lag far behind developed countries. For this reason, the vacated niches are actively developed by foreign companies. For example, more than 70% instrumentation performing works on the territory of Russia, equipped with imported equipment (products of Sweden and Germany companies); the amount of work performed with German equipment is more than 70% of the total volume of these works; more than 80% of industrial measurements are performed using HEXAGON equipment (Sweden). These trends show that the Russian sector of measuring technology gradually become import-dependent, which poses a threat to the economic security of the country and consistent with national priorities. The results of the research will allow to develop the theory of formation of control systems of the displacement with high accuracy and unattainable for the existing analogue ergonomic and weight characteristics combined with a comparable or lower cost. These advantages will allow you to be successful competition, and eventually to supplant the existing system, which had no fundamental changes in the last 20 years and, therefore, retained all the drawbacks: large size and weight, high power consumption, the dependence on magnetic fields

  15. Controllable exchange bias in Fe/metamagnetic FeRh bilayers

    SciTech Connect

    Suzuki, Ippei; Hamasaki, Yosuke; Itoh, Mitsuru; Taniyama, Tomoyasu

    2014-10-27

    We report the studies of tuning the exchange bias at ferromagnetic Fe/metamagnetic FeRh bilayer interfaces. Fe/FeRh(111) bilayers show exchange bias in the antiferromagnetic state of FeRh while no exchange bias occurs at Fe/FeRh(001) interface. The contrasting results are attributed to the spin configurations of FeRh at the interface, i.e., the uncompensated ferromagnetic spin configuration of FeRh appears exclusively for (111) orientation. The exchange bias disappears as the bilayers are warmed above the antiferromagnetic-ferromagnetic transition temperature. The direction of the exchange bias for Fe/FeRh(111) is also found to be perpendicular to the cooling-field direction, in contrast to the commonly observed direction of exchange bias for ferromagnetic/antiferromagnetic interfaces. In view of these results, the exchange bias in Fe/FeRh bilayers with the (111) crystallographic orientation should be useful for the design of rapid writing technology for magnetic information devices.

  16. Controls on mangrove forest-atmosphere carbon dioxide exchanges in western Everglades National Park

    USGS Publications Warehouse

    Barr, Jordan G.; Engel, Vic; Fuentes, Jose D.; Zieman, Joseph C.; O'Halloran, Thomas L.; Smith, Thomas J.; Anderson, Gordon H.

    2010-01-01

    We report on net ecosystem production (NEP) and key environmental controls on net ecosystem exchange (NEE) of carbon dioxide (CO2) between a mangrove forest and the atmosphere in the coastal Florida Everglades. An eddy covariance system deployed above the canopy was used to determine NEE during January 2004 through August 2005. Maximum daytime NEE ranged from -20 to -25 μmol (CO2) m-2 s-1 between March and May. Respiration (Rd) was highly variable (2.81 ± 2.41 μmol (CO2) m-2 s-1), reaching peak values during the summer wet season. During the winter dry season, forest CO2 assimilation increased with the proportion of diffuse solar irradiance in response to greater radiative transfer in the forest canopy. Surface water salinity and tidal activity were also important controls on NEE. Daily light use efficiency was reduced at high (>34 parts per thousand (ppt)) compared to low (d by ~0.9 μmol (CO2) m-2 s-1 and nighttime Rd by ~0.5 μmol (CO2) m-2 s-1. The forest was a sink for atmospheric CO2, with an annual NEP of 1170 ± 127 g C m-2 during 2004. This unusually high NEP was attributed to year-round productivity and low ecosystem respiration which reached a maximum of only 3 g C m-2 d-1. Tidal export of dissolved inorganic carbon derived from belowground respiration likely lowered the estimates of mangrove forest respiration. These results suggest that carbon balance in mangrove coastal systems will change in response to variable salinity and inundation patterns, possibly resulting from secular sea level rise and climate change.

  17. Controls for ecosystem methane exchange are time-scale specifc and shift during the growing season of a temperate fen

    NASA Astrophysics Data System (ADS)

    Sachs, T.; Koebsch, F.; Jurasinski, G.; Koch, M.; Hofmann, J.; Glatzel, S.

    2014-12-01

    Wetlands are the largest natural sources for atmospheric methane (CH4). In wetlands with permanent shallow inundation, the seasonal variation of CH4 exchange is mainly controlled by temperature and phenology. In addition, ecosystem CH4 exchange varies considerably on smaller temporal scales such as days or weeks. Several single processes that control CH4 emissions on the local soil-plant-atmosphere continuum are well investigated, but their interaction on ecosystem level is not well understood yet. We applied wavelet analysis to a quasi-continuous Eddy Covariance CH4 flux time series to describe the temporal variation of ecosystem CH4 exchange within the growing season of a permanently inundated temperate fen. Moreover, we addressed time scale-specific controls and investigated whether their impact changes during the course of the growing season. On large time scales of two weeks to three months, temperature explained most of the variation in ecosystem CH4 exchange. In general, the temperature in the shallow water column had the largest impact as explanatory variable, however, air temperature and soil temperature became increasingly important as explanatory variables when water level dropped slightly up to June. The diurnal variation of ecosystem CH4 exchange shifted during the course of the growing season: During a short time period at the end of April, plant activity (expressed by canopy photosynthesis) caused a diurnal variation of ecosystem CH4 exchange with peak time around noon. In the following weeks, the daily cycle of convective mixing within the water column (expressed by the water temperature gradient) gradually gained importance and caused high night-time CH4 emissions, thereby levelling off the diurnal CH4 emission pattern. Moreover, shear-induced turbulence caused short-term fluctuations of ecosystem CH4 exchange on time scales up to two hours. Our study highlights the need for multi-scale approaches that consider the non-stationarity of the

  18. [Characteristics of mercury exchange flux between soil and atmosphere under the snow retention and snow melting control].

    PubMed

    Zhang, Gang; Wang, Ning; Ai, Jian-Chao; Zhang, Lei; Yang, Jing; Liu, Zi-Qi

    2013-02-01

    Jiapigou gold mine, located in the upper Songhua River, was once the largest mine in China due to gold output, where gold extraction with algamation was widely applied to extract gold resulting in severe mercury pollution to ambient environmental medium. In order to study the characteristics of mercury exchange flux between soil (snow) and atmosphere under the snow retention and snow melting control, sampling sites were selected in equal distances along the slope which is situated in the typical hill-valley terrain unit. Mercury exchange flux between soil (snow) and atmosphere was determined with the method of dynamic flux chamber and in all sampling sites the atmosphere concentration from 0 to 150 cm near to the earth in the vertical direction was measured. Furthermore, the impact factors including synchronous meteorology, the surface characteristics under the snow retention and snow melting control and the mercury concentration in vertical direction were also investigated. The results are as follows: During the period of snow retention and melting the air mercury tends to gather towards valley bottom along the slope and an obvious deposit tendency process was found from air to the earth's surface under the control of thermal inversion due to the underlying surface of cold source (snow surface). However, during the period of snow melting, mercury exchange flux between the soil and atmosphere on the surface of the earth with the snow being melted demonstrates alternative deposit and release processes. As for the earth with snow covered, the deposit level of mercury exchange flux between soil and atmosphere is lower than that during the period of snow retention. The relationship between mercury exchange flux and impact factors shows that in snow retention there is a remarkable negative linear correlation between mercury exchange flux and air mercury concentration as well as between the former and the air temperature. In addition, in snow melting mercury exchange

  19. Imaging and Electric Control of Boundary Magnetization and Exchange Bias in Chromia and Chromia/CoPd

    NASA Astrophysics Data System (ADS)

    He, Xi; Wu, Ning; Wang, Yi; Wysocki, Alekasander; Komesu, Takashi; Belashchenko, Kirill; Dowben, Peter; Binek, Christian; Lanke, Uday; Caruso, Anthony; Vescovo, Elio

    2011-03-01

    Promising spintronic concepts utilize electric control of boundary magnetization. Symmetry arguments predict that the magnetoelectric antiferromagnet (AF) Cr 2 O3 , has a roughness insensitive surface magnetization which is coupled to the bulk AF order parameter. We provide macroscopic and microscopic evidence for this surface magnetization and its electric control. The latter is exploited in perpendicular exchange bias heterostructures where a ferromagnetic Pd/Co multilayer is deposited on the (0001) surface of a Cr 2 O3 single crystal. These heterostructures show reversible, room-temperature voltage-controlled switching of the exchange-bias field between positive and negative values. This work is supported by NSF Career, NSF MRSEC, NRI, and Research Corporation. Xi He, et al. Nature Materials 9, 579 (2010)

  20. A Middleware for the Controlled Information Exchange Between Online Games and Internet Applications

    NASA Astrophysics Data System (ADS)

    Bergsträßer, Sonja; Hildebrandt, Tomas; Rensing, Christoph; Steinmetz, Ralf

    Multiplayer Online Games (MOGs) are a thriving market leading to a multiplicity of game related internet applications. Enabling information exchange between games and these applications is essential, but still an unsolved challenge. Our Virtual Context Based Service (VCBS) middleware enables such an information exchange. The VCBS middleware is an interface between games and other internet applications, which also supports community activities. In this paper we describe the architecture of the VCBS middleware and its components, and introduce our concept for generic MOG interfaces.

  1. Solid oxide fuel cell cathode infiltrate particle size control and oxygen surface exchange resistance determination

    NASA Astrophysics Data System (ADS)

    Burye, Theodore E.

    Over the past decade, nano-sized Mixed Ionic Electronic Conducting (MIEC) -- micro-sized Ionic Conducting (IC) composite cathodes produced by the infiltration method have received much attention in the literature due to their low polarization resistance (RP) at intermediate (500-700°C) operating temperatures. Small infiltrated MIEC oxide nano-particle size and low intrinsic MIEC oxygen surface exchange resistance (Rs) have been two critical factors allowing these Nano-Micro-Composite Cathodes (NMCCs) to achieve high performance and/or low temperature operation. Unfortunately, previous studies have not found a reliable method to control or reduce infiltrated nano-particle size. In addition, controversy exists on the best MIEC infiltrate composition because: 1) Rs measurements on infiltrated MIEC particles are presently unavailable in the literature, and 2) bulk and thin film Rs measurements on nominally identical MIEC compositions often vary by up to 3 orders of magnitude. Here, two processing techniques, precursor nitrate solution desiccation and ceria oxide pre-infiltration, were developed to systematically produce a reduction in the average La0.6Sr0.4Co0.8Fe 0.2O3-delta (LSCF) infiltrated nano-particle size from 50 nm to 22 nm. This particle size reduction reduced the SOFC operating temperature, (defined as the temperature where RP=0.1 Ocm 2) from 650°C to 540°C. In addition, Rs values for infiltrated MIEC particles were determined for the first time through finite element modeling calculations on 3D Focused Ion Beam-Scanning Electron Microscope (FIB-SEM) reconstructions of electrochemically characterized infiltrated electrodes.

  2. Electrically Switched Cesium Ion Exchange

    SciTech Connect

    JPH Sukamto; ML Lilga; RK Orth

    1998-10-23

    This report discusses the results of work to develop Electrically Switched Ion Exchange (ESIX) for separations of ions from waste streams relevant to DOE site clean-up. ESIX combines ion exchange and electrochemistry to provide a selective, reversible method for radionuclide separation that lowers costs and minimizes secondary waste generation typically associated with conventional ion exchange. In the ESIX process, an electroactive ion exchange film is deposited onto. a high surface area electrode, and ion uptake and elution are controlled directly by modulating the potential of the film. As a result, the production of secondary waste is minimized, since the large volumes of solution associated with elution, wash, and regeneration cycles typical of standard ion exchange are not needed for the ESIX process. The document is presented in two parts: Part I, the Summary Report, discusses the objectives of the project, describes the ESIX concept and the approach taken, and summarizes the major results; Part II, the Technology Description, provides a technical description of the experimental procedures and in-depth discussions on modeling, case studies, and cost comparisons between ESIX and currently used technologies.

  3. Enabling a flexible exchange of energy of a photovoltaic plant with the grid by means of a controlled storage system

    NASA Astrophysics Data System (ADS)

    Lazzari, R.; Parma, C.; De Marco, A.; Bittanti, S.

    2015-07-01

    In this paper, we describe a control strategy for a photovoltaic (PV) power plant equipped with an energy storage system (ESS), based on lithium-ion battery. The plant consists of the following units: the PV generator, the energy storage system, the DC-bus and the inverter. The control, organised in a hierarchical manner, maximises the self-consumption of the local load unit. In particular, the ESS action performs power balance in case of low solar radiation or surplus of PV generation, thus managing the power exchange variability at the plant with the grid. The implemented control strategy is under testing in RSE pilot test facility in Milan, Italy.

  4. Comparison of 2 techniques of laryngeal tube exchange in a randomized controlled simulation study.

    PubMed

    Budde, Arne O; Schwarz, Adam; Dalal, Priti G; Sinz, Elizabeth H; Vaida, Sonia J

    2015-02-01

    Laryngeal tubes (LT) are often used as rescue airway devices. Among prehospital medical personnel, the success rates are high and significantly faster compared to an endotracheal tube (ETT). Therefore, LTs are increasingly used in the prehospital setting. The exchange of an LT for an ETT may often be desirable. Two fiberoptic bronchoscope-facilitated techniques have been described to exchange an LT for an ETT: an intraluminal technique using an Aintree intubating catheter and an extraluminal technique using a nasal route alongside the LT. In this randomized cross-over mannequin study, we compared the intraluminal with the extraluminal exchange technique. The primary outcome was time to achieve an effective airway through an ETT. We hypothesized that the intraluminal technique would be significantly faster. Thirty anesthesia providers were recruited to the study. Each participant attempted both techniques in an intubation simulation model. The tube exchange time was recorded from picking up the fiberoptic bronchoscope until confirmation of ventilation with the ETT. Four participants in each group had a failed attempt at intubation. Time to establish an endotracheal intubation was significantly shorter with the intraluminal technique vs the extraluminal technique (77.5 vs 140 seconds; P=.03). Based on the results of our study, we suggest that the intraluminal technique may be a suitable alternative for a fiberoptic-guided rapid exchange of an LT for an ETT to establish an effective airway in a challenging situation. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Controls on circulation, cross-shelf exchange, and dense water formation in an Antarctic polynya

    NASA Astrophysics Data System (ADS)

    Snow, K.; Sloyan, B. M.; Rintoul, S. R.; Hogg, A. McC.; Downes, S. M.

    2016-07-01

    Circulation on the Antarctic continental shelf influences cross-shelf exchange, Antarctic Bottom Water formation, and ocean heat flux to floating ice shelves. The physical processes driving the shelf circulation and its seasonal and interannual variability remain poorly understood. We use a unique time series of repeat hydrographic observations from the Adélie Land continental shelf and a box inverse model to explore the relationship between surface forcing, shelf circulation, cross-shelf exchange, and dense water formation. A wind-driven northwestward coastal current, set up by onshore Ekman transport, dominates the summer circulation. During winter, strong buoyancy loss creates dense shelf water. This dense water flows off the shelf, with a compensating on-shelf flow that is an order of magnitude larger in winter than in summer. The results demonstrate the importance of winter buoyancy loss in driving the shelf circulation and cross-shelf exchange, as well as dense water mass formation.

  6. Neural Control of Gas Exchange Patterns in Insects: Locust Density-Dependent Phases as a Test Case

    PubMed Central

    Berman, Tali S.; Ayali, Amir; Gefen, Eran

    2013-01-01

    The adaptive significance of discontinuous gas exchange cycles (DGC) in insects is contentious. Based on observations of DGC occurrence in insects of typically large brain size and often socially-complex life history, and spontaneous DGC in decapitated insects, the neural hypothesis for the evolution of DGC was recently proposed. It posits that DGC is a non-adaptive consequence of adaptive down-regulation of brain activity at rest, reverting ventilatory control to pattern-generating circuits in the thoracic ganglia. In line with the predictions of this new hypothesis, we expected a higher likelihood of DGC in the gregarious phase of the desert locust (Schistocerca gregaria, Orthoptera), which is characterized by a larger brain size and increased sensory sensitivity compared with the solitary phase. Furthermore, surgical severing of the neural connections between head and thoracic ganglia was expected to increase DGC prevalence in both phases, and to eliminate phase-dependent variation in gas exchange patterns. Using flow-through respirometry, we measured metabolic rates and gas exchange patterns in locusts at 30°C. In contrast to the predictions of the neural hypothesis, we found no phase-dependent differences in DGC expression. Likewise, surgically severing the descending regulation of thoracic ventilatory control did not increase DGC prevalence in either phase. Moreover, connective-cut solitary locusts abandoned DGC altogether, and employed a typical continuous gas exchange pattern despite maintaining metabolic rate levels of controls. These results are not consistent with the predictions of the neural hypothesis for the evolution of DGC in insects, and instead suggest neural plasticity of ventilatory control. PMID:23555850

  7. Twin plane decoration of silver nanorods with palladium by galvanic exchange at a controlled rate.

    PubMed

    Sławiński, Grzegorz W; Ivanova, Olga S; Zamborini, Francis P

    2011-11-01

    Here we describe the galvanic exchange of surface-grown Ag nanorods (NRs) and nanowires (NWs) with PdCl(4)(2-) as a function of the PdCl(4)(2-) concentration. The morphology of the resulting AgPd alloy nanostructures depends on the galvanic exchange rate, which increases with increasing PdCl(4)(2-) concentration over a specific concentration range. When the concentration of PdCl(4)(2-) exceeds 7.5 × 10(-5) M (or ratio of moles of PdCl(4)(2-) in solution to moles of Ag on the surface > 542), rapid galvanic exchange results in Pd deposition over the entire Ag nanostructure in the early stages of exchange. When the concentration of PdCl(4)(2-) is in the range of 1.0 × 10(-5) to 5.0 × 10(-5) M (moles of PdCl(4)(2-) in solution to moles of Ag on the surface = 13-54), Pd deposition occurs preferentially at high energy twin plane defects in the form of well-spaced nanoparticles during the early stages of exchange. In later stages, the Pd deposits grow and coalescence into a rough shell, and etching of the Ag leads to a presumably hollow nanostructure. Composition analysis by linear sweep voltammetry as a function of time shows that the galvanic exchange rate is much slower than the diffusion-limited rate and, when correlated with UV-vis spectroscopy, shows that less than 10% Pd in the nanostructure completely dampens the Ag-localized surface plasmon band.

  8. Kinetically controlled patterning of highly cross-linked phosphonium photopolymers using simple anion exchange.

    PubMed

    Guterman, Ryan; Gillies, Elizabeth R; Ragogna, Paul J

    2015-05-12

    A phosphonium salt possessing three methacrylate groups has been incorporated into a photopolymeric system to generate highly cross-linked polyelectrolyte networks. Emergent chemical and physical properties in the polymers were observed and attributed to the tandem increase in cross-link density and ion-content upon incorporation of the self-cross-linking cation. Anion-exchange with bis(trifluoromethylsulfonyl)imide or dodecylbenzenesulfonate resulted in significant differences in wettability and ion-exchange behavior. The passivating effects of dodecylbenzenesulfonate were utilized to selectively pattern fluorescein dye into the polymer network, highlighting a new patterning procedure using ionic-bond forming reactions.

  9. The mitochondrial Na+/Ca2+ exchanger plays a key role in the control of cytosolic Ca2+ oscillations.

    PubMed

    Hernández-SanMiguel, Esther; Vay, Laura; Santo-Domingo, Jaime; Lobatón, Carmen D; Moreno, Alfredo; Montero, Mayte; Alvarez, Javier

    2006-07-01

    There is increasing evidence that mitochondria play an important role in the control of cytosolic Ca2+ signaling. We show here that the main mitochondrial Ca2+-exit pathway, the mitochondrial Na+/Ca2+ exchanger, controls the pattern of cytosolic Ca2+ oscillations in non-excitable cells. In HeLa cells, the inhibitor of the mitochondrial Na+/Ca2+ exchanger CGP37157 changed the pattern of the oscillations induced by histamine from a high-frequency irregular one to a lower frequency baseline spike type, surprisingly with little changes in the average Ca2+ values of a large cell population. In human fibroblasts, CGP37157 increased the frequency of the baseline oscillations in cells having spontaneous activity and induced the generation of oscillations in cells without spontaneous activity. This effect was dose-dependent, disappeared when the inhibitor was washed out and was not mimicked by mitochondrial depolarization. CGP37157 increased mitochondrial [Ca2+] and ATP production in histamine-stimulated HeLa cells, but the effect on ATP production was only transient. CGP37157 also activated histamine-induced Ca2+ release from the endoplasmic reticulum and increased the size of the cytosolic Ca2+ peak induced by histamine in HeLa cells. Our results suggest that the mitochondrial Na+/Ca2+ exchanger directly modulates inositol 1,4,5-trisphosphate-induced Ca2+ release and in that way controls cytosolic Ca2+ oscillations.

  10. Environmental Control of Net Ecosystem Carbon Dioxide Exchange in Contrasting Peatlands in northern Alberta, Canada

    NASA Astrophysics Data System (ADS)

    Syed, K. H.; Carlson, P. J.; Glenn, A. J.; Flanagan, L. B.

    2004-12-01

    Peatlands cover about 21 per cent of the landscape and contain about 80 per cent of the soil carbon stock in western Canada. However, the current rates of carbon accumulation and the environmental controls on ecosystem photosynthesis and respiration in peatland ecosystems is poorly understood. As part of Fluxnet-Canada, we continuously measured net ecosystem carbon dioxide exchange (NEE) using the eddy covariance technique in a treed fen (main site) dominated by stunted black spruce and larch trees during August 2003 through July 2004. Additional NEE measurements were made at two auxiliary sites during intervals in the active growing season (May through September 2004). One auxiliary site was dominated by Sphagnum moss, while the dominant species at other site were Carex and brown mosses. The NEE measurements were used to develop statistical models to assess temporal variation in physiological parameters for ecosystem photosynthesis and respiration. Large seasonal changes occurred in maximum photosynthetic capacity and standardized ecosystem respiration rate at 10 degrees C (R10). The mid-day NEE uptake rate during July averaged 10 μ mol m-2 s-1 at the main site, while lower values of approximately 6 μ mol m-2 s-1 were observed at the two auxiliary sites. No photosynthetic activity was observed during mid-November through mid-March. On an annual basis R10 varied from less than 0.5 μ mol m-2 s-1 in the winter to approximately 3 μ mol m-2 s-1 during August at the main site. During much of the growing season, a distinct hysteresis was observed in the light (photon flux density, PFD) response curves for NEE between morning and afternoon periods. This was caused by large diurnal changes in temperature, which at times resulted in the light compensation point for NEE shifting from a PFD of 100 μ mol m-2 s-1 in the morning to 350 μ mol m-2 s-1 in the afternoon. The main site recorded a net annual gain of 160 g C m-2 yr-1, the result of a difference between gross

  11. Carbon dioxide control in an open system that measures canopy gas exchanges

    USDA-ARS?s Scientific Manuscript database

    Atmospheric carbon dioxide concentration affects both C3 carbon net assimilation as well as crop water use. Methods for measuring whole canopy gas exchange responses under carbon dioxide enrichment are needed for breeding programs aiming to develop crop cultivars resistant to stresses like drought i...

  12. Multiply Controlled Verbal Operants: An Analysis and Extension to the Picture Exchange Communication System

    ERIC Educational Resources Information Center

    Bondy, A.; Tincani, M.; Frost, L.

    2004-01-01

    This paper presents Skinner's (1957) analysis of verbal behavior as a framework for understanding language acquisition in children with autism. We describe Skinner's analysis of pure and impure verbal operants and illustrate how this analysis may be applied to the design of communication training programs. The picture exchange communication system…

  13. Multiply Controlled Verbal Operants: An Analysis and Extension to the Picture Exchange Communication System

    ERIC Educational Resources Information Center

    Bondy, A.; Tincani, M.; Frost, L.

    2004-01-01

    This paper presents Skinner's (1957) analysis of verbal behavior as a framework for understanding language acquisition in children with autism. We describe Skinner's analysis of pure and impure verbal operants and illustrate how this analysis may be applied to the design of communication training programs. The picture exchange communication system…

  14. CONTACT: An Air Force Technical Report on Military Satellite Control Technology

    DTIC Science & Technology

    1993-07-09

    Technolog projections; Future AFSCN topologies; Modeling of the AFSCN; Wide Area Communicatio s Technology evelution; Automating AFSCN Resource...Projections: Methods and Faults Assistant Editor/Desktop Publishing: - Lin Sten Jack Spiker, Scitor Corporation 03 Topologies and Technologies for the...Loral difficult to predict. On dile other hand, technology break- Corporate Technical Journal. He holds two patents and has pub- throughs can happen

  15. Comparative analyses of different variants of standard ground for automatic control systems of technical processes of oil and gas production

    NASA Astrophysics Data System (ADS)

    Gromakov, E. I.; Gazizov, A. T.; Lukin, V. P.; Chimrov, A. V.

    2017-01-01

    The paper analyses efficiency (interference resistance) of standard TT, TN, IT networks in control links of automatic control systems (ACS) of technical processes (TP) of oil and gas production. Electromagnetic compatibility (EMC) is a standard term used to describe the interference in grounding circuits. Improved EMC of ACS TP can significantly reduce risks and costs of malfunction of equipment that could have serious consequences. It has been proved that an IT network is the best type of grounds for protection of ACS TP in real life conditions. It allows reducing the interference down to the level that is stated in standards of oil and gas companies.

  16. Technical Evaluation Report on the Guidance and Control Panel Symposium on Advances in Guidance and Control Systems (35th).

    DTIC Science & Technology

    1983-07-01

    NORT AT[ NTIC TREAY ORANIZTIO DITIBTO Conro SystemsBILITY Th N doCum K hOVs bee opp ove. AGARD-AR-195 NORTH ATLANTIC TREATY ORGANIZATION ADVISORY GROUP...two papers contained obvious marketing material for a company’s product or services which distracted from the technical content. The only major

  17. Current status and future challenges for controlling malaria with the sterile insect technique: technical and social perspectives.

    PubMed

    Oliva, Clelia F; Vreysen, Marc J B; Dupé, Sandrine; Lees, Rosemary S; Gilles, Jeremie R L; Gouagna, Louis-Clement; Chhem, Rethy

    2014-04-01

    The intolerable burden of malaria, when faced with high levels of drug resistance, increasing insecticide resistance and meagre resources at the national level, remains a great public health challenge to governments and the research/control community. Efficient control methods against the vectors of malaria are desperately needed. Control strategies for malaria that integrate the transfer of sterile sperm by released males to wild virgin females with other control tactics are currently being developed, and optimised mass-rearing, irradiation and release techniques are being validated in several field sites. However, the success of this strategy as part of wider pest control or health management programmes strongly depends on gaining public understanding and acceptance. Here we attempt to review what progress has been made and the remaining challenges surrounding the use of the sterile insect technique against malaria from technical and social perspectives. Copyright © 2013 International Atomic Energy Agency 2013. Published by Elsevier B.V. All rights reserved.

  18. Controlled and renewable release of phosphorous in soils from mixtures of phosphate rock and NH4-exchanged clinoptilolite

    USGS Publications Warehouse

    Lai, T.-M.; Eberl, D.D.

    1986-01-01

    A controlled and renewable release fertilization system is proposed that employs NH4 saturated clinoptilolite to aid in the dissolution of phosphate rock (apatite), and thereby to release soluble N, P, and exchangeable Ca for uptake by plants. The system is based on the principle that exchangers can sequester Ca ions released by the dissolution of apatite, thereby leading to further dissolution of the apatite. Experiments show that the quantity of P released by this method is an order of magnitude more than that released by apatite alone. This system offers an alternative technology to the acidulation of phosphate rock, and may circumvent problems associated with highly soluble fertilizers. ?? 1986 Butterworth & Co (Publishers) Ltd.

  19. Water exchange for screening colonoscopy increases adenoma detection rate: a multicenter, double-blinded, randomized controlled trial.

    PubMed

    Cadoni, Sergio; Falt, Přemysl; Rondonotti, Emanuele; Radaelli, Franco; Fojtik, Petr; Gallittu, Paolo; Liggi, Mauro; Amato, Arnaldo; Paggi, Silvia; Smajstrla, Vit; Urban, Ondřej; Erriu, Matteo; Koo, Malcolm; Leung, Felix W

    2017-03-10

    Background and study aims Single-center studies, which were retrospective and/or involved unblinded colonoscopists, have suggested that water exchange, but not water immersion, compared with air insufflation significantly increases the adenoma detection rate (ADR), particularly in the proximal and right colon. Head-to-head comparison of the three techniques with ADR as primary outcome and blinded colonoscopists has not been reported to date. In a randomized controlled trial with blinded colonoscopists, we aimed to evaluate the impact of the three insertion techniques on ADR. Patients and methods A total of 1224 patients aged 50 - 70 years (672 males) and undergoing screening colonoscopy were randomized 1:1:1 to water exchange, water immersion, or air insufflation. Split-dose bowel preparation was adopted to optimize colon cleansing. After the cecum had been reached, a second colonoscopist who was blinded to the insertion technique performed the withdrawal. The primary outcome was overall ADR according to the three insertion techniques (water exchange, water immersion, and air insufflation). Secondary outcomes were other pertinent overall and right colon procedure-related measures. Results Baseline characteristics of the three groups were comparable. Compared with air insufflation, water exchange achieved a significantly higher overall ADR (49.3 %, 95 % confidence interval [CI] 44.3 % - 54.2 % vs. 40.4 % 95 %CI 35.6 % - 45.3 %; P  = 0.03); water exchange showed comparable overall ADR vs. water immersion (43.4 %, 95 %CI 38.5 % - 48.3 %; P  = 0.28). In the right colon, water exchange achieved a higher ADR than air insufflation (24.0 %, 95 %CI 20.0 % - 28.5 % vs. 16.9 %, 95 %CI 13.4 % - 20.9 %; P  = 0.04) and a higher advanced ADR (6.1 %, 95 %CI 4.0 % - 9.0 % vs. 2.5 %, 95 %CI 1.2 % - 4.6 %; P = 0.03). Compared with air insufflation, the mean number of adenomas

  20. Technical Task and Quality Assurance Plan in Support of BNFL Part B: Studies of Ion Exchange Resin Integrity under Flowsheet Extremes: Part II

    SciTech Connect

    Nash, C.A.

    2000-08-23

    This task will address four items related to ion exchange stability: (1) process upset evaluation of resin in contact with 1 molar sodium permanganate at 25 and 40 degrees C, (2) accelerated aging with nitric acid solution used during normal regeneration operations, (3) prolonged contacting of SuperLig 644 resin with 5 molar nitric acid at room temperature, and (4) prolonged contacting of SuperLig 644 resin with deionized water at 60 plus/minus 5 degrees C.

  1. [The experience of carrying out the technical responsibility system in the birth control of Peng County, Sichuan Province].

    PubMed

    Xin, D; Peng, Z L

    1982-11-29

    Following the establishment of the system of fixed responsibility in production in Peng County, Sichuan Province, the County's Family Planning Office and Public Health Bureau in 1980 broadened the system of technical responsibility in birth control by defining tasks and goals. The commune public health office should guide birth control technology, lower the incidence of unplanned pregnancies and the number of abortions. The number of fertile women using IUDs should be over 80%, and its failure rate should be less then 10%; the failure rate of male ligature should be less than 3%. Commune members should give 1 jiao to the public health office for expenses incurred in birth control technology. If all the goals are reached, then there would be economic rewards outside the total public support system. That is, 1 jiao is awarded for each IUD inserted, 2 jiao for male ligatures and 3 jiao for female ligatures. Infractions such as poor attitude, irresponsibility, or delaying surgery are fined from 1-20 yuan. The following situations resulted from having implemented the system of technical responsibilty for birth control: 1) medical personnel had the authority to initiate action concerning birth control technology; 2) the quality of surgery was raised, while the incidence of errors was lowered; 3) the costs of surgery were lowered; and 4) because abortions are not awarded with economic incentives, medical personnel tended to perform more preventive surgery rather than corrective surgery.

  2. Parametric performance studies on fluidized-bed heat exchangers. Task I. Fouling characteristics. Yearly technical progress report, 28 July 1981-31 July 1982

    SciTech Connect

    1982-09-01

    Analyses and experiments are being performed in this program to investigate the heat transfer performance of single and multi-stage shallow fluidized beds for application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. The work, which is an extension of that done previously under contracts EC-77-C-03-1433 and DE-AC03-79-ET11348, consists of three tasks. In Task 1, tests have been conducted to investigate the effects of liquid condensate fouling on fluidized bed heat exchanger performance. Liquid condensates used in these tests were water and glycerol (which is more viscous than water). The tests showed that fluidized bed heat exchanger performance is degraded by condensation within the bed and the degradation is caused by bed particles adhering to the heat exchanger surface, not by particle agglomeration. Liquid condensate did not continuously build up within the bed. After a period of dry-out, heat transfer equal to that obtained prior to condensation was again obtained. 8 figures, 1 table.

  3. Precision Control of the Electron Longitudinal Bunch Shape Using an Emittance-Exchange Beam Line

    DOE PAGES

    Ha, Gwanghui; Cho, Moo -Hyun; Namkung, W.; ...

    2017-03-09

    Here, we report on the experimental generation of relativistic electron bunches with a tunable longitudinal bunch shape. A longitudinal bunch-shaping (LBS) beam line, consisting of a transverse mask followed by a transverse-to-longitudinal emittance exchange (EEX) beam line, is used to tailor the longitudinal bunch shape (or current profile) of the electron bunch. The mask shapes the bunch’s horizontal profile, and the EEX beam line converts it to a corresponding longitudinal profile. The Argonne wakefield accelerator rf photoinjector delivers electron bunches into a LBS beam line to generate a variety of longitudinal bunch shapes. The quality of the longitudinal bunch shapemore » is limited by various perturbations in the exchange process. We develop a simple method, based on the incident slope of the bunch, to significantly suppress the perturbations.« less

  4. Precision control of the electron longitudinal bunch shape using an emittance exchange beamline

    DOE PAGES

    Ha, Gwanghui; Cho, Moo-Hyun; Namkung, W.; ...

    2017-03-09

    We report on the experimental generation of relativistic electron bunches with a tunable longitudinal bunch shape. A longitudinal bunch-shaping (LBS) beam line, consisting of a transverse mask followed by a transverse-to-longitudinal emittance exchange (EEX) beam line, is used to tailor the longitudinal bunch shape (or current profile) of the electron bunch. The mask shapes the bunch’s horizontal profile, and the EEX beam line converts it to a corresponding longitudinal profile. The Argonne wakefield accelerator rf photoinjector delivers electron bunches into a LBS beam line to generate a variety of longitudinal bunch shapes. The quality of the longitudinal bunch shape ismore » limited by various perturbations in the exchange process. We develop a simple method, based on the incident slope of the bunch, to significantly suppress the perturbations.« less

  5. Precision Control of the Electron Longitudinal Bunch Shape Using an Emittance-Exchange Beam Line

    NASA Astrophysics Data System (ADS)

    Ha, G.; Cho, M. H.; Namkung, W.; Power, J. G.; Doran, D. S.; Wisniewski, E. E.; Conde, M.; Gai, W.; Liu, W.; Whiteford, C.; Gao, Q.; Kim, K.-J.; Zholents, A.; Sun, Y.-E.; Jing, C.; Piot, P.

    2017-03-01

    We report on the experimental generation of relativistic electron bunches with a tunable longitudinal bunch shape. A longitudinal bunch-shaping (LBS) beam line, consisting of a transverse mask followed by a transverse-to-longitudinal emittance exchange (EEX) beam line, is used to tailor the longitudinal bunch shape (or current profile) of the electron bunch. The mask shapes the bunch's horizontal profile, and the EEX beam line converts it to a corresponding longitudinal profile. The Argonne wakefield accelerator rf photoinjector delivers electron bunches into a LBS beam line to generate a variety of longitudinal bunch shapes. The quality of the longitudinal bunch shape is limited by various perturbations in the exchange process. We develop a simple method, based on the incident slope of the bunch, to significantly suppress the perturbations.

  6. Environmental turbulent mixing controls on air-water gas exchange in marine and aquatic systems

    NASA Astrophysics Data System (ADS)

    Zappa, Christopher J.; McGillis, Wade R.; Raymond, Peter A.; Edson, James B.; Hintsa, Eric J.; Zemmelink, Hendrik J.; Dacey, John W. H.; Ho, David T.

    2007-05-01

    Air-water gas transfer influences CO2 and other climatically important trace gas fluxes on regional and global scales, yet the magnitude of the transfer is not well known. Widely used models of gas exchange rates are based on empirical relationships linked to wind speed, even though physical processes other than wind are known to play important roles. Here the first field investigations are described supporting a new mechanistic model based on surface water turbulence that predicts gas exchange for a range of aquatic and marine processes. Findings indicate that the gas transfer rate varies linearly with the turbulent dissipation rate to the ${^1}\\!/{_4 power in a range of systems with different types of forcing - in the coastal ocean, in a macro-tidal river estuary, in a large tidal freshwater river, and in a model (i.e., artificial) ocean. These results have important implications for understanding carbon cycling.

  7. Controlling the conductivity and stability of azoles: Proton and hydroxide exchange functionalities

    NASA Astrophysics Data System (ADS)

    Chaloux, Brian Leonard

    For low temperature hydrogen fuel cells to achieve widespread adoption in transport applications, it is necessary to both decrease their cost and improve the range of environmental conditions under which they effectively operate. These problems can be addressed, respectively, by either switching the catalyst from platinum to a less expensive metal, or by reducing the polymer exchange membrane's reliance upon water for proton conduction. This work focuses on understanding the chemistry and physics that limit cation stability in alkaline environments and that enable high proton conductivity in anhydrous polymer exchange membranes. Polystyrenic 1H-azoles (including 1H-tetrazole, 1H-1,2,3-triazole, and 1H-imidazoline) were synthesized to investigate whether pKa and pKb of an amophoteric, proton-conductive group have a systematic effect on anhydrous proton conductivity. It was discovered that the 1H-tetrazole (PS-Tet) exhibited distinct phase separation not seen in its carboxylic acid analog (PSHA) or reported for other 1 H-azole--containing homopolymers in literature. The resulting microstructured polymer, hypothesized to be the result of regions of high and low clustering of azoles, analogous to the multiplet-cluster model of ionomer microstructure, resulted in proton conductivity coupled with simultaneous rubbery behavior of the polymer well above its glass transition (Tg). Phase separation was similarly observed in PS-Tri and PS-ImH2 (the triazole- and imidazoline-containing polymers); soft phases with similar Tgs and hard phases with varying Tgs lend support to this hypothesis of aggregation-driven phase separation. Electrode polarization exhibited in the impedance spectra of PS-Tet and PS-HA was modeled to determine the extent of proton dissociation in undoped 1H-tetrazoles and carboxylic acids. Dry polymers (0% relative humidity) retained ~1% by weight residual water, which was observed to act as the proton acceptor in both cases. Despite doping by residual water

  8. Dynamic analysis and linear control strategies for proton exchange membrane fuel cell using a distributed parameter model

    NASA Astrophysics Data System (ADS)

    Methekar, R. N.; Prasad, V.; Gudi, R. D.

    To satisfy high power density demand in proton exchange membrane fuel cells (PEMFCs), a robust control strategy is essential. A linear ratio control strategy is examined in this work. The manipulated variables are selected using steady-state relative gain array (RGA) analysis to be the inlet molar flow rates of hydrogen and coolant, and the controlled variables are average power density and average solid temperature, respectively. By selecting proper manipulated variables, the PEMFC does not exhibit sign change in gain and hence can be controlled by using a linear controller. Transfer function models obtained from step tests on the distributed parameter PEMFC model are used to design controllers for the multiple input-multiple output (MIMO) system. In addition, a ratio control strategy is proposed and evaluated, where the inlet molar flow rate of oxygen is used as a dependent manipulated variable and changed in a constant ratio with respect to the inlet molar flow rate of hydrogen. Simulation results show that the ratio control strategy provides a faster response than a MIMO control strategy. This ratio control strategy is able to circumvent the problem of oxygen starvation, and the increase in average solid temperature is small as compared to the MIMO control strategy.

  9. Nitroguanidine Wastewater Pollution Control Technology: Phase III. Ion Exchange and Carbon Adsorption Treatment

    DTIC Science & Technology

    1984-03-01

    these :.ons as well as NQ. I/’ I . , I * MATERIALS AND METHODS RESINS AND CARBONS Three ion-exchange materials were studied: clinoptilolite , an...SD are synthetic cross-linked resins provided as moist spherical beads nominally of 50 percent water content. The clinoptilolite was supplied presized...to the nearest mg and maintained at the test temperature for at least 24 hours prior to use. Carbons and clinoptilolite were considered dry as

  10. Two Beam Energy Exchange in Hybrid Liquid Crystal Cells with Photorefractive Field Controlled Boundary Conditions (Postprint)

    DTIC Science & Technology

    2016-09-12

    energy gain when two light beams intersect in a hybrid nematic liquid crystal (LC) cell with photorefractive crystalline substrates. A periodic space...charge field induced by interfering light beams in the photorefractive substrates penetrates into the LC layer and reorients the director. We account...grating and the boundary-driven grating. Each light beam diffracts from the induced gratings leading to an energy exchange between beams. We

  11. An inorganic-organic proton exchange membrane for fuel cells with a controlled nanoscale pore structure.

    PubMed

    Moghaddam, Saeed; Pengwang, Eakkachai; Jiang, Ying-Bing; Garcia, Armando R; Burnett, Daniel J; Brinker, C Jeffrey; Masel, Richard I; Shannon, Mark A

    2010-03-01

    Proton exchange membrane fuel cells have the potential for applications in energy conversion and energy storage, but their development has been impeded by problems with the membrane electrode assembly. Here, we demonstrate that a silicon-based inorganic-organic membrane offers a number of advantages over Nafion--the membrane widely used as a proton exchange membrane in hydrogen fuel cells--including higher proton conductivity, a lack of volumetric size change, and membrane electrode assembly construction capabilities. Key to achieving these advantages is fabricating a silicon membrane with pores with diameters of approximately 5-7 nm, adding a self-assembled molecular monolayer on the pore surface, and then capping the pores with a layer of porous silica. The silica layer reduces the diameter of the pores and ensures their hydration, resulting in a proton conductivity that is two to three orders of magnitude higher than that of Nafion at low humidity. A membrane electrode assembly constructed with this proton exchange membrane delivered an order of magnitude higher power density than that achieved previously with a dry hydrogen feed and an air-breathing cathode.

  12. Histone H2A.Z subunit exchange controls consolidation of recent and remote memory.

    PubMed

    Zovkic, Iva B; Paulukaitis, Brynna S; Day, Jeremy J; Etikala, Deepa M; Sweatt, J David

    2014-11-27

    Memory formation is a multi-stage process that initially requires cellular consolidation in the hippocampus, after which memories are downloaded to the cortex for maintenance, in a process termed systems consolidation. Epigenetic mechanisms regulate both types of consolidation, but histone variant exchange, in which canonical histones are replaced with their variant counterparts, is an entire branch of epigenetics that has received limited attention in the brain and has never, to our knowledge, been studied in relation to cognitive function. Here we show that histone H2A.Z, a variant of histone H2A, is actively exchanged in response to fear conditioning in the hippocampus and the cortex, where it mediates gene expression and restrains the formation of recent and remote memory. Our data provide evidence for H2A.Z involvement in cognitive function and specifically implicate H2A.Z as a negative regulator of hippocampal consolidation and systems consolidation, probably through downstream effects on gene expression. Moreover, alterations in H2A.Z binding at later stages of systems consolidation suggest that this histone has the capacity to mediate stable molecular modifications required for memory retention. Overall, our data introduce histone variant exchange as a novel mechanism contributing to the molecular basis of cognitive function and implicate H2A.Z as a potential therapeutic target for memory disorders.

  13. Optics and materials research for controlled radiant energy transfer in buildings. Final technical report

    SciTech Connect

    Goldner, R.B.

    1996-07-01

    The primary objective of this project was to perform the optics and materials research necessary to identify and solve the technical problems associated with fabricating durable, variable reflectivity electrochromic windows for energy efficient buildings and vehicles. The research performed at the Tufts Electro-Optics Technology Center (EOTC) has identified and solved nearly all the significant problems, as discussed below in this final technical report. There still remains, however, one important problem to be solved--i.e., to better understand the science of deposition processes and thereby develop and optimize one or more production-worthy deposition processes that could be used for the practical production of affordable, variable reflectivity electrochromic windows. Therefore, it is recommended that such studies be carried out with the goals of: (1) determining the probable practical limits of performance; and, very importantly, (2) to develop and optimize deposition processes that could be used for the practical production of affordable electrochromic windows.

  14. OSH technical reference manual

    SciTech Connect

    Not Available

    1993-11-01

    In an evaluation of the Department of Energy (DOE) Occupational Safety and Health programs for government-owned contractor-operated (GOCO) activities, the Department of Labor`s Occupational Safety and Health Administration (OSHA) recommended a technical information exchange program. The intent was to share written safety and health programs, plans, training manuals, and materials within the entire DOE community. The OSH Technical Reference (OTR) helps support the secretary`s response to the OSHA finding by providing a one-stop resource and referral for technical information that relates to safe operations and practice. It also serves as a technical information exchange tool to reference DOE-wide materials pertinent to specific safety topics and, with some modification, as a training aid. The OTR bridges the gap between general safety documents and very specific requirements documents. It is tailored to the DOE community and incorporates DOE field experience.

  15. Cooperation between bound waters and hydroxyls in controlling isotope-exchange rates

    NASA Astrophysics Data System (ADS)

    Panasci, Adele F.; McAlpin, J. Gregory; Ohlin, C. André; Christensen, Shauna; Fettinger, James C.; Britt, R. David; Rustad, James R.; Casey, William H.

    2012-02-01

    Mineral oxides differ from aqueous ions in that the bound water molecules are usually attached to different metal centers, or vicinal, and thus separated from one another. In contrast, for most monomeric ions used to establish kinetic reactivity trends, such as octahedral aquo ions (e.g., Al(H 2O) 63+), the bound waters are closely packed, or geminal. Because of this structural difference, the existing literature about ligand substitution in monomer ions may be a poor guide to the reactions of geochemical interest. To understand how coordination of the reactive functional groups might affect the rates of simple water-exchange reactions, we synthesized two structurally similar Rh(III) complexes, [Rh(phen) 2(H 2O) 2] 3+ [ 1] and [Rh(phen) 2(H 2O)Cl] 2+ [ 2] where (phen) = 1,10-phenanthroline. Complex [ 1] has two adjacent, geminal, bound waters in the inner-coordination sphere and [ 2] has a single bound water adjacent to a bound chloride ion. We employed Rh(III) as a trivalent metal rather than a more geochemically relevant metal like Fe(III) or Al(III) to slow the rate of reaction, which makes possible measurement of the rates of isotopic substitution by simple mass spectrometry. We prepared isotopically pure versions of the molecules, dissolved them into isotopically dissimilar water, and measured the rates of exchange from the extents of 18O and 16O exchange at the bound waters. The pH dependency of rates differ enormously between the two complexes. Pseudo-first-order rate coefficients at 298 K for water exchanges from the fully protonated molecules are close: k0298 = 5 × 10 -8(±0.5 × 10 -8) s -1 for [ 1] and k0298 = 2.5 × 10 -9(±1 × 10 -9) for [ 2]. Enthalpy and entropy activation parameters (Δ H‡ and Δ S‡) were measured to be 119(±3) kJ mol -1, and 14(±1) J mol -1 K -1, respectively for [ 1]. The corresponding parameters for the mono-aquo complex, [ 2], are 132(±3) kJ mol -1 and 41.5(±2) J mol -1 K -1. Rates increase by many orders of magnitude

  16. Assessment of the possibility of establishing material cycling in an experimental model of the bio-technical life support system with plant and human wastes included in mass exchange

    NASA Astrophysics Data System (ADS)

    Tikhomirov, A. A.; Ushakova, S. A.; Velichko, V. V.; Tikhomirova, N. A.; Kudenko, Yu. A.; Gribovskaya, I. V.; Gros, J.-B.; Lasseur, Ch.

    2011-05-01

    A pilot model of a bio-technical life support system (BTLSS) including human and plant wastes has been developed at the Institute of Biophysics SB RAS (Krasnoyarsk, Russia). This paper describes the structure of the photosynthesizing unit of the system, which includes wheat, chufa and vegetables. The study substantiates the simultaneous use of neutral and biological substrates for cultivating plants. A novel physicochemical method for the involvement of human wastes in the cycling has been employed, which enables the use of recycled products as nutrients for plants. Inedible plant biomass was subjected to biological combustion in the soil-like substrate (SLS) and was thus involved in the system mass exchange; NaCl contained in native urine was returned to the human through the consumption of Salicornia europaea, an edible salt-concentrating plant. Mass transfer processes in the studied BLSS have been examined for different chemical components.

  17. Functionalized Mesoporous Silica via an Aminosilane Surfactant Ion Exchange Reaction: Controlled Scaffold Design and Nitric Oxide Release

    PubMed Central

    2015-01-01

    Nitric oxide-releasing mesoporous silica nanoparticles (MSNs) were prepared using an aminosilane-template surfactant ion exchange reaction. Initially, bare silica particles were synthesized under basic conditions in the presence of cetyltrimethylammonium bromide (CTAB). These particles were functionalized with nitric oxide (NO) donor precursors (i.e., secondary amines) via the addition of aminosilane directly to the particle sol and a commensurate ion exchange reaction between the cationic aminosilanes and CTAB. N-Diazeniumdiolate NO donors were formed at the secondary amines to yield NO-releasing MSNs. Tuning of the ion exchange-based MSN modification approach allowed for the preparation of monodisperse particles ranging from 30 to 1100 nm. Regardless of size, the MSNs stored appreciable levels of NO (0.4–1.5 μmol mg–1) with tunable NO release durations (1–33 h) dependent on the aminosilane modification. Independent control of NO release properties and particle size was achieved, demonstrating the flexibility of this novel MSN synthesis over conventional co-condensation and surface grafting strategies. PMID:26717238

  18. Perfect spin filtering controlled by an electric field in a bilayer graphene junction: Effect of layer-dependent exchange energy

    NASA Astrophysics Data System (ADS)

    Kitakorn, Jatiyanon; I-Ming, Tang; Bumned, Soodchomshom

    2016-07-01

    Magneto transport of carriers with a spin-dependent gap in a ferromagnetic-gated bilayer of graphene is investigated. We focus on the effect of an energy gap induced by the mismatch of the exchange fields in the top and bottom layers of an AB-stacked graphene bilayer. The interplay of the electric and exchange fields causes the electron to acquire a spin-dependent energy gap. We find that, only in the case of the anti-parallel configuration, the effect of a magnetic-induced gap will give rise to perfect spin filtering controlled by the electric field. The resolution of the spin filter may be enhanced by varying the bias voltage. Perfect switching of the spin polarization from + 100% to -100% by reversing the direction of electric field is predicted. Giant magnetoresistance is predicted to be easily realized when the applied electric field is smaller than the magnetic energy gap. It should be pointed out that the perfect spin filter is due to the layer-dependent exchange energy. This work points to the potential application of bilayer graphene in spintronics. Project supported by the Kasetsart University Research and Development Institute (KURDI) and Thailand Research Fund (TRF) (Grant No. TRG5780274).

  19. Functionalized Mesoporous Silica via an Aminosilane Surfactant Ion Exchange Reaction: Controlled Scaffold Design and Nitric Oxide Release.

    PubMed

    Soto, Robert J; Yang, Lei; Schoenfisch, Mark H

    2016-01-27

    Nitric oxide-releasing mesoporous silica nanoparticles (MSNs) were prepared using an aminosilane-template surfactant ion exchange reaction. Initially, bare silica particles were synthesized under basic conditions in the presence of cetyltrimethylammonium bromide (CTAB). These particles were functionalized with nitric oxide (NO) donor precursors (i.e., secondary amines) via the addition of aminosilane directly to the particle sol and a commensurate ion exchange reaction between the cationic aminosilanes and CTAB. N-Diazeniumdiolate NO donors were formed at the secondary amines to yield NO-releasing MSNs. Tuning of the ion exchange-based MSN modification approach allowed for the preparation of monodisperse particles ranging from 30 to 1100 nm. Regardless of size, the MSNs stored appreciable levels of NO (0.4-1.5 μmol mg(-1)) with tunable NO release durations (1-33 h) dependent on the aminosilane modification. Independent control of NO release properties and particle size was achieved, demonstrating the flexibility of this novel MSN synthesis over conventional co-condensation and surface grafting strategies.

  20. Palmitoylation of the Na/Ca exchanger cytoplasmic loop controls its inactivation and internalization during stress signaling

    PubMed Central

    Reilly, Louise; Howie, Jacqueline; Wypijewski, Krzysztof; Ashford, Michael L. J.; Hilgemann, Donald W.; Fuller, William

    2015-01-01

    The electrogenic Na/Ca exchanger (NCX) mediates bidirectional Ca movements that are highly sensitive to changes of Na gradients in many cells. NCX1 is implicated in the pathogenesis of heart failure and a number of cardiac arrhythmias. We measured NCX1 palmitoylation using resin-assisted capture, the subcellular location of yellow fluorescent protein–NCX1 fusion proteins, and NCX1 currents using whole-cell voltage clamping. Rat NCX1 is substantially palmitoylated in all tissues examined. Cysteine 739 in the NCX1 large intracellular loop is necessary and sufficient for NCX1 palmitoylation. Palmitoylation of NCX1 occurs in the Golgi and anchors the NCX1 large regulatory intracellular loop to membranes. Surprisingly, palmitoylation does not influence trafficking or localization of NCX1 to surface membranes, nor does it strongly affect the normal forward or reverse transport modes of NCX1. However, exchangers that cannot be palmitoylated do not inactivate normally (leading to substantial activity in conditions when wild-type exchangers are inactive) and do not promote cargo-dependent endocytosis that internalizes 50% of the cell surface following strong G-protein activation or large Ca transients. The palmitoylated cysteine in NCX1 is found in all vertebrate and some invertebrate NCX homologs. Thus, NCX palmitoylation ubiquitously modulates Ca homeostasis and membrane domain function in cells that express NCX proteins.—Reilly, L., Howie, J., Wypijewski, K., Ashford, M. L. J., Hilgemann, D. W., Fuller, W. Palmitoylation of the Na/Ca exchanger cytoplasmic loop controls its inactivation and internalization during stress signaling. PMID:26174834

  1. Understanding Groundwater and Surface Water Exchange Processes Along a Controlled Stream Using Thermal Remote Sensing and In-Situ Measurements

    NASA Astrophysics Data System (ADS)

    Varli, D.; Yilmaz, K. K.

    2016-12-01

    Effective management of water resources requires understanding and quantification of interaction between groundwater and surface water bodies. Moreover, the exchange processes have recently received increasing attention due to important influences on biogeochemical and ecological status of watersheds. In this study we investigated the exchange processes between surface water and groundwater along Kirmir stream - a controlled stream nearby Kizilcahamam, Ankara, Turkey. At the first stage, potential stream reaches where the exchange processes could occur were pinpointed using geological and geomorphological information. Then, thermal remote sensing was utilized to further narrow down the potential locations in which interaction could occur at a smaller scale. Nested piezometers were installed at identified locations to observe the variations in vertical hydraulic gradient over time. Differential discharge measurements were performed to understand the gains and losses along the stream reach. Streambed temperature measurements were taken at two different depths for a period of time using temperature loggers to calculate the vertical fluid fluxes through the streambed at various locations. Basic water quality field parameters (temperature, electrical conductivity, total dissolved solid amount, dissolved oxygen, pH and oxidation - reduction potential) were measured along the stream reach, from surface water and the piezometers as wells as from the nearby springs and wells. Chloride mass balance was performed to find the contribution of groundwater and chloride concentrations were associated with the geology of the area. This hierarchical, multi-scale methodology provided an efficient and effective way to determine the locations and the direction of groundwater and surface water exchange processes within the study area.

  2. Charge exchange system

    DOEpatents

    Anderson, Oscar A.

    1978-01-01

    An improved charge exchange system for substantially reducing pumping requirements of excess gas in a controlled thermonuclear reactor high energy neutral beam injector. The charge exchange system utilizes a jet-type blanket which acts simultaneously as the charge exchange medium and as a shield for reflecting excess gas.

  3. Controls for multi-scale temporal variation in ecosystem methane exchange during the growing season of a permanently inundated fen

    NASA Astrophysics Data System (ADS)

    Koebsch, Franziska; Jurasinski, Gerald; Koch, Marian; Hofmann, Joachim; Glatzel, Stephan

    2014-05-01

    Temperature and phenology trigger seasonal variation of CH4 emissions in many ecosystems. However, ecosystem CH4 exchange varies also considerably on smaller temporal scales such as days or weeks. Indeed, we are aware of many processes that control CH4 emissions on the local soil-plant-atmosphere continuum, but their interaction on ecosystem level is not well understood yet. We used a quasi-continuous Eddy Covariance CH4 flux time series and wavelet analysis to describe the temporal variation of ecosystem CH4 exchange within the growing season of a permanently inundated temperate fen. Moreover, we assigned time scale-specific controls and investigated whether their impact changes during the course of the growing season. Water/soil temperature correlated with ecosystem CH4 exchange at time scales of 6-11 and 22 days which exceeds the time scales that are typically associated with the passage of weather fronts. The low response time might be due to the high heat capacity of the water column. On a daily scale, shear-induced turbulence (presented by friction velocity) and plant activity (presented by canopy photosynthesis) caused a diurnal variation of ecosystem CH4 exchange with peak time around noon. However, this pattern was apparent only at the beginning of the growing season (April/May). In the following, convective mixing of the water column (presented by the water temperature gradient) gradually gained importance and caused high night-time CH4 emissions, thereby levelling off the diurnal CH4 emission pattern. Our study highlights the need for multi-scale approaches that consider the non-stationarity of the underlying processes to adequately describe the complexity of ecosystem CH4 exchange. Moreover, we show that CH4 release processes such as convective mixing of the water column which has been mainly known from aquatic ecosystems until recently (Godwin et al. 2013), might be also of importance in shallowly flooded terrestrial ecosystems. Citation: Godwin CM, Mc

  4. Energy-Exchange Project

    SciTech Connect

    Not Available

    1982-04-01

    The purpose of the study was to determine what energy savings can be achieved by coordinating the resources and requirements of two facilities, the 26th Ward Water Pollution Control Plant (WPCP) and a housing development named Starrett City with its own total energy system. It was determined that three energy exchange options were economically and technically feasible. These include: the transfer of digester gas produced at the 26th Ward to the boilers at the Starrett City's total energy plant (TEP); the transfer of hot water heated at the TEP to the 26th Ward for space and process heating; and the transfer of coal effluent waste water from the 26th Ward to the condenser cooling systems at the TEP. Technical information is presented to support the findings. The report addresses those tasks of the statement of work dedicated to data acquisition, analysis, and energy conservation strategies internal to the Starrett City TEP and the community it supplies as well as to the 26th Ward WPCP. (MCW)

  5. Controlling factors of biosphere-atmosphere ammonia exchange at a semi-natural peatland site

    NASA Astrophysics Data System (ADS)

    Brummer, C.; Richter, U.; Smith, J. J.; Delorme, J. P.; Kutsch, W. L.

    2014-12-01

    Recent advancements in laser spectrometry offer new opportunities to investigate net biosphere-atmosphere exchange of ammonia. During a three month field campaign from February to May 2014, we tested the performance of a quantum cascade laser within an eddy-covariance setup. The laser was operated at a semi-natural peatland site that is surrounded by highly fertilized agricultural land and intensive livestock production (~1 km distance). Ammonia concentrations were highly variable between 2 and almost 100 ppb with an average value of 15 ppb. Different concentration patterns could be identified. The variability was closely linked to the timing of management practices and the prevailing local climate, particularly wind direction, temperature and surface wetness with the latter indicating higher non-stomatal uptake under wet conditions leading to decreased concentrations. Average ammonia fluxes were around -15 ng N m-2 s-1 at the beginning of the campaign in February and shifted towards a neutral average exchange regime of -1 to 0 ng N m-2 s-1 in April and May. Intriguingly, during the time of decreasing ammonia uptake, concentrations were considerably rising, which clearly indicated N saturation in the predominant vegetation such as bog heather, purple moor-grass, and cotton grass. The cumulative net uptake for the period of investigation was ~300 g N ha-1. This stresses the importance of a thorough method inter-comparison, e.g. with denuder systems in combination with dry deposition modeling. As previous results from the latter methods showed an annual uptake of ~9 kg N ha-1 for the same site, the implementation of adequate ammonia compensation point parameterizations become crucial in surface-atmosphere exchange schemes for bog vegetation. Through their high temporal resolution, robustness and continuous measurement mode, quantum cascade lasers will help assessing the effects of atmospheric N loads to vulnerable N-limited ecosystems such as peatlands.

  6. Controlled Under Pressure: Understanding Spin Orbit Coupling and Exchange Anisotropy in Organic Magnets

    NASA Astrophysics Data System (ADS)

    Hill, Stephen

    2015-03-01

    The application of high pressure in the study of molecule-based materials has gained considerable interest, in part due to their high compressibilities, but also because the relevant electronic/magnetic degrees of freedom are often very sensitive to pressure. For example, small changes in the coordination environment around a magnetic transition metal ion can produce quite dramatic variations in both the on-site spin-orbit anisotropy as well as the exchange interactions between such ions when assembled into clusters or 3D networks. This has spurred the development of sophisticated spectroscopic tools that can be integrated with high-pressure instrumentation. The study of magnetic structure/property relations requires not only precise crystallographic data, but also detailed spectroscopic information concerning the unpaired electrons that give rise to the magnetic properties. This invited talk will begin with a brief description of the development and application of methods enabling EPR studies of oriented single-crystal samples subjected to hydrostatic pressures of up to 3.5 GPa. After an introductory example, the remainder of the talk will focus on a family of heavy atom organic radical ferromagnets (containing S and Se heteroatoms) that hold records for both the highest transition temperature and coercivity (for organic magnets). The latter is the result of an unexpectedly high magnetic anisotropy, attributable to spin-orbit-mediated exchange (hopping) processes., Ferromagnetic resonance (FMR) measurements reveal a continuous increase in the magnetic anisotropy with increasing pressure in the all Se compound, in excellent agreement with ab initio calculations based on the known pressure-dependence of its structure. The large value of anisotropic exchange terms in this heavy atom organic ferromagnet emphasizes the important role of spin-orbit coupling in a wide range of organics where this effect is usually considered to be small. This work was supported by the

  7. Vibration Control of Space Structures VCOSS B: Momentum Exchange and Truss Dampening.

    DTIC Science & Technology

    1983-07-01

    VCOSS B: M-CTMNtIIM(CHANGE AND TRUSS DAMPEN~ING FINIAL 8/81-7/83 6. PERFORMING ORG. REPORT NUMBER 7. AUTOR(&)8. CONTRACT OR GRANT NUMBER(s) R...of the Contract No. F33615-81-C-3235. This report covers the period froan 1 August 1981 througrh 1 July 1983. The technical monitor was Jerrrie...and their description; are listed in Tablo II. As expected, all the isolator modes now have mucl lower frequencies than the solar paiel modes. However

  8. Heat exchange from the toucan bill reveals a controllable vascular thermal radiator.

    PubMed

    Tattersall, Glenn J; Andrade, Denis V; Abe, Augusto S

    2009-07-24

    The toco toucan (Ramphastos toco), the largest member of the toucan family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, from serving as a sexual ornament to being a refined adaptation for feeding. However, it is also a significant surface area for heat exchange. Here we show the remarkable capacity of the toco toucan to regulate heat distribution by modifying blood flow, using the bill as a transient thermal radiator. Our results indicate that the toucan's bill is, relative to its size, one of the largest thermal windows in the animal kingdom, rivaling elephants' ears in its ability to radiate body heat.

  9. A Methodology for Evaluating Technical Performance Parameter Design Margins to Control Earth and Space Science Instrument Cost

    NASA Astrophysics Data System (ADS)

    Jones-Selden, Felicia L.

    Costs of aerospace missions have increased over the last twenty years, placing the future of the space program in jeopardy. A potential source for such growth can be attributed to the complex multidisciplinary and challenging nature of earth and space science instrument development. Design margins are additional resources carried in technical performance parameters to mitigate uncertainties throughout the product lifecycle. Margins are traditionally derived and allocated based upon historical experience intrinsic to organizations, as opposed to quantitative methods, jeopardizing the development of low-cost space-based instruments. This dissertation utilizes a methodology to evaluate the interrelationships between pre-launch and actual launch margins for the key technical performance parameters of mass, power, and data-rate to identify the extent to which excessive or insufficient margins are used in the design of space-based instruments in an effort to control instrument cost growth. The research examined 62 space-based instruments from the National Aeronautics and Space Administration, Federally Funded Research and Development Centers, and universities. Statistical analysis consisting of paired t-tests and multiple linear regression were utilized to determine the degree to which space-based instruments are over or under designed by the use of excessive or insufficient design margins and to determine the effect of design margins for the technical performance parameters of mass, power, and data-rate on the percentage instrument cost growth from the preliminary design phase to launch. Findings confirm, that in the implementation of space-based instruments, design margins are allocated to technical performance parameters above suggested government/industry standards, impacting the development of low-cost space-based instruments. The findings provide senior leadership, systems engineers, project managers, and resource managers with the ability to determine where

  10. Technically accurate intracavitary insertions improve pelvic control and survival among patients with locally advanced carcinoma of the uterine cervix.

    PubMed

    Corn, B W; Hanlon, A L; Pajak, T F; Owen, J; Hanks, G E

    1994-06-01

    The purpose of this study was to document whether the technical qualities of a brachytherapy application impacts on the outcome of patients with locally advanced cervix cancer treated by definitive irradiation. A previous report from the patterns of care study demonstrated the importance of brachytherapy in the treatment of locally advanced cervix cancer. Locally advanced disease was defined as FIGO stages Ib (if tumor diameter was < or = 4 cm), IIb (if disease was bilateral or involved the lateral aspect of either parametrium), and III. Localization films from 128 patients with locally advanced squamous cell carcinoma of the cervix were reviewed by a radiation physicist and a radiation oncologist with expertise in gynecologic radiotherapy. All patients received external beam irradiation followed by one brachytherapy application (median point A dose = 8040 cGy; range, 4083-10,020 cGy). Brachytherapy parameters assessed were (a) the distance between the right colpostat source and the distal tandem source, (b) the distance between the left colpostat source and the distal tandem source, and (c) the symmetry of colpostat placement. Implants were scored as "ideal" (n = 8) when all three parameters were deemed satisfactory, "unacceptable" (n = 17) when none of the parameters was deemed satisfactory, and "adequate" (n = 41) in all other cases. Significantly improved 5-year local control was seen when comparing ideal and adequate placements to unacceptable placements (68% vs 34%, P = 0.02). A strong trend toward improved 5-year survival was also noted among the group with ideal and adequate implants as opposed to unacceptable implants (60% vs 40%). Multivariate analysis showed that the technical adequacy of the brachytherapy implant was the most important prognostic discriminant of local control. In conclusion, these analyses demonstrate the direct influence of competent technical implant performance on tumor control and even survival. While only a small fraction of

  11. Use of radon and cosmogenic radionuclides as indicators of exchange between troposphere and stratosphere. Final technical report, 1 January 1984-31 October 1987

    SciTech Connect

    Kritz, M.A.

    1994-08-01

    This research grant covered participation in the operational phase of NASA's Stratosphere-Troposphere Exchange Project (STEP), a multi-agency airborne science program conducted aboard NASA U-2 and ER-2 high altitude research aircraft. The primary goals of STEP were to investigate the mechanisms of irreversible movement of mass, trace gases, and aerosols from the troposphere into the stratosphere, and to explain the observed dryness of the stratosphere. Three flight experiments were conducted to address these questions: two extratropical experiments, in 1984 and 1986, and a tropical experiment, in 1987. The cosmogenic radionuclides Be-7 and P-32, produced in the stratosphere by cosmic rays, and Rn-222 (radon), emitted from continental soils, were well-suited as tracers of intra-stratospheric air mass movements, and to follow episodes of troposphere to stratosphere exchange. Measurements of Be-7 and P-32 were made in all three STEP experiments. Measurements of radon were made in the tropical experiment only. The equipment worked well, and produced a valuable data set in support of the STEP objectives, as indicated by the 'quick-look' results outlined.

  12. Chemistry, manufacturing and control (CMC) and clinical trial technical support for influenza vaccine manufacturers.

    PubMed

    Wahid, Rahnuma; Holt, Renee; Hjorth, Richard; Berlanda Scorza, Francesco

    2016-10-26

    With the support of the Biomedical Advanced Research and Development Authority (BARDA) of the US Department of Health and Human Services, PATH has contributed to the World Health Organization's (WHO's) Global Action Plan for Influenza Vaccines (GAP) by providing technical and clinical assistance to several developing country vaccine manufacturers (DCVMs). GAP builds regionally based independent and sustainable influenza vaccine production capacity to mitigate the overall global shortage of influenza vaccines. The program also ensures adequate influenza vaccine manufacturing capacity in the event of an influenza pandemic. Since 2009, PATH has worked closely with two DCVMs in Vietnam: the Institute of Vaccines and Medical Biologicals (IVAC) and VABIOTECH. Beginning in 2013, PATH also began working with Torlak Institute in Serbia; Instituto Butantan in Brazil; Serum Institute of India Private Ltd. in India; and Changchun BCHT Biotechnology Co. (BCHT) in China. The DCVMs supported under the GAP program all had existing influenza vaccine manufacturing capability and required technical support from PATH to improve vaccine yield, process efficiency, and product formulation. PATH has provided customized technical support for the manufacturing process to each DCVM based on their respective requirements. Additionally, PATH, working with BARDA and WHO, supported several DCVMs in the clinical development of influenza vaccine candidates progressing toward national licensure or WHO prequalification. As a result of the activities outlined in this review, several companies were able to make excellent progress in developing state-of-the-art manufacturing processes and completing early phase clinical trials. Licensure trials are currently ongoing or planned for several DCVMs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Owner controlled data exchange in nutrigenomic collaborations: the NuGO information network.

    PubMed

    Harttig, Ulrich; Travis, Anthony J; Rocca-Serra, Philippe; Renkema, Marten; van Ommen, Ben; Boeing, Heiner

    2009-06-01

    New 'omics' technologies are changing nutritional sciences research. They enable to tackle increasingly complex questions but also increase the need for collaboration between research groups. An important challenge for successful collaboration is the management and structured exchange of information that accompanies data-intense technologies. NuGO, the European Nutrigenomics Organization, the major collaborating network in molecular nutritional sciences, is supporting the application of modern information technologies in this area. We have developed and implemented a concept for data management and computing infrastructure that supports collaboration between nutrigenomics researchers. The system fills the gap between "private" storing with occasional file sharing by email and the use of centralized databases. It provides flexible tools to share data, also during experiments, while preserving ownership. The NuGO Information Network is a decentral, distributed system for data exchange based on standard web technology. Secure access to data, maintained by the individual researcher, is enabled by web services based on the the BioMoby framework. A central directory provides information about available web services. The flexibility of the infrastructure allows a wide variety of services for data processing and integration by combining several web services, including public services. Therefore, this integrated information system is suited for other research collaborations.

  14. On the processes controlling shelf-basin exchange and outer shelf dynamics in the Bering Sea

    NASA Astrophysics Data System (ADS)

    Clement Kinney, J.; Maslowski, W.; Okkonen, S.

    2009-08-01

    We use a 9-km pan-Arctic ice-ocean model to better understand the circulation and exchanges in the Bering Sea, particularly near the shelf break. This region has, historically, been undersampled for physical, chemical, and biological properties. Very little is known about how water from the deep basin reaches the large, shallow Bering Sea shelf. To address this, we examine here the relationship between the Bering Slope Current and exchange across the shelf break and resulting mass and property fluxes onto the shelf. This understanding is critical to gain insight into the effects that the Bering Sea has on the Arctic Ocean, especially in regard to recent indications of a warming climate in this region. The Bering Sea shelf break region is characterized by the northwestward-flowing Bering Slope Current. Previously, it was thought that once this current neared the Siberian coast, a portion of it made a sharp turn northward and encircled the Gulf of Anadyr in an anticyclonic fashion. Our model results indicate a significantly different circulation scheme whereby water from the deep basin is periodically moved northward onto the shelf by mesoscale processes along the shelf break. Canyons along the shelf break appear to be more prone to eddy activity and, therefore, are associated with higher rates of on-shelf transport. The horizontal resolution configured in this model now allows for the representation of eddies with diameters greater than 36 km; however, we are unable to resolve the smaller eddies.

  15. Controlling Disorder and Superconductivity in Titanium Oxynitride Nanoribbons with Anion Exchange.

    PubMed

    Sluban, Melita; Umek, Polona; Jagličić, Zvonko; Buh, Jože; Šmitek, Petra; Mrzel, Aleš; Bittencourt, Carla; Guttmann, Peter; Delville, Marie-Helene; Mihailović, Dragan; Arčon, Denis

    2015-10-27

    In recent years, conversion chemical reactions, which are driven by ion diffusion, emerged as an important concept for formation of nanoparticles. Here we demonstrate that the slow anion diffusion in anion exchange reactions can be efficiently used to tune the disorder strength and the related electronic properties of nanoparticles. This paradigm is applied to high-temperature formation of titanium oxynitride nanoribbons, Ti(O,N), transformed from hydrogen titanate nanoribbons in an ammonia atmosphere. The nitrogen content, which determines the chemical disorder through random O/N occupancy and ion vacancies in the Ti(O,N) composition, increases with the reaction time. The presence of disorder has paramount effects on resistivity of Ti(O,N) nanoribbons. Atypically for metals, the resistivity increases with decreasing temperature due to the weak localization effects. From this state, superconductivity develops below considerably or completely suppressed critical temperatures, depending on the disorder strength. Our results thus establish the remarkable versatility of anion exchange for tuning of the electronic properties of Ti(O,N) nanoribbons and suggest that similar strategies may be applied to a vast number of nanostructures.

  16. Telerobotic control of a mobile coordinated robotic server. M.S. Thesis Annual Technical Report

    NASA Technical Reports Server (NTRS)

    Lee, Gordon

    1993-01-01

    The annual report on telerobotic control of a mobile coordinated robotic server is presented. The goal of this effort is to develop advanced control methods for flexible space manipulator systems. As such, an adaptive fuzzy logic controller was developed in which model structure as well as parameter constraints are not required for compensation. The work builds upon previous work on fuzzy logic controllers. Fuzzy logic controllers have been growing in importance in the field of automatic feedback control. Hardware controllers using fuzzy logic have become available as an alternative to the traditional PID controllers. Software has also been introduced to aid in the development of fuzzy logic rule-bases. The advantages of using fuzzy logic controllers include the ability to merge the experience and intuition of expert operators into the rule-base and that a model of the system is not required to construct the controller. A drawback of the classical fuzzy logic controller, however, is the many parameters needed to be turned off-line prior to application in the closed-loop. In this report, an adaptive fuzzy logic controller is developed requiring no system model or model structure. The rule-base is defined to approximate a state-feedback controller while a second fuzzy logic algorithm varies, on-line, parameters of the defining controller. Results indicate the approach is viable for on-line adaptive control of systems when the model is too complex or uncertain for application of other more classical control techniques.

  17. Quality Control. Supervising. Technical Aspects of Supervision. The Choice Series #35. A Self Learning Opportunity.

    ERIC Educational Resources Information Center

    Lawson, Fred

    This student guide is intended to assist persons employed as supervisors in improving their knowledge and skills in the area of quality control. Discussed in the first three sections are the following topics: quality and control (quality, measuring and achieving quality, controlling resources, and quality consciousness); quality control and…

  18. Aquatic Plant Control Program. Technical Report 7. Aquatic-Use Patterns for 2,4-D Dimethylamine and Integrated Control.

    DTIC Science & Technology

    Aquatic weed control, D2-4 herbicide, Acetic acid/2-4 dichlorophenoxy, Chlorine aromatic compounds, Alligatorweed, Water hyacinth, Eichhornia crassipes , Dimethylamine, Water pollution control, Pesticide residues

  19. Changing controls on oceanic radiocarbon: New insights on shallow-to-deep ocean exchange and anthropogenic CO2 uptake

    NASA Astrophysics Data System (ADS)

    Graven, H. D.; Gruber, N.; Key, R.; Khatiwala, S.; Giraud, X.

    2012-10-01

    The injection of radiocarbon (14C) into the atmosphere by nuclear weapons testing in the 1950s and 1960s has provided a powerful tracer to investigate ocean physical and chemical processes. While the oceanic uptake of bomb-derived 14C was primarily controlled by air-sea exchange in the early decades after the bomb spike, we demonstrate that changes in oceanic 14C are now primarily controlled by shallow-to-deep ocean exchange, i.e., the same mechanism that governs anthropogenic CO2 uptake. This is a result of accumulated bomb 14C uptake that has rapidly decreased the air-sea gradient of 14C/C (Δ14C) and shifted the main reservoir of bomb 14C from the atmosphere to the upper ocean. The air-sea Δ14C gradient, reduced further by fossil fuel dilution, is now weaker than before weapons testing in most regions. Oceanic 14C, and particularly its temporal change, can now be used to study the oceanic uptake of anthropogenic CO2. We examine observed changes in oceanic Δ14C between the WOCE/SAVE (1988-1995) and the CLIVAR (2001-2007) eras and simulations with two ocean general circulation models, the Community Climate System Model (CCSM) and the Estimating the Circulation and Climate of the Ocean Model (ECCO). Observed oceanic Δ14C and its changes between the 1980s-90s and 2000s indicate that shallow-to-deep exchange is too efficient in ECCO and too sluggish in CCSM. These findings suggest that mean global oceanic uptake of anthropogenic CO2 between 1990 and 2007 is bounded by the ECCO-based estimate of 2.3 Pg C yr-1 and the CCSM-based estimate of 1.7 Pg C yr-1.

  20. Continued benefits of a technical assistance web site to local tobacco control coalitions during a state budget shortfall.

    PubMed

    Buller, David B; Young, Walter F; Bettinghaus, Erwin P; Borland, Ron; Walther, Joseph B; Helme, Donald; Andersen, Peter A; Cutter, Gary R; Maloy, Julie A

    2011-01-01

    A state budget shortfall defunded 10 local tobacco coalitions during a randomized trial but defunded coalitions continued to have access to 2 technical assistance Web sites. To test the ability of Web-based technology to provide technical assistance to local tobacco control coalitions. Randomized 2-group trial with local tobacco control coalitions as the unit of randomization. Local communities (ie, counties) within the State of Colorado. Leaders and members in 34 local tobacco control coalitions funded by the state health department in Colorado. Two technical assistance Web sites: A Basic Web site with text-based information and a multimedia Enhanced Web site containing learning modules, resources, and communication features. Use of the Web sites in minutes, pages, and session and evaluations of coalition functioning on coalition development, conflict resolution, leadership satisfaction, decision-making satisfaction, shared mission, personal involvement, and organization involvement in survey of leaders and members. Coalitions that were defunded but had access to the multimedia Enhanced Web site during the Fully Funded period and after defunding continued to use it (treatment group × funding status × period, F(3,714) = 3.18, P = .0234). Coalitions with access to the Basic Web site had low Web site use throughout and use by defunded coalitions was nearly zero when funding ceased. Members in defunded Basic Web site coalitions reported that their coalitions functioned worse than defunded Enhanced Web site coalitions (coalition development: group × status, F(1,360) = 4.81, P = .029; conflict resolution: group × status, F(1,306) = 5.69, P = .018; leadership satisfaction: group × status, F(1,342) = 5.69, P = .023). The Enhanced Web site may have had a protective effect on defunded coalitions. Defunded coalitions may have increased their capacity by using the Enhanced Web site when fully funded or by continuing to use the available online resources after defunding

  1. A contrast between children and adolescents with excellent and poor control: the T1D Exchange clinic registry experience.

    PubMed

    Campbell, Meredith S; Schatz, Desmond A; Chen, Vincent; Wong, Jenise C; Steck, Andrea; Tamborlane, William V; Smith, Jennifer; Beck, Roy W; Cengiz, Eda; Laffel, Lori M; Miller, Kellee M; Haller, Michael J

    2014-03-01

    Optimizing glycemic control in pediatric type 1 diabetes (T1D) is essential to minimizing long-term risk of complications. We used the T1D Exchange database from 58 US diabetes clinics to identify differences in diabetes management characteristics among children categorized as having excellent vs. poor glycemic control. Among registry participants 6-17 yr old with diabetes duration ≥ 2 yr, those with excellent control [(A1c <7%)(53 mmol/mol) (N = 588)] were compared with those with poor control [(A1c ≥ 9% )(75 mmol/mol) (N = 2684)] using logistic regression. The excellent and poor control groups differed substantially in diabetes management (p < 0.001 for all) with more of the excellent control group using insulin pumps, performing blood glucose monitoring ≥ 5 ×/d, missing fewer boluses, bolusing before meals rather than at the time of or after a meal, using meal-specific insulin:carbohydrate ratios, checking their blood glucose prior to giving meal time insulin, giving insulin for daytime snacks, giving more bolus insulin, and using a lower mean total daily insulin dose than those in poor control. After adjusting for demographic and socioeconomic factors, diabetes management characteristics were still strongly associated with good vs. poor control. Notably, frequency of severe hypoglycemia was similar between the groups while DKA was more common in the poorly controlled group. Children with excellent glycemic control tend to exhibit markedly different diabetes self-management techniques than those with poor control. This knowledge may further inform diabetes care providers and patients about specific characteristics and behaviors that can be augmented to potentially improve glycemic control. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Assessment of training and technical assistance needs of Colorectal Cancer Control Program Grantees in the U.S.

    PubMed

    Escoffery, Cam; Hannon, Peggy; Maxwell, Annette E; Vu, Thuy; Leeman, Jennifer; Dwyer, Andrea; Mason, Caitlin; Sowles, Shaina; Rice, Ketra; Gressard, Lindsay

    2015-01-31

    Practitioners often require training and technical assistance to build their capacity to select, adapt, and implement evidence-based interventions (EBIs). The CDC Colorectal Cancer Control Program (CRCCP) aims to promote CRC screening to increase population-level screening. This study identified the training and technical assistance (TA) needs and preferences for training related to the implementation of EBIs among CRCCP grantees. Twenty-nine CRCCP grantees completed an online survey about their screening activities, training and technical assistance in 2012. They rated desire for training on various evidence-based strategies to increase cancer screening, evidence-based competencies, and program management topics. They also reported preferences for training formats and facilitators and barriers to trainings. Many CRCCP grantees expressed the need for training with regards to specific EBIs, especially system-level and provider-directed EBIs to promote CRC screening. Grantees rated these EBIs as more difficult to implement than client-oriented EBIs. Grantees also reported a moderate need for training regarding finding EBIs, assessing organizational capacity, implementing selected EBIs, and conducting process and outcome evaluations. Other desired training topics reported with higher frequency were partnership development and data collection/evaluation. Grantees preferred training formats that were interactive such as on-site trainings, webinars or expert consultants. Public health organizations need greater supports for adopting evidence-based interventions, working with organizational-level change, partnership development and data management. Future capacity building efforts for the adoption of EBIs should focus on systems or provider level interventions and key processes for health promotion and should be delivered in a variety of ways to assist local organizations in cancer prevention and control.

  3. Two beam energy exchange in hybrid liquid crystal cells with photorefractive field controlled boundary conditions

    NASA Astrophysics Data System (ADS)

    Reshetnyak, V. Yu.; Pinkevych, I. P.; Subota, S. I.; Evans, D. R.

    2016-09-01

    We develop a theory describing energy gain when two light beams intersect in a hybrid nematic liquid crystal (LC) cell with photorefractive crystalline substrates. A periodic space-charge field induced by interfering light beams in the photorefractive substrates penetrates into the LC layer and reorients the director. We account for two main mechanisms of the LC director reorientation: the interaction of the photorefractive field with the LC flexopolarization and the director easy axis at the cell boundaries. It is shown that the resulting director grating is a sum of two in-phase gratings: the flexoelectric effect driven grating and the boundary-driven grating. Each light beam diffracts from the induced gratings leading to an energy exchange between beams. We evaluate the signal beam gain coefficient and analyze its dependence on the director anchoring energy and the magnitude of the director easy axis modulation.

  4. Controllable Synthesis of Mn6+ Doped Nanoparticles by a Facile Anion Exchange Method

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaowen; Li, Yang; Liao, Chenxing; Chen, Zhi; Qiu, Jianrong

    2017-01-01

    Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1400 nm) is attracting extensive attention. Mn6+ doped BaSO4 with broadband emission from 900 nm to 1400 nm is emerging as a new class of NIR phosphor for fluorescence imaging. Manganese has diverse valence states, thus it is difficult to prevent valence change of Mn6+ during traditional synthesis process. In this work, BaSO4:Mn6+ nanoparticles with uniform size and morphology were first successfully prepared through a fast liquid-solid solution route at room temperature. The nanoparticles exhibit broadband NIR emission from Mn6+ when excited by 808 nm lasers. This convenient strategy, based on an efficient anion exchange reaction, is proved effective for synthesizing nano-sized materials. The results reveal that our strategy has great potential in fabricating special valence state ion doped nanomaterials.

  5. Synthesis of L1{sub 0}-FePt perpendicular films with controllable coercivity and intergranular exchange coupling by interfacial microstructure control

    SciTech Connect

    Feng Chun; Zhang En; Yang Meiyin; Li Ning; Jiang Yong; Yu Guanghua; Li Baohe

    2010-06-15

    A series of FePtBi/Au multilayers were fabricated by magnetron sputtering. The interfacial microstructure control of Bi and Au atoms and its effect on comprehensive properties of L1{sub 0}-FePt perpendicular films were carefully studied. Results show that: perpendicular magnetic anisotropy of the L1{sub 0}-FePt film can be remarkably enhanced with the epitaxial inducement of Au atoms. On the other hand, intergranular exchange coupling (IEC) of the film is greatly decreased due to the isolation of FePt particles by nonmagnetic Au particles. Moreover, the controllable coercivity of the film can be realized by adjusting ordering degree of the film through diffusion of Bi atoms. Thus, an L1{sub 0}-FePt perpendicular film with controllable coercivity and no IEC is realized with the interfacial microstructure control of surfactant Bi and Au atoms.

  6. Technical Basis for Physical Fidelity of NRC Control Room Training Simulators for Advanced Reactors

    SciTech Connect

    Minsk, Brian S.; Branch, Kristi M.; Bates, Edward K.; Mitchell, Mark R.; Gore, Bryan F.; Faris, Drury K.

    2009-10-09

    The objective of this study is to determine how simulator physical fidelity influences the effectiveness of training the regulatory personnel responsible for examination and oversight of operating personnel and inspection of technical systems at nuclear power reactors. It seeks to contribute to the U.S. Nuclear Regulatory Commission’s (NRC’s) understanding of the physical fidelity requirements of training simulators. The goal of the study is to provide an analytic framework, data, and analyses that inform NRC decisions about the physical fidelity requirements of the simulators it will need to train its staff for assignment at advanced reactors. These staff are expected to come from increasingly diverse educational and experiential backgrounds.

  7. 76 FR 11327 - Technical Amendments to Rule 17a-8: Financial Recordkeeping and Reporting of Currency and Foreign...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE... Currency and Foreign Transactions AGENCY: Securities and Exchange Commission. ACTION: Final rule; technical amendments. SUMMARY: The Securities and Exchange Commission (``Commission'') is adopting technical...

  8. Patterns and controls of CO2 exchange from developed land in the mid-continental United States

    NASA Astrophysics Data System (ADS)

    McFadden, J. P.; Balogun, A. A.; Bauer, M. E.; Peters, E. B.; Wu, J.

    2006-12-01

    heat stress conditions. Differences in daytime net CO2 uptake (primarily due to stomatal control on uptake during warm afternoons) more strongly controlled the daily net exchange than did differences in respiration. New QuickBird and Landsat imagery was acquired concurrently with the 2006 field sampling campaign to develop an improved classification and a set of biophysically driven algorithms to scale carbon exchange from the major classes of residential developed land.

  9. HVAC System Automatic Controls and Indoor Air Quality in Schools. Technical Bulletin.

    ERIC Educational Resources Information Center

    Wheeler, Arthur E.

    Fans, motors, coils, and other control components enable a heating, ventilating, and air-conditioning (HVAC) system to function smoothly. An explanation of these control components and how they make school HVAC systems work is provided. Different systems may be compared by counting the number of controlled devices that are required. Control…

  10. HVAC System Automatic Controls and Indoor Air Quality in Schools. Technical Bulletin.

    ERIC Educational Resources Information Center

    Wheeler, Arthur E.

    Fans, motors, coils, and other control components enable a heating, ventilating, and air-conditioning (HVAC) system to function smoothly. An explanation of these control components and how they make school HVAC systems work is provided. Different systems may be compared by counting the number of controlled devices that are required. Control…

  11. Phase 1 engineering and technical data report for the thermal control extravehicular life support system

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A shuttle EVLSS Thermal Control System (TCS) is defined. Thirteen heat rejection subsystems, thirteen water management subsystems, nine humidity control subsystems, three pressure control schemes and five temperature control schemes are evaluated. Sixteen integrated TCS systems are studied, and an optimum system is selected based on quantitative weighting of weight, volume, cost, complexity and other factors. The selected sybsystem contains a sublimator for heat rejection, a bubble expansion tank for water management, and a slurper and rotary separator for humidity control. Design of the selected subsystem prototype hardware is presented.

  12. Results of in-situ biofouling control, and corrosion test at Punta Tuna, Puerto Rico and its significance on OTEC heater exchanger design

    SciTech Connect

    Sasscer, D.S.; Morgan, T.O.; Tosteson, T.R.

    1983-06-01

    Because Ocean Thermal Energy Conversion (OTEC) operates at a low thermodynamic efficiency, heat exchangers represent a major portion of the overall cost of an OTEC power plant. For this reason, the commercial viability of OTEC depends on the design of efficient and inexpensive heat exchangers which have an operational life expectancy of 20 to 30 years and which can be maintained at a high level of efficiency by the use of effective biofouling control. Summarized here are the results of experiments conducted by the Center for Energy and Environment Research of the University of Puerto Rico to: determine the nature of the biofilm which develops on heat exchanger surfaces exposed to running seawater, test the effectiveness of brush cleaning and chlorination in controlling biofouling on these surfaces and study the corrosion behavior of zinc protected aluminum alloys under OTEC conditions in an attempt to qualify them for use in low cost OTEC heat exchangers.

  13. Innovative traffic control: Technology practice in Europe. International technology exchange program

    SciTech Connect

    Tignor, S.C.; Brown, L.L.; Butner, J.L.; Cunard, R.; Davis, S.C.

    1999-08-01

    This summary report describes a may 1998 transportation technology scanning tour of four European countries. The tour was co-sponsored by FHWA, AASHTO, and TRB. The tour team consisted of 10 traffic engineers who visited England, France, Germany, and Sweden to observe traffic control devices and methodology and to determine if any European practices should and could be recommended for use in the United States. This report is organized into five key chapters: Traffic Control Devices, Freeway Control, Operational Practices, Information Management, and Administrative Practices. Among the devices and practices recommended for further study for US adoption are specific freeway pavement markings, variable speed control, lane control signals, intelligent speed adaptation, innovative intersection control, and variable message signs that incorporate pictograms. The report includes statements for proposed research problems.

  14. Sediment-water exchange of nutrients in the Marsdiep basin, western Wadden Sea: Phosphorus limitation induced by a controlled release?

    NASA Astrophysics Data System (ADS)

    Leote, Catarina; Epping, Eric H. G.

    2015-01-01

    To quantify the release of inorganic phosphorus from the sediments and assess its contribution to present primary production, a basin-wide study of the Marsdiep (western Wadden Sea, The Netherlands) was performed. Two distinct sedimentary zones were identified: a depositional area characterized by a high content of silt and organic carbon and a small grain size and the majority of the area, composed of fine/medium sand and a low organic carbon content. The sediment-water exchange was higher in the fine grained depositional area and based on a relationship found between the release of inorganic phosphorus and the silt content, a total annual release of 1.0×107 mol P was estimated for the whole Marsdiep basin. A spatial variability in the processes controlling the nutrient release was found. The exchange in the depositional area resulted mainly from molecular diffusive transport, with mineralization and sorption determining the concentration of inorganic phosphorus in the porewater. For the coarser sediment stations the activity of macrofauna clearly enhanced the fluxes. Given the relative demand of nutrients (N:P:Si) for phytoplankton growth, the release was phosphorus deficient during most of the year. Nevertheless, it increased from February until September, in parallel with the increase in temperature and light, thus having the potential to fuel primary production during their seasonal growth period. In terms of absolute values, our results show that the present exchange, enhanced by the activity of macrofauna has the potential to fuel a significant fraction of the recent levels of primary productivity.

  15. Processes Controlling Air-Sea Exchange of CO2 in a Subtropical Pacific Estuary

    NASA Astrophysics Data System (ADS)

    Fagan, K. E.; MacKenzie, F. T.; Andersson, A. J.

    2004-12-01

    In contrast to the open ocean, shallow-water coastal ocean air-sea CO2 exchange has been given relatively little attention. Available data suggest that continental shelves may act as sinks for atmospheric CO2 while estuaries, coral reefs, and upwelling regions, in general may act as sources. However, all data do not comply with these general trends and the data available are geographically relatively scarce and short in duration. Consequently, at the time, it is not possible to unequivocally conclude whether the global shallow-water ocean acts as a source or a sink of atmospheric CO2. The present study represents the first evaluation of air-sea CO2 exchange for a subtropical high island of the Pacific. Kaneohe Bay, located on the eastern side of Oahu, Hawaii, is a complex estuarine system with a large barrier coral reef, numerous patch reefs, and several riverine inputs. Since Sep 2003 surface water has been collected bimonthly throughout the bay for total alkalinity (TA) and dissolved inorganic carbon (DIC) analysis. The partial pressure of carbon dioxide (PCO2) is calculated using TA, DIC, and constants from Mehrbach et al. (1973), refit by Dickson and Millero (1987). For all data collected before Dec 2003, PCO2s were above the atmospheric level (375 uatm) for all sites throughout the bay (400 to 1300 uatm). The highest values occurred at sites within Kaneohe Stream. The lowest values, still above atmospheric concentration, occurred at sites outside the barrier reef, indicating that high surface water PCO2s extend beyond the boundaries of the bay. Two large storms occurred at the end of Nov 2003 and the end of Feb 2004 that dramatically reduced PCO2s to at or below the atmospheric partial pressure throughout the entire bay. This appears to be the result of increased river runoff adding excess nutrients to the bay that enhanced photosynthesis throughout the bay thereby drawing down surface water CO2. Despite the significant effects of the storms, average PCO2s for

  16. Studies of magnetism and exchange scattering in solids using synchrotron radiation and spin polarized photoemission. Final technical report, June 1, 1981-May 31, 1984

    SciTech Connect

    Rothberg, G.M.

    1984-01-01

    Progress has been made toward developing Spin Polarized EXAFS (SPEXAFS) as a technique for studying magnetism in solids. The first observations have been made of EXAFS by means of photoemission with sufficient data to permit a traditional Fourier-transform analysis of atomic structure. Some of the advantages of photoelectron detection of EXAFS are: (1) vuv light may be used thereby extending greatly the useable range of photon energies; (2) the number of elements that may be studied for surface EXAFS is increased; (3) the possibility exists for measurements that cannot be done in other ways. In addition to its intrinsic interest, this result is crucial to the study of the spin dependence of EXAFS. These measurements were carried out on the vuv storage ring at the National Synchrotron Light Source. Data obtained on the spin dependence of EXAFS in MnF/sub 2/ at room temperature tentatively show dependence of the Mn absorber atom phase shift on the exchange interaction within the absorber atom. This effect has not been discussed theoretically. Preliminary observations have been made of the Fano resonance in Mn 3d photoemission at the 3p to 3d threshold.

  17. Mechanical engineering department technical review

    SciTech Connect

    Carr, R.B. Denney, R.M.

    1981-01-01

    The Mechanical Engineering Department Technical Review is published to: (1) inform the readers of various technical activities within the department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical acievements and publication abstracts. The first is divided into eight sections, one for each division in the department providing the reader with the names of the personnel and the division accomplishing the work.

  18. Mechanical Engineering Department. Technical review

    SciTech Connect

    Simecka, W.B.; Condouris, R.A.; Talaber, C.

    1980-01-01

    The Mechanical Engineering Department Technical Review is published to (1) inform the readers of various technical activities within the Department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical achievements and publication abstracts. The first is divided into eight sections, one for each Division in the Department providing the reader with the names of the personnel and the Division accomplishing the work.

  19. Mechanical Engineering Department Technical Review

    SciTech Connect

    Carr, R.B.; Denney, R.M.

    1981-07-01

    The Mechanical Engineering Department Technical Review is published to inform readers of various technical activities within the Department, promote exchange of ideas, and give credit to personnel who are achieving the results. The report is presented in two parts: technical achievements and publication abstracts. The first is divided into seven sections, each of which reports on an engineering division and its specific activities related to nuclear tests, nuclear explosives, weapons, energy systems, engineering sciences, magnetic fusion, and materials fabrication.

  20. Mechanical Engineering Department technical abstracts

    SciTech Connect

    Denney, R.M.

    1982-07-01

    The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts.

  1. Secondary effects of anion exchange on chloride, sulfate, and lead release: systems approach to corrosion control.

    PubMed

    Willison, Hillary; Boyer, Treavor H

    2012-05-01

    Water treatment processes can cause secondary changes in water chemistry that alter finished water quality including chloride, sulfate, natural organic matter (NOM), and metal release. Hence, the goal of this research was to provide an improved understanding of the chloride-to-sulfate mass ratio (CSMR) with regards to chloride and sulfate variations at full-scale water treatment plants and corrosion potential under simulated premise plumbing conditions. Laboratory corrosion studies were conducted using Pb-Sn solder/Cu tubing galvanic cells exposed to model waters with low (approx. 5 mg/L Cl(-) and 10 mg/L SO(4)(2-)) and high (approx. 50 mg/L Cl(-) and 100 mg/L SO(4)(2-)) concentrations of chloride and sulfate at a constant CSMR of ≈ 0.5. The role of NOM during corrosion was also evaluated by changing the type of organic material. In addition, full-scale sampling was conducted to quantify the raw water variability of chloride, sulfate, and NOM concentrations and the changes to these parameters from magnetic ion exchange treatment. Test conditions with higher concentrations of chloride and sulfate released significantly more lead than the lower chloride and sulfate test waters. In addition, the source of NOM was a key factor in the amount of lead released with the model organic compounds yielding significantly less lead release than aquatic NOM.

  2. Competitive ion-exchange adsorption of proteins: competitive isotherms with controlled competitor concentration.

    PubMed

    Cano, Tony; Offringa, Natalie D; Willson, Richard C

    2005-06-24

    The competitive adsorption processes inevitably present in chromatographic separations of complex mixtures have not been extensively studied. This is partly due to the difficulty of measuring true competitive isotherms, in which all system parameters (including competitor concentrations) are held constant. We report a novel approach to determining competitive protein adsorption isotherms in which the competitor concentration is held constant across the entire isotherm. By using the heme prosthetic group in cytochrome b5 as a quantitative spectrophotometric label, competitive isotherms between cytochrome b5 and alpha-lactalbumin can be constructed. Similarly, manganese-substituted protoporphyrin IX heme replacement allows the non-perturbing labeling of individual cytochrome b5 conservative surface charge mutants by replacement of a single atom in the interior of the protein. This labeling allows the study of competition between cytochrome b5 charge mutants of identical size and shape, which differ only in charge arrangement. Using these techniques, the effect of competing species on equilibrium behavior and the apparent heterogeneity of anion-exchange adsorbents in the presence of competitors can be quantitatively studied by fitting the data to two popular single-component binding models, the Temkin and the Langmuir-Freundlich (L-F) isotherms.

  3. Controlled rotation mechanism of DNA strand exchange by the Hin serine recombinase

    PubMed Central

    Xiao, Botao; McLean, Meghan M.; Lei, Xianbin; Marko, John F.; Johnson, Reid C.

    2016-01-01

    DNA strand exchange by serine recombinases has been proposed to occur by a large-scale rotation of halves of the recombinase tetramer. Here we provide the first direct physical evidence for the subunit rotation mechanism for the Hin serine invertase. Single-DNA looping assays using an activated mutant (Hin-H107Y) reveal specific synapses between two hix sites. Two-DNA “braiding” experiments, where separate DNA molecules carrying a single hix are interwound, show that Hin-H107Y cleaves both hix sites and mediates multi-step rotational relaxation of the interwinding. The variable numbers of rotations in the DNA braid experiments are in accord with data from bulk experiments that follow DNA topological changes accompanying recombination by the hyperactive enzyme. The relatively slow Hin rotation rates, combined with pauses, indicate considerable rotary friction between synapsed subunit pairs. A rotational pausing mechanism intrinsic to serine recombinases is likely to be crucial for DNA ligation and for preventing deleterious DNA rearrangements. PMID:27032966

  4. Controlled rotation mechanism of DNA strand exchange by the Hin serine recombinase.

    PubMed

    Xiao, Botao; McLean, Meghan M; Lei, Xianbin; Marko, John F; Johnson, Reid C

    2016-04-01

    DNA strand exchange by serine recombinases has been proposed to occur by a large-scale rotation of halves of the recombinase tetramer. Here we provide the first direct physical evidence for the subunit rotation mechanism for the Hin serine invertase. Single-DNA looping assays using an activated mutant (Hin-H107Y) reveal specific synapses between two hix sites. Two-DNA "braiding" experiments, where separate DNA molecules carrying a single hix are interwound, show that Hin-H107Y cleaves both hix sites and mediates multi-step rotational relaxation of the interwinding. The variable numbers of rotations in the DNA braid experiments are in accord with data from bulk experiments that follow DNA topological changes accompanying recombination by the hyperactive enzyme. The relatively slow Hin rotation rates, combined with pauses, indicate considerable rotary friction between synapsed subunit pairs. A rotational pausing mechanism intrinsic to serine recombinases is likely to be crucial for DNA ligation and for preventing deleterious DNA rearrangements.

  5. Hydrologic and geomorphic controls on hyporheic exchange during base flow recession in a headwater mountain stream

    Treesearch

    A.S. Ward; M. Fitzgerald; M.N. Gooseff; A.M. Binley; K. Singha

    2012-01-01

    Hyporheic hydrodynamics are a control on stream ecosystems, yet we lack a thorough understanding of catchment controls on these flow paths, including valley constraint and hydraulic gradients in the valley bottom. We performed four whole-stream solute tracer injections under steady state flow conditions at the H. J. Andrews Experimental Forest (Oregon, United States)...

  6. Sensor guided control and navigation with intelligent machines. Final technical report

    SciTech Connect

    Ghosh, Bijoy K.

    2001-03-26

    This item constitutes the final report on ''Visionics: An integrated approach to analysis and design of intelligent machines.'' The report discusses dynamical systems approach to problems in robust control of possibly time-varying linear systems, problems in vision and visually guided control, and, finally, applications of these control techniques to intelligent navigation with a mobile platform. Robust design of a controller for a time-varying system essentially deals with the problem of synthesizing a controller that can adapt to sudden changes in the parameters of the plant and can maintain stability. The approach presented is to design a compensator that simultaneously stabilizes each and every possible mode of the plant as the parameters undergo sudden and unexpected changes. Such changes can in fact be detected by a visual sensor and, hence, visually guided control problems are studied as a natural consequence. The problem here is to detect parameters of the plant and maintain st ability in the closed loop using a ccd camera as a sensor. The main result discussed in the report is the role of perspective systems theory that was developed in order to analyze such a detection and control problem. The robust control algorithms and the visually guided control algorithms are applied in the context of a PUMA 560 robot arm control where the goal is to visually locate a moving part on a mobile turntable. Such problems are of paramount importance in manufacturing with a certain lack of structure. Sensor guided control problems are extended to problems in robot navigation using a NOMADIC mobile platform with a ccd and a laser range finder as sensors. The localization and map building problems are studied with the objective of navigation in an unstructured terrain.

  7. Probing core and shell contributions to exchange bias in Co /Co3O4 nanoparticles of controlled size

    NASA Astrophysics Data System (ADS)

    De, D.; Iglesias, Óscar; Majumdar, S.; Giri, Saurav

    2016-11-01

    Coupling at the interface of core/shell magnetic nanoparticles is known to be responsible for exchange bias (EB) and the relative sizes of core and shell components are supposed to influence the associated phenomenology. In this work, we have prepared core/shell structured nanoparticles with a total average diameter around ˜27 nm and a wide range of shell thicknesses through the controlled oxidation of Co nanoparticles well dispersed in an amorphous silica host. Structural characterizations give compelling evidence of the formation of Co3O4 crystallite phase at the shells surrounding the Co core. Field cooled hysteresis loops display nonmonotonous dependence of the exchange bias HE and coercive HC fields, that become maximum for a sample with an intermediate shell thickness, at which lattice strain is also maximum for both phases. The EB effects persist up to temperatures above the ordering temperature of the oxide shell. Results of our atomistic Monte Carlo simulations of particles with the same size and composition as in experiments are in agreement with the experimental observations and have allowed us to identify a change in the contribution of the interfacial surface spins to the magnetization reversal, giving rise to the observed maximum in HE and HC.

  8. Simultaneous Kerr and Faraday investigations of boundary magnetization and order parameter switching in voltage-controllable exchange bias films

    NASA Astrophysics Data System (ADS)

    Wang, Junlei; Echtenkamp, Will; Street, Mike; Binek, Christian

    2015-03-01

    Magnetoelectric oxides are of great interest for ultra-low power spintronics with memory and logic function. A key property for the realization of electrically switchable state variables is the voltage-controlled boundary magnetization in magnetoelectric antiferromagnets. It allows electric switching of an adjacent exchange coupled ferromagnetic layer in the absence of dissipative currents. Previous surface sensitive measurements of boundary magnetization in thin films of the archetypical magnetoelectric antiferromagnet chromia lacked explicit demonstration of the predicted rigid coupling between the bulk antiferromagnetic order parameter and the boundary magnetization. We designed a magneto-optical setup allowing simultaneous measurement of Kerr and Faraday rotation. Our experiments correlate electric field induced bulk magneto-optical effects (non-reciprocal rotation), including the response on switching of the antiferromagnetic order parameter, with the boundary magnetization. Our results suggest that switching of a ferromagnetic film strongly exchange coupled to a magnetoelectric antiferromagnetic ultra-thin film allows switching of the antiferromagnetic order parameter. We investigate the possibility that this switching phenomenon might induce a voltage pulse via a generalized variation of the inverse linear magnetoelectric effect. This project was supported by SRC through CNFD, an SRC-NRI Center, by C-SPIN, part of STARnet, and by the NSF through MRSEC.

  9. A Data Base of Nutrient Use, Water Use, CO2 Exchange, and Ethylene Production by Soybeans in a Controlled Environment

    NASA Technical Reports Server (NTRS)

    Wheeler, R. M.; Mackowiak, C. L.; Peterson, B. V.; Sager, J. C.; Knott, W. M.; Berry, W. L.; Sharifi, M. R.

    1998-01-01

    A data set is given describing daily nutrient and water uptake, carbon dioxide (CO2) exchange, ethylene production, and carbon and nutrient partitioning from a 20 sq m stand of soybeans (Glycine max (L.) Merr. cv. McCall] for use in bioregenerative life support systems. Stand CO2 exchange rates were determined from nocturnal increases in CO2 (respiration) and morning drawdowns (net photosynthesis) to a set point of 1000 micromol/ mol each day (i.e., a closed system approach). Atmospheric samples were analyzed throughout growth for ethylene using gas chromatography with photoionization detection (GC/PH)). Water use was monitored by condensate production from the humidity control system, as well as water uptake from the nutrient solution reservoirs each day. Nutrient uptake data were determined from daily additions of stock solution and acid to maintain an EC of 0.12 S/m and pH of 5.8. Dry mass yields of seeds, pods (without seeds), leaves, stems, and roots are provided, as well as elemental and proximate nutritional compositions of the tissues. A methods section is included to qualify any assumptions that might be required for the use of the data in plant growth models, along with a daily event calendar documenting set point adjustments and the occasional equipment or sensor failure.

  10. The Advantages of Abstract Control Knowledge in Expert System Design. Technical Report #7.

    ERIC Educational Resources Information Center

    Clancey, William J.

    This paper argues that an important design principle for building expert systems is to represent all control knowledge abstractly and separately from the domain knowledge upon which it operates. Abstract control knowledge is defined as the specifications of when and how a program is to carry out its operations, such as pursuing a goal, focusing,…

  11. INTEGRATED AIR POLLUTION CONTROL SYSTEM VERSION 5.0 - VOLUME 2: TECHNICAL DOCUMENTATION

    EPA Science Inventory

    The three volume report and two diskettes document the Integrated Air Pollution Control System (IAPCS), developed for the U.S. EPA to estimate costs and performance for emission control systems applied to coal-fired utility boilers. The model can project a material balance, an eq...

  12. INTEGRATED AIR POLLUTION CONTROL SYSTEM, VERSION 4.0 - VOLUME 2: TECHNICAL DOCUMENTATION MANUAL

    EPA Science Inventory

    The Integrated Air Pollution Control System (IAPCS) was developed for the U.S. EPA's Air and Energy Engineering Research Laboratory to estimate costs and performance for emission control systems applied to coal-fired utility boilers. The model can project a material balance, and ...

  13. Learner Control of Instructional Sequencing within an Adaptive Tutorial CAI Environment. Technical Report 75-7.

    ERIC Educational Resources Information Center

    Seidel, Robert J.; And Others

    A study to test the effects of learner control of the sequencing of instructional tasks when using computer-assisted instruction (CAI) systems is described. Using a series of CAI modules to teach the COBOL programing language to military personnel, students were able to control various aspects of their learning environment. Among the research…

  14. INTEGRATED AIR POLLUTION CONTROL SYSTEM, VERSION 4.0 - VOLUME 2: TECHNICAL DOCUMENTATION MANUAL

    EPA Science Inventory

    The Integrated Air Pollution Control System (IAPCS) was developed for the U.S. EPA's Air and Energy Engineering Research Laboratory to estimate costs and performance for emission control systems applied to coal-fired utility boilers. The model can project a material balance, and ...

  15. INTEGRATED AIR POLLUTION CONTROL SYSTEM VERSION 5.0 - VOLUME 2: TECHNICAL DOCUMENTATION

    EPA Science Inventory

    The three volume report and two diskettes document the Integrated Air Pollution Control System (IAPCS), developed for the U.S. EPA to estimate costs and performance for emission control systems applied to coal-fired utility boilers. The model can project a material balance, an eq...

  16. Technical Report on Occupations in Numerically Controlled Metal-Cutting Machining.

    ERIC Educational Resources Information Center

    Manpower Administration (DOL), Washington, DC. U.S. Employment Service.

    At the present time, only 5 percent of the short-run metal-cutting machining in the United States is done by numerically controlled machined tools, but within the next decade it is expected to increase by 50 percent. Numerically controlled machines use taped data which is changed into instructions and directs the machine to do certain steps…

  17. Pollution control technical manual: Lurgi oil shale retorting with open pit mining. Final report

    SciTech Connect

    Not Available

    1983-04-01

    The Lurgi oil shale PCTM addresses the Lurgi retorting technology, developed by Lurgi Kohle and Mineralotechnik GmbH, West Germany, in the manner in which this technology may be applied to the oil shales of the western United States. This manual proceeds through a description of the Lurgi oil shale plant proposed by Rio Blanco Oil Shale Company, characterizes the waste streams produced in each medium, and discusses the array of commercially available controls which can be applied to the Lurgi plant waste streams. From these generally characterized controls, several are examined in more detail for each medium in order to illustrate typical control technology operation. Control technology cost and performance estimates are presented, together with descriptions of the discharge streams, secondary waste streams and energy requirements. A summary of data limitations and needs for environmental and control technology considerations is presented.

  18. A feedback linearization approach to spacecraft control using momentum exchange devices. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Dzielski, John Edward

    1988-01-01

    Recent developments in the area of nonlinear control theory have shown how coordiante changes in the state and input spaces can be used with nonlinear feedback to transform certain nonlinear ordinary differential equations into equivalent linear equations. These feedback linearization techniques are applied to resolve two problems arising in the control of spacecraft equipped with control moment gyroscopes (CMGs). The first application involves the computation of rate commands for the gimbals that rotate the individual gyroscopes to produce commanded torques on the spacecraft. The second application is to the long-term management of stored momentum in the system of control moment gyroscopes using environmental torques acting on the vehicle. An approach to distributing control effort among a group of redundant actuators is described that uses feedback linearization techniques to parameterize sets of controls which influence a specified subsystem in a desired way. The approach is adapted for use in spacecraft control with double-gimballed gyroscopes to produce an algorithm that avoids problematic gimbal configurations by approximating sets of gimbal rates that drive CMG rotors into desirable configurations. The momentum management problem is stated as a trajectory optimization problem with a nonlinear dynamical constraint. Feedback linearization and collocation are used to transform this problem into an unconstrainted nonlinear program. The approach to trajectory optimization is fast and robust. A number of examples are presented showing applications to the proposed NASA space station.

  19. Dynamic C and N stocks - key factors controlling the C gas exchange of maize in a heterogenous peatland

    NASA Astrophysics Data System (ADS)

    Pohl, M.; Hoffmann, M.; Hagemann, U.; Giebels, M.; Albiac Borraz, E.; Sommer, M.; Augustin, J.

    2014-11-01

    Drainage and cultivation of fen peatlands creates complex small-scale mosaics of soils with extremely variable soil organic carbon (SOC) stocks and groundwater-level (GWL). To date, it remains unclear if such sites are sources or sinks for greenhouse gases like CO2 and CH4, especially if used for cropland. As individual control factors like GWL fail to account for this complexity, holistic approaches combining gas fluxes with the underlying processes are required to understand the carbon (C) gas exchange of drained fens. It can be assumed that the stocks of SOC and N located above the variable GWL - defined as dynamic C and N stocks - play a key role in the regulation of plant- and microbially mediated C gas fluxes of these soils. To test this assumption, the present study analysed the C gas exchange (gross primary production - GPP, ecosystem respiration - Reco, net ecosystem exchange - NEE, CH4) of maize using manual chambers for four years. The study sites were located near Paulinenaue, Germany. Here we selected three soils, which represent the full gradient in pedogenesis, GWL and SOC stocks (0-1 m) of the fen peatland: (a) Haplic Arenosol (AR; 8 kg C m-2); (b) Mollic Gleysol (GL; 38 kg C m-2); and (c) Hemic Histosol (HS; 87 kg C m-2). Daily GWL data was used to calculate dynamic SOC (SOCdyn) and N (Ndyn) stocks. Average annual NEE differed considerably among sites, ranging from 47 ± 30 g C m-2 a-1 at AR to -305 ± 123 g C m-2 a-1 at GL and -127 ± 212 g C m-2 a-1 at HS. While static SOC and N stocks showed no significant effect on C fluxes, SOCdyn and Ndyn and their interaction with GWL strongly influenced the C gas exchange, particularly NEE and the GPP:Reco ratio. Moreover, based on nonlinear regression analysis, 86% of NEE variability was explained by GWL and SOCdyn. The observed high relevance of dynamic SOC and N stocks in the aerobic zone for plant and soil gas exchange likely originates from the effects of GWL-dependent N availability on C formation and

  20. Dynamic C and N stocks - key factors controlling the C gas exchange of maize in heterogenous peatland

    NASA Astrophysics Data System (ADS)

    Pohl, M.; Hoffmann, M.; Hagemann, U.; Giebels, M.; Albiac Borraz, E.; Sommer, M.; Augustin, J.

    2015-05-01

    The drainage and cultivation of fen peatlands create complex small-scale mosaics of soils with extremely variable soil organic carbon (SOC) stocks and groundwater levels (GWLs). To date, the significance of such sites as sources or sinks for greenhouse gases such as CO2 and CH4 is still unclear, especially if the sites are used for cropland. As individual control factors such as GWL fail to account for this complexity, holistic approaches combining gas fluxes with the underlying processes are required to understand the carbon (C) gas exchange of drained fens. It can be assumed that the stocks of SOC and N located above the variable GWL - defined as dynamic C and N stocks - play a key role in the regulation of the plant- and microbially mediated CO2 fluxes in these soils and, inversely, for CH4. To test this assumption, the present study analysed the C gas exchange (gross primary production - GPP; ecosystem respiration - Reco; net ecosystem exchange - NEE; CH4) of maize using manual chambers for 4 years. The study sites were located near Paulinenaue, Germany, where we selected three soil types representing the full gradient of GWL and SOC stocks (0-1 m) of the landscape: (a) Haplic Arenosol (AR; 8 kg C m-2); (b) Mollic Gleysol (GL; 38 kg C m-2); and (c) Hemic Histosol (HS; 87 kg C m-2). Daily GWL data were used to calculate dynamic SOC (SOCdyn) and N (Ndyn) stocks. Average annual NEE differed considerably among sites, ranging from 47 ± 30 g C m-2 yr-1 in AR to -305 ± 123 g C m-2 yr-1 in GL and -127 ± 212 g C m-2 yr-1 in HS. While static SOC and N stocks showed no significant effect on C fluxes, SOCdyn and Ndyn and their interaction with GWL strongly influenced the C gas exchange, particularly NEE and the GPP : Reco ratio. Moreover, based on nonlinear regression analysis, 86% of NEE variability was explained by GWL and SOCdyn. The observed high relevance of dynamic SOC and N stocks in the aerobic zone for plant and soil gas exchange likely originates from the

  1. On the role of exchange of power and information signals in control and stability of the human-robot interaction

    NASA Technical Reports Server (NTRS)

    Kazerooni, H.

    1991-01-01

    A human's ability to perform physical tasks is limited, not only by his intelligence, but by his physical strength. If, in an appropriate environment, a machine's mechanical power is closely integrated with a human arm's mechanical power under the control of the human intellect, the resulting system will be superior to a loosely integrated combination of a human and a fully automated robot. Therefore, we must develop a fundamental solution to the problem of 'extending' human mechanical power. The work presented here defines 'extenders' as a class of robot manipulators worn by humans to increase human mechanical strength, while the wearer's intellect remains the central control system for manipulating the extender. The human, in physical contact with the extender, exchanges power and information signals with the extender. The aim is to determine the fundamental building blocks of an intelligent controller, a controller which allows interaction between humans and a broad class of computer-controlled machines via simultaneous exchange of both power and information signals. The prevalent trend in automation has been to physically separate the human from the machine so the human must always send information signals via an intermediary device (e.g., joystick, pushbutton, light switch). Extenders, however are perfect examples of self-powered machines that are built and controlled for the optimal exchange of power and information signals with humans. The human wearing the extender is in physical contact with the machine, so power transfer is unavoidable and information signals from the human help to control the machine. Commands are transferred to the extender via the contact forces and the EMG signals between the wearer and the extender. The extender augments human motor ability without accepting any explicit commands: it accepts the EMG signals and the contact force between the person's arm and the extender, and the extender 'translates' them into a desired position. In

  2. Exchange coupling controlled ferrite with dual magnetic resonance and broad frequency bandwidth in microwave absorption

    PubMed Central

    Jia, Jingguo; Liu, Chuyang; Ma, Ning; Han, Gaorong; Weng, Wenjian; Du, Piyi

    2013-01-01

    Ti-doped barium ferrite powders BaFe12−xTixO19 (x = 0, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) were synthesized by the sol–gel method. The phase structure and morphology were analyzed by x-ray diffraction (XRD) and scanning electron microscopy, respectively. The powders were also studied for their magnetic properties and microwave absorption. Results show that the Ti-doped barium ferrites (BFTO) exist in single phase and exhibit hexagonal plate-like structure. The anisotropy field Ha of the BFTO decreases almost linearly with the increase in Ti concentration, which leads to a shift of the natural resonance peak toward low frequency. Two natural resonance peaks appear, which can be assigned to the double values of the Landé factor g that are found to be ∼2.0 and ∼2.3 in the system and can be essentially attributed to the existence of Fe3+ ions and the exchange coupling effect between Fe3+ and Fe2+ ions, respectively. Such a dual resonance effect contributes a broad magnetic loss peak and thus a high attenuation constant, and leads to a dual reflection loss (RL) peak over the frequency range between 26.5 and 40 GHz. The high attenuation constants are between 350 and 500 at peak position. The optimal RL reaches around −45 dB and the practicable frequency bandwidth is beyond 11 GHz. This suggests that the BFTO powders could be used as microwave absorbing materials with extraordinary properties. PMID:27877595

  3. Exchange coupling controlled ferrite with dual magnetic resonance and broad frequency bandwidth in microwave absorption.

    PubMed

    Jia, Jingguo; Liu, Chuyang; Ma, Ning; Han, Gaorong; Weng, Wenjian; Du, Piyi

    2013-08-01

    Ti-doped barium ferrite powders BaFe12-x Ti x O19 (x = 0, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) were synthesized by the sol-gel method. The phase structure and morphology were analyzed by x-ray diffraction (XRD) and scanning electron microscopy, respectively. The powders were also studied for their magnetic properties and microwave absorption. Results show that the Ti-doped barium ferrites (BFTO) exist in single phase and exhibit hexagonal plate-like structure. The anisotropy field Ha of the BFTO decreases almost linearly with the increase in Ti concentration, which leads to a shift of the natural resonance peak toward low frequency. Two natural resonance peaks appear, which can be assigned to the double values of the Landé factor g that are found to be ∼2.0 and ∼2.3 in the system and can be essentially attributed to the existence of Fe(3+) ions and the exchange coupling effect between Fe(3+) and Fe(2+) ions, respectively. Such a dual resonance effect contributes a broad magnetic loss peak and thus a high attenuation constant, and leads to a dual reflection loss (RL) peak over the frequency range between 26.5 and 40 GHz. The high attenuation constants are between 350 and 500 at peak position. The optimal RL reaches around -45 dB and the practicable frequency bandwidth is beyond 11 GHz. This suggests that the BFTO powders could be used as microwave absorbing materials with extraordinary properties.

  4. Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project Final Technical Report

    SciTech Connect

    Verma, Puneet; Casey, Dan

    2011-03-29

    This report summarizes the work conducted under U.S. Department of Energy (US DOE) contract DE-FC36-04GO14286 by Chevron Technology Ventures (CTV, a division of Chevron U.S.A., Inc.), Hyundai Motor Company (HMC), and UTC Power (UTCP, a United Technologies company) to validate hydrogen (H2) infrastructure technology and fuel cell hybrid vehicles. Chevron established hydrogen filling stations at fleet operator sites using multiple technologies for on-site hydrogen generation, storage, and dispensing. CTV constructed five demonstration stations to support a vehicle fleet of 33 fuel cell passenger vehicles, eight internal combustion engine (ICE) vehicles, three fuel cell transit busses, and eight internal combustion engine shuttle busses. Stations were operated between 2005 and 2010. HMC introduced 33 fuel cell hybrid electric vehicles (FCHEV) in the course of the project. Generation I included 17 vehicles that used UTCP fuel cell power plants and operated at 350 bar. Generation II included 16 vehicles that had upgraded UTC fuel cell power plants and demonstrated options such as the use of super-capacitors and operation at 700 bar. All 33 vehicles used the Hyundai Tucson sports utility vehicle (SUV) platform. Fleet operators demonstrated commercial operation of the vehicles in three climate zones (hot, moderate, and cold) and for various driving patterns. Fleet operators were Southern California Edison (SCE), AC Transit (of Oakland, California), Hyundai America Technical Center Inc. (HATCI), and the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC, in a site agreement with Selfridge Army National Guard Base in Selfridge, Michigan).

  5. Analysis of the control structures for an integrated ethanol processor for proton exchange membrane fuel cell systems

    NASA Astrophysics Data System (ADS)

    Biset, S.; Nieto Deglioumini, L.; Basualdo, M.; Garcia, V. M.; Serra, M.

    The aim of this work is to investigate which would be a good preliminary plantwide control structure for the process of Hydrogen production from bioethanol to be used in a proton exchange membrane (PEM) accounting only steady-state information. The objective is to keep the process under optimal operation point, that is doing energy integration to achieve the maximum efficiency. Ethanol, produced from renewable feedstocks, feeds a fuel processor investigated for steam reforming, followed by high- and low-temperature shift reactors and preferential oxidation, which are coupled to a polymeric fuel cell. Applying steady-state simulation techniques and using thermodynamic models the performance of the complete system with two different control structures have been evaluated for the most typical perturbations. A sensitivity analysis for the key process variables together with the rigorous operability requirements for the fuel cell are taking into account for defining acceptable plantwide control structure. This is the first work showing an alternative control structure applied to this kind of process.

  6. Connective tissue responses to some heavy metals. I. Sodium loaded ion exchange beads as a control: histology and ultrastructure.

    PubMed Central

    Ellender, G.; Ham, K. N.

    1987-01-01

    Ion exchange resin beads (Amberlite IR-120) were implanted into loose connective tissue as the vehicle for cations in both control and experimental studies. Beads were loaded with sodium for control purposes or with the metal of interest for subsequent experimental studies. When single control beads were implanted in the loose connective tissue of the rat pinna, they were well accepted by tissue and permitted rapid healing. The bead implantation initially produced minimal inflammatory disruption and subsequent repair at the bead-tissue interface which rapidly matured leaving no fibro-collagenous capsule. Some minor geometric rearrangement occurred in the alignment of the connective tissue to compensate for the physical presence of the bead. This system provides a valid control for studies of the effects of metal cations on tissue inflammation and repair--free from anionic complications, surface phenomena or systemic interference. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:3620327

  7. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Particulate Matter (PM) Controls

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  8. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Fabric Filter Control Devices

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  9. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Electrostatic Precipitator Control Device

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  10. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Condenser Control Device

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  11. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Thermal Oxidizer Control Device

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  12. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Scrubbers for Gaseous Pollutants Control Devices

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  13. Compliance Assurance Monitoring Technical Guidance Document Appendix A:Volatile Organic Compound (VOC) Controls

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  14. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Scrubbers for Particulate Matter Control Devices

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  15. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Carbon Adsorber Control Device

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  16. TECHNICAL DESIGN NOTE: Digital proportional-integral-derivative velocity controller of a Mössbauer spectrometer

    NASA Astrophysics Data System (ADS)

    Pechousek, J.; Prochazka, R.; Mashlan, M.; Jancik, D.; Frydrych, J.

    2009-01-01

    The digital proportional-integral-derivative (PID) velocity controller used in the Mössbauer spectrometer implemented in field programmable gate array (FPGA) is based on the National Instruments CompactRIO embedded system and LabVIEW graphical programming tools. The system works as a remote system accessible via the Ethernet. The digital controller operates in real-time conditions, and the maximum sampling frequency is approximately 227 kS s-1. The system was tested with standard sample measurements of α-Fe and α-57Fe2O3 on two different electromechanical velocity transducers. The nonlinearities of the velocity scales in the relative form are better than 0.2%. The replacement of the standard analog PID controller by the new system brings the possibility of optimizing the control process more precisely.

  17. 32 CFR 250.9 - Notice to accompany the dissemination of export-controlled technical data.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for items controlled by the International Traffic in Arms Regulations (ITAR), or the Department of... the ITAR is up to 2 years imprisonment, or a fine of $100,000, or both. Under 50 U.S.C., appendix...

  18. 32 CFR 250.9 - Notice to accompany the dissemination of export-controlled technical data.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... for items controlled by the International Traffic in Arms Regulations (ITAR), or the Department of... the ITAR is up to 2 years imprisonment, or a fine of $100,000, or both. Under 50 U.S.C., appendix...

  19. 32 CFR 250.9 - Notice to accompany the dissemination of export-controlled technical data.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for items controlled by the International Traffic in Arms Regulations (ITAR), or the Department of... the ITAR is up to 2 years imprisonment, or a fine of $100,000, or both. Under 50 U.S.C., appendix...

  20. 32 CFR 250.9 - Notice to accompany the dissemination of export-controlled technical data.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... for items controlled by the International Traffic in Arms Regulations (ITAR), or the Department of... the ITAR is up to 2 years imprisonment, or a fine of $100,000, or both. Under 50 U.S.C., appendix...

  1. 32 CFR 250.9 - Notice to accompany the dissemination of export-controlled technical data.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for items controlled by the International Traffic in Arms Regulations (ITAR), or the Department of... the ITAR is up to 2 years imprisonment, or a fine of $100,000, or both. Under 50 U.S.C., appendix...

  2. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Electrified Filter Bed Control Device

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  3. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Wet Electrostatic Precipitator Control Device

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  4. Compliance Assurance Monitoring Technical Guidance Document Appendix A: Control of Other Specific Compounds

    EPA Pesticide Factsheets

    Compliance assurance monitoring is intended to provide a reasonable assurance of compliance with applicable requirements under the Clean Air Act for large emission units that rely on pollution control device equipment to achieve compliance.

  5. Electric- and exchange-field controlled transport through silicene barriers: Conductance gap and near-perfect spin polarization

    SciTech Connect

    Vargiamidis, V.; Vasilopoulos, P.

    2014-12-01

    We study ballistic electron transport through silicene barriers, of width d and height U, in the presence of an exchange field M and a normal electric field E{sub z}. Away from the Dirac point (DP), the spin- and valley-resolved conductances, as functions of U, exhibit resonances while close to it there is a pronounced dip that can be transformed into a transport gap by varying E{sub z}. The charge conductance g{sub c} changes from oscillatory to a monotonically decreasing function of d beyond a critical E{sub z} and this can be used to realize electric-field-controlled switching. Further, the field M splits each resonance of g{sub c} into two spin-resolved peaks. The spin polarization near the DP increases with E{sub z} or M and becomes nearly perfect above certain of their values. Similar results hold for double barriers.

  6. Enhanced proton conductivity of sulfonated poly(p-phenylene-co-aryl ether ketone) proton exchange membranes with controlled microblock structure

    NASA Astrophysics Data System (ADS)

    He, Qingyi; Xu, Tong; Qian, Huidong; Zheng, Jifu; Shi, Ce; Li, Yunqi; Zhang, Suobo

    2015-03-01

    A new series of sulfonated poly(p-phenylene-co-aryl ether ketone)s (s, m, l-SPP-co-PAEKs) microblock polymers containing different hydrophobic units with precisely defined lengths have been prepared via the nickel (0) catalyzed coupling copolymerization and characterized to act as proton exchange membranes. By controlling the length and chemical structure of the hydrophobic units in the copolymers, these novel microblock polymers can exhibit well-developed nanophase morphologies and large length-scale of the ionic channels, resulting in the improvement of the proton conductivity in both the wet and dry state. Moreover, the membrane l-SPP-co-PAEK 1.80 with the largest hydrophobic micro-block length shows high proton conductivity, excellent dimensional stability, low glass-transition temperature (Tg), good oxidative stability and superior cell performance.

  7. Plant carbon-nutrient interactions control CO{sub 2} exchange in Alaskan wet sedge tundra ecosystems

    SciTech Connect

    Johnson, L.C.; Shaver, G.R.; Cades, D.H.; Rastetter, E.; Nadelhoffer, K.; Giblin, A.; Laundre, J.; Stanley, A.

    2000-02-01

    The authors explored the long-term (8-yr) effects of separate field manipulations of temperature and nutrient availability on carbon balance in wet sedge tundra near the Arctic Long Term Ecological Research (LTER) site at Toolik Lake, Alaska. Their goals were (1) to assess the relative importance of chronic warming (with field greenhouses) and increased N and P availability (by fertilization) in controlling gross ecosystem photosynthesis, ecosystem respiration, and ultimately ecosystem C balance; and (2) to attempt to partition ecosystem responses to these treatments between plant and soil contributions. The authors present results of the effects of these manipulations on whole-system CO{sub 2} exchange over seasonal and duel cycles, and on nonrhizosphere soil microbial respiration using in situ soil incubations.

  8. The boot software of the control unit of the near infrared spectrograph of the Euclid space mission: technical specification

    NASA Astrophysics Data System (ADS)

    Gómez-Sáenz-de-Tejada, Jaime; Toledo-Moreo, Rafael; Colodro-Conde, Carlos; Pérez-Lizán, David; Fernández-Conde, Jesús; Sánchez-Prieto, Sebastián.

    2016-07-01

    The Near Infrared Spectrograph and Photometer (NISP) is one of the instruments on board the ESA EUCLID mission. The Boot Software (BSW) is in charge of initialization and communications after a reset occurs at hard- ware level. The Universidad Politecnica de Cartagena and Instituto de Astrofisica de Canarias are responsible of the Instrument Control Unit of the NISP (NI-ICU) in the Euclid Consortium. The NI-ICU BSW is developed by Universidad de Alcaĺa, and its main functions are: communication with the S/C for memory management, self-tests and start of a patchable Application Software (ASW). This paper presents the NI-ICU BSW status of definition and design at the end of the Technical Specification phase.

  9. Electric Power Research Institute: Environmental Control Technology Center. Report to the Steering Committee, February 1996. Final technical report

    SciTech Connect

    1996-02-01

    Operations and maintenance continued this month at the Electric Power Research Institute`s Environmental Control Technology Center. Testing on the 4.0 MW Pilot Wet FGD unit continued this month with the Carbon Injection System and the Trace Element Removal test blocks. With this testing, the mercury measurement (Method 29) studies also continued with impinger capture solutions. The 4.0 MW Spray Dryer Absorber System (Carbon Injection System) was utilized in the TER test configuration this month. The B&W/CHX Heat Exchanger unit is being installed utilizing the Mini Pilot Flue Gas System. The 1.0 MW Cold- Side Selective Catalytic Reduction (SCR) unit remained idle this month in a cold-standby mode. Monthly inspections were conducted for all equipment in cold-standby, as well as for the fire safety systems, and will continue to be conducted by the ECTC Operations and Maintenance staff.

  10. Tracking instrument and control for solar concentrators. Final technical report, October 1979-January 1981

    SciTech Connect

    Gray, J; Kuhlman, J

    1981-01-31

    The tracker uses a single photo sensor, and a rotating aperature to obtain tracking accuracies better than 1.5 mrads (0.1 degs). Peak signal detection is used to eliminate tracking of false sources, i.e., clouds, etc. A prism is employed to obtain an extended field of view (150 degs axially - 360 degs radially). The tracker digitally measures the Suns displacement angle relative to the concentrator axis, and repositions it incrementally. This arrangement permits the use of low cost non-servo motors. The local controller contains microprocessor based electronics, incorporating digital signal processing. A single controller may be time shared by a maximum of sixteen trackers, providing a high performance, cost effective solar tracking system, suitable for both line and point focus concentrators. An installation may have the local controller programmed as a standalone unit or slaved to a central controller. When used with a central controller, dynamic data monitoring and logging is available, together with the ability to change system modes and parameters, as desired.

  11. Ultra-low-volume ground aerosols of technical malathion for the control of Aedes aegypti L

    PubMed Central

    Pant, C. P.; Mount, G. A.; Jatanasen, Sujarti; Mathis, H. L.

    1971-01-01

    The efficacy of malathion aerosols applied from the ground was evaluated for the control of Ae. aegypti. Several techniques for applying the aerosols to an inhabited locality were investigated, and it was found that excellent control of adult mosquitos could be obtained with a dosage of 438 ml/ha. Two treatments carried out 3 days apart enabled the adult mosquito population to be reduced by 99%, and it took about 2 weeks to regain its pretreatment level. Schedules of treatment and strategies to be applied during an epidemic are discussed. PMID:5317014

  12. Waterford SES unit No. 3 control room design review/audit technical evaluation report

    SciTech Connect

    Smith, J.P.

    1981-06-01

    As part of the NRC staff actions following the TMI-2 accident (Item I.D.1, NUREG-0660, Vol. 1, May 1980), it is required that all licensees and applicants for operating licenses conduct a Detailed Control Room Design Review (DCRDR) to identify and correct human factors design deficiencies. Louisiana Power and Light Co. (LP and L) performed a preliminary assessment of the Waterford SES Unit No. 3 control room and submitted its findings to the NRC in a report dated April 15, 1981, for review and evaluation. The Human Factors Engineering Branch (HFEB) performed an interim review of the LP and L preliminary assessment report.

  13. PV batteries and charge controllers: Technical issues, costs, and market trends

    SciTech Connect

    Hammond, R.L.; Turpin, J.F.; Corey, G.P.; Hund, T.D.; Harrington, S.R.

    1997-11-01

    A survey of US system integrators, charge controller manufacturers, and battery manufacturers was conducted in 1996 to determine market and application trends. This survey was sponsored by the USDOE. Results from 21 system integrators show a 1995 PV battery sales of $4.76 million. Using the survey results, a top down market analysis was conducted with a total predicted US battery market of $34.7 million and a world wide market of US $302 million. The survey also indicated that 71% (of dollars) were spent on VRLA and 29% on flooded lead-acid batteries. Eighty percent of charge controllers were ON-OFF, vs. PWM or constant voltage.

  14. Technical report on "BES Early Career. Control Graphene Electronic Structure for Energy Technology"

    SciTech Connect

    Wang, Feng

    2015-07-11

    Graphene, a one-atom thick sheet of carbon, exhibits incredible structural flexibility, electrical transport, and optical responses. And remarkably, the graphene electronic structure can be varied through interlayer coupling, nanoscale patterning, and electrical gating. In this project we made significant contribution to better understand and control physical properties of graphene and other novel two-dimensional layered materials.

  15. Practical optimal flight control system design for helicopter aircraft. Volume 1: Technical Report

    NASA Technical Reports Server (NTRS)

    Hofmann, L. G.; Riedel, S. A.; Mcruer, D.

    1980-01-01

    A method by which modern and classical theory techniques may be integrated in a synergistic fashion and used in the design of practical flight control systems is presented. A general procedure is developed, and several illustrative examples are included. Emphasis is placed not only on the synthesis of the design, but on the assessment of the results as well.

  16. TECHNICAL CHALLENGES INVOLVED IN IMPLEMENTATION OF VOC REACTIVITY-BASED CONTROL OF OZONE

    EPA Science Inventory

    The control of VOC emissions based on their individual contribution to ozone formation has been the subject of intensive discussion and research in the past five years, and has gained a large degree of acceptance in the air pollution regulatory community for certain industrial op...

  17. Review of corrosion causes and corrosion control in a technical facility

    NASA Technical Reports Server (NTRS)

    Charng, T.; Lansing, F.

    1982-01-01

    Causes of corrosion of metals and their alloys are reviewed. The corrosion mechanism is explained by electrochemical reaction theory. The causes and methods of controlling of both physiochemical corrosion and biological corrosion are presented. Factors which influence the rate of corrosion are also discussed.

  18. Flight Evaluation Procedures and Quality Control of Training. Technical Report 68-3.

    ERIC Educational Resources Information Center

    Caro, Paul W., Jr.

    Research at the United States Army Aviation School, Fort Rucker, Alabama, sought to improve the school-wide training quality control system. Investigators studied: 1) the relation between the grades a student received from instructors and those he received from a checkpilot; 2) the effect of checkpilots' prior information about students' progress…

  19. Stores Control. Supervising: Technical Aspects of Supervision. The Choice Series #41. A Self-Learning Opportunity.

    ERIC Educational Resources Information Center

    Austin, David

    This learning unit on stores control is one in the Choice Series, a self-learning development program for supervisors. The purpose of the approximately eight-hour-long unit is to enable the supervisor to design and organize the layout of a store for maximum efficiency, understand the types of documentation associated with the movement of goods…

  20. New technical facilities for equipping power industry plants with automatic control systems

    NASA Astrophysics Data System (ADS)

    Sviderskii, A. G.; Herpel, H.

    2008-10-01

    The specific features of SPPA-T3000, a new instrumentation and control system intended for automation of processes in power engineering, are briefly described. Distinctive features of the system architecture, central to which is using the model of web systems, are singled out.

  1. REPORT TO CONGRESS: ASSESSMENT OF INTERNATIONAL AIR POLLUTION PREVENTION AND CONTROL TECHNOLOGY VOLUME 2. TECHNICAL REPORT

    EPA Science Inventory

    The report gives results of a study that identifies new and innovative air pollution prevention and/or control technologies, of selected industrialized countries, that are not currently used extensively in the U.S. The technologies may be entirely new to the U.S., or they may be ...

  2. An application of indirect model reference adaptive control to a low-power proton exchange membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Yang, Yee-Pien; Liu, Zhao-Wei; Wang, Fu-Cheng

    2008-05-01

    Nonlinearity and the time-varying dynamics of fuel cell systems make it complex to design a controller for improving output performance. This paper introduces an application of a model reference adaptive control to a low-power proton exchange membrane (PEM) fuel cell system, which consists of three main components: a fuel cell stack, an air pump to supply air, and a solenoid valve to adjust hydrogen flow. From the system perspective, the dynamic model of the PEM fuel cell stack can be expressed as a multivariable configuration of two inputs, hydrogen and air-flow rates, and two outputs, cell voltage and current. The corresponding transfer functions can be identified off-line to describe the linearized dynamics with a finite order at a certain operating point, and are written in a discrete-time auto-regressive moving-average model for on-line estimation of parameters. This provides a strategy of regulating the voltage and current of the fuel cell by adaptively adjusting the flow rates of air and hydrogen. Experiments show that the proposed adaptive controller is robust to the variation of fuel cell system dynamics and power request. Additionally, it helps decrease fuel consumption and relieves the DC/DC converter in regulating the fluctuating cell voltage.

  3. Interpolity exchange of basalt tools facilitated via elite control in Hawaiian archaic states.

    PubMed

    Kirch, Patrick V; Mills, Peter R; Lundblad, Steven P; Sinton, John; Kahn, Jennifer G

    2012-01-24

    Ethnohistoric accounts of late precontact Hawaiian archaic states emphasize the independence of chiefly controlled territories (ahupua'a) based on an agricultural, staple economy. However, elite control of unevenly distributed resources, such as high-quality volcanic rock for adze production, may have provided an alternative source of economic power. To test this hypothesis we used nondestructive energy-dispersive X-ray fluorescence (ED-XRF) analysis of 328 lithic artifacts from 36 archaeological features in the Kahikinui district, Maui Island, to geochemically characterize the source groups. This process was followed by a limited sampling using destructive wavelength-dispersive X-ray fluorescence (WD-XRF) analysis to more precisely characterize certain nonlocal source groups. Seventeen geochemical groups were defined, eight of which represent extra-Maui Island sources. Although the majority of stone tools were derived from Maui Island sources (71%), a significant quantity (27%) of tools derived from extraisland sources, including the large Mauna Kea quarry on Hawai'i Island as well as quarries on O'ahu, Moloka'i, and Lāna'i islands. Importantly, tools quarried from extralocal sources are found in the highest frequency in elite residential features and in ritual contexts. These results suggest a significant role for a wealth economy based on the control and distribution of nonagricultural goods and resources during the rise of the Hawaiian archaic states.

  4. Interpolity exchange of basalt tools facilitated via elite control in Hawaiian archaic states

    PubMed Central

    Kirch, Patrick V.; Mills, Peter R.; Lundblad, Steven P.; Sinton, John; Kahn, Jennifer G.

    2012-01-01

    Ethnohistoric accounts of late precontact Hawaiian archaic states emphasize the independence of chiefly controlled territories (ahupua‘a) based on an agricultural, staple economy. However, elite control of unevenly distributed resources, such as high-quality volcanic rock for adze production, may have provided an alternative source of economic power. To test this hypothesis we used nondestructive energy-dispersive X-ray fluorescence (ED-XRF) analysis of 328 lithic artifacts from 36 archaeological features in the Kahikinui district, Maui Island, to geochemically characterize the source groups. This process was followed by a limited sampling using destructive wavelength-dispersive X-ray fluorescence (WD-XRF) analysis to more precisely characterize certain nonlocal source groups. Seventeen geochemical groups were defined, eight of which represent extra-Maui Island sources. Although the majority of stone tools were derived from Maui Island sources (71%), a significant quantity (27%) of tools derived from extraisland sources, including the large Mauna Kea quarry on Hawai‘i Island as well as quarries on O‘ahu, Moloka‘i, and Lāna‘i islands. Importantly, tools quarried from extralocal sources are found in the highest frequency in elite residential features and in ritual contexts. These results suggest a significant role for a wealth economy based on the control and distribution of nonagricultural goods and resources during the rise of the Hawaiian archaic states. PMID:22203984

  5. The use of training and technical assistance to drive and improve performance of California's Tobacco Control Program.

    PubMed

    Roeseler, April; Hagaman, Tonia; Kurtz, Caroline

    2011-11-01

    The California Department of Public Health, California Tobacco Control Program uses a social norm-change strategy to reduce the uptake and continued use of tobacco products. The statewide media campaign frames the message, community-level projects implement advocacy campaigns, and statewide-funded projects build the capacity of community-level projects. The California Tobacco Control Program's technical assistance (TA) system has evolved over time because of changing needs, evaluation findings, and budget considerations. However, TA services continue to strategically align with four statewide policy priorities: to eliminate secondhand smoke exposure, to counter protobacco influences, to reduce the availability of tobacco, and to promote cessation services. TA is the engine powering social change across California by playing a key role in the uptake of a single policy to facilitating the adoption of hundreds of tobacco control policies statewide. The inclusion of expert and peer-to-peer TA models broadly disseminates both evidence-based and tacit community-based knowledge. Comprehensive TA also levels the playing field for organizations and communities to effectively implement policy interventions. Together these approaches accelerate change throughout California communities.

  6. Advanced Instrumentation, Information, and Control Systems Technologies Technical Program Plan for 2014

    SciTech Connect

    Hallbert, Bruce; Thomas, Ken

    2014-07-01

    The Advanced Instrumentation, Information, and Control (II&C) Systems Technologies Pathway conducts targeted research and development (R&D) to address aging and reliability concerns with the legacy instrumentation and control and related information systems of the U.S. operating light water reactor (LWR) fleet. This work involves two major goals: (1) to ensure that legacy analog II&C systems are not life-limiting issues for the LWR fleet, and (2) to implement digital II&C technology in a manner that enables broad innovation and business improvement in the nuclear power plant operating model. Resolving long-term operational concerns with the II&C systems contributes to the long-term sustainability of the LWR fleet, which is vital to the nation's energy and environmental security.

  7. Rapid regulatory control of plant cell expansion and wall relaxation. Annual technical progress report

    SciTech Connect

    Cosgrove, D.J.

    1991-08-14

    The aim of this project is to elucidate the biophysical and cellular mechanisms that control plant cell expansion. At present we are attempting to characterize the kinetics of the system(s) responsible for regulatory and compensatory behavior of growing cells and tissues. This work is significantly because it indicates that biochemical loosening and biophysical stress relaxation of the wall are part of a feedback loop controlling growth. This report briefly summarizes the efforts and results of the past 12 months. In large part, we have been trying to analyze the nature of growth rate ``noise,`` i.e. spontaneous and often erratic variations in growth rate. We are obtaining evidence that such ``noise`` is not random, but rather reveals an underlying growth mechanism with complex dynamics.

  8. Genetic control of nitrate assimilation in Klebsiella oxytoca. Final technical report

    SciTech Connect

    Stewart, Valley J.

    2001-04-01

    Some microorganisms can use nitrate as the sole source of nitrogen for biosynthesis. This project focused on the bacterium Klebsiella oxytoca, an enterobacterium found in soil and water. Mutagenesis and molecular cloning identified the nasFEDCBA operon encoding enzymes for the uptake and reduction of nitrate and nitrite to ammonium, and the adjacent nasR regulatory gene. Analysis of nasF operon expression revealed that transcription is activated by the Ntr (general nitrogen regulation ) system in response to nitrogen limitation. Transcription antitermination control in response to nitrate and nitrite is mediated by the NasR protein. Additional work established that the NasR protein is an RNA-binding protein that interacts with nasF operon leader RNA to control transcription readthrough.

  9. Emissions and fuel economy effects of vehicle exhaust emission control device (revision). Technical report

    SciTech Connect

    Johnson, H.

    1998-10-01

    This report describes testing by EPA of the Vehicle Exhaust Emission Control Device (VEECD) retrofit device under Section 32918 of Title 49 U.S.C. Retrofit Devices (RD). The VEECD is described by the developer in the international patent application as an embodiment of air bleed principle. It is intended to be retrofitted to vehicles produced without any, or with earlier-technology emission control systems. The developer claims (RD Application Appendix A) that the valve significantly reduces CO and HC emissions without substantially increasing CO{sub 2} or NOx emissions. Incidental city fuel economy enhancement was also claimed. Non-FTP test data obtained for 1986/87 European vehicles from two laboratories in the UK was submitted. This data (Appendix B) was analyzed using the t-test for the difference of constant speed data (30/60/85MPH) at 95% confidence level.

  10. Technical Standards for Command and Control Information Systems (CCISs) and Information Technology

    DTIC Science & Technology

    1994-02-01

    transport sensor image acquisition Image compression and decompression Iimage presentation Source: DIS 12087. 1993. In a recent liaison to SC21, SC24 noted...Distributed Queue Dual Bus (DODS) Media Access Control (MAC) ISCVIEC 6602-7 LANs. Part 7: Slotted Ring Access Method and Physical Layer Specification...1.5, 6, and 12 MHz, respectively. The standard recommends the use of a single-cable system with a head-end frequency translator. Dual cable is also

  11. Control system failure monitoring using generalized parity relations. M.S. Thesis Interim Technical Report

    NASA Technical Reports Server (NTRS)

    Vanschalkwyk, Christiaan Mauritz

    1991-01-01

    Many applications require that a control system must be tolerant to the failure of its components. This is especially true for large space-based systems that must work unattended and with long periods between maintenance. Fault tolerance can be obtained by detecting the failure of the control system component, determining which component has failed, and reconfiguring the system so that the failed component is isolated from the controller. Component failure detection experiments that were conducted on an experimental space structure, the NASA Langley Mini-Mast are presented. Two methodologies for failure detection and isolation (FDI) exist that do not require the specification of failure modes and are applicable to both actuators and sensors. These methods are known as the Failure Detection Filter and the method of Generalized Parity Relations. The latter method was applied to three different sensor types on the Mini-Mast. Failures were simulated in input-output data that were recorded during operation of the Mini-Mast. Both single and double sensor parity relations were tested and the effect of several design parameters on the performance of these relations is discussed. The detection of actuator failures is also treated. It is shown that in all the cases it is possible to identify the parity relations directly from input-output data. Frequency domain analysis is used to explain the behavior of the parity relations.

  12. Surfactant control of gas transfer velocity along an offshore coastal transect: results from a laboratory gas exchange tank

    NASA Astrophysics Data System (ADS)

    Pereira, R.; Schneider-Zapp, K.; Upstill-Goddard, R. C.

    2016-07-01

    Understanding the physical and biogeochemical controls of air-sea gas exchange is necessary for establishing biogeochemical models for predicting regional- and global-scale trace gas fluxes and feedbacks. To this end we report the results of experiments designed to constrain the effect of surfactants in the sea surface microlayer (SML) on the gas transfer velocity (kw; cm h-1), seasonally (2012-2013) along a 20 km coastal transect (North East UK). We measured total surfactant activity (SA), chromophoric dissolved organic matter (CDOM) and chlorophyll a (Chl a) in the SML and in sub-surface water (SSW) and we evaluated corresponding kw values using a custom-designed air-sea gas exchange tank. Temporal SA variability exceeded its spatial variability. Overall, SA varied 5-fold between all samples (0.08 to 0.38 mg L-1 T-X-100), being highest in the SML during summer. SML SA enrichment factors (EFs) relative to SSW were ˜ 1.0 to 1.9, except for two values (0.75; 0.89: February 2013). The range in corresponding k660 (kw for CO2 in seawater at 20 °C) was 6.8 to 22.0 cm h-1. The film factor R660 (the ratio of k660 for seawater to k660 for "clean", i.e. surfactant-free, laboratory water) was strongly correlated with SML SA (r ≥ 0.70, p ≤ 0.002, each n = 16). High SML SA typically corresponded to k660 suppressions ˜ 14 to 51 % relative to clean laboratory water, highlighting strong spatiotemporal gradients in gas exchange due to varying surfactant in these coastal waters. Such variability should be taken account of when evaluating marine trace gas sources and sinks. Total CDOM absorbance (250 to 450 nm), the CDOM spectral slope ratio (SR = S275 - 295/S350 - 400), the 250 : 365 nm CDOM absorption ratio (E2 : E3), and Chl a all indicated spatial and temporal signals in the quantity and composition of organic matter in the SML and SSW. This prompts us to hypothesise that spatiotemporal variation in R660 and its relationship with SA is a consequence of compositional

  13. Technical cooperation on nuclear security between the United States and China : review of the past and opportunities for the future.

    SciTech Connect

    Pregenzer, Arian Leigh

    2011-12-01

    The United States and China are committed to cooperation to address the challenges of the next century. Technical cooperation, building on a long tradition of technical exchange between the two countries, can play an important role. This paper focuses on technical cooperation between the United States and China in the areas of nonproliferation, arms control and other nuclear security topics. It reviews cooperation during the 1990s on nonproliferation and arms control under the U.S.-China Arms Control Exchange, discusses examples of ongoing activities under the Peaceful Uses of Technology Agreement to enhance security of nuclear and radiological material, and suggests opportunities for expanding technical cooperation between the defense nuclear laboratories of both countries to address a broader range of nuclear security topics.

  14. Collaborative distributed sensor management and information exchange flow control for multitarget tracking using Markov decision processes

    NASA Astrophysics Data System (ADS)

    Akselrod, Dimitry; Kirubarajan, T.

    2008-04-01

    In this paper, we consider the problem of collaborative management of uninhabited aerial vehicles (UAVs) for multitarget tracking. In addition to providing a solution to the problem of controlling individual UAVs, we present a method for controlling the information flow among them. The latter provides a solution to one of the main problems in decentralized tracking, namely, distributed information transfer and fusion among the participating platforms. The problem of decentralized cooperative control considered in this paper is an optimization of the information obtained by a number of UAVs, carrying out surveillance over a region, which includes a number of confirmed and suspected moving targets with the goal to track confirmed targets and detects new targets in the area. Each UAV has to decide on the most optimal path with the objective to track as many targets as possible, maximizing the information obtained during its operation with the maximum possible accuracy at the lowest possible cost. Limited communication between UAVs and uncertainty in the information obtained by each UAV regarding the location of the ground targets are addressed in the problem formulation. In order to handle these issues, the problem is presented as an operation of a group of decision makers. Markov Decision Processes (MDPs) are incorporated into the solution. A decision mechanism for collaborative distributed data fusion provides each UAV with the required data for the fusion process while substantially reducing redundancy in the information flow in the overall system. We consider a distributed data fusion system consisting of UAVs that are decentralized, heterogenous, and potentially unreliable. Simulation results are presented on a representative multisensor-multitarget tracking problem.

  15. Digital Control of Exchange Interaction in a Spin-based Silicon Quantum Computer

    DTIC Science & Technology

    2013-05-19

    the  current  enhancement,  is  required for the formation of coherent Majorana  bound   states .       Figure  F.4:  I/V  characteristic  of  a  JJ...Workshop “Majorana Fermion Zero Modes in Solid- State Systems: Experiment and Theory”, Kalvi Institute of Theoretical Physics, UCSB, December 2-14...modulation-doped and enhancement-mode Si/SiGe heterostructures,” 2011 PCCM Symposium: Quantum Control of Solid State Systems, Princeton, NJ, Nov. 3 – 5

  16. Effect of mobile phone reminder messages on adherence of stent removal or exchange in patients with benign pancreaticobiliary diseases: a prospectively randomized, controlled study.

    PubMed

    Gu, Yong; Wang, Limei; Zhao, Lina; Liu, Zhiguo; Luo, Hui; Tao, Qin; Zhang, Rongchun; He, Shuixiang; Wang, Xiangping; Huang, Rui; Zhang, Linhui; Pan, Yanglin; Guo, Xuegang

    2016-08-26

    Plastic and covered metal stents need to be removed or exchanged within appropriate time in case of undesirable complications. However, it is not uncommon that patients do not follow the recommendation for further stent management after Endoscopic Retrograde Cholangiopancreatography (ERCP). The effect of short message service (SMS) intervention monthly on the stent removal/exchange adherence in patients after ERCP is unknown at this time. A prospective, randomized controlled study was conducted. After receiving regular instructions, patients were randomly assigned to receive SMS reminding monthly (SMS group) for stent removal/exchange or not (control group). The primary outcome was stent removal/exchange adherence within appropriate time (4 months for plastic stent or 7 months for covered stent). Multivariate analysis was performed to assess factors associated with stent removal/exchange adherence within appropriate time. Intention-to-treat analysis was used. A total of 48 patients were randomized, 23 to the SMS group and 25 to the control. Adherence to stent removal/exchange was reported in 78.2 % (18/23) of patients receiving the SMS intervention compared with 40 % (10/25) in the control group (RR 1.98, 95 % CI 1.16-3.31; p = 0 · 010). Among patients with plastic stent insertion, the median interval time from stent implantation to stent removal/exchange were 90 days in the SMS group and 136 days in the control respectively (HR 0.36, 95 % CI 0.16-0.84, p = 0.018). No difference was found between the two groups regarding late-stage stent-related complications. The rate of recurrent abdominal pain tended to be lower in SMS group without significant difference (8.7 vs 28 %, p = 0.144). Multivariate logistic regression analyses revealed that SMS reminding was the only factor associated with adherence of stent removal/exchange (OR 6.73, 95 % CI 1.64-27.54, p = 0.008). This first effectiveness trial demonstrated that SMS reminding monthly

  17. Ion-exchange controls the kinetics of deswelling of polyelectrolyte microgels in solutions of oppositely charged surfactant.

    PubMed

    Nilsson, Peter; Hansson, Per

    2005-12-22

    The kinetics of deswelling of sodium polyacrylate microgels (radius 30-140 microm) in aqueous solutions of dodecyltrimethylammonium bromide is investigated by means of micropipet-assisted light microscopy. The purpose of the study is to test a recent model (J. Phys. Chem. B 2003, 107, 9203) proposing that the rate of the volume change is controlled by the transport of surfactant from the solution to the gel core (ion exchange) via the surfactant-rich surface phase appearing in the gel during the volume transition. Equilibrium swelling characteristics of the gel network in surfactant-free solutions and with various amounts of surfactant present are presented and discussed with reference to related systems. A relationship between gel volume and degree of surfactant binding is determined and used in theoretical predictions of the deswelling kinetics. Experimental data for single gel beads observed during deswelling under conditions of forced convection are presented and compared with model calculations. It is demonstrated that the dependences of the kinetics on initial gel size, the surfactant concentration in the solution, and the liquid flow rate are well accounted for by the model. It is concluded that the deswelling rates of the studied gels are strongly influenced by the mass transport of surfactant between gel and solution (stagnant layer diffusion), but only to a minor extent by the transport through the surface phase. The results indicate that, during the volume transition, swelling equilibrium (network relaxation/transport of water) is established on a relatively short time scale and, therefore, can be treated as independent of the ion-exchange kinetics. Theoretical aspects of the kinetics and mechanisms of surfactant transport through the surface phase are discussed.

  18. Use of water exchange information to improve chemical control of eurasian watermilfoil in Pacific Northwest rivers. Final report

    SciTech Connect

    Getsinger, K.D.; Sisneros, D.; Tumer, E.G.

    1993-01-01

    The submersed plant Eurasian watermilfoil (Myriophyllum spicatum L.), continues to adversely impact areas in the high water exchange environment of the Columbia River system. Studies designed to characterize water movement and to evaluate a slow release matrix device (SRMD) for improving the chemical control of that target plant were conducted in the Pend Oreille and Columbia Rivers, Washington, in August 1990. A series of rhodamine WT dye treatments were applied (using conventional, liquid application techniques) to 4-ha plots representing milfoil-dominated riverine and cove sites to estimate potential herbicide contact time. In addition, dye-impregnated SRMDs were deployed in 0.4-ha plots and evaluated for their potential as slow-release herbicide carriers. Dye dissipation data were used to calculate water-exchange half-lives in plots treated with conventional application techniques. Mean half-lives ranged from 8.8 to 12.2 hr in riverine plots, to 36.3 hr in a plot situated in a protected embayment. Half-lives from these 4-ha plots were two to four times longer than half-lives measured in smaller plots (0.4 ha) from previous dye studies conducted in similar locations. In most cases, dye release rates from SRMDs provided water concentrations near the target level of 10 micrograms/L through 7 days after deployment (DAD). Dye concentrations peaked at 105 to 130 micrograms/L at 2 DAD in Plot I (main channel plot) and 4.5 to 82 micrograms/L at I DAD in Plot 2 (side channel plot).

  19. A Randomised Controlled Trial of Ion-Exchange Water Softeners for the Treatment of Eczema in Children

    PubMed Central

    Thomas, Kim S.; Dean, Tara; O'Leary, Caroline; Sach, Tracey H.; Koller, Karin; Frost, Anthony; Williams, Hywel C.

    2011-01-01

    Background Epidemiological studies and anecdotal reports suggest a possible link between household use of hard water and atopic eczema. We sought to test whether installation of an ion-exchange water softener in the home can improve eczema in children. Methods and Findings This was an observer-blind randomised trial involving 336 children (aged 6 months to 16 years) with moderate/severe atopic eczema. All lived in hard water areas (≥200 mg/l calcium carbonate). Participants were randomised to either installation of an ion-exchange water softener plus usual eczema care, or usual eczema care alone. The primary outcome was change in eczema severity (Six Area Six Sign Atopic Dermatitis Score, SASSAD) at 12 weeks, measured by research nurses who were blinded to treatment allocation. Analysis was based on the intent-to-treat population. Eczema severity improved for both groups during the trial. The mean change in SASSAD at 12 weeks was −5.0 (20% improvement) for the water softener group and −5.7 (22% improvement) for the usual care group (mean difference 0.66, 95% confidence interval −1.37 to 2.69, p = 0.53). No between-group differences were noted in the use of topical corticosteroids or calcineurin inhibitors. Conclusions Water softeners provided no additional benefit to usual care in this study population. Small but statistically significant differences were found in some secondary outcomes as reported by parents, but it is likely that such improvements were the result of response bias, since participants were aware of their treatment allocation. A detailed report for this trial is also available at http://www.hta.ac.uk. Trial registration Current Controlled Trials ISRCTN71423189 Please see later in the article for the Editors' Summary PMID:21358807

  20. Photosynthesis Decrease and Stomatal Control of Gas Exchange in Abies alba Mill. in Response to Vapor Pressure Difference

    PubMed Central

    Guehl, Jean-Marc; Aussenac, Gilbert

    1987-01-01

    The responses of steady state CO2 assimilation rate (A), transpiration rate (E), and stomatal conductance (gs) to changes in leaf-to-air vapor pressure difference (ΔW) were examined on different dates in shoots from Abies alba trees growing outside. In Ecouves, a provenance representative of wet oceanic conditions in Northern France, both A and gs decreased when ΔW was increased from 4.6 to 14.5 Pa KPa−1. In Nebias, which represented the dry end of the natural range of A. alba in southern France, A and gs decreased only after reaching peak levels at 9.0 and 7.0 Pa KPa−1, respectively. The representation of the data in assimilation rate (A) versus intercellular CO2 partial pressure (Ci) graphs allowed us to determine how stomata and mesophyll photosynthesis interacted when ΔW was increased. Changes in A were primarily due to alterations in mesophyll photosynthesis. At high ΔW, and especially in Ecouves when soil water deficit prevailed, A declined, while Ci remained approximately constant, which may be interpreted as an adjustment of gs to changes in mesophyll photosynthesis. Such a stomatal control of gas exchange appeared as an alternative to the classical feedforward interpretation of E versus ΔW responses with a peak rate of E. The gas exchange response to ΔW was also characterized by considerable deviations from the optimization theory of IR Cowan and GD Farquhar (1977 Symp Soc Exp Biol 31: 471-505). PMID:16665243

  1. Seasonal patterns and control of gas exchange in local populations of the Mediterranean evergreen shrub Pistacia lentiscus L.

    NASA Astrophysics Data System (ADS)

    Flexas, Jaume; Gulías, Javier; Jonasson, Sven; Medrano, Hipólito; Mus, Mauricio

    2001-02-01

    We examined temporal and spatial variations in net photosynthesis, stomatal conductance, intrinsic water-use efficiency, sub-stomatal CO 2 concentration, apparent carboxylation efficiency and chlorophyll fluorescence in the Mediterranean shrub Pistacia lentiscus. The study was done at the extremes of a precipitation and temperature gradient on the coast and in the mountains of Mallorca, Spain, with gas exchange measurements at different times of the year, and combined measurements of gas exchange and chlorophyll fluorescence in a controlled experiment. The objectives were to relate annual variation in photosynthetic functions to environmentally induced constraints and to quantify to which extent local differences in climate can affect photosynthesis in shrub populations. In the mountain population, net photosynthesis peaked in spring and autumn, when water was abundant and temperature was moderately high. It was reduced in winter paralleling reduced carboxylation efficiency. Photosynthesis was at the annual minimum in summer at both sites due to drought-induced stomata closure combined with impaired function of the Calvin cycle. The coastal population maintained high photosynthesis in mid winter but had a pronounced decline in spring, and the summer decline lasted longer than in the mountains. Integrated over the seasons, net photosynthesis was about 25 % lower in the coastal than in the mountain population, in spite of maintained high mid winter photosynthesis. Hence, the reduction at the coast was mainly due to early onset of drought in spring and a long period of summer drought, showing that local climatic differences can cause pronounced spatial differences in plant carbon balance. As a consequence, similar differences probably also occur as a function of year-to-year variability of precipitation patterns and temperatures.

  2. A randomised controlled trial of ion-exchange water softeners for the treatment of eczema in children.

    PubMed

    Thomas, Kim S; Dean, Tara; O'Leary, Caroline; Sach, Tracey H; Koller, Karin; Frost, Anthony; Williams, Hywel C

    2011-02-15

    Epidemiological studies and anecdotal reports suggest a possible link between household use of hard water and atopic eczema. We sought to test whether installation of an ion-exchange water softener in the home can improve eczema in children. This was an observer-blind randomised trial involving 336 children (aged 6 months to 16 years) with moderate/severe atopic eczema. All lived in hard water areas (≥200 mg/l calcium carbonate). Participants were randomised to either installation of an ion-exchange water softener plus usual eczema care, or usual eczema care alone. The primary outcome was change in eczema severity (Six Area Six Sign Atopic Dermatitis Score, SASSAD) at 12 weeks, measured by research nurses who were blinded to treatment allocation. Analysis was based on the intent-to-treat population. Eczema severity improved for both groups during the trial. The mean change in SASSAD at 12 weeks was -5.0 (20% improvement) for the water softener group and -5.7 (22% improvement) for the usual care group (mean difference 0.66, 95% confidence interval -1.37 to 2.69, p = 0.53). No between-group differences were noted in the use of topical corticosteroids or calcineurin inhibitors. Water softeners provided no additional benefit to usual care in this study population. Small but statistically significant differences were found in some secondary outcomes as reported by parents, but it is likely that such improvements were the result of response bias, since participants were aware of their treatment allocation. A detailed report for this trial is also available at http://www.hta.ac.uk. Current Controlled Trials ISRCTN71423189 Please see later in the article for the Editors' Summary.

  3. Advanced emissions control development program. Quarterly technical progress report {number_sign}4, July 1--September 30, 1995

    SciTech Connect

    Farthing, G.A.

    1995-12-31

    Babcock and Wilcox (B and W) is conducting a five-year project aimed at the development of practical, cost-effective strategies for reducing the emissions of hazardous air pollutants (commonly called air toxics) from coal-fired electric utility plants. The need for air toxic emissions controls will likely arise as the US Environmental Protection Agency proceeds with implementation of Title III of the Clean Air Act Amendments of 1990. Data generated during the program will provide utilities with the technical and economic information necessary to reliably evaluate various air toxics emissions compliance options such as fuel switching, coal cleaning, and flue gas treatment. The development work is being carried out using B and W`s new Clean Environment Development Facility (CEDF) wherein air toxics emissions control strategies can be developed under controlled conditions, and with proven predictability to commercial systems. Tests conducted in the CEDF will provide high quality, repeatable, comparable data over a wide range of coal properties, operating conditions, and emissions control systems. The specific objectives of the project are to: (1) measure and understand the production and partitioning of air toxics species for a variety of steam coals, (2) optimize the air toxics removal performance of conventional flue gas cleanup systems (ESPs, baghouses, scrubbers), (3) develop advanced air toxics emissions control concepts, (4) develop and validate air toxics emissions measurement and monitoring techniques, and (5) establish a comprehensive, self-consistent air toxics data library. Development work is currently concentrated on the capture of mercury, fine particulate, and a variety of inorganic species such as the acid gases (hydrogen chloride, hydrogen fluoride, etc.).

  4. Hanford Waste Vitrification Plant technical background document for best available radionuclide control technology demonstration

    SciTech Connect

    Carpenter, A.B.; Skone, S.S.; Rodenhizer, D.G.; Marusich, M.V. )

    1990-10-01

    This report provides the background documentation to support applications for approval to construct and operate new radionuclide emission sources at the Hanford Waste Vitrification Plant (HWVP) near Richland, Washington. The HWVP is required to obtain permits under federal and state statutes for atmospheric discharges of radionuclides. Since these permits must be issued prior to construction of the facility, draft permit applications are being prepared, as well as documentation to support these permits. This report addresses the applicable requirements and demonstrates that the preferred design meets energy, environmental, and economic criteria for Best Available Radionuclide Control Technology (BARCT) at HWVP. 22 refs., 11 figs., 25 tabs.

  5. Robotic weld overlay coatings for erosion control. Quarterly technical progress report, January 1993--March 1993

    SciTech Connect

    Levin, B.F.; Dupont, J.N.; Marder, A.R.

    1993-04-18

    Twelve weld overlay hardfacing alloys have been selected for preliminary erosion testing based on a literature review These alloys have been separated into three major groups: (1) Cobalt containing alloys, (2) Nickel-base alloys, (3) Iron base alloys. These alloys are being applied to carbon steel substrates and will undergo preliminary erosion testing to identify candidates weld overlay alloys for erosion control in CFB boilers. The candidate alloys selected from the preliminary erosion tests will then undergo more detailed evaluations in future research.

  6. Technical Standards for the ATCCIS (Army Tactical Command and Control Information System) Architecture

    DTIC Science & Technology

    1988-09-01

    CLNP) apply to each of the four LAN options. The X.25 PLP in ISO 8208 or 8878 in Layer 3 and the High-Level Data Link Control (HDLC) in Layer 2 are...3309 ISO 8208 ISO 8073 V.35 ISO 4335 ISO 8878 V.36 IS07478 DIS 2110 IS07776 ISO 2593 ISO 7809 DIS 4902 IS08471 O 8885 Permanent Access to PSDN: End...System X.21 ISO 3309 ISO 8208 ISO 8073 DIS 490 IS0 4335 ISO 8878 ISO 7478 X.25 ISO 7776 ISO 7809 ISO 8471 IS0 8885 X.25 PSDN X.25 X.25 X.25 Permanent

  7. A Survey of Technical Standards for Command and Control Information Systems

    DTIC Science & Technology

    1991-09-01

    calls for extended control field (two octets) with Options 10 and 14 • U- frame is extended (two octets) [3] ANSI X3.66-1979 (ADCCP) * Opt 14 cals for 32...Addresses security through use of UI- frames 61 0 and Release ANSI X3.66-1979 (ADCCP) TRI-TAC ICD 16 Frame Transfer ISO 4335/7809 * Uses all 3 types of...Unclassified Unclassified Unclassified SAR NSN 740.01-230-5500 Stmndad Form 298 (Rev. 2-89) Prescribed by ANSI Std Z39-18 298-102 UNCLASSIFIED IDA PAPER P

  8. 77 FR 42176 - Technical Amendment to Rules for the Temporary Registration of Municipal Advisors

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-18

    ... Municipal Advisors AGENCY: Securities and Exchange Commission. ACTION: Final rule; technical amendment. SUMMARY: The Securities and Exchange Commission (``Commission'') is making a technical amendment to rules... From the Federal Register Online via the Government Publishing Office ] SECURITIES AND...

  9. Dual drug load and release behavior on ion-exchange fiber: influencing factors and prediction method for precise control of the loading amount.

    PubMed

    Yuan, Jing; Gao, Yanan; Liu, Tiaotiao; Wang, Xinyu; Liu, Hongzhuo; Li, Sanming

    2015-01-01

    Ion-exchange fiber undergoes a stoichiometric exchange reaction and has large exchange capability, which makes it a promising candidate as a multiple drug carrier. Because combinatorial effects can act synergistically, additively or antagonistically depending on the ratio of the agents being combined, the objective of this study was to learn the dual drug loading of ion-exchange fiber and develop a mathematical method for precisely control of the loading amount. Atenolol and Gatifloxacin, with different loading behaviors into strong cationic ion-exchange fiber ZB-1, were used to build a representative of dual loading. Not suitable pH value of drug solutions could make simultaneous loading fail, while the change of drug solution volume hardly affected the equilibrium. Ion-exchange groups occupied by the drug which owned lower affinity to fiber could be grabbed by the higher affinity drug, indicating the existence of competition between drugs. Thermodynamic model was introduced to guide the loading prediction and a favorable relevance had been shown between determined and predicted data. The release behaviors of each drug from dual drug-fiber complex were similar to those from single drug-fiber complexes.

  10. Technical advance: stringent control of transgene expression in Arabidopsis thaliana using the Top10 promoter system

    NASA Technical Reports Server (NTRS)

    Love, J.; Scott, A. C.; Thompson, W. F.; Brown, C. S. (Principal Investigator)

    2000-01-01

    We show that the tightly regulated tetracycline-sensitive Top10 promoter system (Weinmann et al. Plant J. 1994, 5, 559-569) is functional in Arabidopsis thaliana. A pure breeding A. thaliana line (JL-tTA/8) was generated which expressed a chimeric fusion of the tetracycline repressor and the activation domain of Herpes simplex virus (tTA), from a single transgenic locus. Plants from this line were crossed with transgenics carrying the ER-targeted green fluorescent protein coding sequence (mGFP5) under control of the Top10 promoter sequence. Progeny from this cross displayed ER-targeted GFP fluorescence throughout the plant, indicating that the tTA-Top10 promoter interaction was functional in A. thaliana. GFP expression was repressed by 100 ng ml-1 tetracycline, an order of magnitude lower than the concentration used previously to repress expression in Nicotiana tabacum. Moreover, the level of GFP expression was controlled by varying the concentration of tetracycline in the medium, allowing a titred regulation of transgenic activity that was previously unavailable in A. thaliana. The kinetics of GFP activity were determined following de-repression of the Top10:mGFP5 transgene, with a visible ER-targeted GFP signal appearing from 24 to 48 h after de-repression.

  11. TECHNICAL PEER REVIEW REPORT - YUCCA MOUNTAIN: WASTE PACKAGE CLOSURE CONTROL SYSTEM

    SciTech Connect

    NA

    2005-10-25

    The objective of the Waste Package Closure System (WPCS) project is to assist in the disposal of spent nuclear fuel (SNF) and associated high-level wastes (HLW) at the Yucca Mountain site in Nevada. Materials will be transferred from the casks into a waste package (WP), sealed, and placed into the underground facility. The SNF/HLW transfer and closure operations will be performed in an aboveground facility. The objective of the Control System is to bring together major components of the entire WPCS ensuring that unit operations correctly receive, and respond to, commands and requests for data. Integrated control systems will be provided to ensure that all operations can be performed remotely. Maintenance on equipment may be done using hands-on or remote methods, depending on complexity, exposure, and ease of access. Operating parameters and nondestructive examination results will be collected and stored as permanent electronic records. Minor weld repairs must be performed within the closure cell if the welds do not meet the inspection acceptance requirements. Any WP with extensive weld defects that require lids to be removed will be moved to the remediation facility for repair.

  12. Technical advance: stringent control of transgene expression in Arabidopsis thaliana using the Top10 promoter system

    NASA Technical Reports Server (NTRS)

    Love, J.; Scott, A. C.; Thompson, W. F.; Brown, C. S. (Principal Investigator)

    2000-01-01

    We show that the tightly regulated tetracycline-sensitive Top10 promoter system (Weinmann et al. Plant J. 1994, 5, 559-569) is functional in Arabidopsis thaliana. A pure breeding A. thaliana line (JL-tTA/8) was generated which expressed a chimeric fusion of the tetracycline repressor and the activation domain of Herpes simplex virus (tTA), from a single transgenic locus. Plants from this line were crossed with transgenics carrying the ER-targeted green fluorescent protein coding sequence (mGFP5) under control of the Top10 promoter sequence. Progeny from this cross displayed ER-targeted GFP fluorescence throughout the plant, indicating that the tTA-Top10 promoter interaction was functional in A. thaliana. GFP expression was repressed by 100 ng ml-1 tetracycline, an order of magnitude lower than the concentration used previously to repress expression in Nicotiana tabacum. Moreover, the level of GFP expression was controlled by varying the concentration of tetracycline in the medium, allowing a titred regulation of transgenic activity that was previously unavailable in A. thaliana. The kinetics of GFP activity were determined following de-repression of the Top10:mGFP5 transgene, with a visible ER-targeted GFP signal appearing from 24 to 48 h after de-repression.

  13. Technical aspects of screen-film radiography, film processing, and quality control.

    PubMed

    Gray, J E

    1997-01-01

    The broad goal of quality control (QC) of screen-film radiography and film processing is to provide radiographs of consistent, high quality. Achievement of this goal requires attention to several areas, including QC of the screen-film system and photographic processor, acceptance testing of all components, and skill in analysis of film artifacts to "diagnose" the processor problems causing the aberrations. Methods to reduce waste, recycle by-products, and reuse resources such as silver are also part of the QC process. To optimize the photographic process, one should use the film, chemical solutions, processor, and screens and cassettes produced by one manufacturer or the combination recommended by the film manufacturer. Important variables in film processing (eg, density, density difference, and base plus fog) are recorded on control charts, which plot the variables as a function of time and allow easy analysis of changes in operating levels. Many variables can affect any component in the screen-film imaging system; problems caused by manufacturing batch-to-batch variation, which is perhaps the most pervasive variable, can be lessened by purchasing film, screens, and cassettes in large batches and of the same batch and by purchasing photographic chemicals in concentrated form and mixing them as needed. Acceptance testing ensures that the product meets expectations, ensures that its performance meets specifications, and establishes the operating level for the ongoing QC program.

  14. Quality control of biotechnology-derived vaccines: technical and regulatory considerations.

    PubMed

    Fuchs, Florence

    2002-11-01

    Vaccines for human use have been produced for decades using classical manufacturing methods including culture of viruses and bacteria followed by various concentration-, inactivation-, detoxification-, conjugation production processes. Availability of techniques for molecular biology and for the complete chemical synthesis of genes provides prospects of genetic engineering of microorganisms so as to generate novel biotechnological/biological-derived vaccines. The potential large-scale availability of biotechnology-derived vaccines makes feasible their evaluation in the prevention and/or treatment of various infectious, chronic, degenerative and cancer human diseases. There are potential safety concerns that arise from the novel manufacturing processes and from the complex structural and biological characteristics of the products. These products have distinguishing characteristics to which consideration should be given in a well-defined quality control testing programme. The evaluation of their quality, safety, efficacy and stability necessitate complex analytical methods and appropriate physicochemical, biochemical and immunochemical methods for the analysis of the molecular entity. A flexible approach to the control of these novel products is being developed by regulatory authorities so that recommendations can be modified in the light of experience of research and development in vaccinology, production and use of biotechnology products and with the further development of new technologies.

  15. Design and evaluation of vibratory shoe on balance control for elderly subjects: technical note.

    PubMed

    Aboutorabi, Atefeh; Arazpour, Mokhtar; Farahmand, Farzam; Bahramizadeh, Mahmood; Fadayevatan, Reza; Abdollahi, Ehsan

    2017-03-22

    Aging often results in a decline in somatosensory function, and such changes are associated with diminished motor performance. Input noise can enhance sensory and motor function through a mechanism known as stochastic resonance (SR). This paper describes the development and testing of a new vibrating shoe to possibly assist the elderly patients in controlling their balance and decreasing their falling risks. The new vibrating shoe was evaluated to ascertain its ability to generate appropriate random and nonlinear vibrations. The vibratory shoe performance in two young subjects with decreased foot sensation and two elderly subjects in different static and dynamic balance situations was also evaluated. The postural control, expressed by the stability index (SI), was significantly affected by SR in the older subjects. The vibrating motors could be recommended as a suitable solution for dynamic balance situations. Moreover, the new vibrating shoe could improve the age-related balance impairments in elderly subjects with balance deficiencies and others with impaired foot sensations. Implications for rehabilitations Older adults exhibited decreased postural stability. Noise signal improves sensation and proprioception in older people. New shoe with vibrating motors can operate in different dynamic situations.

  16. High-Efficiency Photovoltaic Devices using Trap-Controlled Quantum-Dot Ink prepared via Phase-Transfer Exchange.

    PubMed

    Aqoma, Havid; Al Mubarok, Muhibullah; Hadmojo, Wisnu Tantyo; Lee, Eun-Hye; Kim, Tae-Wook; Ahn, Tae Kyu; Oh, Seung-Hwan; Jang, Sung-Yeon

    2017-03-07

    Colloidal-quantum-dot (CQD) photovoltaic devices are promising candidates for low-cost power sources owing to their low-temperature solution processability and bandgap tunability. A power conversion efficiency (PCE) of >10% is achieved for these devices; however, there are several remaining obstacles to their commercialization, including their high energy loss due to surface trap states and the complexity of the multiple-step CQD-layer-deposition process. Herein, high-efficiency photovoltaic devices prepared with CQD-ink using a phase-transfer-exchange (PTE) method are reported. Using CQD-ink, the fabrication of active layers by single-step coating and the suppression of surface trap states are achieved simultaneously. The CQD-ink photovoltaic devices achieve much higher PCEs (10.15% with a certified PCE of 9.61%) than the control devices (7.85%) owing to improved charge drift and diffusion. Notably, the CQD-ink devices show much lower energy loss than other reported high-efficiency CQD devices. This result reveals that the PTE method is an effective strategy for controlling trap states in CQDs.

  17. The Rho-guanine nucleotide exchange factor Trio controls leukocyte transendothelial migration by promoting docking structure formation.

    PubMed

    van Rijssel, Jos; Kroon, Jeffrey; Hoogenboezem, Mark; van Alphen, Floris P J; de Jong, Renske J; Kostadinova, Elena; Geerts, Dirk; Hordijk, Peter L; van Buul, Jaap D

    2012-08-01

    Leukocyte transendothelial migration involves the active participation of the endothelium through the formation of apical membrane protrusions that embrace adherent leukocytes, termed docking structures. Using live-cell imaging, we find that prior to transmigration, endothelial docking structures form around 80% of all neutrophils. Previously we showed that endothelial RhoG and SGEF control leukocyte transmigration. In this study, our data reveal that both full-length Trio and the first DH-PH (TrioD1) domain of Trio, which can activate Rac1 and RhoG, interact with ICAM-1 and are recruited to leukocyte adhesion sites. Moreover, upon clustering of ICAM-1, the Rho-guanine nucleotide exchange factor Trio activates Rac1, prior to activating RhoG, in a filamin-dependent manner. We further show that docking structure formation is initiated by ICAM-1 clustering into ring-like structures, which is followed by apical membrane protrusion. Interestingly, we find that Rac1 is required for ICAM-1 clustering, whereas RhoG controls membrane protrusion formation. Finally, silencing endothelial Trio expression or reducing TrioD1 activity without affecting SGEF impairs both docking structure formation and leukocyte transmigration. We conclude that Trio promotes leukocyte transendothelial migration by inducing endothelial docking structure formation in a filamin-dependent manner through the activation of Rac1 and RhoG.

  18. Technical writing versus technical writing

    NASA Technical Reports Server (NTRS)

    Dillingham, J. W.

    1981-01-01

    Two terms, two job categories, 'technical writer' and 'technical author' are discussed in terms of industrial and business requirements and standards. A distinction between 'technical writing' and technical 'writing' is made. The term 'technical editor' is also considered. Problems inherent in the design of programs to prepare and train students for these jobs are discussed. A closer alliance between industry and academia is suggested as a means of preparing students with competent technical communication skills (especially writing and editing skills) and good technical skills.

  19. Electric Power Research Institute, Environmental Control Technology Center report to the Steering Committee. Final technical report

    SciTech Connect

    1995-07-01

    Operations and maintenance continued this month at the Electric Power Research Institute`s Environmental Control Technology Center. Testing on the 4.0 MW Pilot Wet FGD unit continued this month with the Trace Element Removal (TER) test block, and a simultaneous testing of the Lime Forced Oxidation process with DBA addition (LDG). At the end of the month, a series of Duct Injection tests began in a study to determine the efficiencies of alkaline injection for removing trace elements (mercury). On the Cold-Side Selective Catalytic Reduction (SCR) unit, low temperature performance testing continued this month as measurements were taken for NO{sub x} removal efficiency, residual ammonia slip, and SO{sub 3} generation across the catalysts installed in the SCR reactor. This report describes the status of the facilities and test activities at the pilot and mini-pilot plants.

  20. Electric Power Research Institute: Environmental control technology. Final technical monthly report

    SciTech Connect

    1995-06-01

    Operations and maintenance continued this month at the Electric Power Research Institute`s Environmental Control Technology Center. Testing on the 4.0 MW Pilot Wet FGD unit continued this month with the Trace Element Removal (TER) test block. A second phase of the lime Forced Oxidation process with DBA addition (LDG) was also conducted simultaneously on the Pilot System this month. This month the ECTC was off-line from 6/9 through 6/19 to complete a Facility retrofit project. During this brief outage, modifications were made to the ECTC Flue Gas Handling System to enhance the facility capabilities, and to prepare for future High Velocity Wet FGD Testing. On the Cold-Side Selective Catalytic Reduction (SCR) unit, the low temperature performance testing resumed this month as measurements were taken for NO{sub x} removal efficiency, residual ammonia slip, and SO{sub 3} generation across the new SCR catalysts.