Science.gov

Sample records for floating production system

  1. Topside facilities for floating production systems require new engineering thinking

    SciTech Connect

    Burn, A.J.; Graaf, G.

    1983-05-01

    Since the oil industry moved offshore, great emphasis has been placed on the need to reduce space and weight requirements of topside facilities. For successful design of floating production systems, weight consciousness assumes an even higher level of importance, necessitating systematic attention to detail even at the feasibility study stage of a project.

  2. Classification and certification requirements for floating production systems

    SciTech Connect

    Bowie, R.D.; Richardson, K.L.

    1995-12-31

    Floating Production Systems (FPSs) can be either, custom built or a converted semi-submersible, tanker or barge. The paper describes the necessary steps to be taken for the Classification and Certification of FPSs and FPSOS. The paper outlines the latest Classification and certification requirements for both semi-submersible and ship type FPSS. Classification and regulatory requirements for the Hull Structure, Stability, Station Keeping, Shipboard and Production Systems are discussed.

  3. Floating production systems for north Sea marginal fields

    SciTech Connect

    Snowden, D.P.

    1984-05-01

    The economic exploitation of marginal offshore fields through production systems based on the use of articulated columns has been the subject of an intensive two year development project executed by Taywood Engineering Ltd. A range of systems for Continental Shelf water depths have been evaluated in detail, and their possible extension into deeper waters has been investigated. This paper outlines the detailed engineering development to conceptual design level of two floating production systems, one employing a heavy duty semi-submersible, the other employing a converted tanker, both permanently linked to articulated columns. Descriptions are given of the extensive development of computer software to enable the accurate predicition of environmental loadings and system motion responses, and of the validation of this software using in-house wave tank model testing facilities. In the development of both designs, emphasis has been placed on enhancing the recovery and profitability of the field by offering improved reservoir control and cost-effective fabrication techniques, without introducing innovative technology. First-order cost estimate and economic analyses of the two systems are presented for particular reference fields to enable their comparison against current systems.

  4. Floating production system for deep waters, marginal fields

    SciTech Connect

    Not Available

    1984-06-01

    Concrete platform expertise developed by Norwegian Contractors has been applied to a floating production concept thought to offer considerable potential for marginal and deep-water oil fields. The design is based on a multicell Monotower solution and represents the outcome of studies reaching back to 1978. This work has focused chiefly on devising a production system for Gulf's gas/condensate discovery in 380 m water on Norwegian North Sea Block 35/8. Components covered by the conceptual design study include the catenary anchored concrete floater with condensate storage, subsea and riser systems for high-pressure gas production and topside facilities for gas and condensate treatment. A system also has been developed for periodic direct loading of condensate into a shuttle tanker, which is allowed to weathervane through 360/sup 0/ around the platform. Claimed to offer better motion characteristics than a conventional semisubmersible, the weight-stable platform comprises a series of cylindrical columns arranged in a circle, an inner ring of moonpool cells and a cantilevered base for storage.

  5. 33 CFR 147.847 - Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety Zone; BW PIONEER Floating... ZONES § 147.847 Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone. (a) Description. The BW PIONEER, a Floating Production, Storage and Offloading (FPSO) system, is...

  6. 33 CFR 147.847 - Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; BW PIONEER Floating... ZONES § 147.847 Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone. (a) Description. The BW PIONEER, a Floating Production, Storage and Offloading (FPSO) system, is...

  7. Concrete production floating platforms

    SciTech Connect

    Letourneur, O.; Falcimaigne, J.

    1981-01-01

    The floating production platforms operating in the North Sea are adapted from drilling semisubmersibles which allow only a limited payload capacity. Experience of concrete production platforms constructed for the North Sea has led Sea Tank Co. to propose a floating platform which offers large payload and oil storage capacities similar to those of existing fixed platforms. Sea Tank Co. and Institut Francais du Petrole joined forces in early 1976 to study the feasibility of a concrete floating production platform incorporating the structure and the production riser together. The results of this 3-yr program show that the concrete floating structure is economically attractive for permanent utilization on a production site. Furthermore, concrete has definite advantages over other materials, in its long term behavior.

  8. Floating nut retention system

    NASA Technical Reports Server (NTRS)

    Charles, J. F.; Theakston, H. A. (Inventor)

    1980-01-01

    A floating nut retention system includes a nut with a central aperture. An inner retainer plate has an opening which is fixedly aligned with the nut aperture. An outer retainer member is formed of a base plate having an opening and a surface adjacent to a surface of the inner retainer plate. The outer retainer member includes a securing mechanism for retaining the inner retainer plate adjacent to the outer retainer member. The securing mechanism enables the inner retainer plate to float with respect to the outer retainer number, while simultaneously forming a bearing surface for inner retainer plate.

  9. Floating platform well production apparatus

    SciTech Connect

    Nobileau, P.C.

    1980-10-21

    A plurality of wells are clustered around a central riser which is maintained under tension from a floating platform. A plurality of spiders on the riser carry funnels in vertical alignment with the wells. The funnels are sufficiently large to permit the passage of wellhead connectors and master block valves, and the production risers include centralizers which brace the production riser from the funnels through a limited vertical range. Tensioning of the production riser is with a lower force and through a limited range which precludes disengagement of the centralizers from the funnel. Some centralizers are located to facilitate entry and attachment to the wellhead.

  10. Floating wind turbine system

    NASA Technical Reports Server (NTRS)

    Viterna, Larry A. (Inventor)

    2009-01-01

    A floating wind turbine system with a tower structure that includes at least one stability arm extending therefrom and that is anchored to the sea floor with a rotatable position retention device that facilitates deep water installations. Variable buoyancy for the wind turbine system is provided by buoyancy chambers that are integral to the tower itself as well as the stability arm. Pumps are included for adjusting the buoyancy as an aid in system transport, installation, repair and removal. The wind turbine rotor is located downwind of the tower structure to allow the wind turbine to follow the wind direction without an active yaw drive system. The support tower and stability arm structure is designed to balance tension in the tether with buoyancy, gravity and wind forces in such a way that the top of the support tower leans downwind, providing a large clearance between the support tower and the rotor blade tips. This large clearance facilitates the use of articulated rotor hubs to reduced damaging structural dynamic loads. Major components of the turbine can be assembled at the shore and transported to an offshore installation site.

  11. Drilling and production from a floating spar

    SciTech Connect

    Brooks, I.H.; Carroll, J.P.

    1994-12-31

    A deepwater drilling and production platform has been designed based on a floating spar. The spar is a catenary-moored cylindrical vessel having a deep draft which minimizes heave motions. The concept is an economic competitor with other deep water designs such as compliant towers and tension leg platforms. The spar`s oil storage capacity makes it particularly applicable for remote areas where pipeline infrastructure is unavailable and production is primarily from oil reservoirs. Without the need for a swivel, offloading of oil can be accomplished either directly from the spar, by use of a floating hose and support vessel, or by transfer to an offloading buoy. The concept is compatible with early production or phased development scenarios, permits surface completions of producing and injection wells, and allows for direct well intervention. The ability to reposition the spar by manipulations of the mooring lines favors a system of individual wellheads on the seafloor. Wells can be drilled, completed, and produced without pulling the drilling riser. When production from the field reaches its economic limit, the entire system can be towed to a new location and reused.

  12. A co-beneficial system using aquatic plants: bioethanol production from free-floating aquatic plants used for water purification.

    PubMed

    Soda, S; Mishima, D; Inoue, D; Ike, M

    2013-01-01

    A co-beneficial system using constructed wetlands (CWs) planted with aquatic plants is proposed for bioethanol production and nutrient removal from wastewater. The potential for bioethanol production from aquatic plant biomass was experimentally evaluated. Water hyacinth and water lettuce were selected because of their high growth rates and easy harvestability attributable to their free-floating vegetation form. The alkaline/oxidative pretreatment was selected for improving enzymatic hydrolysis of the aquatic plants. Ethanol was produced with yields of 0.14-0.17 g-ethanol/ g-biomass in a simultaneous saccharification and fermentation mode using a recombinant Escherichia coli strain or a typical yeast strain Saccharomyces cerevisiae. Subsequently, the combined benefits of the CWs planted with the aquatic plants for bioethanol production and nutrient removal were theoretically estimated. For treating domestic wastewater at 1,100 m(3)/d, it was inferred that the anoxic-oxic activated sludge process consumes energy at 3,200 MJ/d, whereas the conventional activated sludge process followed by the CW consumes only 1,800 MJ/d with ethanol production at 115 MJ/d. PMID:23752400

  13. Floating production unit to work off Brazil

    SciTech Connect

    Not Available

    1992-10-19

    This paper reports that Petroleo Brasileiro SA expects by early November to deploy its Petrobras XXIV floating production unit (FPU) in about 900 ft of water in Albacora field off Brazil. The FPU was scheduled to depart Galveston, Tex., this month, following completion of modifications and upgrades under a turnkey contract with Chiles Offshore International Inc. Chiles began modifying Petrobras XXIV about 1 year ago as part of a deal closed in October 1991 in which Chiles Offshore Corp. sold the vessel, then known as Intrepid, to Brasoil, the international subsidiary of Petrobras.

  14. Proton production, neutralisation and reduction in a floating water bridge

    NASA Astrophysics Data System (ADS)

    Sammer, Martina; Wexler, Adam D.; Kuntke, Philipp; Wiltsche, Helmar; Stanulewicz, Natalia; Lankmayr, Ernst; Woisetschläger, Jakob; Fuchs, Elmar C.

    2015-10-01

    This work reports on proton production, transport, reduction and neutralization in floating aqueous bridges under the application of a high dc voltage (‘floating water bridge’). Recently possible mechanisms for proton transfer through the bridge were suggested. In this work we visualize and describe the production of protons in the anolyte and their neutralization in the catholyte. Apart from that, protons are reduced to hydrogen due to electrolysis. Microbubbles are detached instantly, due to the electrohydrodynamic flow at the electrode surface. No larger, visible bubbles are formed and the system degasses through the bridge due to its higher local temperature. A detailed analysis of trace elements originating from beaker material, anode or the atmosphere is presented, showing that their influence on the overall conduction compared to the contribution of protons is negligible. Finally, an electrochemical rationale of high voltage electrolysis of low ionic strength solutions is presented.

  15. Floating seal system for rotary devices

    DOEpatents

    Banasiuk, H.A.

    1983-08-23

    This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10[degree] to about 30[degree] in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device. 5 figs.

  16. Floating seal system for rotary devices

    DOEpatents

    Banasiuk, Hubert A.

    1983-01-01

    This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10.degree. to about 30.degree. in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device.

  17. Sonar location system for freely floating buoys

    NASA Astrophysics Data System (ADS)

    Bird, I. G.

    1983-05-01

    A rf interrogated sonar location system for freely floating buoys is described. The location of an array of up to three buoys may be determined on an almost continuous basis within a radius of 500 m from a shipboard monitoring station. Location accuracy of typically ±0.5 m at 200-m range, low cost, and ease of operation are the major features of the system.

  18. Subtropical Productivity from Profiling Floats and Gliders

    NASA Astrophysics Data System (ADS)

    Nicholson, D. P.; Johnson, K. S.; Karl, D. M.

    2015-12-01

    Since 2007 profiling floats equipped with dissolved oxygen and nitrate sensors have been released from the Hawaii Ocean Time-series (HOT) and Bermuda Atlantic Time-series Study (BATS) sites and can be calibrated using time-series observations. More recent deployments have also included bio-optical and pH sensors. Gliders with oxygen sensors and bio-optics have been intermittently deployed near HOT Station ALOHA since 2008 and at BATS since 2014. While gliders maintain a restricted survey region near the time-series stations, profiling floats drifted widely across the subtropical gyres. Multiple floats and gliders enables a cotemporaneous comparison of biogeochemical processes across gyres. These platforms enable observations on spatial scales from submesoscale to basin scale and on temporal scales from diel to interannual. Here, I focus on the spatiotemporal variability of nitrate and oxygen mass balances in the North Pacific and North Atlantic subtropical gyres using a data-assimilating and float-tracking 1D upper ocean model.

  19. Floating oil production unit slated in small field off Gabon

    SciTech Connect

    Not Available

    1991-10-14

    This paper reports on the first U.S. tanker converted to a floating production, storage, and offloading (FPSO) unit which takes up station in Gombe-Beta field off Gabon by Dec. 1. FPSO Ocean Producer will work under a 3 year, day rate contract let late in 1990 by Amoco-Gabon Bombe Marin co., a unit of Amoco Production Co. (OGJ, Dec. 24, 1990, p. 27). Gombe-Beta field is in the Atlantic Ocean about 70 miles south of Port Gentil, Gabon. Ocean Producer will be moored in 50 ft of water 3.7 miles off Gabon, with Bombe-Beta's unmanned production platform about 820 ft astern. The vessel will be held in position by a disconnectable, asymmetric, six point, spread mooring system, It is owned and operated by Oceaneering International Services Ltd. (OISL). Affiliate Oceaneering Production Systems (OPS) converted the 78,061 dwt oil tanker MT Baltimore Sea at a capital cost of $25 million at Gulf Copper Manufacturing Corp.'s Port Arthur, Tex., shipyard. Both companies are units of Oceaneering International Inc., Houston. OPS the Ocean Producer's use in Gombe-Beta field is the shallowest water FPSO application in the world. Amoco-Gabon chose an FPSO production system for Gombe-Beta because it expects the remote field to have a short economic life, and the oil requires extensive processing.

  20. Feasibility of Floating Platform Systems for Wind Turbines: Preprint

    SciTech Connect

    Musial, W.; Butterfield, S.; Boone, A.

    2003-11-01

    This paper provides a general technical description of several types of floating platforms for wind turbines. Platform topologies are classified into multiple- or single-turbine floaters and by mooring method. Platforms using catenary mooring systems are contrasted to vertical mooring systems and the advantages and disadvantages are discussed. Specific anchor types are described in detail. A rough cost comparison is performed for two different platform architectures using a generic 5-MW wind turbine. One platform is a Dutch study of a tri-floater platform using a catenary mooring system, and the other is a mono-column tension-leg platform developed at the National Renewable Energy Laboratory. Cost estimates showed that single unit production cost is $7.1 M for the Dutch tri-floater, and $6.5 M for the NREL TLP concept. However, value engineering, multiple unit series production, and platform/turbine system optimization can lower the unit platform costs to $4.26 M and $2.88 M, respectively, with significant potential to reduce cost further with system optimization. These foundation costs are within the range necessary to bring the cost of energy down to the DOE target range of $0.05/kWh for large-scale deployment of offshore floating wind turbines.

  1. The effect of floating vegetation on denitrification and greenhouse gas production in wetland mesocosms

    NASA Astrophysics Data System (ADS)

    Jacobs, A. E.; Harrison, J. A.

    2012-12-01

    Anthropogenic intensification of nitrogen (N) loading to aquatic ecosystems is widespread and can lead to the degradation of these systems. Wetlands are important sites for N removal via denitrification, the microbially mediated reduction of reactive nitrate to inert N2 gas, but they can also produce high levels of greenhouse gases. Floating plants play an important role in encouraging denitrification, since they create low oxygen conditions that may favor denitrification. We investigated whether wetland sediments with floating plant cover had higher denitrification and greenhouse gas production rates than wetland sediments without floating plants. Replicate flow-through mesocosms with wetland sediment and water were constructed in a growth chamber to mimic the wetland where the sediment and water were collected. Mesocosm treatments were covered with floating vegetation (duckweed), an opaque tarp, or no cover to determine how cover type affects denitrification and greenhouse gas production and whether biotic or abiotic factors are likely responsible for observed differences. Denitrification and greenhouse gas production rates were calculated by measuring excess N2 gas, methane, and nitrous oxide concentrations in the water column and measuring the gas exchange rates between the water column and the atmosphere. Gas exchange rates were measured using an inert volatile tracer added to the water column and accumulation of gas in the mesocosm headspace. Additional mesocosm experiments were performed to determine how duckweed-dominated wetland systems respond to nitrogen loading and which mechanism for lowering dissolved oxygen concentrations is important in affecting denitrification under floating vegetation. Mesocosms with floating vegetation had lower dissolved oxygen than no cover or tarp-covered mesocosms, which is consistent with field and literature observations. Water flowing out of the mesocosms had statistically lower total nitrogen and nitrate concentrations

  2. Classifying Floating Potential Measurement Unit Data Products as Science Data

    NASA Technical Reports Server (NTRS)

    Coffey, Victoria; Minow, Joseph

    2015-01-01

    We are Co-Investigators for the Floating Potential Measurement Unit (FPMU) on the International Space Station (ISS) and members of the FPMU operations and data analysis team. We are providing this memo for the purpose of classifying raw and processed FPMU data products and ancillary data as NASA science data with unrestricted, public availability in order to best support science uses of the data.

  3. Porous carrier based floating granular delivery system of repaglinide.

    PubMed

    Jain, Sunil K; Agrawal, Govind P; Jain, Narendra K

    2007-04-01

    A floating granular delivery system consisting of calcium silicate (CS) as porous carrier; repaglinide (Rg), an oral hypoglycemic agent; and hydroxypropyl methylcellulose K4M (HPMC K4M), ethyl cellulose (EC) and carbopol 940 (CP940) as matrix forming polymers was prepared and evaluated for its gastro-retentive and controlled release properties. The effect of various formulation and process variables on the particle morphology, micromeritic properties, in vitro floating behavior, drug content (%) and in vitro drug release was studied. The transit of floating granules of optimized formulation in the gastrointestinal (GI) tract was monitored by gamma scintigraphy in albino rabbits. The optimized formulation was compared in vivo with lactose granules (RgSCLG) prepared from identical polymers with their optimized composition ratio. Repaglinide-loaded optimized formulation was orally administered to albino rabbits and blood samples collected were used to determine pharmacokinetic parameters of Rg from floating granular formulation. Results were compared with pharmacokinetic parameters of marketed tablet formulation of Rg. The optimized formulation (RgSCG4) demonstrated favorable in vitro floating and release characteristics. Prolonged gastric residence time (GRT) of over 6 hr was achieved in all subjects for calcium silicate based floating granules of Rg. The relative bioavailability of Rg-loaded floating granules increased 3.8-fold in comparison to that of its marketed capsule. The designed system, combining excellent buoyant ability and suitable drug release pattern, offered clear advantages in terms of increased bioavailability of repaglinide. PMID:17523003

  4. Wireless telemetry system for floating bodies

    NASA Technical Reports Server (NTRS)

    Fain, L. T.; Cribb, H. E.

    1974-01-01

    Unit includes rugged waterproof cables and equipment containers, low power, sturdy antenna construction, and easy equipment setup and serviceability. Accuracy and reliability of entire measurement system were not sacrificed.

  5. Designs and applications for floating-hydro power systems in small streams

    SciTech Connect

    Rehder, J.B.

    1983-01-01

    The project focuses on an appropriate technology for small-scale hydro power: floating waterwheels and turbines. For background, relic and existing systems such as early floating mills, traditional Amish waterwheels, and micro-hydro systems are examined. In the design phase of the project, new designs for Floating Hydro Power Systems include: an analysis of floatation materials and systems; a floating undershot waterwheel design; a floating cylinder (fiberglass storage tank) design; a submerged tube design; and a design for a floating platform with submerged propellers. Finally, in the applications phase, stream flow data from East Tennessee streams are used in a discussion of the potential applications of floating hydro power systems in small streams.

  6. Design and optimization of floating drug delivery system of acyclovir.

    PubMed

    Kharia, A A; Hiremath, S N; Singhai, A K; Omray, L K; Jain, S K

    2010-09-01

    The purpose of the present work was to design and optimize floating drug delivery systems of acyclovir using psyllium husk and hydroxypropylmethylcellulose K4M as the polymers and sodium bicarbonate as a gas generating agent. The tablets were prepared by wet granulation method. A 3(2) full factorial design was used for optimization of drug release profile. The amount of psyllium husk (X1) and hydroxypropylmethylcellulose K4M (X2) were selected as independent variables. The times required for 50% (t(50%)) and 70% (t(70%)) drug dissolution were selected as dependent variables. All the designed nine batches of formulations were evaluated for hardness, friability, weight variation, drug content uniformity, swelling index, in vitro buoyancy, and in vitro drug release profile. All formulations had floating lag time below 3 min and constantly floated on dissolution medium for more than 24 h. Validity of the developed polynomial equation was verified by designing two check point formulations (C1 and C2). The closeness of predicted and observed values for t(50%) and t(70%) indicates validity of derived equations for the dependent variables. These studies indicated that the proper balance between psyllium husk and hydroxypropylmethylcellulose K4M can produce a drug dissolution profile similar to the predicted dissolution profile. The optimized formulations followed Higuchi's kinetics while the drug release mechanism was found to be anomalous type, controlled by diffusion through the swollen matrix. PMID:21694992

  7. Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint

    SciTech Connect

    Wayman, E. N.; Sclavounos, P. D.; Butterfield, S.; Jonkman, J.; Musial, W.

    2006-03-01

    This article presents a collaborative research program that the Massachusetts Institute of Technology (MIT) and the National Renewable Energy Laboratory (NREL) have undertaken to develop innovative and cost-effective floating and mooring systems for offshore wind turbines in water depths of 10-200 m. Methods for the coupled structural, hydrodynamic, and aerodynamic analysis of floating wind turbine systems are presented in the frequency domain. This analysis was conducted by coupling the aerodynamics and structural dynamics code FAST [4] developed at NREL with the wave load and response simulation code WAMIT (Wave Analysis at MIT) [15] developed at MIT. Analysis tools were developed to consider coupled interactions between the wind turbine and the floating system. These include the gyroscopic loads of the wind turbine rotor on the tower and floater, the aerodynamic damping introduced by the wind turbine rotor, the hydrodynamic damping introduced by wave-body interactions, and the hydrodynamic forces caused by wave excitation. Analyses were conducted for two floater concepts coupled with the NREL 5-MW Offshore Baseline wind turbine in water depths of 10-200 m: the MIT/NREL Shallow Drafted Barge (SDB) and the MIT/NREL Tension Leg Platform (TLP). These concepts were chosen to represent two different methods of achieving stability to identify differences in performance and cost of the different stability methods. The static and dynamic analyses of these structures evaluate the systems' responses to wave excitation at a range of frequencies, the systems' natural frequencies, and the standard deviations of the systems' motions in each degree of freedom in various wind and wave environments. This article in various wind and wave environments. This article explores the effects of coupling the wind turbine with the floating platform, the effects of water depth, and the effects of wind speed on the systems' performance. An economic feasibility analysis of the two concepts

  8. Preformulation studies and optimization of sodium alginate based floating drug delivery system for eradication of Helicobacter pylori.

    PubMed

    Diós, Péter; Nagy, Sándor; Pál, Szilárd; Pernecker, Tivadar; Kocsis, Béla; Budán, Ferenc; Horváth, Ildikó; Szigeti, Krisztián; Bölcskei, Kata; Máthé, Domokos; Dévay, Attila

    2015-10-01

    The aim of this study was to design a local, floating, mucoadhesive drug delivery system containing metronidazole for Helicobacter pylori eradication. Face-centered central composite design (with three factors, in three levels) was used for evaluation and optimization of in vitro floating and dissolution studies. Sodium alginate (X1), low substituted hydroxypropyl cellulose (L-HPC B1, X2) and sodium bicarbonate (X3) concentrations were the independent variables in the development of effervescent floating tablets. All tablets showed acceptable physicochemical properties. Statistical analysis revealed that tablets with 5.00% sodium alginate, 38.63% L-HPC B1 and 8.45% sodium bicarbonate content showed promising in vitro floating and dissolution properties for further examinations. Optimized floating tablets expressed remarkable floating force. Their in vitro dissolution studies were compared with two commercially available non-floating metronidazole products and then microbiologically detected dissolution, ex vivo detachment force, rheological mucoadhesion studies and compatibility studies were carried out. Remarkable similarity (f1, f2) between in vitro spectrophotometrically and microbiologically detected dissolutions was found. Studies revealed significant ex vivo mucoadhesion of optimized tablets, which was considerably increased by L-HPC. In vivo X-ray CT studies of optimized tablets showed 8h gastroretention in rats represented by an animation prepared by special CT technique. PMID:26247118

  9. Nitrate removal from polluted water by using a vegetated floating system.

    PubMed

    Bartucca, Maria Luce; Mimmo, Tanja; Cesco, Stefano; Del Buono, Daniele

    2016-01-15

    Nitrate (NO3(-)) water pollution is one of the most prevailing and relevant ecological issues. For instance, the wide presence of this pollutant in the environment is dramatically altering the quality of superficial and underground waters. Therefore, we set up a floating bed vegetated with a terrestrial herbaceous species (Italian ryegrass) with the aim to remediate hydroponic solutions polluted with NO3(-). The floating bed allowed the plants to grow and achieve an adequate development. Ryegrass was not affected by the treatments. On the contrary, plant biomass production and total nitrogen content (N-K) increased proportionally to the amount of NO3(-) applied. Regarding to the water cleaning experiments, the vegetated floating beds permitted to remove almost completely all the NO3(-) added from the hydroponic solutions with an initial concentration of 50, 100 and 150 mg L(-1). Furthermore, the calculation of the bioconcentration factor (BCF) indicated this species as successfully applicable for the remediation of solutions polluted by NO3(-). In conclusion, the results highlight that the combination of ryegrass and the floating bed system resulted to be effective in the remediation of aqueous solutions polluted by NO3(-). PMID:26562338

  10. System for deflection measurements of floating dry docks

    NASA Astrophysics Data System (ADS)

    Gorbachev, Alexey A.; Pantyushin, Anton V.; Serikova, Mariya G.; Korotaev, Valery V.; Timofeev, Aleksandr N.

    2015-05-01

    In this paper we introduce a system for deflection measurement of floating dry docks. The system contains two measurement channels observing opposite directions of the dock. It also includes set of reference marks, an industrial computer and a display. Each channel contains CMOS camera with long focal-length lens. Reference marks are implemented as IR LED arrays with 940 nm working wavelength for better performance within bad weather conditions (e.g. fog, rain, high humidity etc.). In the paper we demonstrate results of an analysis of different optical schemes for coupling the oppositely directed channels of the measurement unit and show that the scheme with two image sensors with separated lenses is an optimal option, because it allows usage of nonequidistant location of reference marks and demonstrates the least value of parasitic shift caused by rotations of the measuring unit. The developed system was tested both on specially-designed setup and in real infrastructure of a floating dry dock. The conducted tests proved that a measuring error of the system is smaller than +/- 1.5 mm within the measurement range of +/- 150 mm when deflection of 100 m dock is measured. Obtained results showed that the system demonstrates an ability to work in a harsh environment including poor weather conditions.

  11. Flexible dynamic riser for floating-production facility in the North Sea

    SciTech Connect

    Pettenati, C.; Dumay, J.M.

    1983-09-01

    When considering the production riser aspect of a floating-production facility project, two systems can be generally envisaged: - The rigid steel, tensioned multiple riser. - The flexible, dynamic riser. Although this last one was successfully introduced in Brazil as early as 1978, and since then has proved to be an extremely reliable solution in several other parts of the world as well, for other major operators, the industry in general was still recently expressing some concern about its introduction in an extreme-weather environment such as the North Sea. A more classic and well-known technique such as the steel tensioned riser was generally favoured by companies operating in this hostile context. (Ex: Argyll, Buchan). This paper describing what can be considered as a typical development involving flexible, dynamic risers in the North Sea, presents evidence that this concern, although understandable, is mostly unfounded and that on the contrary, the flexible, dynamic riser represents a very considerable improvement in the reliability and efficiency of a floating-facility offshore development.

  12. Bread board float zone experiment system for high purity silicon

    NASA Technical Reports Server (NTRS)

    Kern, E. L.; Gill, G. L., Jr.

    1982-01-01

    A breadboard float zone experimental system has been established at Westech Systems for use by NASA in the float zone experimental area. A used zoner of suitable size and flexibility was acquired and installed with the necessary utilities. Repairs, alignments and modifications were made to provide for dislocation free zoning of silicon. The zoner is capable of studying process parameters used in growing silicon in gravity and is flexible to allow trying of new features that will test concepts of zoning in microgravity. Characterizing the state of the art molten zones of a growing silicon crystal will establish the data base against which improvements of zoning in gravity or growing in microgravity can be compared. 25 mm diameter was chosen as the reference size, since growth in microgravity will be at that diameter or smaller for about the next 6 years. Dislocation free crystals were growtn in the 100 and 111 orientations, using a wide set of growth conditions. The zone shape at one set of conditions was measured, by simultaneously aluminum doping and freezing the zone, lengthwise slabbing and delineating by etching. The whole set of crystals, grown under various conditions, were slabbed, polished and striation etched, revealing the growth interface shape and the periodic and aperiodic natures of the striations.

  13. Floating production platforms and their applications in the development of oil and gas fields in the South China Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Dagang; Chen, Yongjun; Zhang, Tianyu

    2014-03-01

    This paper studies the current available options for floating production platforms in developing deepwater oil fields and the potential development models of future oil and gas exploration in the South China Sea. A detailed review of current deepwater platforms worldwide was performed through the examples of industry projects, and the pros and cons of each platform are discussed. Four types of platforms are currently used for the deepwater development: tension leg platform, Spar, semi-submersible platform, and the floating production system offloading. Among these, the TLP and Spar can be used for dry tree applications, and have gained popularity in recent years. The dry tree application enables the extension of the drilling application for fixed platforms into floating systems, and greatly reduces the cost and complexity of the subsea operation. Newly built wet tree semi-submersible production platforms for ultra deepwater are also getting their application, mainly due to the much needed payload for deepwater making the conversion of the old drilling semi-submersible platforms impossible. These platforms have been used in different fields around the world for different environments; each has its own advantages and disadvantages. There are many challenges with the successful use of these floating platforms. A lot of lessons have been learned and extensive experience accumulated through the many project applications. Key technologies are being reviewed for the successful use of floating platforms for field development, and potential future development needs are being discussed. Some of the technologies and experience of platform applications can be well used for the development of the South China Sea oil and gas field.

  14. System and method for floating-substrate passive voltage contrast

    DOEpatents

    Jenkins, Mark W.; Cole, Jr., Edward I.; Tangyunyong, Paiboon; Soden, Jerry M.; Walraven, Jeremy A.; Pimentel, Alejandro A.

    2009-04-28

    A passive voltage contrast (PVC) system and method are disclosed for analyzing ICs to locate defects and failure mechanisms. During analysis a device side of a semiconductor die containing the IC is maintained in an electrically-floating condition without any ground electrical connection while a charged particle beam is scanned over the device side. Secondary particle emission from the device side of the IC is detected to form an image of device features, including electrical vias connected to transistor gates or to other structures in the IC. A difference in image contrast allows the defects or failure mechanisms be pinpointed. Varying the scan rate can, in some instances, produce an image reversal to facilitate precisely locating the defects or failure mechanisms in the IC. The system and method are useful for failure analysis of ICs formed on substrates (e.g. bulk semiconductor substrates and SOI substrates) and other types of structures.

  15. Definition of the Semisubmersible Floating System for Phase II of OC4

    SciTech Connect

    Robertson, A.; Jonkman, J.; Masciola, M.; Song, H.; Goupee, A.; Coulling, A.; Luan, C.

    2014-09-01

    Phase II of the Offshore Code Comparison Collaboration Continuation (OC4) project involved modeling of a semisubmersible floating offshore wind system as shown below. This report documents the specifications of the floating system, which were needed by the OC4 participants for building aero-hydro-servo-elastic models.

  16. Definition of the Floating System for Phase IV of OC3

    SciTech Connect

    Jonkman, J.

    2010-05-01

    Phase IV of the IEA Annex XXIII Offshore Code Comparison Collaboration (OC3) involves the modeling of an offshore floating wind turbine. This report documents the specifications of the floating system, which are needed by the OC3 participants for building aero-hydro-servo-elastic models.

  17. Floating data acquisition system for microwave calorimeter measurements on MTX

    SciTech Connect

    Sewall, N.R.; Meassick, S. )

    1989-09-13

    A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles are located inside the tokamak about 1 cm outside of the limiter radius at machine potential. The success of this measurement depends on our ability to float the data acquisition system near machine potential and isolate it from the rest of the vault ground system. Our data acquisition system has 48 channels of thermistor signal conditioning, a multiplexer and digitizer section, a serial data formatter, and a fiber-optic transmitter to send the data out. Additionally, we bring timing signals to the interface through optical fibers to tell it when to begin measurement, while maintaining isolation. The receiver is an HP 200 series computer with a serial data interface; the computer provides storage and local display for the shot temperature profile. Additionally, the computer provides temporary storage of the data until it can be passed to a shared resource management system for archiving. 2 refs., 6 figs.

  18. Novel Strategy to Fabricate Floating Drug Delivery System Based on Sublimation Technique.

    PubMed

    Huanbutta, Kampanart; Limmatvapirat, Sontaya; Sungthongjeen, Srisagul; Sriamornsak, Pornsak

    2016-06-01

    The present study aims to develop floating drug delivery system by sublimation of ammonium carbonate (AMC). The core tablets contain a model drug, hydrochlorothiazide, and various levels (i.e., 0-50% w/w) of AMC. The tablets were then coated with different amounts of the polyacrylate polymers (i.e., Eudragit® RL100, Eudragit® RS100, and the mixture of Eudragit® RL100 and Eudragit® RS100 at 1:1 ratio). The coated tablets were kept at ambient temperature (25°C) or cured at 70°C for 12 h before further investigation. The floating and drug release behaviors of the tablets were performed in simulated gastric fluid USP without pepsin at 37°C. The results showed that high amount of AMC induced the floating of the tablets. The coated tablets containing 40 and 50% AMC floated longer than 8 h with a time-to-float of about 3 min. The sublimation of AMC from the core tablets decreased the density of system, causing floating of the tablets. The tablets coated with Eudragit® RL100 floated at a faster rate than those of Eudragit® RS100. Even the coating level of polymer did not influence the time-to-float and floating time of coated tablets containing the same amount of AMC, the drug release from the tablets coated with higher coating level of polymer showed slower drug release. The results suggested that the sublimation technique using AMC is promising for the development of floating drug delivery system. PMID:26314245

  19. Role of excipients and polymeric advancements in preparation of floating drug delivery systems

    PubMed Central

    Kaushik, Avinash Y; Tiwari, Ajay K; Gaur, Ajay

    2015-01-01

    Since decade or two, the development of floating drug delivery systems becomes a significant and novel tool as having low density than gastric content. There are various advanced polymers including chitosan, eudragit, etc., and excipients such as; pore forming agent, surfactants, etc. All of them are discussed briefly, and results are concluded from various reputed researches. We have discussed all natural and synthetic systems with their effect on the release and other parameters which are essential for the floating formulation development. PMID:25599027

  20. Formulation and evaluation of floating oral in situ gelling system of amoxicillin.

    PubMed

    Patel, Dasharath M; Patel, Divyesh K; Patel, Chhagan N

    2011-01-01

    Purpose. Effective Helicobacter pylori eradication requires delivery of the antibiotic locally in the stomach. High dose of amoxicillin (750 to 1000 mg) is difficult to incorporate in floating tablets but can easily be given in liquid dosage form. Keeping the above facts in mind, we made an attempt to develop a new floating in situ gelling system of amoxicillin with increased residence time using sodium alginate as gelling polymer to eradicate H. pylori. Methods. Floating in situ gelling formulations were prepared using sodium alginate, calcium chloride, sodium citrate, hydroxypropyl methyl cellulose K100, and sodium bicarbonate. The prepared formulations were evaluated for solution viscosity, floating lag time, total floating time, and in vitro drug release. The formulation was optimized using a 3(2) full factorial design. Dissolution data were fitted to various models to ascertain kinetic of drug release. Regression analysis and analysis of variance were performed for dependent variables. Results. All formulations (F(1)-F(9)) showed floating within 30 s and had total floating time of more than 24 h. All the formulations showed good pourability. It was observed that concentration of sodium alginate and HPMC K100 had significant influence on floating lag time, cumulative percentage drug release in 6 h and 10 h. The batch F(8) was considered optimum since it showed more similarity in drug release (f(2) = 74.38) to the theoretical release profile. Conclusion. Floating in situ gelling system of amoxicillin can be formulated using sodium alginate as a gelling polymer to sustain the drug release for 10 to 12 h with zero-order release kinetics. PMID:22389849

  1. Design and in vitro evaluation of multiparticulate floating drug delivery system of zolpidem tartarate.

    PubMed

    Amrutkar, P P; Chaudhari, P D; Patil, S B

    2012-01-01

    Zolpidem tartarate is a non-benzodiazepine, sedative-hypnotic, which finds its major use in various types of insomnia. The present work relates to development of multiparticulate floating drug delivery system based on gas generation technique to prolong the gastric residence time and to increase the overall bioavailability. Modified release dosage form of zolpidem tartarate adapted to release over a predetermined time period, according to biphasic profile of dissolution, where the first phase is immediate release phase for inducing the sleep and the second phase is modified release phase for maintaining the sleep up to 10 h. The system consists of zolpidem tartarate layered pellets coated with effervescent layer and polymeric membrane. The floating ability and in vitro drug release of the system were dependent on amount of the effervescent agent (sodium bicarbonate) layered onto the drug layered pellets, and coating level of the polymeric membrane (Eudragit(®) NE 30D). The system could float completely within 5 min and maintain the floating over a period of 10 h. The multiparticulate floating delivery system of zolpidem tartarate with rapid floating and modified drug release was obtained. PMID:21974910

  2. In vitro evaluation of porous carrier-based floating granular delivery system of orlistat.

    PubMed

    Jain, Sunil K; Agrawal, G P; Jain, N K

    2008-01-01

    The purpose of the study is to prepare and evaluate an intragastric floating granular delivery system of orlistat using (i) calcium silicate as porous carrier; and (ii) hydroxypropyl methylcellulose K4M, ethyl cellulose, and Carbopol 940 as matrix-forming polymers. The effect of various formulation and process variables on the micro-meritic properties, in vitro floating behavior, percent drug content, and in vitro drug release was studied. The release mechanism of orlistat from these granules was evaluated on the basis of various theoretical equations. The optimized formulation demonstrated favorable in vitro floating and release characteristics. The release pattern of optimized, secondary-coated granules of orlistat in simulated gastrointestinal fluids corresponded best to the Peppas-Korsmeyer model and Higuchi matrix model. The results clearly indicated the controlled and sustained release of orlistat from its gastro-retentive floating granular delivery system. PMID:19174957

  3. A modified emulsion gelation technique to improve buoyancy of hydrogel tablets for floating drug delivery systems.

    PubMed

    Yom-Tov, Ortal; Seliktar, Dror; Bianco-Peled, Havazelet

    2015-10-01

    The use of buoyant or floating hydrogel tablets is of particular interest in the sustained release of drugs to the stomach. They have an ability to slow the release rates of drugs by prolonging their absorption window in the upper part of the gastrointestinal (GI) tract. In this study we synthesized bioactive hydrogels that have sustainable release rates for drugs in the stomach based on a hydrogel preparation technique that employs emulsifying surfactants. The emulsion gelation technique, which encapsulates oil droplets within the hydrogels during crosslinking, was used to decrease their specific gravity in aqueous environments, resulting in floating drug release depots. Properties such as swelling, buoyancy, density and drug release were manipulated by changing the polymer concentrations, surfactant percentages and the oil:polymer ratios. The relationship between these properties and the hydrogel's floating lag time was documented. The potential for this material to be used as a floating drug delivery system was demonstrated. PMID:26117764

  4. Evaluation of floating-point sum or difference of products in carry-save domain

    NASA Technical Reports Server (NTRS)

    Wahab, A.; Erdogan, S.; Premkumar, A. B.

    1992-01-01

    An architecture to evaluate a 24-bit floating-point sum or difference of products using modified sequential carry-save multipliers with extensive pipelining is described. The basic building block of the architecture is a carry-save multiplier with built-in mantissa alignment for the summation during the multiplication cycles. A carry-save adder, capable of mantissa alignment, correctly positions products with the current carry-save sum. Carry propagation in individual multipliers is avoided and is only required once to produce the final result.

  5. Discrimination of Umami Tastants Using Floating Electrode-Based Bioelectronic Tongue Mimicking Insect Taste Systems.

    PubMed

    Lee, Minju; Jung, Je Won; Kim, Daesan; Ahn, Young-Joon; Hong, Seunghun; Kwon, Hyung Wook

    2015-12-22

    We report a floating electrode-based bioelectronic tongue mimicking insect taste systems for the detection and discrimination of umami substances. Here, carbon nanotube field-effect transistors with floating electrodes were hybridized with nanovesicles containing honeybee umami taste receptor, gustatory receptor 10 of Apis mellifera (AmGr10). This strategy enables us to discriminate between l-monosodium glutamate (MSG), best-known umami tastant, and non-umami substances with a high sensitivity and selectivity. It could also be utilized for the detection of MSG in liquid food such as chicken stock. Moreover, we demonstrated the synergism between MSG and disodium 5'-inosinate (IMP) for the umami taste using this platform. This floating electrode-based bioelectronic tongue mimicking insect taste systems can be a powerful platform for various applications such as food screening, and it also can provide valuable insights on insect taste systems. PMID:26563753

  6. Influence of different types of low substituted hydroxypropyl cellulose on tableting, disintegration, and floating behaviour of floating drug delivery systems

    PubMed Central

    Diós, Péter; Pernecker, Tivadar; Nagy, Sándor; Pál, Szilárd; Dévay, Attila

    2014-01-01

    The object of the present study is to evaluate the effect of application of low-substituted hydroxypropyl cellulose (L-HPC) 11 and B1 as excipients promoting floating in gastroretentive tablets. Directly compressed tablets were formed based on experimental design. Face-centred central composite design was applied with two factors and 3 levels, where amount of sodium alginate (X1) and L-HPC (X2) were the numerical factors. Applied types of L-HPCs and their 1:1 mixture were included in a categorical factor (X3). Studied parameters were floating lag time, floating time, floating force, swelling behaviour of tablets and dissolution of paracetamol, which was used as a model active substance. Due to their physical character, L-HPCs had different water uptake and flowability. Lower flowability and lower water uptake was observed after 60 min at L-HPC 11 compared to L-HPC B1. Shorter floating times were detected at L-HPC 11 and L-HPC mixtures with 0.5% content of sodium alginate, whereas alginate was the only significant factor. Evaluating results of drug release and swelling studies on floating tablets revealed correlation, which can serve to help to understand the mechanism of action of L-HPCs in the field development of gastroretentive dosage forms. PMID:26702261

  7. Floating Loop System For Cooling Integrated Motors And Inverters Using Hot Liquid Refrigerant

    DOEpatents

    Hsu, John S [Oak Ridge, TN; Ayers, Curtis W [Kingston, TN; Coomer, Chester [Knoxville, TN; Marlino, Laura D [Oak Ridge, TN

    2006-02-07

    A floating loop vehicle component cooling and air-conditioning system having at least one compressor for compressing cool vapor refrigerant into hot vapor refrigerant; at least one condenser for condensing the hot vapor refrigerant into hot liquid refrigerant by exchanging heat with outdoor air; at least one floating loop component cooling device for evaporating the hot liquid refrigerant into hot vapor refrigerant; at least one expansion device for expanding the hot liquid refrigerant into cool liquid refrigerant; at least one air conditioning evaporator for evaporating the cool liquid refrigerant into cool vapor refrigerant by exchanging heat with indoor air; and piping for interconnecting components of the cooling and air conditioning system.

  8. Low pressure glow discharge in a system with hollow electrode at floating potential

    NASA Astrophysics Data System (ADS)

    Babinov, N. A.

    2016-01-01

    This article describes the research of the low pressure gas discharge in a system with hollow electrode at the floating potential. The main characteristic features of the discharge distinguishing it from the glow discharge with hollow cathode are described. The studied type of discharge has good perspective to use in the plasma emission systems allowing to reach high current efficiency of the ion sources.

  9. A novel floating controlled release drug delivery system prepared by hot-melt extrusion.

    PubMed

    Vo, Anh Q; Feng, Xin; Morott, Joseph T; Pimparade, Manjeet B; Tiwari, Roshan V; Zhang, Feng; Repka, Michael A

    2016-01-01

    Floating dosage forms are an important formulation strategy for drugs with a narrow absorption window and low intestinal solubility, and for localized gastric treatment. Novel floating pellets were prepared using the hot-melt extrusion (HME) technology. Uniformly foamed strands were created by liquid injection pumping and screw configuration modification. The ammonio methacrylate copolymer (Eudragit® RSPO) foaming structure was formed by a liquid-vapor phase transition inside the strand upon die exiting resulting from the sudden decrease in external pressure, vaporizing the liquid ethanol and vacating the extruded material. This generated uniform vacuous regions in the extrudate. The pellets' internal structure was investigated using scanning electron microscopy (SEM). The formulation constituents' and processing parameters' effects on the drug release profiles, floating force, and the pellets' micromeritic properties were evaluated by design of experiments: all formulations showed zero lag time and excellent floating strength, indicating immediate-floating pellet formation. The pellets' drug release profiles were controlled by multiple independent variables at different time points (⩽ 24 h). Drug loading significantly affected drug release within the first hour, the hydroxypropyl methylcellulose (HPMC) content thereafter. Understanding the variables' effects on the formulations allows for the tailoring of this delivery system to obtain various drug release profiles. PMID:26643801

  10. Formulation and evaluation of gastroretentive floating drug delivery system of dipyridamole.

    PubMed

    Jiang, Huiming; Tian, Rui; Hu, Wenjing; Jia, Yuntao; Yuan, Pei; Wang, Jiayu; Zhang, Liangke

    2015-04-01

    A multiple-unit floating alginate bead drug delivery system with prolonged stomach retention time was developed in this study. The floating alginate beads were prepared by ionic cross-linking method, using CaCO3 as the gas-forming agent. Over 92% of the beads remained floating after 9 h. In order to prepare sustained-release dosage forms of dipyridamole, the solid dispersion technique was applied using a blend of Eudragit L100 and Eudragit RLPO. Afterwards, the solid dispersions of dipyridamole were incorporated into the floating alginate beads. The drug release was modified by changing the ratio of Eudragit RLPO and Eudragit L100 in the solid dispersions. The in vivo results showed that the relative bioavailability of alginate beads was enhanced by approximately 2.52-fold compared with that of the commercial tablet. Therefore, our study illustrated the potential use of floating alginate beads combined with the solid dispersion technique for the delivery of acid-soluble compounds, such as dipyridamole. PMID:24588740

  11. On the Assimilation of Argo Float Trajectories into the Mediterranean Forecasting System

    NASA Astrophysics Data System (ADS)

    Nilsson, Jenny A. U.; Dobricic, Srdjan; Taillandier, Vincent; Poulain, Pierre-Marie; Pinardi, Nadia

    2010-05-01

    The Mediterranean Forecasting System (MFS) has been in operations for nearly a decade, and it is continuously providing analyses on a weekly basis for the region. These forecasts are of great importance as they provide local and basin-scale information of the environmental state of the sea, and are also highly useful for tracking oil spill and search-and-rescue missions. The circulation in the interior Mediterranean Sea is to a large extent characterized by meso-scale eddies, which often have proved somewhat difficult to simulate in an adequate manner due to their high temporal and spatial variability. Data assimilation is a widely used method to improve the forecast skill of operational models and, in this study, the three-dimensional variational (OceanVAR) scheme has been extended to include Argo float trajectories, with the objective to constrain and ameliorate the numerical output primarily in terms of the subsurface velocity fields. The method of implementing the float positions into the cost function is highly unique, since it uses a tangent-linear trajectory model as the observational operator. The modeled float trajectories are obtained by integration of the linearized particle advection equation during 5-day periods, corresponding to the time when the Argo floats are drifting at parking depth (350m). For the first time, basin-wide numerical experiments have been undertaken for a 3-year period (2005-2007), and it was concluded that the trajectory assimilation significately improves the simulation of Argo float trajectories based upon analyses. Indeed, statistical studies of the root-mean-square differences between the observed and analysed float positions showed that the new OceanVar scheme yields ~20% better estimates of the predicted ocean currents. It was furthermore established that the extended OceanVAR scheme does not compromise the forecast/analysis quality of the other state variables (e.g. SLAs, temperature, salinity). A notable decrease in

  12. Statistical optimization of floating pulsatile drug delivery system for chronotherapy of hypertension

    PubMed Central

    Kshirsagar, Sanjay J; Patil, Shrikant V; Bhalekar, Mangesh R

    2011-01-01

    Introduction: A pulsatile drug delivery system is characterized by a lag time that is an interval of no drug release followed by rapid drug release. The purpose of this work was to develop hollow calcium alginate beads for floating pulsatile release of valsartan intended for chronopharmacotherapy. Floating pulsatile concept was applied to increase the gastric residence of the dosage form having lag phase followed by a burst release. Materials and Methods: To overcome the limitations of various approaches for imparting buoyancy, hollow/porous beads were prepared by simple process of acid-base reaction during ionotropic crosslinking by low viscosity sodium alginate and calcium chloride as a crosslinking agent. In this study, investigation of the functionality of the sodium alginate to predict lag time and drug release was statistically analyzed using the response surface methodology (RSM). RSM was employed for designing of the experiment, generation of mathematical models and optimization study. The chosen independent variables, i.e. sodium alginate and potassium bicarbonate were optimized with a 32 full factorial design. Floating time and cumulative percentage drug release in 6 h were selected as responses. Results: Results revealed that both the independent variables are significant factors affecting drug release profile. A second-order polynomial equation fitted to the data was used to predict the responses in the optimal region. The optimized formulation prepared according to computer-determined levels provided a release profile, which was close to the predicted values. The floating beads obtained were porous (21-28% porosity), hollow with bulk density <1 and had Ft70 of 2–11 h. The floating beads provided expected two-phase release pattern with initial lag time during floating in acidic medium followed by rapid pulse release in phosphate buffer. Conclusion: The proposed mathematical model is found to be robust and accurate for optimization of time

  13. Formulation and optimization of gastric floating drug delivery system using Central composite design and its biopharmaceutical evaluation.

    PubMed

    Meka, Venkata Srikanth; Thing, Lim Kee; Gorajana, Adinarayana; Kolapalli, Venkata Ramana-Murthy

    2015-07-01

    The present work investigates the formulation and biopharmaceutical estimation of gastric floating drug delivery system (GFDDS) of propranolol HCl using semi-synthetic polymer carboxymethyl ethyl cellulose (CMEC) and a synthetic polymer polyethylene oxide (PEO). A central composite design was applied for optimization of polymer quantity (CMEC or PEO) and sodium bicarbonate concentration as independent variables. The dependent variables evaluated were: % of drug release at 1 hr (D1hr), % drug release at 3 hr (D3hr) and time taken for 95% of drug release (t95). Numerical optimization and graphical optimization were conducted to optimize the response variables. All observed responses of statistically optimized formulations were in high treaty with predicted values. Accelerated stability studies were conducted on the optimized formulations at 40 ± 2°C/75% ± 5% RH and confirm that formulations were stable. Optimized formulations were evaluated for in vivo buoyancy characterization in human volunteers and were found buoyant in gastric fluid. Gastric residence time was enhanced in the fed but not the fasted state. The optimized formulations and marketed formulation were administered to healthy human volunteers and evaluated for pharmacokinetic parameters. Mean residence time (MRT) was prolonged and AUC levels were increased for both optimized floating tablets when compared with marketed product. High relative bioavailability obtained with optimized gastric floating tablets compared to commercial formulation, indicated the improvement of bioavailability. PMID:26142528

  14. Floating in situ gelling system of acetohydroxamic acid for clearance of H. pylori.

    PubMed

    Rajinikanth, Paruvathanahalli Siddalingam; Mishra, Brahmeshwar

    2008-06-01

    The objective of this study was to develop a novel floating in situ gel system for sustained drug delivery of acetohydroxamic acid (FIGA) for eradication of Helicobacter pylori (H. pylori). The FIGA was prepared by dissolving the different concentration of gellan in deionized water at 80 degrees C. Different concentration of drug and calcium carbonate as floating agents were dispersed with stirring. In vitro results revealed that in situ gelling formulation forms rigid gels instantaneously and floated for longed period time of time in SGF pH 1.2. The formulation parameters, such as concentration of polymer, concentration of calcium carbonate, and concentration of drug, affected the in vitro drug release characteristic significantly. Absence of drug-polymer interaction was confirmed by differential scanning calorimetry analysis. The in vivo H. pylori clearance efficacy of prepared FIGA in reference to acetohydroxamic acid suspension following repeated oral administration to H. pylori-infected Mongolian gerbils was examined by microbial culture method. FIGA showed a significant anti-H. pylori effect in the in vivo gerbil model. It was noted that the required amount of acetohydroxamic acid for eradication of H. pylori was very less in FIGA than in the corresponding acetohydroxamic acid suspension. From the above results, it was concluded that the floating in situ gelling system has feasibility for forming rigid gels in the stomach and eradicated H. pylori from the gastrointestinal tract more effectively than acetohydroxamic acid suspension because of the prolonged gastrointestinal residence time of the formulation. PMID:18568907

  15. Garden Banks 388 subsea production control system

    SciTech Connect

    Goggans, T.; MacNeill, J.; Blincow, M.

    1995-12-31

    This paper discusses the design, analysis and performance requirements of an electrohydraulic production control system for a 24 well deepwater development controlled from a Floating Production Facility (FPF) in the Gulf of Mexico. The controls include not only topside FPF installed equipment, but subsea template and tree mounted equipment, including control umbilicals.

  16. Stability Analysis of a Turbocharger Rotor System Supported on Floating Ring Bearings

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Shi, Z. Q.; Zhen, D.; Gu, F. S.; Ball, A. D.

    2012-05-01

    The stability of a turbocharger rotor is governed by the coupling of rotor dynamics and fluid dynamics because the high speed rotor system is supported on a pair of hydrodynamic floating ring bearings which comprise of inner and outer fluid films in series. In order to investigate the stability, this paper has developed a finite element model of the rotor system with consideration of such exciting forces as rotor imbalance, hydrodynamic fluid forces, lubricant feed pressure and dead weight. The dimensionless analytical expression of nonlinear oil film forces in floating ring bearings have been derived on the basis of short bearing theory. Based on numerical simulation, the effects of rotor imbalance, lubricant viscosity, lubricant feed pressure and bearing clearances on the stability of turbocharger rotor system have been studied. The disciplines of the stability of two films and dynamic performances of rotor system have been provided.

  17. Monitoring natural and artificial radioactivity enhancement in the Aegean Sea using floating measuring systems.

    PubMed

    Tsabaris, C

    2008-11-01

    In the present work, the enhancement of radioactivity due to rainfall in the Aegean Sea using floating measuring systems was observed and quantified. The data were acquired with a NaI underwater detection system, which was installed on a floating measuring system at a depth of 3m. The results of natural and artificial radioactivity are discussed taking into account the rainfall intensity and wind direction. The activity concentration of (214)Bi increased up to (991+/-102)Bq/m(3) after strong rainfall in the North Aegean Sea in winter (humid period) with east wind direction. On other hand, the maximum activity concentration reached the level of (110+/-10)Bq/m(3) in summer (dry period) during south winds. PMID:18495486

  18. Net community production at Ocean Station Papa observed with nitrate and oxygen sensors on profiling floats

    NASA Astrophysics Data System (ADS)

    Plant, Joshua N.; Johnson, Kenneth S.; Sakamoto, Carole M.; Jannasch, Hans W.; Coletti, Luke J.; Riser, Stephen C.; Swift, Dana D.

    2016-06-01

    Six profiling floats equipped with nitrate and oxygen sensors were deployed at Ocean Station P in the Gulf of Alaska. The resulting six calendar years and 10 float years of nitrate and oxygen data were used to determine an average annual cycle for net community production (NCP) in the top 35 m of the water column. NCP became positive in February as soon as the mixing activity in the surface layer began to weaken, but nearly 3 months before the traditionally defined mixed layer began to shoal from its winter time maximum. NCP displayed two maxima, one toward the end of May and another in August with a summertime minimum in June corresponding to the historical peak in mesozooplankton biomass. The average annual NCP was determined to be 1.5 ± 0.6 mol C m-2 yr-1 using nitrate and 1.5 ± 0.7 mol C m-2 yr-1 using oxygen. The results from oxygen data proved to be quite sensitive to the gas exchange model used as well as the accuracy of the oxygen measurement. Gas exchange models optimized for carbon dioxide flux generally ignore transport due to gas exchange through the injection of bubbles, and these models yield NCP values that are two to three time higher than the nitrate-based estimates. If nitrate and oxygen NCP rates are assumed to be related by the Redfield model, we show that the oxygen gas exchange model can be optimized by tuning the exchange terms to reproduce the nitrate NCP annual cycle.

  19. Experimental Investigation of the Power Generation Performance of Floating-Point Absorber Wave Energy Systems: Preprint

    SciTech Connect

    Li, Y.; Yu, Y.; Epler, J.; Previsic, M.

    2012-04-01

    The extraction of energy from ocean waves has gained interest in recent years. The floating-point absorber (FPA) is one of the most promising devices among a wide variety of wave energy conversion technologies. Early theoretical studies mainly focused on understanding the hydrodynamics of the system and on predicting the maximum power that could be extracted by a heaving body. These studies evolve from the investigation of floating-body interactions in offshore engineering and naval architecture disciplines. To our best knowledge, no systematic study has been reported about the investigation of the power generation performance of an FPA with a close-to-commercial design. A series of experimental tests was conducted to investigate the power extraction performance of an FPA system.

  20. Numerical simulation of the spreading dynamic responses of the multibody system with a floating base

    NASA Astrophysics Data System (ADS)

    Jiang, Zhaobing; Shao, Luzhong; Shao, Fei

    2015-07-01

    To simulate the dynamic responses of the multibody system with a floating base when the upper parts spread with a certain sequence and relative speed, the homogeneous matrix method is employed to model and simulate a four-body system with a floating base and the motions are analyzed when the upper parts are spread sequentially or synchronously. The rolling, swaying and heaving temporal variations are obtained when the multibody system is under the conditions of the static water along with the wave loads and the mean wind loads or the single pulse wind loads, respectively. The moment variations of each joint under the single pulse wind load are also gained. The numerical results showed that the swaying of the floating base is almost not influenced by the spreading time or form when the upper parts spread sequentially or synchronously, while the rolling and the heaving mainly depend on the spreading time and forms. The swaying and heaving motions are influenced significantly by the mean wind loads. The single pulse wind load also has influences on the dynamic responses. The torque of joint 3 and joint 4 in the single pulse wind environment may be twice that in the windless environment when the system spreads with 60 s duration.

  1. A floating multiparticulate system for ofloxacin based on a multilayer structure: In vitro and in vivo evaluation.

    PubMed

    Zhang, Chungang; Xu, Ming; Tao, Xiaoguang; Tang, Jingya; Liu, Zitong; Zhang, Yu; Lin, Xia; He, Haibing; Tang, Xing

    2012-07-01

    The purpose of this research was to develop a novel gastroretentive multiparticulate system with floating ability. This system was designed to provide drug-loaded pellets coated with three successive coatings-the retarding film (ethyl cellulose), the effervescent layer (sodium bicarbonate) and the gas-entrapped polymeric membrane (Eudragit RL 30D). The floating pellets were evaluated for SEM, floating characteristic parameters, in vitro release and bioavailability in New Zealand rabbits. The zero-order release theory model is designed to interpret the release processes. Due to the swelling property, high flexibility and high water permeability, Eudragit RL 30D was used as a gas-entrapped polymeric membrane. The obtained pellets exhibit excellent floating ability and release characteristics. Analysis of the release mechanism showed a zero-order release for the first 8h because of the osmotic pressure of the saturated solution inside of the membrane, which was in accordance with that predicted. Abdominal X-ray images showed that the gastroretention period of the floating barium sulfate-labeled pellets was no less than 6h. The relative bioavailability of the floating pellets compared with reference tablets was 113.06 ± 23.83%. All these results showed that the floating pellets are a feasible approach for the gastroretentive drug delivery system. PMID:22525085

  2. Interpretation of IEEE-854 floating-point standard and definition in the HOL system

    NASA Technical Reports Server (NTRS)

    Carreno, Victor A.

    1995-01-01

    The ANSI/IEEE Standard 854-1987 for floating-point arithmetic is interpreted by converting the lexical descriptions in the standard into mathematical conditional descriptions organized in tables. The standard is represented in higher-order logic within the framework of the HOL (Higher Order Logic) system. The paper is divided in two parts with the first part the interpretation and the second part the description in HOL.

  3. A system architecture for long duration free floating flight for military applications

    SciTech Connect

    Epley, L.E. )

    1990-08-31

    Accessibility is today's space frontier. Our need for wide-band global communications, earth imaging an sensing, atmospheric measurements and military reconnaissance is endless but growing dependence on space-based systems raises concerns about potential vulnerability. Military commanders want space assets more accessible and under direct local control. As a result, a robust and low cost access to space-like capability has become a national priority. Buoyant vehicles, free floating in the middle stratosphere could provide the kind of cost effective access to space-like capability needed for a verity of missions. These vehicles are inexpensive, invisible and easily launched. Developments in payload electronics, atmospheric wind modeling and materials combined with ever-improving communications and navigation infrastructure are making balloon-borne concepts more attractive. The fundamental question is whether a free floating balloon, used in a pseudo-satellite role, has value in a military system. Flight tests are ongoing under NASA sponsorship. Following these tests NASA intends to use the vehicles for research in the Antarctic. The concept is being reviewed by other agencies interested in stratospheric research. We believe that LDFFF systems have applications in areas of communications, surveillance and other traditional satellite missions. Dialogue with the broader community of space users is needed to expand the applications. This report reviews the status of the recent flight tests and presents an overview of the concept of Long Duration Free Floating Flight for military applications. 12 refs., 13 figs.

  4. Stability and chaotification of vibration isolation floating raft systems with time-delayed feedback control.

    PubMed

    Li, Y L; Xu, D L; Fu, Y M; Zhou, J X

    2011-09-01

    This paper presents a systematic study on the stability of a two-dimensional vibration isolation floating raft system with a time-delayed feedback control. Based on the generalized Sturm criterion, the critical control gain for the delay-independent stability region and critical time delays for the stability switches are derived. The critical conditions can provide a theoretical guidance of chaotification design for line spectra reduction. Numerical simulations verify the correctness of the approach. Bifurcation analyses reveal that chaotification is more likely to occur in unstable region defined by these critical conditions, and the stiffness of the floating raft and mass ratio are the sensitive parameters to reduce critical control gain. PMID:21974650

  5. The Scale Effect in Towing Tests with Airplane-float Systems

    NASA Technical Reports Server (NTRS)

    Schmidt, Rudolph

    1937-01-01

    The present report includes a description of the making of three-component measurements on a full-size float mounted on an actual airplane and the comparison of the results with those from two models of the same form but of different size which had been tested in the towing tank. The purpose of the comparison is to determine the effect of the Reynolds Number on the results of model tank tests. Following a brief discussion of previous tests intended to elucidate the problem of scale effect on float systems and a description of the testing equipment, the choice of the reference quantities to be used in the comparison is discussed. The selection of load, speed, and trim as a basis of comparison seems best suited to the practical operation of making this comparison. The quantities affected by scale are then: resistance, trimming moment, and their derivatives; planing number (resistance/weight on water); and position of center of pressure.

  6. Experiment study of dynamics response for wind turbine system of floating foundation

    NASA Astrophysics Data System (ADS)

    Tang, You-gang; Song, Kai; Wang, Bin

    2015-12-01

    The floating foundation is designed to support a 1.5 MW wind turbine in 30 m water depth. With consideration of the viscous damping of foundation and heave plates, the amplitude-frequency response characteristics of the foundation are studied. By taking into account the elastic effect of blades and tower, the classic quasi-steady blade-element/momentum (BEM) theory is used to calculate the aerodynamic elastic loads. A coupled dynamic model of the turbine-foundationmooring lines is established to calculate the motion response of floating foundation under Kaimal wind spectrum and regular wave by using the FAST codes. The model experiment is carried out to test damping characteristics and natural motion behaviors of the wind turbine system. The dynamics response is tested by considering only waves and the joint action of wind and waves. It is shown that the wind turbine system can avoid resonances under the action of wind and waves. In addition, the heave motion of the floating foundation is induced by waves and the surge motion is induced by wind. The action of wind and waves is of significance for pitch.

  7. Formulation and evaluation of atenolol floating bioadhesive system using optimized polymer blends

    PubMed Central

    Siddam, Haritha; Kotla, Niranjan G.; Maddiboyina, Balaji; Singh, Sima; Sunnapu, Omprakash; Kumar, Anil; Sharma, Dinesh

    2016-01-01

    Introduction: Oral sustained release gastro retentive dosage forms offer several advantages for drugs having absorption from the upper gastrointestinal tract to improve the bioavailability of medications which have narrow absorption window. The aim of the study was to develop a floating bioadhesive drug delivery system exhibiting a unique combination of floatation and bioadhesion to prolong the residence in the stomach using atenolol as a model drug. Methods: Prior to compression, polymeric blend(s) were evaluated for flow properties. The tablets were prepared by direct compression method using bioadhesive polymer like Carbopol 934P and hydrophilic polymers like HPMC K4M, HPMC K15M, and HPMC K100M. The prepared tablets were evaluated for physical characteristics, bioadhesive strength, buoyancy lag time, swelling index and in vitro drug release studies. Results: The mean bioadhesive strength was found to be in the range of 16.2 to 52.1 gm. The optimized blend (F11) showed 92.3% drug releases after 24 hrs. Whilst, increase in concentration of carbopol 934P, bioadhesive strength and swelling index was increased with slow release. The n values of optimized formulations were found in the range of 0.631-0.719 indicating non-fickian anomalous type transport mechanism. Conclusion: The study aided in developing an ideal once-a-day gastro retentive floating drug delivery system with improved floating, swelling and bioadhesive characteristics with better bioavailability. PMID:27051631

  8. Physical characterizations and sustained release profiling of gastroretentive drug delivery systems with improved floating and swelling capabilities.

    PubMed

    Chen, Ying-Chen; Ho, Hsiu-O; Lee, Tzu-Yu; Sheu, Ming-Thau

    2013-01-30

    The aim was to develop gastroretentive drug delivery systems (GRDDSs) by combining floating and swelling. GRDDS tablets formulated with hydroxyethylcellulose (HEC), chitosan (CS) and sodium bicarbonate (SB) for evaluating floating capacity (floating lag time and duration) and swelling characteristics. CS was used because it was swellable in acidic media and biocompatible. Losartan was incorporated into the optimized formulations for sustained release profiling. Results demonstrated that for those formulations at HEC:CS ratio of 5:5 containing CS, both the floating lag time and floating duration were optimal and reached the preferred swelling effect and sustain for 24h. Adding SB improved the floating capabilities for all ratios of HEC:CS, but reduced the swelling ability for those formulations containing a higher portion of low viscosity grade CS. Sustained release profiles for losartan in those formulations were achievable, using all viscosity grades of CS at all examined HEC:CS ratios; however, it is more adjustable at different HEC:CS ratios when using a lower viscosity grade of CS. Optimized GRDDS formulations for losartan composed of an equivalent ratio of HEC to CS with 20mg SB resulted in the tablets floating for more than 16 h and an adjustable sustained release profile. PMID:23237874

  9. Floating Ultrasonic Transducer Inspection System and Method for Nondestructive Evaluation

    NASA Technical Reports Server (NTRS)

    Zalameda, Joseph N. (Inventor); Johnston, Patrick H. (Inventor)

    2016-01-01

    A method for inspecting a structural sample using ultrasonic energy includes positioning an ultrasonic transducer adjacent to a surface of the sample, and then transmitting ultrasonic energy into the sample. Force pulses are applied to the transducer concurrently with transmission of the ultrasonic energy. A host machine processes ultrasonic return pulses from an ultrasonic pulser/receiver to quantify attenuation of the ultrasonic energy within the sample. The host machine detects a defect in the sample using the quantified level of attenuation. The method may include positioning a dry couplant between an ultrasonic transducer and the surface. A system includes an actuator, an ultrasonic transducer, a dry couplant between the transducer the sample, a scanning device that moves the actuator and transducer, and a measurement system having a pulsed actuator power supply, an ultrasonic pulser/receiver, and a host machine that executes the above method.

  10. Development of gastroretentive metronidazole floating raft system for targeting Helicobacter pylori.

    PubMed

    Abou Youssef, Nancy Abdel Hamid; Kassem, Abeer Ahmed; El-Massik, Magda Abd Elsamea; Boraie, Nabila Ahmed

    2015-01-01

    The study demonstrates the feasibility of prolonging gastric residence time and release rate of metronidazole (Mz) by preparing floating raft system (FRS) using ion-sensitive in situ gel forming polymers. FRSs contained 3, 4, 5 and 0.5, 0.75, 1% w/v sodium alginate (Alg) and gellan gum (G), respectively, 0.25% w/v sodium citrate and calcium carbonate (C). Lipids: glyceryl mono stearate (GMS), Precirol(®) and Compritol(®) were incorporated into G-based formulations (G1%C1%). Mz:lipid ratio was 1:1, except for Mz:GMS, ratios of 1:1.5 and 1:2 were also investigated. Buoyancy, gelation capacity and viscosity parameters were evaluated. Drug release and kinetics for selected formulae were examined. The selected lipid containing formula was subjected to an accelerated stability testing. Alg4%C2% FRS exhibited short gelation lag time (3s), long duration (>24h), floating lag time 1m in and duration >24h, and a reliable sustained drug release (MDT 6h). Gellan gum FRSs achieved successful floating gastroretention, but failed to achieve the required gelation capacity. Incorporation of GMS (Mz:GMS 1:1) enhanced the gelation lag time and duration (6s and >24h, respectively), keeping sustained drug release and formulation stability. The improved characteristics of the selected FRS make them excellent candidates for gastric targeting to eradicate Helicobacter pylori. PMID:25843757

  11. Formulation and evaluation of gastroretentive microballoons containing baclofen for a floating oral controlled drug delivery system.

    PubMed

    Dube, T S; Ranpise, N S; Ranade, A N

    2014-01-01

    The objective of the present study was to fabricate and evaluate a multiparticulate oral gastroretentive dosage form of baclofen characterized by a central large cavity (hollow core) promoting unmitigated floatation with practical applications to alleviate the signs and symptoms of spasticity and muscular rigidity. Solvent diffusion and evaporation procedure were applied to prepare floating microspheres with a central large cavity using various combinations of ethylcellulose (release retardant) and HPMC K4M (release modifier) dissolved in a mixture of dichloromethane and methanol (2:1). The obtained microspheres (700-1000 µm) exhibit excellent floating ability (86 ± 2.00%) and release characteristics with entrapment efficiency of 95.2 ± 0.32%. Microspheres fabricated with ethylcellulose to HPMC K4M in the ratio 8.5:1.5 released 98.67% of the entrapped drug in 12 h. Muscle relaxation caused by baclofen microspheres impairs the rotarod performance for more than 12 h. Abdominal X-ray images showed that the gastroretention period of the floating barium sulfate- labeled microspheres was no less than 10 h. The buoyant baclofen microspheres provide a promising gastroretentive drug delivery system to deliver baclofen in spastic patients with a sustained release rate. PMID:24730440

  12. Ability of floating platforms and tankers to operate in the Hibernia environment

    SciTech Connect

    Mcintyre, N.F.

    1981-01-01

    The ability of floating platforms and tankers to operate in the Hibernia environment is discussed. The basic environmental difference between the fixed and floating concept is that the floating systems are unable to withstand impact from heavy ice floes or large icebergs. Therefore, they are designed to utilize safe, reliable quick-disconnect systems, which permit them to evacuate the area when encroaching ice presents a potential hazard. Floating production systems being considered for Hibernia involve ship-type vessels, conventional semisubmersibles, and some form of floating storage and loading facility.

  13. Application of a floating point systems AP190L array processor to finite element analysis

    SciTech Connect

    Young, R.C.

    1982-04-01

    This report discusses the implementation of a finite element program on a Floating Point Systems AP190L array processor attached to a Univac 1182 host computer. The array processor was used to perform all calculations on the global system of linear equations including matrix assembly, matrix factoring and vector solution. A large scratch disk was attached directly to the array processor for storing the factored matrix. The remaining calculations, including data preparation, element matrix formation, stress integration and output display were performed by the host computer.

  14. Float Zone Workshop

    NASA Technical Reports Server (NTRS)

    Naumann, R. J.

    1980-01-01

    A summary of the Analytical Float Zone Experiment System (AFZES) concept is presented. The types of experiments considered for such a facility are discussed. Reports from various industrial producers and users of float zone material are presented. Special emphasis is placed on state-of-the-art developments in low gravity manufacturing and their applications to space processing.

  15. Tech-IA floating system introduced in urban wastewater treatment plants in the Veneto region - Italy.

    PubMed

    Mietto, Anna; Borin, Maurizio; Salvato, Michela; Ronco, Paolo; Tadiello, Nicola

    2013-01-01

    The performance of three integrated wetland treatment plants (horizontal sub-surface flow (h-SSF) and floating treatment wetland (FTW) with differentiated primary treatments) designed for treating domestic wastewater was investigated, monitoring total (TN), nitrate (NO3-N), nitrite (NO2-N) and ammonia nitrogen (NH4-N), total (TP) and phosphate phosphorus (PO4-P), chemical (COD) and biological oxygen demand (BOD5), and dissolved oxygen (DO) at the inlet and outlet of each wetland section from February 2011 to June 2012. Sediments settled in the FTW were collected and analyzed. The growth of plants in each system was also monitored, observing their general conditions. The chemical-physical characteristics of the pretreated domestic wastewater depended on the primary treatment installed. During the monitoring period we observed different reduction performance of the wetland sector in the three sites. In general, the wetland systems demonstrated the capacity to reduce TN, COD, BOD5 and Escherichia coli, whereas NO3-N and NH4-N removal was strictly influenced by the chemical conditions, in particular DO concentration, in the h-SSF and FTW. Vegetation (Phragmites australis, Alnus glutinosa and Salix eleagnos) was well established in the h-SSF as well as in the floating elements (Iris pseudacorus), although there were some signs of predation. FTW is a relatively novel wetland system, so the results obtained from this study can pave the way for the application of this technology. PMID:24037167

  16. Influence of motion coupling and nonlinear effects on parametric roll for a floating production storage and offloading platform

    PubMed Central

    Greco, M.; Lugni, C.; Faltinsen, O. M.

    2015-01-01

    Occurrence and features of parametric roll (PR) on a weather-vaning floating production storage and offloading (FPSO) platform with a turret single-point mooring-line system are examined. The main focus is on the relevance of motions coupling and nonlinear effects on this phenomenon and on more general unstable conditions as well as on the occurrence and severity of water on deck. This work was motivated by recent experiments on an FPSO model without mooring systems highlighting the occurrence of parametric resonance owing to roll–yaw coupling. A three-dimensional numerical hybrid potential-flow seakeeping solver was able to capture this behaviour. The same method, extended to include the mooring lines, is adopted here to investigate the platform behaviour for different incident wavelengths, steepnesses, headings, locations of the turret and pretensions. From the results, sway and yaw tend to destabilize the system, also bringing chaotic features. The sway–roll–yaw coupling widens the existence region of PR resonance and increases PR severity; it also results in a larger amount of shipped water, especially at smaller wavelength-to-ship length ratio and larger steepness. The chaotic features are excited when a sufficiently large yaw amplitude is reached. Consistently, a simplified stability analysis showed the relevance of nonlinear-restoring coefficients, first those connected with the sway–yaw coupling then those associated with the roll–yaw coupling, both destabilizing. From the stability analysis, the system is unstable for all longitudinal locations of the turret and pre-tensions examined, but the instability weakens as the turret is moved forward, and the pre-tension is increased. The use of a suitable dynamic-positioning system can control the horizontal motions, avoiding the instability. PMID:25512590

  17. Influence of motion coupling and nonlinear effects on parametric roll for a floating production storage and offloading platform.

    PubMed

    Greco, M; Lugni, C; Faltinsen, O M

    2015-01-28

    Occurrence and features of parametric roll (PR) on a weather-vaning floating production storage and offloading (FPSO) platform with a turret single-point mooring-line system are examined. The main focus is on the relevance of motions coupling and nonlinear effects on this phenomenon and on more general unstable conditions as well as on the occurrence and severity of water on deck. This work was motivated by recent experiments on an FPSO model without mooring systems highlighting the occurrence of parametric resonance owing to roll-yaw coupling. A three-dimensional numerical hybrid potential-flow seakeeping solver was able to capture this behaviour. The same method, extended to include the mooring lines, is adopted here to investigate the platform behaviour for different incident wavelengths, steepnesses, headings, locations of the turret and pretensions. From the results, sway and yaw tend to destabilize the system, also bringing chaotic features. The sway-roll-yaw coupling widens the existence region of PR resonance and increases PR severity; it also results in a larger amount of shipped water, especially at smaller wavelength-to-ship length ratio and larger steepness. The chaotic features are excited when a sufficiently large yaw amplitude is reached. Consistently, a simplified stability analysis showed the relevance of nonlinear-restoring coefficients, first those connected with the sway-yaw coupling then those associated with the roll-yaw coupling, both destabilizing. From the stability analysis, the system is unstable for all longitudinal locations of the turret and pre-tensions examined, but the instability weakens as the turret is moved forward, and the pre-tension is increased. The use of a suitable dynamic-positioning system can control the horizontal motions, avoiding the instability. PMID:25512590

  18. Lagrangian floats as sea floor imaging platforms

    NASA Astrophysics Data System (ADS)

    Roman, Chris; Inglis, Gabrielle; McGilvray, Bryan

    2011-10-01

    There is a persistent need for high resolution photographic images of the sea floor and associated biota for marine habitat classification and fisheries stock assessment. This paper presents a novel low cost Lagrangian imaging platform that offers high quality images with reduced operational demands in comparison to existing methodologies such as diver surveys, drop cameras, ship towed systems and dedicated remote or autonomous underwater vehicles. The platform consists of a recently developed bottom following Lagrangian float fit with down looking stereo cameras and strobe lighting. The float can use active ballasting to perform constant altitude photographic drift surveys in coastal waters over varying bathymetry. Images from the float can be used to create large photomosaics, stereographic bathymetry estimates and image-derived current measurements. Test data are presented to demonstrate the operation of the Lagrangian float and summarize the data products.

  19. A three-axis high-resolution capacitive tactile imager system based on floating comb electrodes

    NASA Astrophysics Data System (ADS)

    Surapaneni, R.; Guo, Q.; Xie, Y.; Young, D. J.; Mastrangelo, C. H.

    2013-07-01

    We present the design, fabrication and testing of a high-resolution 169-sensing cell capacitive flexible tactile imager (FTI) for normal and shear stress measurement as an auxiliary sensor for robotic grippers and gait analysis. The FTI consists of a flexible high-density array of normal stress and two-dimensional shear stress sensors fabricated using microelectromechanical systems (MEMS) and flexible printed circuit board (FPCB) techniques. The drive/sense lines of the FTI are realized using FPCB whereas the floating electrodes (Au) are patterned on a compressible PDMS layer spin coated on the FPCB layer. The use of unconnected floating electrodes significantly improves the reliability of traditional quad-electrode contact sensing devices by eliminating the need for patterning electrical wiring on PDMS. When placed at the heel of a boot, this FTI senses the position and motion of the line of contact with the ground. Normal stress readouts are obtained from the net capacitance of the cell and the shear-sense direction is determined by the amount of asymmetric overlap of the floating combs with respect to the bottom electrodes. The FTI is characterized using a high-speed switched-capacitor circuit with a 12-bit resolution at full frame rates of 100 Hz (˜0.8 Mb s-1) capable of resolving a displacement as low as 60 µm. The FTI and the readout circuitry contribute to a noise/interference level of 5 mV and the sensitivity of normal and shear stress for the FTI is 0.38 MPa-1 and 79.5 GPa-1 respectively.

  20. Development and in vitro characterization of floating sustained-release drug delivery systems of polyphenols.

    PubMed

    Rosenzweig, Ohad; Lavy, Eran; Gati, Irith; Kohen, Ron; Friedman, Michael

    2013-01-01

    The aim of this study was to develop and characterize floating stomach-retentive matrix tablets that will deliver polyphenols in a controlled release manner. The tablets were prepared by direct compression. A number of polymers were examined and egg albumin was chosen in light of a better performance in terms of floating behavior and decomposition time. Dissolution studies for three representative polyphenols loaded into a number of formulations were performed using the "f₂" factor in order to compare release profiles of different polyphenols and formulations. The release data showed a good fit into the power law equation and zero-order kinetics has been determined for some of the systems. Erosion and textural analysis studies revealed that higher concentration of egg albumin results in a higher gel strength that is less susceptible to erosion, potentially leading to a prolonged delivery time of drug. The ability of egg albumin-based tablets to resist high mechanical forces was also determined, while comparison to cellulose-derived polymers revealed that the latter have a much lower ability to resist the same forces. The developed delivery system has the potential to increase the efficacy of the therapy for various pathological stomach conditions and to improve patient compliance. PMID:23730744

  1. Development of floating plastic media filtration system for water treatment and wastewater reuse.

    PubMed

    Chiemchaisri, C; Panchawaranon, C; Rutchatanunti, S; Kludpiban, A; Ngo, H H; Vigneswaran, S

    2003-01-01

    Floating plastic media coupled with sand filtration system was applied for treating surface water and secondary effluent from municipal sewage treatment plant. The system employed floating plastic media for the removal of suspended solids in surface water and precipitated phosphorus from secondary effluent of sewage treatment plant. Sand filtration was then used to remove further the suspended solids. For the purposes of wastewater reuse, a zeolite layer was used instead of sand filter to absorb ammonium nitrogen. Application of system for surface water treatment suggested appropriate filtration rate of 5 m3/m2 h. Polyaluminum chloride was found to be the best coagulant with an appropriate plastic and sand bed depth of 40 cm. The system could produce average effluent turbidity and suspended solids of 0.71 NTU and 0.94 mg/L respectively. Average turbidity and suspended solids removal efficiencies were 96.26% and 95.48% with low headloss development of 40.4 cm at the end of 6 h operation period. When applying 1.50 m. floating plastic media bed for the treatment of synthetic raw water, short and long-term turbidity removal efficiencies were 96.79-97.72% and 81.81-94.61% for raw water containing turbidity of 20 and 40 NTU. It could produce the effluent with turbidity less than 5NTU while having less than 1.0 m. headloss. The system was also applied for the secondary effluent treatment. An optimum filtration rate of 5 m3/m2 h was obtained when using plastic and sand bed depth of 60 and 20cm under direct filtration mode. Average turbidity removal was 60.3% and 59.6% after 6 and 48 h of operation. It was also found that 1 m3/m2 h filtration rate and 50:30 cm of plastic:zeolite bed could be used to achieve both ammonium nitrogen and phosphate removal. Suspended solids, turbidity, BOD5, NH4+, and PO4(3-) removal efficiencies were 91.9, 94.6, 95.4, 97.3, and 99.5% respectively after 24 h. As a result, the effluent from the system had average NH4+ and PO4(3-) of 0.5 mg N

  2. Statistical optimization of ranitidine HCl floating pulsatile delivery system for chronotherapy of nocturnal acid breakthrough.

    PubMed

    Roy, Pallab; Shahiwala, Aliasgar

    2009-06-28

    Present work conceptualizes a specific technology, based on combining floating and pulsatile principles to develop drug delivery system, intended for chronotherapy in nocturnal acid breakthrough. This approach will be achieved by using a programmed delivery of ranitidine hydrochloride from a floating tablet with time-lagged coating. In this study, investigation of the functionality of the outer polymer coating to predict lag time and drug release was statistically analyzed using the response surface methodology (RSM). RSM was employed for designing of the experiment, generation of mathematical models and optimization study. The chosen independent variables, i.e. percentage weight ratios of ethyl cellulose to hydroxypropyl methyl cellulose in the coating formulation and coating level (% weight gain) were optimized with a 3(2) full factorial design. Lag time prior to drug release and cumulative percentage drug release in 7h were selected as responses. Results revealed that both, the coating composition and coating level, are significant factors affecting drug release profile. A second-order polynomial equation fitted to the data was used to predict the responses in the optimal region. The optimized formulation prepared according to computer-determined levels provided a release profile, which was close to the predicted values. The proposed mathematical model is found to be robust and accurate for optimization of time-lagged coating formulations for programmable pulsatile release of ranitidine hydrochloride, consistent with the demands of nocturnal acid breakthrough. PMID:19491027

  3. Wide-viewing-angle floating 3D display system with no 3D glasses

    NASA Astrophysics Data System (ADS)

    Dolgoff, Eugene

    1998-04-01

    Previously, the author has described a new 3D imaging technology entitled 'real depth' with several different configurations and methods of implantation. Included were several methods to 'float' images in free space. Viewers can pass their hands through the image or appear to hold it in their hands. Most implementations provide an angle of view of approximately 45 degrees. The technology produces images at different depths from any display, such as CRT and LCD, for television, computer, projection, and other formats. Unlike stereoscopic 3D imaging, no glasses, headgear or other viewing aids are used. In addition to providing traditional depth cues, such as perspective and background images occlusion, the technology also provides both horizontal and vertical binocular parallax producing visual accommodation and convergence which coincide. Consequently, viewing these images do not produce headaches, fatigue, or eyestrain, regardless of how long they are viewed. A method was also proposed to provide a floating image display system with a wide angle of view. Implementation of this design proved problematic, producing various image distortions. In this paper the author discloses new methods to produce aerial images with a wide angel of view and improved image quality.

  4. Interpolation of On-Line Data of the Argo Float System for Data Assimilation in the World Ocean Circulation Model

    NASA Astrophysics Data System (ADS)

    Zakharova, N. B.; Lebedev, S. A.

    2010-12-01

    For many years parameters of the World ocean state were measured by traditional contact methods that lacked in efficiency and the ability to measure temperature much beneath the surface. The ARGO float system involves both contact and distance ocean parameters measure methods. Sea temperature and salinity profiles are measured by contact methods, but data communication is made using satellites. Therefore, the ARGO float system has added efficiency and greater reliability to ocean parameters measurements. Interpolation and extrapolation methods of input information are important among numerical mathematical methods used for solving data assimilation problems. Thus the development of such algorithms and programs based on up-to-date approaches is a timely problem.

  5. Design and evaluation of an innovative floating and bioadhesive multiparticulate drug delivery system based on hollow structure.

    PubMed

    Zhang, Chungang; Tang, Jingya; Liu, Dechun; Li, Xuetao; Cheng, Lan; Tang, Xing

    2016-04-30

    In this study a gastric-retentive delivery system was prepared by a novel method which is reported here for the first time. An innovative floating and bioadhesive drug delivery system with a hollow structure was designed and prepared. The floating and bioadhesive drug delivery system was composed of a hollow spherical shell, a waterproof layer (Stearic acid), a drug layer (Ofloxacin), a release retarding film (the novel blended coating materials) and a bioadhesive layer (Carbomer 934P) prepared by using a liquid multi-layering process. A novel blended coating material was designed and investigated to solve the problem of the initial burst release of the formulation and the release mechanism of the novel material was analyzed in this study. The optimized formulation provided the sustained release characteristic and was able to float for 24h. The SEM cross-section images showed that the particulates were hollow with a spherical shell. X-ray images and pharmacokinetic studies (Frel = 124.1 ± 28.9%) in vivo showed that the gastric-retentive delivery system can be retained in the stomach for more than 6h. The floating and bioadhesive particulate drug delivery system based on a hollow structure with a dual function presented here is a viable alternative to other for gastroretentive drug delivery system. PMID:26943975

  6. Design and statistical optimization of an effervescent floating drug delivery system of theophylline using response surface methodology.

    PubMed

    Srikanth Meka, Venkata; Ee Li, Chew; Sheshala, Ravi

    2016-03-01

    The aim of this research was to formulate effervescent floating drug delivery systems of theophylline using different release retarding polymers such as ethyl cellulose, Eudragit® L100, xanthan gum and polyethylene oxide (PEO) N12K. Sodium bicarbonate was used as a gas generating agent. Direct compression was used to formulate floating tablets and the tablets were evaluated for their physicochemical and dissolution characteristics. PEO based formulations produced better drug release properties than other formulations. Hence, it was further optimized by central composite design. Further subjects of research were the effect of formulation variables on floating lag time and the percentage of drug released at the seventh hour (D7h). The optimum quantities of PEO and sodium bicarbonate, which had the highest desirability close to 1.0, were chosen as the statistically optimized formulation. No interaction was found between theophylline and PEO by Fourier Transformation Infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) studies. PMID:26959542

  7. Experimental and numerical investigation of the roll motion behavior of a floating liquefied natural gas system

    NASA Astrophysics Data System (ADS)

    Zhao, WenHua; Yang, JianMin; Hu, ZhiQiang; Xiao, LongFei; Peng, Tao

    2013-03-01

    The present paper does an experimental and numerical investigation of the hydrodynamic interaction and the response of a single point turret-moored Floating Liquefied Natural Gas (FLNG) system, which is a new type of floating LNG (Liquid Natural Gas) platform that consists of a ship-type FPSO hull equipped with LNG storage tanks and liquefaction plants. In particular, this study focuses on the investigation of the roll response of FLNG hull in free-decay motions, white noise waves and also in irregular waves. Model tests of the FLNG system in 60%H filling condition excited by both white noise waves and irregular waves combined with steady wind and current have been carried out. Response Amplitude Operators (RAOs) and time histories of the responses are obtained for sway, roll and yaw motions. Obvious Low Frequency (LF) components of the roll motions are observed, which may be out of expectation. To facilitate the physical understanding of this phenomenon, we filter the roll motions at the period of 30 s into two parts: the Wave Frequency (WF) motions and the Low Frequency (LF) motions respectively. The results indicate that the LF motions are closely related to the sway and yaw motions. Possible reasons for the presence of the LF motions of roll have been discussed in detail, through the comparison with the sway and yaw motions. As for the numerical part, the simulation of the modeled case is conducted with the help of the software SESAM®. A good agreement between experiments and calculations is reported within the scope of trends. However, the numerical simulations should be further improved for the prediction of the FLNG system in the heading sea.

  8. Floating Chip Mounting System Driven by Repulsive Force of Permanent Magnets for Multiple On-Site SPR Immunoassay Measurements

    PubMed Central

    Horiuchi, Tsutomu; Tobita, Tatsuya; Miura, Toru; Iwasaki, Yuzuru; Seyama, Michiko; Inoue, Suzuyo; Takahashi, Jun-ichi; Haga, Tsuneyuki; Tamechika, Emi

    2012-01-01

    We have developed a measurement chip installation/removal mechanism for a surface plasmon resonance (SPR) immunoassay analysis instrument designed for frequent testing, which requires a rapid and easy technique for changing chips. The key components of the mechanism are refractive index matching gel coated on the rear of the SPR chip and a float that presses the chip down. The refractive index matching gel made it possible to optically couple the chip and the prism of the SPR instrument easily via elastic deformation with no air bubbles. The float has an autonomous attitude control function that keeps the chip parallel in relation to the SPR instrument by employing the repulsive force of permanent magnets between the float and a float guide located in the SPR instrument. This function is realized by balancing the upward elastic force of the gel and the downward force of the float, which experiences a leveling force from the float guide. This system makes it possible to start an SPR measurement immediately after chip installation and to remove the chip immediately after the measurement with a simple and easy method that does not require any fine adjustment. Our sensor chip, which we installed using this mounting system, successfully performed an immunoassay measurement on a model antigen (spiked human-IgG) in a model real sample (non-homogenized milk) that included many kinds of interfering foreign substances without any sample pre-treatment. The ease of the chip installation/removal operation and simple measurement procedure are suitable for frequent on-site agricultural, environmental and medical testing. PMID:23202030

  9. Float-in powerhouses

    SciTech Connect

    Makela, G.A.

    1983-06-01

    The nation's inland waterway system affords a means of transporting large objects limited only by channel depth, size of locks and bridge clearances. The concept of prefabricating standardized, hydroelectric powerhouses at shipyards, transporting them along the inland waterways and installing them at navigation dams without powerhouses was examined for the McClellan-Kerr Arkansas River Navigation system. It was found that construction costs for the float-in design was very close to those of conventional sitebuilt design. Experience at Greenup Dam on the Ohio River where a float-in powerhouse has been installed indicated that construction time could be reduced if the float-in design was used. This time saving, use of standardized designs and construction of the float-in module at a shipyard may offer advantages that should be examined in more detailed when the power potential of the nation's low navigation dams is assessed.

  10. Floating production systems (FPS): Troll Oil and Kvaerner Concrete Semis

    SciTech Connect

    Loeset, O.

    1995-10-01

    This paper describes the main features of the Troll Oil concrete semi platform and the improvements and optimization carried further by the Kvaerner Concrete Semi. Significant elements contributing to marked cost reductions are pointed out, demonstrating the competitiveness of the concrete hull semi submersible platform.

  11. Development of novel gastroretentive floating particulate drug delivery system of gliclazide.

    PubMed

    Awasthi, Rajendra; Kulkarni, Giriraj T

    2012-09-01

    The objective of present project was to improve the dissolution profile of gliclazide by developing floating alginate beads using various biodegradable polymers like gelatin, pectin and hydroxypropylmethylcellulose (HPMC). The floating beads were prepared by a simple ionotropic gelatin method using calcium carbonate as gas generating agent. The developed beads were characterized by Fourier transform infrared spectroscopy analysis, differential scanning calorimetry, X-ray diffraction analysis and scanning electron microscopy (SEM). The prepared beads showed good in vitro floatation, which was dependent on the concentration of gas-forming agent. SEM photomicrographs confirmed that the developed beads were spherical in shape and had particle size in the range of 730 to 890 μm. The incorporation efficiency was found to be in the range of 59.96 to 85.1%. The cumulative percent drug release from the beads after 10 h dissolution study at pH 1.2 and pH 5.8 was in the range of 33 to 46% and 82 to 95% respectively. The concentration of the gas generating agent was found to influence the release rate. The mechanism of drug release was Fickian diffusion with swelling. The in vivo sub-acute hypoglycemic study in high fat diet induced diabetic C57BL/6J mice demonstrated significant (p < 0.05) hypoglycemic effect over a period of 12 h and 24 h, respectively, with HPMC and pectin beads. A significant (p & 0.05) reduction in fasting and non-fasting blood glucose levels, reduction in fasting plasma insulin level and a significant improvement in glucose tolerance were observed in animals treated with formulations. The developed beads were suitable carriers for improving the systemic absorption of gliclazide and maintaining reduced blood glucose levels. PMID:22920574

  12. Design and evaluation of polymeric coated minitablets as multiple unit gastroretentive floating drug delivery systems for furosemide.

    PubMed

    Meka, Lingam; Kesavan, Bhaskar; Kalamata, Venkatasimhadri Naidu; Eaga, Chandra Mohan; Bandari, Suresh; Vobalaboina, Venkateswarlu; Yamsani, Madhusudan Rao

    2009-06-01

    A gastro retentive floating drug delivery system with multiple-unit minitablets based on gas formation technique was developed for furosemide. The system consists of core units (solid dispersion of furosemide:povidone and other excipients), prepared by direct compression process, which are coated with two successive layers, one of which is an effervescent (sodium bicarbonate) layer and other one an outer polymeric layer of polymethacrylates. The formulations were evaluated for pharmacopoeial quality control tests and all the physical parameters evaluated were within the acceptable limits. Only the system using Eudragit RL30D and combination of them as polymeric layer could float within acceptable time. The time to float decreased as amount of the effervescent agent increased and, when the coating level of polymeric layer decreased. The drug release was controlled and linear with the square root of time. By increasing coating level of polymeric layer decreased the drug release. The rapid floating and the controlled release properties were achieved in this present study. The stability samples showed no significant change in dissolution profiles (f(2) = 81). The in vivo gastric residence time was examined by radiograms and it was observed that the units remained in the stomach for about 6 h. PMID:19009598

  13. Stools - floating

    MedlinePlus

    ... absorption of nutrients ( malabsorption ) or too much gas (flatulence). Considerations Most causes of floating stools are harmless. ... Bailey J. FPIN's Clinical Inquiries: Effective management of flatulence. Am Fam Physician Ohge H, Levitt MD. Intestinal ...

  14. Oceanic Rossby Waves Acting As a ``Hay Rake'' for Ecosystem Floating By-Products

    NASA Astrophysics Data System (ADS)

    Dandonneau, Yves; Vega, Andres; Loisel, Hubert; du Penhoat, Yves; Menkes, Christophe

    2003-11-01

    Recent satellite observations of Rossby waves and chlorophyll anomalies propagating in subtropical gyres have suggested that wave-induced upwelling could stimulate photosynthesis. Instead, we show that chlorophyll maxima are located in abnormally warm water, in Rossby wave-induced convergences. This excludes inputs of nutrients from deeper water. We argue that the sea color anomalies are not caused by chlorophyll but by floating particles evolved from the ecosystem and accumulated by Rossby waves, acting as ``marine hay rakes,'' in convergence zones. Such processes may be determinant for the distribution of living organisms in oligotrophic areas.

  15. Preparation and in vitro characterization of a non-effervescent floating drug delivery system for poorly soluble drug, glipizide.

    PubMed

    Meka, Venkata Srikanth; Pillai, Shreeni; Dharmalingham, Senthil Rajan; Sheshala, Ravi; Gorajana, Adinarayana

    2015-01-01

    The aim of the present study was to formulate a non-effervescent floating drug delivery system of glipizide, a poorly water soluble drug. The solubility of glipizide was initially enhanced using a solid dispersion (SD) strategy with the help of hydrophilic carriers such as poloxamer, cyclodextrin, and povidone. The optimized core material/SD was further formulated into non-effervescent floating tablets (NEFT) by using matrix ballooning inducers, such as crospovidone and release retarding agents including HPMC and PEO. Poloxamer-based solid dispersions prepared by a solvent evaporation technique showed the highest dissolution rate (1 : 10 drug to carrier ratio) compared with all other dispersions. NEFT were evaluated for all physico-chemical properties including in vitro buoyancy, dissolution, and release rate. All of the tablets were found to be within pharmacopoeial limits and all of the formulations exhibited good floating behavior. The formulations (F2 and F3) were optimized based on their 12 h drug retardation with continuous buoyancy. The optimized formulations were characterized using FTIR and DSC and no drug and excipient interaction was found. In-vitro buoyancy and dissolution studies showed that non-effervescent floating drug delivery systems provide a promising method of achieving prolonged gastric retention time and improved bioavailability of glipizide. PMID:25850215

  16. Nonlinear effects of unbalance in the rotor-floating ring bearing system of turbochargers

    NASA Astrophysics Data System (ADS)

    Tian, L.; Wang, W. J.; Peng, Z. J.

    2013-01-01

    Turbocharger (TC) rotor-floating ring bearing (FRB) system is characterised by high speed as well as high non-linearity. Using the run-up and run-down simulation method, this paper systematically investigates the influence of unbalance on the rotordynamic characteristics of a real TC-FRB system over the speed range from 0 Hz to 3500 Hz. The rotor is discretized by the finite element method, and the desired oil film forces at each simulation step are calculated by an efficient analytical method. The imposed unbalance amount and distribution are the variables considered in the performed non-stationary simulations. The newly obtained results evidently show the distinct phenomena brought about by the variations of the unbalance offset, which confirms that the unbalance level is a critical parameter for the system response. In the meantime, the variations of unbalance distribution, i.e. out-of-phase and in-phase unbalance, can lead to entirely different simulation results as well, which proves the distribution of unbalance is not negligible during the dynamic analysis of the rotor-FRB system. Additionally, considerable effort has been placed on the description as well as discussion of a unique phenomenon termed Critical Limit Cycle Oscillation (CLC Oscillation), which is of great importance and interest to the TC research and development.

  17. Inspection of float glass using a novel retroreflective laser scanning system

    NASA Astrophysics Data System (ADS)

    Holmes, Jonathan D.

    1997-07-01

    Since 1988, Image Automation has marketed a float glass inspection system using a novel retro-reflective laser scanning system. The (patented) instrument scans a laser beam by use of a polygon through the glass onto a retro-reflective screen, and collects the retro-reflected light off the polygon, such that a stationary image of the moving spot on the screen is produced. The spot image is then analyzed for optical effects introduced by defects within the glass, which typically distort and attenuate the scanned laser beam, by use of suitable detectors. The inspection system processing provides output of defect size, shape and severity, to the factory network for use in rejection or sorting of glass plates to the end customer. This paper briefly describes the principles of operation, the system architecture, and limitations to sensitivity and measurement repeatability. New instruments based on the retro-reflective scanning method have recently been developed. The principles and implementation are described. They include: (1) Simultaneous detection of defects within the glass and defects in a mirror coating on the glass surface using polarized light. (2) A novel distortion detector for very dark glass. (3) Measurement of optical quality (flatness/refractive homogeneity) of the glass using a position sensitive detector.

  18. Evaluation of kappa carrageenan as potential carrier for floating drug delivery system: Effect of pore forming agents.

    PubMed

    Selvakumaran, Suguna; Muhamad, Ida Idayu; Abd Razak, Saiful Izwan

    2016-01-01

    Floating hydrogels were prepared from kappa carrageenan containing CaCO3 and NaHCO3 as pore forming agents. The effects of CaCO3 and NaHCO3 on hydrogel characterizations were investigated and compared. Amoxicillin trihydrate was used as a model drug. Characterizations of the hydrogels were carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). As pore forming agents concentration increases, the porosity (%) and floating properties increased. NaHCO3 incorporated hydrogels showed higher porosity with shorter floating lag time (FLT) than CaCO3. Hydrogel which contained CaCO3 exhibited better gel stability over the control and NaHCO3 containing gel. Incorporation of CaCO3 into kappa carrageenan hydrogel showed smoother surface gels compared to those produced with NaHCO3. CaCO3 also showed higher drug entrapment efficiency and sustained drug release profile than NaHCO3. The results of these studies showed that, CaCO3 is an effective pore forming agents in κC hydrogels preparation as compare to NaHCO3. Thus, CaCO3 can be an excellent pore forming agent for an effective floating drug delivery system. PMID:26453870

  19. Laser-Heated Floating Zone Production of Single-Crystal Fibers

    NASA Technical Reports Server (NTRS)

    Ritzert, Frank; Westfall, Leonard

    1996-01-01

    This report describes how a laser-heated floating zone apparatus can be used to investigate single-crystal fibers of various compositions. A feedrod with a stoichiometric composition of high-purity powders was connected to a pedestal and fed into a laser scan where it combined with a single-crystal fiber seed. A molten zone was formed at this junction. As the feedrod was continuously fed into the laser scan, a single-crystal fiber of a prescribed orientation was withdrawn from the melt. The resultant fibers, whose diameters ranged from 100 to 250 gm, could then be evaluated on the basis of their growth behavior, physical properties, mechanical properties, and fiber perfection.

  20. Vertical viewing angle enhancement for the 360  degree integral-floating display using an anamorphic optic system.

    PubMed

    Erdenebat, Munkh-Uchral; Kwon, Ki-Chul; Yoo, Kwan-Hee; Baasantseren, Ganbat; Park, Jae-Hyeung; Kim, Eun-Soo; Kim, Nam

    2014-04-15

    We propose a 360 degree integral-floating display with an enhanced vertical viewing angle. The system projects two-dimensional elemental image arrays via a high-speed digital micromirror device projector and reconstructs them into 3D perspectives with a lens array. Double floating lenses relate initial 3D perspectives to the center of a vertically curved convex mirror. The anamorphic optic system tailors the initial 3D perspectives horizontally and vertically disperse light rays more widely. By the proposed method, the entire 3D image provides both monocular and binocular depth cues, a full-parallax demonstration with high-angular ray density and an enhanced vertical viewing angle. PMID:24978984

  1. Summary of Conclusions and Recommendations Drawn from the DeepCWind Scaled Floating Offshore Wind System Test Campaign: Preprint

    SciTech Connect

    Robertson, A. N.; Jonkman, J. M.; Masciola, M. D.; Molta, P.; Goupee, A. J.; Coulling, A. J.; Prowell, I.; Browning, J.

    2013-07-01

    The DeepCwind consortium is a group of universities, national labs, and companies funded under a research initiative by the U.S. Department of Energy (DOE) to support the research and development of floating offshore wind power. The two main objectives of the project are to better understand the complex dynamic behavior of floating offshore wind systems and to create experimental data for use in validating the tools used in modeling these systems. In support of these objectives, the DeepCwind consortium conducted a model test campaign in 2011 of three generic floating wind systems, a tension-leg platform (TLP), a spar-buoy (spar), and a semisubmersible (semi). Each of the three platforms was designed to support a 1/50th-scale model of a 5 MW wind turbine and was tested under a variety of wind/wave conditions. The focus of this paper is to summarize the work done by consortium members in analyzing the data obtained from the test campaign and its use for validating the offshore wind modeling tool, FAST.

  2. Design and evaluation of hydrophobic coated buoyant core as floating drug delivery system for sustained release of cisapride

    PubMed Central

    Jacob, Shery; Nair, Anroop B; Patil, Pandurang N

    2010-01-01

    An inert hydrophobic buoyant coated–core was developed as floating drug delivery system (FDDS) for sustained release of cisapride using direct compression technology. Core contained low density, porous ethyl cellulose, which was coated with an impermeable, insoluble hydrophobic coating polymer such as rosin. It was further seal coated with low viscosity hydroxypropyl methyl cellulose (HPMC E15) to minimize moisture permeation and better adhesion with an outer drug layer. It was found that stable buoyant core was sufficient to float the tablet more than 8 h without the aid of sodium bicarbonate and citric acid. Sustained release of cisapride was achieved with HPMC K4M in the outer drug layer. The floating lag time required for these novel FDDS was found to be zero, however it is likely that the porosity or density of the core is critical for floatability of these tablets. The in vitro release pattern of these tablets in simulated gastric fluid showed the constant and controlled release for prolonged time. It can be concluded that the hydrophobic coated buoyant core could be used as FDDS for gastroretentive delivery system of cisapride or other suitable drugs. PMID:24825997

  3. WindWaveFloat (WWF): Final Scientific Report

    SciTech Connect

    Alla Weinstein; Roddier, Dominique; Banister, Kevin

    2012-03-30

    Principle Power Inc. and National Renewable Energy Lab (NREL) have completed a contract to assess the technical and economic feasibility of integrating wave energy converters into the WindFloat, resulting in a new concept called the WindWaveFloat (WWF). The concentration of several devices on one platform could offer a potential for both economic and operational advantages. Wind and wave energy converters can share the electrical cable and power transfer equipment to transport the electricity to shore. Access to multiple generation devices could be simplified, resulting in cost saving at the operational level. Overall capital costs may also be reduced, provided that the design of the foundation can be adapted to multiple devices with minimum modifications. Finally, the WindWaveFloat confers the ability to increase energy production from individual floating support structures, potentially leading to a reduction in levelized energy costs, an increase in the overall capacity factor, and greater stability of the electrical power delivered to the grid. The research conducted under this grant investigated the integration of several wave energy device types into the WindFloat platform. Several of the resulting system designs demonstrated technical feasibility, but the size and design constraints of the wave energy converters (technical and economic) make the WindWaveFloat concept economically unfeasible at this time. Not enough additional generation could be produced to make the additional expense associated with wave energy conversion integration into the WindFloat worthwhile.

  4. Marine biological production from in situ oxygen measurements on a profiling float in the subarctic Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Bushinsky, Seth M.; Emerson, Steven

    2015-12-01

    Evaluating the organic carbon flux from the surface ocean to the interior (the marine biological pump) is essential for predictions of ocean carbon cycle feedback to climate change. One approach for determining these fluxes is to measure the concentration of oxygen in the upper ocean over a seasonal cycle, calculate the net O2 flux using an upper ocean model, and then use a stoichiometric relationship between oxygen evolved and organic carbon produced. Applying this tracer in a variety of ocean areas over seasonal cycles requires accurate O2 measurements on autonomous vehicles. Here we demonstrate this approach using an O2 sensor on a profiling float that is periodically calibrated against atmospheric pO2. Using accurate data and a model that includes all physical and biological processes influencing oxygen, we determine an annual net community production of 0.7 ± 0.5 mol C m-2 yr-1 in the northeast Pacific Ocean (50°N, 145°W) from June 2012 to June 2013. There is a strong seasonal cycle in net biological oxygen production with wintertime fluxes caused by bubble processes critical to determining the annual flux. Approximately 50% of net autotrophic production during summer months is consumed by net respiration during the winter. The result is a biological pump in the subarctic Pacific Ocean that is less than that determined by similar methods in the subtropics to the south. This estimate is significantly lower than that predicted by satellite remote sensing and global circulation models.

  5. Liuhua 11-1 development -- Subsea production system overview

    SciTech Connect

    Hall, J.E.; Sheng, W.Z.; Krenek, M.J.; Douglas, L.D.; Macfarlane, A.M.; Mohr, H.O.

    1996-12-31

    The Liuhua 11-1 Field is being developed using 20 subsea-completed wells. The development capitalizes on an innovative Modular Building Block method that does not require a seafloor template structure for the field`s diverless subsea production system. The modular assemblies are installed on the seafloor from semi-submersible floating production system while simultaneous in-field drilling and well completion activities are conducted. Electrical pumps downhole drive produced fluids through subsea pipelines to a floating production, storage, and offloading facility. The Liuhua 11-1 Development subsea system uses new and emerging diverless technology in several key areas. These include: a modular seafloor commingling production manifold system for multiple wells; wet-mateable electrical power connectors; horizontal spool trees and associated running tools; remotely operated vehicle (ROV) intervention packages; on-site-fabricated, rigid flowline and pipeline connections; and ROV-deployed, control-umbilical jumpers and instrument packages.

  6. Preparation of a matrix type multiple-unit gastro retentive floating drug delivery system for captopril based on gas formation technique: in vitro evaluation.

    PubMed

    Meka, Lingam; Kesavan, Bhaskar; Chinnala, Krishna Mohan; Vobalaboina, Venkateswarlu; Yamsani, Madhusudan Rao

    2008-01-01

    A gastro retentive floating drug delivery system with multiple-unit minitab's based on gas formation technique was developed in order to prolong the gastric residence time and to increase the overall bioavailability of the drug. The system consists of the drug-containing core units prepared by direct compression process, which are coated with three successive layers of an inner seal coat, effervescent layer (sodium bicarbonate) and an outer gas-entrapped polymeric membrane of an polymethacrylates (Eudragit RL30D, RS30D, and combinations of them). Only the system using Eudragit RL30D and combination of them as a gas-entrapped polymeric membrane could float. The time to float decreased as amount of the effervescent agent increased and coating level of gas-entrapped polymeric membrane decreased. The optimum system floated completely within 3 min and maintained the buoyancy over a period of 12 h. The drug release was controlled and linear with the square root of time. Increasing coating level of gas-entrapped polymeric membrane decreased the drug release. Both the rapid floating and the controlled release properties were achieved in the multiple-unit floating drug delivery system developed in this present study. The analysis of the parameter dissolution data after storage at 40 degrees C and 75% RH for 3 months showed, no significant change indicating the two dissolution profiles were considered to be similar (f2 value is more than 50). PMID:18459051

  7. Floating in situ gelling system for stomach site-specific delivery of clarithromycin to eradicate H. pylori.

    PubMed

    Rajinikanth, P S; Mishra, B

    2008-01-01

    Floating in situ gelling system of clarithromycin (FIGC) was prepared using gellan as gelling polymer and calcium carbonate as floating agent for potentially treating gastric ulcers, associated with Helicobacter pylori. Gellan based FIGC was prepared by dissolving varying concentrations of gellan in deionized water to which varying concentrations of drug and sucralfate were dispersed well. The formulation parameters like concentrations of gellan gum and sucralfate influenced the rate and extent of in vitro drug release significantly from FIGC. The addition of sucralfate to the formulation significantly suppressed the degradation of clarithromycin at low pH. The in vivo H. pylori clearance efficacy of prepared FIGC and clarithromycin suspension following oral administration, to H. pylori infected Mongolian gerbils was examined by polymerase chain reaction (PCR) technique and by a microbial culture method. FIGC showed a significant anti-H. pylori effect than that of clarithromycin suspension. The in situ gel formulation with sucralfate cleared H. pylori more effectively than that of formulation without sucralfate. In addition, the required amount of clarithromycin for eradication of H. pylori was found to be less from FIGC than from the corresponding clarithromycin suspension. It was concluded that prolonged gastrointestinal residence time and enhanced clarithromycin stability resulting from the floating in situ gel of clarithromycin might contribute better for complete clearance of H. pylori. PMID:18006101

  8. Innovative production system goes in off Ivory Coast

    SciTech Connect

    Childers, M.; Barnes, J. |

    1995-07-17

    The phased field development of the Lion and Panthere fields, offshore the Ivory Coast, includes a small floating production, storage, and offloading (FPSO) tanker with minimal processing capability as an early oil production system (EPS). For the long-term production scheme, the FPSO will be replaced by a converted jack up mobile offshore production system (MOPS) with full process equipment. The development also includes guyed-caisson well platforms, pipeline export for natural gas to fuel an onshore power plant, and a floating storage and offloading (FSO) tanker for oil export. Pipeline export for oil is a future possibility. This array of innovative strategies and techniques seldom has been brought together in a single project. The paper describes the development plan, early oil, jack up MOPS, and transport and installation.

  9. Floating modular drug delivery systems with buoyancy independent of release mechanisms to sustain amoxicillin and clarithromycin intra-gastric concentrations.

    PubMed

    Rossi, Alessandra; Conti, Chiara; Colombo, Gaia; Castrati, Luca; Scarpignato, Carmelo; Barata, Pedro; Sandri, Giuseppina; Caramella, Carla; Bettini, Ruggero; Buttini, Francesca; Colombo, Paolo

    2016-01-01

    Release modules of amoxicillin and clarithromycin combined in a single dosage form designed to float in the gastric content and to sustain the intra-gastric concentrations of these two antibiotics used for the eradication of Helicobacter pylori have been studied. The modules having a disc shape with curved bases were formulated as hydrophilic matrices. Two modules of clarithromycin were assembled by sticking the concave base of one module to the concave base of the other, creating an internal void chamber. The final dosage form was a floating assembly of three modules of clarithromycin and two of amoxicillin in which the drug release mechanism did not interfere with the floatation mechanism. The assembled system showed immediate in vitro floatation at pH 1.2, lasting 5 h. The in vitro antibiotics release profiles from individual modules and assembled systems exhibited linear release rate during buoyancy for at least 8 h. The predicted antibiotic concentrations in the stomach maintained for long time levels significantly higher than the respective minimum inhibitory concentrations (MIC). In addition, an in vivo absorption study performed on beagle dogs confirmed the slow release of clarithromycin and amoxicillin from the assembled system during the assembly's permanence in the stomach for at least 4 h. PMID:26065531

  10. Development of cloxacillin loaded multiple-unit alginate-based floating system by emulsion-gelation method.

    PubMed

    Malakar, Jadupati; Nayak, Amit Kumar; Pal, Dilipkumar

    2012-01-01

    This work investigates the development, optimization and in vitro evaluation of liquid paraffin-entrapped multiple-unit alginate-based floating system containing cloxacillin by emulsion-gelation method for gastro retentive delivery. The effect of process variables like drug to polymer ratio by weight, and liquid paraffin to water ratio by volume on various physicochemical properties in case of liquid paraffin-entrapped calcium alginate beads containing cloxacillin applicable to drug entrapment efficiency, density and drug release was optimized using 3(2) factorial design and analyzed using response surface methodology. The observed (actual values) responses were coincided well with the predicted values, given by the optimization technique. The optimized beads showed drug entrapment efficiency of 64.63±0.78%, density of 0.90±0.05 g/cm(3), and drug release of 56.72±0.85% in simulated gastric fluid (pH 1.2) after 8h with floating lag time of 8.45 min and floated well over 12h in simulated gastric fluid (pH 1.2). The average size of all dried beads ranged from 1.73±0.04 to 1.97±0.08 mm. The beads were characterized by SEM and FTIR for surface morphology and excipients-drug interaction analysis, respectively. All these beads showed prolonged sustained release of cloxacillin over 8h in simulated gastric fluid (pH 1.2). The cloxacillin release profile from liquid paraffin beads followed Korsmeyer-Peppas model over a period of 8h with anomalous (non-Fickian) diffusion mechanism for drug release. PMID:22020191

  11. Riser tensioning wave and tide compensating system for a floating platform

    SciTech Connect

    Heeres, C.J.; Larsen, C.H.

    1980-09-16

    A riser tensioner cylinder is provided with a hollow piston rod which forms a second cylinder in which a ram is reciprocated. The free end of the ram is connected to a link which in turn is connected to the end of the riser for providing tension on the riser. The ram reciprocates in the second cylinder under constant pressure to compensate for wave action on the floating platform and the second cylinder is automatically positioned within the first cylinder for adjustment for tide, vessel offset or other infrequent but variable factors.

  12. Development of novel floating delivery system based on psyllium: application on metformin hydrochloride.

    PubMed

    Rathnanand, Mahalaxmi; Narkhede, Rajkiran; Udupa, N; Kalra, Atin

    2013-06-01

    psyllium, a medicinally active gel forming natural polysaccharide and a dietary fiber has been used as a medicine in myriad of conditions such as constipation and inflammatory bowel syndrome. One of its more recent uses that have received attention has been its ability to reduce blood sugar levels in diabetics. Therefore present work is an attempt to formulate anti diabetic drug Metformin as a controlled release floating delivery making use of pysllium as release retardant and to assist the drug in stabilizing blood sugar level in type II diabetics. Drug and excipients compatibility studies were monitored by thermal analysis using differential scanning calorimeter (DSC) and Fourier transform infra red (FTIR). The DSC thermogram and FTIR of drug and drug-polymer mixture did not reveal any incompatibility. psyllium was tried in different concentrations along with other polymers like HPMC K15M and carbopol 940 to achieve the desired release profile. The total drug: polymer ratio was kept between 1:0.4 to 1:0.5, and different polymer combinations were tried to achieve desired drug release for 12 hours. The prepared tablets were evaluated for in vitro release studies and floating behavior. Our conclusion from the present study indicated that pysllium could potentially be used in conjunction with other polymers to formulate controlled release formulations of anti-diabetic drugs to provide better control over blood glucose levels. PMID:23410070

  13. Using a floating-gate MOS transistor as a transducer in a MEMS gas sensing system.

    PubMed

    Barranca, Mario Alfredo Reyes; Mendoza-Acevedo, Salvador; Flores-Nava, Luis M; Avila-García, Alejandro; Vazquez-Acosta, E N; Moreno-Cadenas, José Antonio; Casados-Cruz, Gaspar

    2010-01-01

    Floating-gate MOS transistors have been widely used in diverse analog and digital applications. One of these is as a charge sensitive device in sensors for pH measurement in solutions or using gates with metals like Pd or Pt for hydrogen sensing. Efforts are being made to monolithically integrate sensors together with controlling and signal processing electronics using standard technologies. This can be achieved with the demonstrated compatibility between available CMOS technology and MEMS technology. In this paper an in-depth analysis is done regarding the reliability of floating-gate MOS transistors when charge produced by a chemical reaction between metallic oxide thin films with either reducing or oxidizing gases is present. These chemical reactions need temperatures around 200 °C or higher to take place, so thermal insulation of the sensing area must be assured for appropriate operation of the electronics at room temperature. The operation principle of the proposal here presented is confirmed by connecting the gate of a conventional MOS transistor in series with a Fe(2)O(3) layer. It is shown that an electrochemical potential is present on the ferrite layer when reacting with propane. PMID:22163478

  14. Evaluation of kappa carrageenan as potential carrier for floating drug delivery system: Effect of cross linker.

    PubMed

    Selvakumaran, Suguna; Muhamad, Ida Idayu

    2015-12-30

    Genipin, a natural and non-toxic cross linker, was used to prepare cross linked floating kappa carrageenan/sodium carboxymethyl cellulose hydrogels and the effect of genipin on hydrogels characterization was investigated. Calcium carbonates were employed as gas forming agents. Ranitidine hydrochloride was used as drug. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were carried out to study the changes in the characteristics of hydrogels. Furthermore, scanning electron microscope (SEM) was performed to study microstructure of hydrogels. The result showed that all formulated hydrogels had excellent floating behavior. It was discovered that the cross linking reaction showed significant effect on gel strength, porosity and swelling ratio compared to non-cross linked hydrogels. It was found that the drug release was slower and lesser after being cross linked. Microstructure study shows that cross linked hydrogels exhibited hard and rough surface. Therefore, genipin can be an interesting cross linking agent for controlled drug delivery in gastrointestinal tract. PMID:26453788

  15. Floating-pulsatile release multiparticulate system for chronopharmacotherapy: effect of some hydrophobic additives on the buoyancy and release behavior of particles.

    PubMed

    Maghsoodi, M

    2014-01-01

    A blend of floating and pulsatile principles of a drug delivery system would have the advantage that a drug can be released in the upper gastrointestinal (GI) tract after a lag period, which is anticipated for chronotherapy. In this study, microballoons were prepared by an emulsion solvent diffusion technique using Eudragit S100, and hydrophobic additive (magnesium stearate, stearic acid or talc) for time- and site-specific drug release of piroxicam. The effect of hydrophobic additives on the production yield of floating microparticles, buoyant ability for 8 h, release of drug in simulated GI fluids (simulated gastric fluid [SGF] and simulated intestinal fluid [SIF]), mean particle size, apparent particle density, encapsulation efficiency of drug and physical state of incorporated drug were studied. Both production yield and buoyancy of the microballoons were affected by additives in the following order: magnesium stearate, stearic acid>free-additive>talc. The observed difference in yield and the buoyancy of the microballoons could be attributed to the hydrophobic character of the additives and the shell rigidity of the obtained microballoons. Incorporation of hydrophobic additives in the microballoons was found to impart the desired release properties to the microballoons by providing a 2-phase release pattern with initial slow release (5-6%) through 8 h in SGF followed by rapid pulse release (>92%) in SIF through 15 min. The microballoons co-formulated with magnesium stearate or stearic acid, combining excellent buoyancy and suitable drug release pattern of piroxicam, could be useful in chronopharmacotherapy in arthritis. PMID:23950100

  16. Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption

    NASA Astrophysics Data System (ADS)

    Troll, V. R.; Klügel, A.; Longpré, M.-A.; Burchardt, S.; Deegan, F. M.; Carracedo, J. C.; Wiesmaier, S.; Kueppers, U.; Dahren, B.; Blythe, L. S.; Hansteen, T. H.; Freda, C.; Budd, D. A.; Jolis, E. M.; Jonsson, E.; Meade, F. C.; Harris, C.; Berg, S. E.; Mancini, L.; Polacci, M.; Pedroza, K.

    2012-03-01

    A submarine eruption started off the south coast of El Hierro, Canary Islands, on 10 October 2011 and continues at the time of this writing (February 2012). In the first days of the event, peculiar eruption products were found floating on the sea surface, drifting for long distances from the eruption site. These specimens, which have in the meantime been termed "restingolites" (after the close-by village of La Restinga), appeared as black volcanic "bombs" that exhibit cores of white and porous pumice-like material. Since their brief appearance, the nature and origin of these "floating stones" has been vigorously debated among researchers, with important implications for the interpretation of the hazard potential of the ongoing eruption. The "restingolites" have been proposed to be either (i) juvenile high-silica magma (e.g. rhyolite), (ii) remelted magmatic material (trachyte), (iii) altered volcanic rock, or (iv) reheated hyaloclastites or zeolite from the submarine slopes of El Hierro. Here, we provide evidence that supports yet a different conclusion. We have analysed the textures and compositions of representative "restingolites" and compared the results to previous work on similar rocks found in the Canary Islands. Based on their high-silica content, the lack of igneous trace element signatures, the presence of remnant quartz crystals, jasper fragments and carbonate as well as wollastonite (derived from thermal overprint of carbonate) and their relatively high oxygen isotope values, we conclude that "restingolites" are in fact xenoliths from pre-island sedimentary layers that were picked up and heated by the ascending magma, causing them to partially melt and vesiculate. As they are closely resembling pumice in appearance, but are xenolithic in origin, we refer to these rocks as "xeno-pumice". The El Hierro xeno-pumices hence represent messengers from depth that help us to understand the interaction between ascending magma and crustal lithologies beneath the

  17. Floating Point Control Library

    Energy Science and Technology Software Center (ESTSC)

    2007-08-02

    Floating Point Control is a Library that allows for the manipulation of floating point unit exception masking funtions control exceptions in both the Streaming "Single Instruction, Multiple Data" Extension 2 (SSE2) unit and the floating point unit simultaneously. FPC also provides macros to set floating point rounding and precision control.

  18. A novel gastro-floating multiparticulate system for dipyridamole (DIP) based on a porous and low-density matrix core: in vitro and in vivo evaluation.

    PubMed

    Li, Zhao; Xu, Heming; Li, Shujuan; Li, Qijun; Zhang, Wenji; Ye, Tiantian; Yang, Xinggang; Pan, Weisan

    2014-01-30

    The study was aimed to develop a novel gastro-floating multiparticulate system based on a porous and low-density matrix core with excellent floatability. The gastro-floating pellets (GFP) were composed of a porous matrix core, a drug loaded layer (DIP and HPMC), a sub-coating layer (HPMC) and a retarding layer (Eudragit(®) NE 30D). The porous matrix cores were evaluated in specific. EC was chosen as the matrix membrane for its rigidity and minimal expansion to large extent. The porous matrix core was achieved by the complete release of the bulk water soluble excipient from the EC coated beads, and mannitol was selected as the optimal water soluble excipient. SEM photomicrographs confirmed the structure of porous matrix cores. The compositions of GFP were investigated and optimized by orthogonal array design. The optimized formulation could sustain the drug release for 12h and float on the dissolution medium for at least 12h without lag time to float. The pharmacokinetic study was conducted in beagle dogs, and the relative bioavailability of the test preparation was 193.11±3.43%. In conclusion, the novel gastro-floating pellets can be developed as a promising approach for the gastro-retentive drug delivery systems. PMID:24368104

  19. [Treatment effect of biological filtration and vegetable floating-bed combined system on greenhouse turtle breeding wastewater].

    PubMed

    Chen, Chong-Jun; Zhang, Rui; Xiang, Kun; Wu, Wei-Xiang

    2014-08-01

    Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China. PMID:25509094

  20. Freely floating smectic films.

    PubMed

    May, Kathrin; Harth, Kirsten; Trittel, Torsten; Stannarius, Ralf

    2014-05-19

    We have investigated the dynamics of freely floating smectic bubbles using high-speed optical imaging. Bubbles in the size range from a few hundred micrometers to several centimeters were prepared from collapsing catenoids. They represent ideal model systems for the study of thin-film fluid dynamics under well-controlled conditions. Owing to the internal smectic layer structure, the bubbles combine features of both soap films and vesicles in their unique shape dynamics. From a strongly elongated initial shape after pinch-off, they relax towards the spherical equilibrium, first by a slow redistribution of the smectic layers, and finally by weak, damped shape oscillations. In addition, we describe the rupture of freely floating smectic bubbles, and the formation and stability of smectic filaments. PMID:24692347

  1. Evaluation of the long-term sound reduction performance of resilient materials in floating floor systems

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Yoon; Kim, Jong-Mun; Kim, Jinyoung; Kim, Jeongho

    2016-03-01

    Building multi-dwelling units is one of the practical engineering solutions to housing shortage in urban areas with high population density. However, noise from upstairs is a major issue. The use of resilient materials in floating floor structures is recognized as an effective method to reduce such noise. In general, soft materials are considered as better resilient materials due to their superior performance in impact sound reduction. However, it is often overlooked that the sound reduction performance of soft resilient materials is susceptible to being degraded over time when subjected to a long-term load. In this study, the long-term performance of eight resilient materials is evaluated by monitoring their dynamic stiffness for 270 days under the two sustained load conditions: 250 N and 500 N. According to the experimental study, the dynamic stiffness increases consistently with loading time for all resilient materials. This leads to a decrease in the sound reduction performance. More rapid reduction in the dynamic stiffness and hence in the sound reduction performance is observed when a larger sustained load is applied. A greater decrease in the sound reduction performance is found in soft resilient materials.

  2. Development of a floating drug delivery system with superior buoyancy in gastric fluid using hot-melt extrusion coupled with pressurized CO₂.

    PubMed

    Almutairy, B K; Alshetaili, A S; Ashour, E A; Patil, H; Tiwari, R V; Alshehri, S M; Repka, M A

    2016-03-01

    The present study aimed to develop a continuous single-step manufacturing platform to prepare a porous, low-density, and floating multi-particulate system (mini-tablet, 4 mm size). This process involves injecting inert, non-toxic pressurized CO₂gas (P-CO₂) in zone 4 of a 16-mm hot-melt extruder (HME) to continuously generate pores throughout the carrier matrix. Unlike conventional methods for preparing floating drug delivery systems, additional chemical excipients and additives are not needed in this approach to create minute openings on the surface of the matrices. The buoyancy efficiency of the prepared floating system (injection of P-CO₂) in terms of lag time (0 s) significantly improved (P < 0.05), compared to the formulation prepared by adding the excipient sodium bicarbonate (lag time 120 s). The main advantages of this novel manufacturing technique include: (i) no additional chemical excipients need to be incorporated in the formulation, (ii) few manufacturing steps are required, (iii) high buoyancy efficiency is attained, and (iv) the extrudate is free of toxic solvent residues. Floating mini-tablets containing acetaminophen (APAP) as a model drug within the matrix-forming carrier (Eudragit® RL PO) have been successfully processed via this combined technique (P-CO₂/HME). Desired controlled release profile of APAP from the polymer Eudragit® RL PO is attained in the optimized formulation, which remains buoyant on the surface of gastric fluids prior to gastric emptying time (average each 4 h). PMID:27183706

  3. Flexible production systems

    NASA Astrophysics Data System (ADS)

    Chudakov, A. D.; Shchetinin, D. D.

    1986-03-01

    Flexible production systems are a technological tool design to automate multiple product line manufacturing. Flexible production systems provide an efficient means of organizing combined equipment operations and bring the production organization nearer to an unmanned arrangement or one requiring a limited number of workers. This is achieved by intensifying and automating manufacturing processes; coordinating the automated processes involved in warehousing and materials transport to maintain a tight production path; and using computers to automate production preparation and production control. The prerequisites for a change to these new production structures include numerical control NC tools and machining centers, power connection points for robots, automated conveying and warehousing systems controlled by microelectronic devices and control computer complexes consisting primarily of microprocessor-based units capable of controlling equipment via a direct connection and on a real-time basis. The types of flexible production systems in operation are divided into three groups: (1) flexible automated lines (GAL), (2) flexible production modules (GPM); and (3) flexible production complexes (GPK).

  4. Offshore Code Comparison Collaboration, Continuation: Phase II Results of a Floating Semisubmersible Wind System: Preprint

    SciTech Connect

    Robertson, A.; Jonkman, J.; Musial, W.; Vorpahl, F.; Popko, W.

    2013-11-01

    Offshore wind turbines are designed and analyzed using comprehensive simulation tools that account for the coupled dynamics of the wind inflow, aerodynamics, elasticity, and controls of the turbine, along with the incident waves, sea current, hydrodynamics, and foundation dynamics of the support structure. The Offshore Code Comparison Collaboration (OC3), which operated under the International Energy Agency (IEA) Wind Task 23, was established to verify the accuracy of these simulation tools [1]. This work was then extended under the Offshore Code Comparison Collaboration, Continuation (OC4) project under IEA Wind Task 30 [2]. Both of these projects sought to verify the accuracy of offshore wind turbine dynamics simulation tools (or codes) through code-to-code comparison of simulated responses of various offshore structures. This paper describes the latest findings from Phase II of the OC4 project, which involved the analysis of a 5-MW turbine supported by a floating semisubmersible. Twenty-two different organizations from 11 different countries submitted results using 24 different simulation tools. The variety of organizations contributing to the project brought together expertise from both the offshore structure and wind energy communities. Twenty-one different load cases were examined, encompassing varying levels of model complexity and a variety of metocean conditions. Differences in the results demonstrate the importance and accuracy of the various modeling approaches used. Significant findings include the importance of mooring dynamics to the mooring loads, the role nonlinear hydrodynamic terms play in calculating drift forces for the platform motions, and the difference between global (at the platform level) and local (at the member level) modeling of viscous drag. The results from this project will help guide development and improvement efforts for these tools to ensure that they are providing the accurate information needed to support the design and

  5. WindWaveFloat

    SciTech Connect

    Weinstein, Alla

    2011-11-01

    Presentation from the 2011 Water Peer Review includes in which principal investigator Alla Weinstein discusses project progress in development of a floating offshore wind structure - the WindFloat - and incorporation therin of a Spherical Wave Energy Device.

  6. Floating: sink or swim.

    PubMed

    Pronger, L

    1995-12-01

    Budget restrictions, fewer human resources and fluctuating patient populations have combined to increase the practice of floating general duty nurses. Floating occurs when a nurse from an overstaffed unit, based on patient load, is required to work in another unit that is understaffed. Floating is not a new practice, but it has always been an emotionally charged issue. Today, with more float pool nurses seeking the security of a permanent position in a home unit, the issue has increased in intensity. PMID:8713148

  7. The Design of Floats

    NASA Technical Reports Server (NTRS)

    Sottorf, W

    1938-01-01

    Following a summary of the multiplicity of domestic and foreign floats and a brief enumeration of the requirements of floats, the essential form parameters and their effect on the qualities of floats are detailed. On this basis a standard float design is developed which in model families with varying length/beam ratio and angle of dead rise is analyzed by an experimental method which permits its best utilization on any airplane.

  8. Study on a Mechanical Semi-Active Heave Compensation System of Drill String for Use on Floating Drilling Platform.

    PubMed

    Liu, Qingyou; Tang, Yang; Huang, Chongjun; Xie, Chong

    2015-01-01

    There are some disadvantages for existing heave compensation systems of drill string used for the Floating Drilling Platform (FDP), including high energy consumption, large and complex structure, and expensive manufacturing and maintenance costs. In view of the above, we present a streamlined mechanical semi-active heave compensation system (MSAHC) in this study. This system consists of active compensation part with the pinion and rack and passive compensation part. In order to evaluate system performance of the MSAHC, we establish its simulation model with AMEsim software. In the process of simulation, displacement of rotary hook and energy consumption is regarded as performance parameters of the system. And the change rule of two performance parameters are analyzed by changing these design parameters including gear radius of the pinion and rack, scale coefficient of PID, rotary hook load, heave height and heave period of the FDP, and accumulator volume. Then, based on the simulation results of the MSAHC system performance, we have selected out a best set of design parameters from them. Moreover, the feasibility of the design scheme of the MSAHC is effectively verified by comparison with the existing three heave compensation system. The result shows that the energy consumption of the MSAHC is lower than the active heave compensation system (AHC) and the semi-active heave compensation system (SAHC) when achieving a same compensation effect as well as the accumulator volume of MSAHC is half of the passive heave compensation system (PHC). Therefore, the new designed MSAHC not only ensure compensation effect but also lower energy consumption, and its structure is simplified by adopting the simple mechanical structure to decrease manufacturing cost, maintenance cost and floor space. PMID:26186620

  9. Study on a Mechanical Semi-Active Heave Compensation System of Drill String for Use on Floating Drilling Platform

    PubMed Central

    Liu, Qingyou; Tang, Yang; Huang, Chongjun; Xie, Chong

    2015-01-01

    There are some disadvantages for existing heave compensation systems of drill string used for the Floating Drilling Platform (FDP), including high energy consumption, large and complex structure, and expensive manufacturing and maintenance costs. In view of the above, we present a streamlined mechanical semi-active heave compensation system (MSAHC) in this study. This system consists of active compensation part with the pinion and rack and passive compensation part. In order to evaluate system performance of the MSAHC, we establish its simulation model with AMEsim software. In the process of simulation, displacement of rotary hook and energy consumption is regarded as performance parameters of the system. And the change rule of two performance parameters are analyzed by changing these design parameters including gear radius of the pinion and rack, scale coefficient of PID, rotary hook load, heave height and heave period of the FDP, and accumulator volume. Then, based on the simulation results of the MSAHC system performance, we have selected out a best set of design parameters from them. Moreover, the feasibility of the design scheme of the MSAHC is effectively verified by comparison with the existing three heave compensation system. The result shows that the energy consumption of the MSAHC is lower than the active heave compensation system (AHC) and the semi-active heave compensation system (SAHC) when achieving a same compensation effect as well as the accumulator volume of MSAHC is half of the passive heave compensation system (PHC). Therefore, the new designed MSAHC not only ensure compensation effect but also lower energy consumption, and its structure is simplified by adopting the simple mechanical structure to decrease manufacturing cost, maintenance cost and floor space. PMID:26186620

  10. An experimental study of the effect of mooring systems on the dynamics of a SPAR buoy-type floating offshore wind turbine

    NASA Astrophysics Data System (ADS)

    Hong, Sinpyo; Lee, Inwon; Park, Seong Hyeon; Lee, Cheolmin; Chun, Ho-Hwan; Lim, Hee Chang

    2015-05-01

    An experimental study of the effect of mooring systems on the dynamics of a SPAR buoy-type floating offshore wind turbine is presented. The effects of the Center of Gravity (COG), mooring line spring constant, and fair-lead location on the turbine's motion in response to regular waves are investigated. Experimental results show that for a typical mooring system of a SPAR buoy-type Floating Offshore Wind Turbine (FOWT), the effect of mooring systems on the dynamics of the turbine can be considered negligible. However, the pitch decreases notably as the COG increases. The COG and spring constant of the mooring line have a negligible effect on the fairlead displacement. Numerical simulation and sensitivity analysis show that the wind turbine motion and its sensitivity to changes in the mooring system and COG are very large near resonant frequencies. The test results can be used to validate numerical simulation tools for FOWTs.

  11. An experimental study of the effect of mooring systems on the dynamics of a SPAR buoy-type floating offshore wind turbine

    NASA Astrophysics Data System (ADS)

    Hong, Sinpyo; Lee, Inwon; Park, Seong Hyeon; Lee, Cheolmin; Chun, Ho-Hwan; Lim, Hee Chang

    2015-09-01

    An experimental study of the effect of mooring systems on the dynamics of a SPAR buoy-type floating offshore wind turbine is presented. The effects of the Center of Gravity (COG), mooring line spring constant, and fair-lead location on the turbine's motion in response to regular waves are investigated. Experimental results show that for a typical mooring system of a SPAR buoy-type Floating Offshore Wind Turbine (FOWT), the effect of mooring systems on the dynamics of the turbine can be considered negligible. However, the pitch decreases notably as the COG increases. The COG and spring constant of the mooring line have a negligible effect on the fairlead displacement. Numerical simulation and sensitivity analysis show that the wind turbine motion and its sensitivity to changes in the mooring system and COG are very large near resonant frequencies. The test results can be used to validate numerical simulation tools for FOWTs.

  12. Swelling/floating capability and drug release characterizations of gastroretentive drug delivery system based on a combination of hydroxyethyl cellulose and sodium carboxymethyl cellulose.

    PubMed

    Chen, Ying-Chen; Ho, Hsiu-O; Liu, Der-Zen; Siow, Wen-Shian; Sheu, Ming-Thau

    2015-01-01

    The aim of this study was to characterize the swelling and floating behaviors of gastroretentive drug delivery system (GRDDS) composed of hydroxyethyl cellulose (HEC) and sodium carboxymethyl cellulose (NaCMC) and to optimize HEC/NaCMC GRDDS to incorporate three model drugs with different solubilities (metformin, ciprofloxacin, and esomeprazole). Various ratios of NaCMC to HEC were formulated, and their swelling and floating behaviors were characterized. Influences of media containing various NaCl concentrations on the swelling and floating behaviors and drug solubility were also characterized. Finally, release profiles of the three model drugs from GRDDS formulation (F1-4) and formulation (F1-1) were examined. Results demonstrated when the GRDDS tablets were tested in simulated gastric solution, the degree of swelling at 6 h was decreased for each formulation that contained NaCMC in comparison to those in de-ionized water (DIW). Of note, floating duration was enhanced when in simulated gastric solution compared to DIW. Further, the hydration of tablets was found to be retarded as the NaCl concentration in the medium increased resulting in smaller gel layers and swelling sizes. Dissolution profiles of the three model drugs in media containing various concentrations of NaCl showed that the addition of NaCl to the media affected the solubility of the drugs, and also their gelling behaviors, resulting in different mechanisms for controlling a drug's release. The release mechanism of the freely water-soluble drug, metformin, was mainly diffusion-controlled, while those of the water-soluble drug, ciprofloxacin, and the slightly water-soluble drug, esomeprazole, were mainly anomalous diffusion. Overall results showed that the developed GRDDS composed of HEC 250HHX and NaCMC of 450 cps possessed proper swelling extents and desired floating periods with sustained-release characteristics. PMID:25617891

  13. Swelling/Floating Capability and Drug Release Characterizations of Gastroretentive Drug Delivery System Based on a Combination of Hydroxyethyl Cellulose and Sodium Carboxymethyl Cellulose

    PubMed Central

    Chen, Ying-Chen; Ho, Hsiu-O; Liu, Der-Zen; Siow, Wen-Shian; Sheu, Ming-Thau

    2015-01-01

    The aim of this study was to characterize the swelling and floating behaviors of gastroretentive drug delivery system (GRDDS) composed of hydroxyethyl cellulose (HEC) and sodium carboxymethyl cellulose (NaCMC) and to optimize HEC/NaCMC GRDDS to incorporate three model drugs with different solubilities (metformin, ciprofloxacin, and esomeprazole). Various ratios of NaCMC to HEC were formulated, and their swelling and floating behaviors were characterized. Influences of media containing various NaCl concentrations on the swelling and floating behaviors and drug solubility were also characterized. Finally, release profiles of the three model drugs from GRDDS formulation (F1-4) and formulation (F1-1) were examined. Results demonstrated when the GRDDS tablets were tested in simulated gastric solution, the degree of swelling at 6 h was decreased for each formulation that contained NaCMC in comparison to those in de-ionized water (DIW). Of note, floating duration was enhanced when in simulated gastric solution compared to DIW. Further, the hydration of tablets was found to be retarded as the NaCl concentration in the medium increased resulting in smaller gel layers and swelling sizes. Dissolution profiles of the three model drugs in media containing various concentrations of NaCl showed that the addition of NaCl to the media affected the solubility of the drugs, and also their gelling behaviors, resulting in different mechanisms for controlling a drug’s release. The release mechanism of the freely water-soluble drug, metformin, was mainly diffusion-controlled, while those of the water-soluble drug, ciprofloxacin, and the slightly water-soluble drug, esomeprazole, were mainly anomalous diffusion. Overall results showed that the developed GRDDS composed of HEC 250HHX and NaCMC of 450 cps possessed proper swelling extents and desired floating periods with sustained-release characteristics. PMID:25617891

  14. Belle II production system

    NASA Astrophysics Data System (ADS)

    Miyake, Hideki; Grzymkowski, Rafal; Ludacka, Radek; Schram, Malachi

    2015-12-01

    The Belle II experiment will record a similar quantity of data to LHC experiments and will acquire it at similar rates. This requires considerable computing, storage and network resources to handle not only data created by the experiment but also considerable amounts of simulated data. Consequently Belle II employs a distributed computing system to provide the resources coordinated by the the DIRAC interware. DIRAC is a general software framework that provides a unified interface among heterogeneous computing resources. In addition to the well proven DIRAC software stack, Belle II is developing its own extension called BelleDIRAC. BelleDIRAC provides a transparent user experience for the Belle II analysis framework (basf2) on various environments and gives access to file information managed by LFC and AMGA metadata catalog. By unifying DIRAC and BelleDIRAC functionalities, Belle II plans to operate an automated mass data processing framework named a “production system”. The Belle II production system enables large-scale raw data transfer from experimental site to raw data centers, followed by massive data processing, and smart data delivery to each remote site. The production system is also utilized for simulated data production and data analysis. Although development of the production system is still on-going, recently Belle II has prepared prototype version and evaluated it with a large scale simulated data production. In this presentation we will report the evaluation of the prototype system and future development plans.

  15. A productivity measurement system

    SciTech Connect

    Sweet, R.H.; Blain, D.A.

    1988-01-01

    The system for measuring productivity of the EG and G Idaho, Inc., Drafting Group was developed at the Idaho National Engineering Laboratory. The Productivity Measurement System, built on relational data base management software, provides up-to-date information on the productivity of the Drafting Group, the drafting units, and the individual Drafters. The system was developed using data collected in the Drafters Time and Activities Log and Task Baseline Agreement (TBA) that was input to the data base. Using these data, an average usage rate in hours per square foot of drawing, CAD and Manual, was established. This provided a benchmark for management reports that are depicted graphically for ease of trend analyses. In addition, the system provides each drafter an indicator as to where they stand in relation to their peers, and all of the information provided leads to more accurate drafting estimates. 11 figs.

  16. Comparison of Alcian Blue, Trypan Blue, and Toluidine Blue for Visualization of the Primo Vascular System Floating in Lymph Ducts

    PubMed Central

    Kim, Da-Un; Han, Jae Won; Jung, Sharon Jiyoon; Lee, Seung Hwan; Cha, Richard; Chang, Byung-Soo; Soh, Kwang-Sup

    2015-01-01

    The primo vascular system (PVS), floating in lymph ducts, was too transparent to be observed by using a stereomicroscope. It was only detectable with the aid of staining dyes, for instance, Alcian blue, which was injected into the lymph nodes. Some dyes were absorbed preferentially by the PVS than the lymph wall. It remains a standing problem to know what dyes are absorbed better by the PVS than the lymph walls. Such information would be useful to unravel the biochemical properties of the PVS that are badly in need for obtaining large amount of PVS specimens. In the current work we tried two other familiar dyes which were used in PVS research before. We found that Trypan blue and toluidine blue did not visualize the PVS. Trypan blue was cleared by the natural washing. Toluidine blue did not stain the PVS, but it did leave stained spots in the lymph wall and its surrounding tissues, and it leaked out of the lymph wall to stain surrounding connective tissues. These completely different behaviors of the three dyes were found for the first time in the current work and provide valuable information to elucidate the mechanism through which some special dyes stained the PVS preferentially compared to the lymphatic wall. PMID:26379749

  17. Potential Formation in a Bounded Two-Electron Temperature Plasma System with Floating Collector That Emits Electrons

    NASA Astrophysics Data System (ADS)

    Gyergyek, Tomaž; Čerček, Milan

    2004-04-01

    Formation of the plasma potential in a plasma that contains energetic electrons and is bounded by a floating collector that emits electrons is studied theoretically. The problem is treated by a static. kinetic plasma-sheath model of Schwager and Birdsall [Phys. Fluids B 2 (1990) 1057], which we have extended in order to include additional energetic electron population. The distribution of these electrons is assumed to be a high-temperature Maxwellian. They are called hot electrons. In the paper we study effects of the density and temperature of the hot electrons on the formation of the plasma potential. The model shows that for certain densities and temperatures of the hot electron population plasmas with two different plasma potentials can coexist in the system. These two plasmas are separated spatially by a double layer. For the case when there is no emission of electrons from the collector, results of the model are compared with computer simulation and very good agreement between the model and the simulation is found. The simulation also confirms existence of two plasmas with two different potentials separated by a double layer.

  18. Shell chooses floating units for central N. Sea projects

    SciTech Connect

    Weener, R.

    1996-08-19

    As new fields awaiting development tend to become smaller, as oil prices remain flat, and as reserves are exploited in ever more-remote and deep waters, so interest in floating production systems is growing. The Shell Group has long experience of floating production, storage, and offtake (FPSO) facilities, subsea development equipment, and other related technologies such as flexible risers. The first Shell FPSO was installed in Castellon field in the Mediterranean Sea in 1977. Since then FPSO systems have been installed in many areas of the world and have evolved as safe and environmentally sound installations which can confidently be employed in ever more-demanding areas. The paper describes FPSO evaluation, North Sea status, FPSOs in Shell Exploration and Production, Curlew field plans, further developments, FPSO market, and future trends.

  19. Design and evaluation of gastroretentive levofloxacin floating mini-tablets-in-capsule system for eradication of Helicobacter pylori.

    PubMed

    El-Zahaby, Sally A; Kassem, Abeer A; El-Kamel, Amal H

    2014-12-01

    Gastroretentive levofloxacin (LVF) floating mini-tablets for the eradication of Helicobacter pylori (H. pylori) were prepared using the matrix forming polymer hydroxypropyl methylcellulose (HPMC K100M), alone or with Carbopol 940P in different ratios by wet granulation technique. Buoyancy of mini-tablets was achieved by an addition of an effervescent mixture consisting of sodium bicarbonate and anhydrous citric acid to some formulations. The prepared mini-tablets were evaluated for weight variation, thickness, friability, hardness, drug content, in vitro buoyancy, water uptake and in vitro release. The optimized formula was subjected to further studies: FT-IR, DSC analysis and in vivo examination in healthy volunteers. The prepared mini-tablets exhibited satisfactory physicochemical characteristics. Incorporation of gas-generating agent improved the floating parameters. HPMC K100M mini-tablet formulation (F1) offered the best controlled drug release (>8 h) along with floating lag time <1 s and total floating time >24 h. The obtained DSC thermograms and FT-IR charts indicated that there is no positive evidence for the interaction between LVF and ingredients of the optimized formula. The in vivo test confirmed the success of the optimized formula F1 in being retained in the stomach of the volunteers for more than 4 h. LVF floating mini-tablets based on HPMC K100M is a promising formulation for eradication of H. pylori. PMID:25561871

  20. Design and evaluation of gastroretentive levofloxacin floating mini-tablets-in-capsule system for eradication of Helicobacter pylori

    PubMed Central

    El-Zahaby, Sally A.; Kassem, Abeer A.; El-Kamel, Amal H.

    2014-01-01

    Gastroretentive levofloxacin (LVF) floating mini-tablets for the eradication of Helicobacter pylori (H. pylori) were prepared using the matrix forming polymer hydroxypropyl methylcellulose (HPMC K100M), alone or with Carbopol 940P in different ratios by wet granulation technique. Buoyancy of mini-tablets was achieved by an addition of an effervescent mixture consisting of sodium bicarbonate and anhydrous citric acid to some formulations. The prepared mini-tablets were evaluated for weight variation, thickness, friability, hardness, drug content, in vitro buoyancy, water uptake and in vitro release. The optimized formula was subjected to further studies: FT-IR, DSC analysis and in vivo examination in healthy volunteers. The prepared mini-tablets exhibited satisfactory physicochemical characteristics. Incorporation of gas-generating agent improved the floating parameters. HPMC K100M mini-tablet formulation (F1) offered the best controlled drug release (>8 h) along with floating lag time <1 s and total floating time >24 h. The obtained DSC thermograms and FT-IR charts indicated that there is no positive evidence for the interaction between LVF and ingredients of the optimized formula. The in vivo test confirmed the success of the optimized formula F1 in being retained in the stomach of the volunteers for more than 4 h. LVF floating mini-tablets based on HPMC K100M is a promising formulation for eradication of H. pylori. PMID:25561871

  1. Floating plant dominance as a stable state

    PubMed Central

    Scheffer, Marten; Szabó, Sándor; Gragnani, Alessandra; van Nes, Egbert H.; Rinaldi, Sergio; Kautsky, Nils; Norberg, Jon; Roijackers, Rudi M. M.; Franken, Rob J. M.

    2003-01-01

    Invasion by mats of free-floating plants is among the most important threats to the functioning and biodiversity of freshwater ecosystems ranging from temperate ponds and ditches to tropical lakes. Dark, anoxic conditions under thick floating-plant cover leave little opportunity for animal or plant life, and they can have large negative impacts on fisheries and navigation in tropical lakes. Here, we demonstrate that floating-plant dominance can be a self-stabilizing ecosystem state, which may explain its notorious persistence in many situations. Our results, based on experiments, field data, and models, represent evidence for alternative domains of attraction in ecosystems. An implication of our findings is that nutrient enrichment reduces the resilience of freshwater systems against a shift to floating-plant dominance. On the other hand, our results also suggest that a single drastic harvest of floating plants can induce a permanent shift to an alternative state dominated by rooted, submerged growth forms. PMID:12634429

  2. Characterizations of plasticized polymeric film coatings for preparing multiple-unit floating drug delivery systems (muFDDSs) with controlled-release characteristics.

    PubMed

    Hung, Sheng-Feng; Hsieh, Chien-Ming; Chen, Ying-Chen; Wang, Yu-Chun; Ho, Hsiu-O; Sheu, Ming-Thau

    2014-01-01

    Effervescent multiple-unit floating drug delivery systems (muFDDSs) consisting of drug (lorsartan)- and effervescent (sodium bicarbonate)-containing pellets were characterized in this study. The mechanical properties (stress and strain at rupture, Young's modulus, and toughness) of these plasticized polymeric films of acrylic (Eudragit RS, RL, and NE) and cellulosic materials (ethyl cellulose (EC), and Surelease) were examined by a dynamic mechanical analyzer. Results demonstrated that polymeric films prepared from Surelease and EC were brittle with less elongation compared to acrylic films. Eudragit NE films were very flexible in both the dry and wet states. Because plasticizer leached from polymeric films during exposure to the aqueous medium, plasticization of wet Eudragit RS and RL films with 15% triethyl citrate (TEC) or diethyl phthalate (DEP) resulted in less elongation. DEP might be the plasticizer of choice among the plasticizers examined in this study for Eudragit RL to provide muFDDSs with a short time for all pellets to float (TPF) and a longer period of floating. Eudragit RL and RS at a 1∶1 ratio plasticized with 15% DEP were optimally selected as the coating membrane for the floating system. Although the release of losartan from the pellets was still too fast as a result of losartan being freely soluble in water, muFDDSs coated with Eudragit RL and RS at a 1∶1 ratio might have potential use for the sustained release of water-insoluble or the un-ionized form of drugs from gastroretentive drug delivery systems. PMID:24967594

  3. Characterizations of Plasticized Polymeric Film Coatings for Preparing Multiple-Unit Floating Drug Delivery Systems (muFDDSs) with Controlled-Release Characteristics

    PubMed Central

    Chen, Ying-Chen; Wang, Yu-Chun; Ho, Hsiu-O; Sheu, Ming-Thau

    2014-01-01

    Effervescent multiple-unit floating drug delivery systems (muFDDSs) consisting of drug (lorsartan)- and effervescent (sodium bicarbonate)-containing pellets were characterized in this study. The mechanical properties (stress and strain at rupture, Young’s modulus, and toughness) of these plasticized polymeric films of acrylic (Eudragit RS, RL, and NE) and cellulosic materials (ethyl cellulose (EC), and Surelease) were examined by a dynamic mechanical analyzer. Results demonstrated that polymeric films prepared from Surelease and EC were brittle with less elongation compared to acrylic films. Eudragit NE films were very flexible in both the dry and wet states. Because plasticizer leached from polymeric films during exposure to the aqueous medium, plasticization of wet Eudragit RS and RL films with 15% triethyl citrate (TEC) or diethyl phthalate (DEP) resulted in less elongation. DEP might be the plasticizer of choice among the plasticizers examined in this study for Eudragit RL to provide muFDDSs with a short time for all pellets to float (TPF) and a longer period of floating. Eudragit RL and RS at a 1∶1 ratio plasticized with 15% DEP were optimally selected as the coating membrane for the floating system. Although the release of losartan from the pellets was still too fast as a result of losartan being freely soluble in water, muFDDSs coated with Eudragit RL and RS at a 1∶1 ratio might have potential use for the sustained release of water-insoluble or the un-ionized form of drugs from gastroretentive drug delivery systems. PMID:24967594

  4. Floating Silicon Method

    SciTech Connect

    Kellerman, Peter

    2013-12-21

    The Floating Silicon Method (FSM) project at Applied Materials (formerly Varian Semiconductor Equipment Associates), has been funded, in part, by the DOE under a “Photovoltaic Supply Chain and Cross Cutting Technologies” grant (number DE-EE0000595) for the past four years. The original intent of the project was to develop the FSM process from concept to a commercially viable tool. This new manufacturing equipment would support the photovoltaic industry in following ways: eliminate kerf losses and the consumable costs associated with wafer sawing, allow optimal photovoltaic efficiency by producing high-quality silicon sheets, reduce the cost of assembling photovoltaic modules by creating large-area silicon cells which are free of micro-cracks, and would be a drop-in replacement in existing high efficiency cell production process thereby allowing rapid fan-out into the industry.

  5. Production Systems. Laboratory Activities.

    ERIC Educational Resources Information Center

    Gallaway, Ann, Ed.

    This production systems guide provides teachers with learning activities for secondary students. Introductory materials include an instructional planning outline and worksheet, an outline of essential elements, domains and objectives, a course description, and a content outline. The guide contains 30 modules on the following topics: production…

  6. Innovating blackberry production system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article provides an overview of progress made on the blackberry production system at the Appalachian Fruit Research Station in Kearneysville, WV. Several lines of research have made a significant positive impact to the blackberry industry as the new technology has have been successfully transf...

  7. Organic watermelon production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The increasing perception by consumers that organic food tastes better and is healthier continues to expand the demand for organically produced crops. Research investigating certified organic production requires a systems approach to determine the optimum combination of individual components to max...

  8. Characterization of Chironomidae (Diptera) surface-floating pupal exuviae sample sort time from coastal tropical aquatic systems.

    PubMed

    Kranzfelder, Petra; Ferrington, Leonard C

    2015-03-01

    Many studies either ignore chironomids or only identify specimens to subfamily or tribe due to the associated difficulty and high cost with processing and identifying larvae. An efficient form of sampling chironomids involves collections of surface-floating pupal exuviae (SFPE). SFPE sample sorting has been shown to be more time efficient than traditional dip-net methods in temperate urban and peri-urban streams. However, no published studies have tested the time efficiency of SFPE sample sorting from coastal tropical aquatic systems. We calculated sort times for SFPE samples collected from a coastal tropical stream and an estuary and used multiple linear regression analysis to quantify the relationship between sample sort time and number of specimens, average body length of specimens, and dry weight of sample residue. The average amount of time required to sort very small samples was 69.3 min, while moderate samples averaged 85.6 min and large samples averaged 153.5 min. However, on average, small samples were nine times more time consuming per specimen than large samples. Additionally, dry weight of small-sized residue and the number of specimens contributed significantly to sort time. Therefore, we recommend collecting larger samples, which can be achieved by sampling for 20 min over 200-m reaches for stream sites and 500- to 1,000-m reaches for riverine and estuarine sites. Also, we suggest collecting during periods of low wave action and disturbance by boat wake to reduce the amount of sample residue. This research will enhance project planning and budgeting of future studies using the SFPE method to monitor coastal tropical aquatic systems. PMID:25647801

  9. Grating exchange system of independent mirror supported by floating rotary stage

    NASA Astrophysics Data System (ADS)

    Zhang, Jianhuan; Tao, Jin; Liu, Yan; Nan, Yan

    2015-10-01

    The performance of The Grating Exchange System can satisfy the Thirty Meter Telescope - TMT for astronomical observation WFOS index requirements and satisfy the requirement of accuracy in the grating exchange. It is used to install in the MOBIE and a key device of MOBIE. The Wide Field Optical Spectrograph (WFOS) is one of the three first-light observing capabilities selected by the TMT Science Advisory Committee. The Multi-Object Broadband Imaging Echellette (MOBIE) instrument design concept has been developed to address the WFOS requirements as described in the TMT Science-Based Requirements Document (SRD). The Grating Exchange System uses a new type of separate movement way of three grating devices and a mirror device. Three grating devices with a mirror are able to achieve independence movement. This kind of grating exchange system can effectively solve the problem that the volume of the grating change system is too large and that the installed space of MOBIE instruments is too limit. This system adopts the good stability, high precision of rotary stage - a kind of using air bearing (Air bearing is famous for its ultra-high precision, and can meet the optical accuracy requirement) and rotation positioning feedback gauge turntable to support grating device. And with a kind of device which can carry greater weight bracket fixed on the MOBIE instrument, with two sets of servo motor control rotary stage and the mirror device respectively. And we use the control program to realize the need of exercising of the grating device and the mirror device. Using the stress strain analysis software--SolidWorks for stress and strain analysis of this structure. And then checking the structure of the rationality and feasibility. And prove that this system can realize the positioning precision under different working conditions can meet the requirements of imaging optical grating diffraction efficiency and error by the calculation and optical performance analysis.

  10. Raft and floating radio frequency identification (RFID) antenna systems for detecting and estimating abundance of PIT-tagged fish in rivers

    USGS Publications Warehouse

    Fetherman, Eric R.; Avila, Brian W.; Winkelman, Dana L.

    2016-01-01

    Portable radio frequency identification (RFID) PIT tag antenna systems are increasingly being used in studies examining aquatic animal movement, survival, and habitat use, and their design flexibility permits application in a wide variety of settings. We describe the construction, use, and performance of two portable floating RFID PIT tag antenna systems designed to detect fish that were unavailable for recapture using stationary antennas or electrofishing. A raft antenna system was designed to detect and locate PIT-tagged fish in relatively long (i.e., ≥10 km) river reaches, and consisted of two antennas: (1) a horizontal antenna (4 × 1.2 m) installed on the bottom of the raft and used to detect fish in shallower river reaches (<1 m), and (2) a vertical antenna (2.7 × 1.2 m) for detecting fish in deeper pools (≥1 m). Detection distances of the horizontal antenna were between 0.7 and 1.0 m, and detection probability was 0.32 ± 0.02 (mean ± SE) in a field test using rocks marked with 32-mm PIT tags. Detection probability of PIT-tagged fish in the Cache la Poudre River, Colorado, using the raft antenna system, which covered 21% of the wetted area, was 0.14 ± 0.14. A shore-deployed floating antenna (14.6 × 0.6 m), which covered 100% of the wetted area, was designed for use by two operators for detecting and locating PIT-tagged fish in shorter (i.e., <2 km) river reaches. Detection distances of the shore-deployed floating antenna were between 0.7 and 0.8 m, and detection probabilities during field deployment in the St. Vrain River exceeded 0.52. The shore-deployed floating antenna was also used to estimate abundance of PIT-tagged fish. Results suggest that the shore-deployed floating antenna could be used as an alternative to estimating abundance using traditional sampling methods such as electrofishing.

  11. Target berthing and base reorientation of free-floating space robotic system after capturing

    NASA Astrophysics Data System (ADS)

    Xu, Wenfu; Li, Cheng; Liang, Bin; Xu, Yangsheng; Liu, Yu; Qiang, Wenyi

    2009-01-01

    Space robots are playing an increasingly important role in on-orbital servicing, including repairing, refueling, or de-orbiting the satellite. The target must be captured and berthed before the servicing task starts. However, the attitude of the base may lean much and needs re-orientating after capturing. In this paper, a method is proposed to berth the target, and re-orientate the base at the same time, using manipulator motion only. Firstly, the system state is formed of the attitude quaternion and joint variables, and the joint paths are parameterized by sinusoidal functions. Then, the trajectory planning is transformed to an optimization problem. The cost function, defined according to the accuracy requirements of system variables, is the function of the parameters to be determined. Finally, we solve the parameters using the particle swarm optimization algorithm. Two typical cases of the spacecraft with a 6-DOF manipulator are dynamically simulated, one is that the variation of base attitude is limited; the other is that both the base attitude and the joint rates are constrained. The simulation results verify the presented method.

  12. "Floating shoulder" injuries.

    PubMed

    Heng, Kenneth

    2016-12-01

    "Floating shoulder" is a rare injury complex resulting from high-energy blunt force trauma to the shoulder, resulting in scapulothoracic dissociation. It is commonly associated with catastrophic neurovascular injury. Two cases of motorcyclists with floating shoulder injuries are described. PMID:26961729

  13. Wastewater treatment in a compact intensified wetland system at the Badboot: a floating swimming pool in Belgium.

    PubMed

    Van Oirschot, D; Wallace, S; Van Deun, R

    2015-09-01

    The Badboot (Dutch for swimming pool boat) is a floating swimming pool located in the city center of Antwerp in Belgium. The overall design consists of a recycled ferry boat that serves as a restaurant and next to that a newly built ship that harbours an Olympic size swimming pool, sun decks, locker rooms with showers, and a party space. A major design goal of the project was to make the ship as environmentally friendly as possible. To avoid discharge of contaminated waste water in the Antwerp docks, the ship includes onsite treatment of wastewater in a compact constructed wetland. The treatment wetland system was designed to treat wastewater from visitor locker rooms, showers, toilets, two bars, and the wastewater from the restaurant kitchen. Due to the limited space on board the ship, only 188 m(2) could be allocated to a wetland treatment system. As a result, part of the design included intensification of the wetland treatment process through the use of Forced Bed Aeration, which injects small quantities of air in a very uniform grid pattern throughout the wetland with a mechanical air compressor. The system was monitored between August 2012 and March 2013 (with additional sampling in the autumn of 2014). Flows and loads to the wetland were highly variable, but removal efficiency was extremely high; 99.5 % for chemical oxygen demand (COD), 88.6 % for total nitrogen and 97.2 % for ammonia. The treatment performance was assessed using a first-order, tanks-in-series model (the P-k-C* model) and found to be roughly equivalent to similar intensified wetlands operating in Germany. However, treatment performance was substantially better than data reported on passive wetlands, likely as a result of intensification. Even with mechanically assisted aeration, the total oxygen delivered to the treatment wetlands was insufficient to support conventional nitrification and denitrification, so it is likely that alternate nitrogen removal pathways, such as anammox, are

  14. Preparation and in vitro characterization of non-effervescent floating drug delivery system of poorly soluble drug, carvedilol phosphate.

    PubMed

    Srikanth Meka, Venkata; Wee Liang, Vanitha A P Hong; Dharmalingham, Senthil Rajan; Sheshala, Ravi; Gorajana, Adinarayana

    2014-12-01

    The objective of the study was to enhance the solubility of carvedilol phosphate and to formulate it into non-effervescent floating tablets using swellable polymers. Solid dispersions (SD) of carvedilol were prepared with hydrophilic carriers such as polyvinylpyrrolidone and poloxamer to enhance solubility. Non-effervescent floating tablets were prepared with a combination of optimized solid dispersions and release retarding polymers/swellable polymers such as xanthan gum and polyethylene oxide. Tablets were evaluated for physicochemical properties such as hardness, thickness and buoyancy. SD prepared with the drug to poloxamer ratio of 1:4 by melt granulation showed a higher dissolution rate than all other dispersions. Formulations containing 40 mg of polyethylene oxide (C-P40) and 50 mg xanthan gum (C-X50) were found to be best, with the drug retardation up to 12 hours. Optimized formulations were characterized using FTIR and DSC and no drug and excipient interactions were detected. PMID:25531788

  15. Vegetable Production System (Veggie)

    NASA Technical Reports Server (NTRS)

    Levine, Howard G.; Smith, Trent M.

    2016-01-01

    The Vegetable Production System (Veggie) was developed by Orbital Technologies Corp. to be a simple, easily stowed, and high growth volume yet low resource facility capable of producing fresh vegetables on the International Space Station (ISS). In addition to growing vegetables in space, Veggie can support a variety of experiments designed to determine how plants respond to microgravity, provide real-time psychological benefits for the crew, and conduct outreach activities. Currently, Veggie provides the largest volume available for plant growth on the ISS.

  16. Floating emitter solar cell

    NASA Technical Reports Server (NTRS)

    Chih, Sah (Inventor); Cheng, Li-Jen (Inventor)

    1987-01-01

    A front surface contact floating emitter solar cell transistor is provided in a semiconductor body (n-type), in which floating emitter sections (p-type) are diffused or implanted in the front surface. Between the emitter sections, a further section is diffused or implanted in the front surface, but isolated from the floating emitter sections, for use either as a base contact to the n-type semiconductor body, in which case the section is doped n+, or as a collector for the adjacent emitter sections.

  17. PESTICIDE PRODUCT INFORMATION SYSTEM (PPIS)

    EPA Science Inventory

    The Pesticide Product Information System (PPIS) contains information concerning all pesticide products registered in the United States. It includes registrant name and address, chemical ingredients, toxicity category, product names, distributor brand names, site/pest uses, pestic...

  18. Float zone experiments in space

    NASA Technical Reports Server (NTRS)

    Verhoeven, J. D.; Noack, M. A.; Gill, W. N.; Hau, C. C.

    1984-01-01

    The molten zone/freezing crystal interface system and all the mechanisms were examined. If Marangoni convection produces oscillatory flows in the float zone of semiconductor materials, such as silicon, then it is unlikely that superior quality crystals can be grown in space using this process. The major goals were: (1) to determine the conditions for the onset of Marangoni flows in molten tin, a model system for low Prandtl number molten semiconductor materials; (2) to determine whether the flows can be suppressed by a thin oxide layer; and (3) based on experimental and mathematical analysis, to predict whether oscillatory flows will occur in the float zone silicon geometry in space, and if so, could it be suppressed by thin oxide or nitride films. Techniques were developed to analyze molten tin surfaces in a UHV system in a disk float zone geometry to minimize buoyancy flows. The critical Marangoni number for onset of oscillatory flows was determined to be greater than 4300 on atomically clean molten tin surfaces.

  19. Floating Magnet Demonstration.

    ERIC Educational Resources Information Center

    Wake, Masayoshi

    1990-01-01

    A room-temperature demonstration of a floating magnet using a high-temperature superconductor is described. The setup and operation of the apparatus are described. The technical details of the effect are discussed. (CW)

  20. Micromechanisms with floating pivot

    DOEpatents

    Garcia, Ernest J.

    2001-03-06

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use floating pivot structures to relieve some of the problems encountered in the use of solid flexible pivots.

  1. Stabilized floating platforms

    DOEpatents

    Thomas, David G.

    1976-01-01

    The subject invention is directed to a floating platform for supporting nuclear reactors and the like at selected offshore sites. The platform is provided with a stabilizer mechanism which significantly reduces the effects of wave action upon the platform and which comprises a pair of relatively small floats attached by rigid booms to the platform at locations spaced therefrom for reducing wave pitch, acceleration, and the resonance period of the wave.

  2. Ultra-Deepwater Production Systems

    SciTech Connect

    K. L. Smith; M. E. Leveque

    2003-09-30

    This report includes technical progress made during the period October, 2002 through September, 2003. At the end of the second technical progress report, the ConocoPhillips opportunities to apply subsea processing in the Gulf of Mexico had been exhausted, and an alternative site was identified in Norway. This was a non-ConocoPhillips operated field, and the subsea processing was proposed as a phased development approach with 2-phase separation at the field, and then gas and liquids exported via pipeline to remote platform locations for processing. Although the unrisked economics were quite favorable, the risked economic evaluation compelled the operator to develop the field with the more conventional and proven Floating Production, Storage and Offloading (FPSO) option. Work on the subsea processing was suspended at this time. Discussions with DOE regarding two other step-change deepwater technologies ensued. One was an effort to develop a light-weight, high pressure composite production riser. A field demonstration of the design would then be performed by deploying a limited number of composite joints in a Gulf of Mexico deepwater development. The other was to begin the process of taking drilling with casing technology to the deepwater. This is called, ''close-tolerance liner drilling''. It was agreed that both technologies should be pursued, and the work began. During this reporting period, the initial production riser design had been completed and preliminary test sample components were being fabricated. Regarding the liner drilling, the sub-contractors were selected, the design basis was agreed and designs progressed towards meeting a projected first quarter, 2004 onshore test program.

  3. Offshore Code Comparison Collaboration, Continuation within IEA Wind Task 30: Phase II Results Regarding a Floating Semisubmersible Wind System: Preprint

    SciTech Connect

    Robertson, A.; Jonkman, J.; Vorpahl, F.; Popko, W.; Qvist, J.; Froyd, L.; Chen, X.; Azcona, J.; Uzungoglu, E.; Guedes Soares, C.; Luan, C.; Yutong, H.; Pengcheng, F.; Yde, A.; Larsen, T.; Nichols, J.; Buils, R.; Lei, L.; Anders Nygard, T.; et al.

    2014-03-01

    Offshore wind turbines are designed and analyzed using comprehensive simulation tools (or codes) that account for the coupled dynamics of the wind inflow, aerodynamics, elasticity, and controls of the turbine, along with the incident waves, sea current, hydrodynamics, and foundation dynamics of the support structure. This paper describes the latest findings of the code-to-code verification activities of the Offshore Code Comparison Collaboration, Continuation (OC4) project, which operates under the International Energy Agency (IEA) Wind Task 30. In the latest phase of the project, participants used an assortment of simulation codes to model the coupled dynamic response of a 5-MW wind turbine installed on a floating semisubmersible in 200 m of water. Code predictions were compared from load-case simulations selected to test different model features. The comparisons have resulted in a greater understanding of offshore floating wind turbine dynamics and modeling techniques, and better knowledge of the validity of various approximations. The lessons learned from this exercise have improved the participants? codes, thus improving the standard of offshore wind turbine modeling.

  4. Battery charging in float vs. cycling environments

    SciTech Connect

    COREY,GARTH P.

    2000-04-20

    In lead-acid battery systems, cycling systems are often managed using float management strategies. There are many differences in battery management strategies for a float environment and battery management strategies for a cycling environment. To complicate matters further, in many cycling environments, such as off-grid domestic power systems, there is usually not an available charging source capable of efficiently equalizing a lead-acid battery let alone bring it to a full state of charge. Typically, rules for battery management which have worked quite well in a floating environment have been routinely applied to cycling batteries without full appreciation of what the cycling battery really needs to reach a full state of charge and to maintain a high state of health. For example, charge target voltages for batteries that are regularly deep cycled in off-grid power sources are the same as voltages applied to stand-by systems following a discharge event. In other charging operations equalization charge requirements are frequently ignored or incorrectly applied in cycled systems which frequently leads to premature capacity loss. The cause of this serious problem: the application of float battery management strategies to cycling battery systems. This paper describes the outcomes to be expected when managing cycling batteries with float strategies and discusses the techniques and benefits for the use of cycling battery management strategies.

  5. Skylab floating ice experiment

    NASA Technical Reports Server (NTRS)

    Campbell, W. J. (Principal Investigator); Ramseier, R. O.; Weaver, R. J.; Weeks, W. F.

    1975-01-01

    The author has identified the following significant results. Coupling of the aircraft data with the ground truth observations proved to be highly successful with interesting results being obtained with IR and SLAR passive microwave techniques, and standard photography. Of particular interest were the results of the PMIS system which operated at 10.69 GHz with both vertical and horizontal polarizations. This was the first time that dual polarized images were obtained from floating ice. In both sea and lake ice, it was possible to distinguish a wide variety of thin ice types because of their large differences in brightness temperatures. It was found that the higher brightness temperature was invariably obtained in the vertically polarized mode, and as the age of the ice increases the brightness temperature increases in both polarizations. Associated with this change in age, the difference in temperature was observed as the different polarizations decreased. It appears that the horizontally polarized data is the most sensitive to variations in ice type for both fresh water and sea ice. The study also showed the great amount of information on ice surface roughness and deformation patterns that can be obtained from X-band SLAR observations.

  6. Impact on floating membranes

    NASA Astrophysics Data System (ADS)

    Vandenberghe, Nicolas; Duchemin, Laurent

    2016-05-01

    When impacted by a rigid body, a thin elastic membrane with negligible bending rigidity floating on a liquid pool deforms. Two axisymmetric waves radiating from the impact point propagate. First, a longitudinal wave front, associated with in-plane deformation of the membrane and traveling at constant speed, separates an outward stress-free domain from a stretched domain. Then, in the stretched domain a dispersive transverse wave travels at a speed that depends on the local stretching rate. The dynamics is found to be self-similar in time. Using this property, we show that the wave dynamics is similar to the capillary waves that propagate at a liquid-gas interface but with a surface tension coefficient that depends on impact speed. During wave propagation, we observe the development of a buckling instability that gives rise to radial wrinkles. We address the dynamics of this fluid-body system, including the rapid deceleration of an impactor of finite mass, an issue that may have applications in the domain of absorption of impact energy.

  7. [Optimization of a floating osmotic pump system of ambroxol hydrochloride using central composite design-response surface methodology and its pharmacokinetics in Beagle dogs].

    PubMed

    Zhao, Feng; Ma, Yin-Ling; Jin, Xiao-Li; Wang, Jing; Cao, De-Ying

    2011-12-01

    This paper reported that a new type of floating osmotic pump of ambroxol hydrochloride was designed. Third method apparatus (Chinese Pharmacopeia 2010, appendix XD) was employed to simultaneously evaluate the release and floating behavior in vitro. The system was optimized using central composite design-response surface methodology. Similar factor (f2) between the release profile of self-made formulation and the target release profile was chosen as dependent factor. The amount of glucose (A, mg), pore former (B, %) and weight of coating (C, %) were employed as independent factors. Optimized formulation was: A (100.99 mg), B (1.70%), C (4.21%). The value of f2 (89.14) was higher than that of market capsules (69.02) and self-made tablets (72.15). It was showed that self-made capsules possessed character of zero-order release (r = 0.994 4) and drug release completely (>90%). It was showed in result of in vivo study that tmax and Cmax of self-made capsules were significantly lower than that of market capsules and self-made tablets. The correlation coefficient between the fraction of absorption in vivo and the release rate in vitro was 0.985 1, and relative bioequivalence of self-made capsules was 110.77%. Accordingly, self-made capsules displayed obviously characteristics of controlled release both in vivo and in vitro. PMID:22375427

  8. Tethered float liquid level sensor

    DOEpatents

    Daily, III, William Dean

    2016-09-06

    An apparatus for sensing the level of a liquid includes a float, a tether attached to the float, a pulley attached to the tether, a rotation sensor connected to the pulley that senses vertical movement of said float and senses the level of the liquid.

  9. Compound floating pivot micromechanisms

    DOEpatents

    Garcia, Ernest J.

    2001-04-24

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.

  10. Floating patella associated with lymphoedema

    PubMed Central

    Vun, Shen Hwa; Bayam, Levent; Drampalos, Efstathios; Jesry, Mohammed; Fadel, George

    2015-01-01

    Ipsilateral injury of more than one component of the knee extensor apparatus is rare. It is mostly associated with previous trauma, surgery, immunosuppression therapy and systemic disease. We present the first documented case of a spontaneous bifocal disruption of the knee extensor apparatus (i.e. floating patella) associated with lymphoedema. This case highlights the importance of considering lymphoedema as another risk factor for rupture of the knee extensor apparatus. It also highlights the importance of assessing all components of the knee extensor apparatus in patients presenting with acute knee injuries. PMID:25802253

  11. Floating platform with monolithically formed float members and platform

    SciTech Connect

    Finsterwalder, U.

    1981-06-30

    Floating platforms for various offshore facilities are formed of float members monolithically connected to a superposed platform. The float members are spherically shaped and are formed of reinforced or prestressed concrete. The platform can be a hollow planar member or it can be curved in one or two directions, and the platforms are formed of prestressed concrete. Cylindrical shafts can be used to connect the spherically shaped floats and the platform. Individual floating platforms can be connected by expansion joints and used as a runway. The float members can be constructed at the shoreline, launched into the water and held in a regular pattern while decked over with the platform. After completion of the construction procedure, the floating platform can be moved to an offshore location for use.

  12. Optics for five-dimensional measurement for correction of vertical displacement error due to attitude of floating body in superconducting magnetic levitation system

    NASA Astrophysics Data System (ADS)

    Shiota, Fuyuhiko; Morokuma, Tadashi

    2006-09-01

    An improved optical system for five-dimensional measurement has been developed for the correction of vertical displacement error due to the attitude change of a superconducting floating body that shows five degrees of freedom besides a vertical displacement of 10mm. The available solid angle for the optical measurement is extremely limited because of the cryogenic laser interferometer sharing the optical window of a vacuum chamber in addition to the basic structure of the cryogenic vessel for liquid helium. The aim of the design was to develop a more practical as well as better optical system compared with the prototype system. Various artifices were built into this optical system and the result shows a satisfactory performance and easy operation overcoming the extremely severe spatial difficulty in the levitation system. Although the system described here is specifically designed for our magnetic levitation system, the concept and each artifice will be applicable to the optical measurement system for an object in a high-vacuum chamber and/or cryogenic vessel where the available solid angle for an optical path is extremely limited.

  13. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  14. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  15. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  16. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  17. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  18. Electrowetting in a water droplet with a movable floating substrate

    NASA Astrophysics Data System (ADS)

    Shahzad, Amir; Masud, A. R.; Song, Jang-Kun

    2016-05-01

    Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering.

  19. Electrowetting in a water droplet with a movable floating substrate.

    PubMed

    Shahzad, Amir; Masud, A R; Song, Jang-Kun

    2016-05-01

    Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering. PMID:27300973

  20. Recent advances in gastric floating drug delivery technology: a review.

    PubMed

    Pahwa, Rakesh; Bisht, Seema; Kumar, Vipin; Kohli, Kanchan

    2013-06-01

    Gastric floating drug delivery systems have been an avenue of considerable interest in terms of their immense potential for better pharmacotherapeutic interventions along with site-specific absorption. These buoyant systems significantly enhance the bioavailability and controlled delivery of several drug molecules. Scientific investigators have also carried out substantial research endeavours worldwide in order to design a more systematic and intellectual floating systems. The present manuscript is an attempt to highlight numerous recent advancements in the design of gastric floating drug delivery systems along with various available commercial preparations. Salient applications, characterization aspects and future perspectives of these multifarious systems have also been addressed. PMID:23808593

  1. Vibration characteristics of floating slab track

    NASA Astrophysics Data System (ADS)

    Kuo, Chen-Ming; Huang, Cheng-Hao; Chen, Yi-Yi

    2008-11-01

    Coupled equilibrium equations of suspended wheels and floating slab track system were solved with the fourth-order Runge-Kutta method to obtain the deflections, vibration velocities, and wheel-rail contact forces. The program was validated through several aspects. Cases with various vehicle speed, slab mass, and stiffness of slab bearing were analyzed to reveal the effects of slab bearing on track responses. The correlation between wheel-rail resonance and train speed was also discussed. It was found that rail deflections increase significantly as train speed increases. Although large slab mass may lower tuning frequency, it could also result in higher wheel-rail contact force and rail deflections. The floating slab track is effective in isolating loading above 10 Hz, which might present in some railway sections with irregularities. Adopting floating slab track for vibration control for environment along the railway may cause concerns about ride quality and track damages.

  2. Purified silicon production system

    DOEpatents

    Wang, Tihu; Ciszek, Theodore F.

    2004-03-30

    Method and apparatus for producing purified bulk silicon from highly impure metallurgical-grade silicon source material at atmospheric pressure. Method involves: (1) initially reacting iodine and metallurgical-grade silicon to create silicon tetraiodide and impurity iodide byproducts in a cold-wall reactor chamber; (2) isolating silicon tetraiodide from the impurity iodide byproducts and purifying it by distillation in a distillation chamber; and (3) transferring the purified silicon tetraiodide back to the cold-wall reactor chamber, reacting it with additional iodine and metallurgical-grade silicon to produce silicon diiodide and depositing the silicon diiodide onto a substrate within the cold-wall reactor chamber. The two chambers are at atmospheric pressure and the system is open to allow the introduction of additional source material and to remove and replace finished substrates.

  3. The SPOOKI post production system

    NASA Astrophysics Data System (ADS)

    Beauchemin, M.; Klasa, M.; Fortier, S.; Fortin, F.; Hardy, G.; Pelletier, L.; Edouard, S.; Archambault, B.; Yazidi, H.

    2010-09-01

    The Canadian Meteorological Centre (CMC) delivers a large number of numerical weather prediction products to the various weather offices and clients throughout Canada and abroad. The current post production system was built according to the needs and ideology of the 1980's and it is becoming obsolete with time. Its cumbersome architecture is difficult to maintain and requires a lot of human and computing resources. The "Weather Elements" section of CMC is aware of the problems associated with its maintenance in the long term and has therefore decided to review in depth the whole approach to the operational post production. The analysis of present and future needs have led to the development of an innovative concept in the operational production field inspired by the "Plug and Play" process. SPOOKI (Système de Production Orienté-Objet contennant une Kyrielle d'Informations - Object oriented production system containing a myriad of information) was created in its present form in 2007. It is based on a modular approach where each plug-in component is specialized, reusable and autonomous. These object oriented programming characteristics greatly simplify the maintenance of the system. Particular attention was also given to create a user-friendly system for novice users. An experimental version of SPOOKI is currently running in development mode and an operational one is planned to be implemented in the coming year. The poster presentation will describe SPOOKI, the future CMC operational post production system. Several examples of usage will be shown.

  4. Formulation and evaluation of novel coated floating tablets of bergenin and cetirizine dihydrochloride for gastric delivery.

    PubMed

    He, Shuang; Li, Feng; Zhou, Dan; Du, Junrong; Huang, Yuan

    2012-10-01

    A novel coated gastric floating drug-delivery system (GFDDS) of bergenin (BN) and cetirizine dihydrochloride (CET) was developed. First, the pharmacodynamic studies were performed and the results revealed that the new compounds of bergenin/cetirizine dihydrochloride had comparative efficacy as commercial products (bergenin/chlorphenamine maleate) but with fewer side effects on central nervous system (CNS). Subsequently, bergenin was formulated as an extended-release core tablet while cetirizine dihydrochloride was incorporated into the gastric coating film for immediate release. The formulation of GFDDS was optimized by CET content uniformity test, in vitro buoyancy and drug release. Herein, the effects of sodium bicarbonate (effervescent), hydroxypropyl methylcellulose (HPMC, matrix polymer) and coating weight gain were investigated respectively. The optimized GFDDS exhibited good floating properties (buoyancy lag time < 2 min; floating duration > 10 h) and satisfactory drug-release profiles (immediate release of CET in 10 min and sustained release of BN for 12 h). In vivo gamma scintigraphy proved that the optimized GFDDS could retain in the stomach with a prolonged gastric retention time (GRT) of 5 h, and the coating layer showed no side effect for gastric retention. The novel coated gastric floating drug-delivery system offers a new approach to enhance BN's absorption at its absorption site and the efficacy of both CET and BN. PMID:22206469

  5. Effects of tilt angle of mirror-lamp system on shape of solid-liquid interface of silicon melt during floating zone growth using infrared convergent heating

    NASA Astrophysics Data System (ADS)

    Hossain, Md. Mukter; Watauchi, Satoshi; Nagao, Masanori; Tanaka, Isao

    2016-01-01

    The tilt effects of the mirror-lamp (M-L) system on the shape of the interface of the silicon molten zone formed during growth using the infrared convergent heating floating zone method were studied at various positions of the M-L system. The stability and the interfaces of the molten zone formed in the tilted condition were compared with those in the no tilt condition. The molten zone appeared to be more stabilized in the tilted condition than in the no tilt condition. However, the conventional parameters characterizing the interface shape such as convexities (h/r), gap and zone length (L) were almost independent of the tilt angle (θ) of the M-L system and insufficient to discuss the tilting effects on the molten zone shape. The curvature of the solid-liquid interface was affected by the θ. New characterizing parameters such as the growth interface and triple point angles (δ and TPA, respectively) were effective to quantitatively describe the tilting effects on the interface shape. With increase of the θ, the δ was decreased and the TPA was increased in both the feed and crystal sides. A silicon crystal of 45 mm in diameter was grown successfully in the tilted condition.

  6. A methodology for risk analysis based on hybrid Bayesian networks: application to the regasification system of liquefied natural gas onboard a floating storage and regasification unit.

    PubMed

    Martins, Marcelo Ramos; Schleder, Adriana Miralles; Droguett, Enrique López

    2014-12-01

    This article presents an iterative six-step risk analysis methodology based on hybrid Bayesian networks (BNs). In typical risk analysis, systems are usually modeled as discrete and Boolean variables with constant failure rates via fault trees. Nevertheless, in many cases, it is not possible to perform an efficient analysis using only discrete and Boolean variables. The approach put forward by the proposed methodology makes use of BNs and incorporates recent developments that facilitate the use of continuous variables whose values may have any probability distributions. Thus, this approach makes the methodology particularly useful in cases where the available data for quantification of hazardous events probabilities are scarce or nonexistent, there is dependence among events, or when nonbinary events are involved. The methodology is applied to the risk analysis of a regasification system of liquefied natural gas (LNG) on board an FSRU (floating, storage, and regasification unit). LNG is becoming an important energy source option and the world's capacity to produce LNG is surging. Large reserves of natural gas exist worldwide, particularly in areas where the resources exceed the demand. Thus, this natural gas is liquefied for shipping and the storage and regasification process usually occurs at onshore plants. However, a new option for LNG storage and regasification has been proposed: the FSRU. As very few FSRUs have been put into operation, relevant failure data on FSRU systems are scarce. The results show the usefulness of the proposed methodology for cases where the risk analysis must be performed under considerable uncertainty. PMID:25041168

  7. Float processing of high-temperature complex silicate glasses and float baths used for same

    NASA Technical Reports Server (NTRS)

    Cooper, Reid Franklin (Inventor); Cook, Glen Bennett (Inventor)

    2000-01-01

    A float glass process for production of high melting temperature glasses utilizes a binary metal alloy bath having the combined properties of a low melting point, low reactivity with oxygen, low vapor pressure, and minimal reactivity with the silicate glasses being formed. The metal alloy of the float medium is exothermic with a solvent metal that does not readily form an oxide. The vapor pressure of both components in the alloy is low enough to prevent deleterious vapor deposition, and there is minimal chemical and interdiffusive interaction of either component with silicate glasses under the float processing conditions. Alloys having the desired combination of properties include compositions in which gold, silver or copper is the solvent metal and silicon, germanium or tin is the solute, preferably in eutectic or near-eutectic compositions.

  8. The Floating Ball Paradox

    NASA Astrophysics Data System (ADS)

    Wente, Henry C.

    2008-11-01

    In capillary theory there are two kinds of surface tension. There is the surface tension at the interface between two immiscible fluids. Thomas Young [9] also allowed for there to be a surface tension associated with a liquid-solid interface. He proceeded to use a balance of forces argument to derive the well-known contact angle condition along a liquid-liquid-solid intersection. The validity of this argument has recently been called into question by R. Finn [6]. A floating ball experiment discussed in that paper leads to an apparent paradox. We address this issue.

  9. Float level switch for a nuclear power plant containment vessel

    DOEpatents

    Powell, James G.

    1993-01-01

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.

  10. Float level switch for a nuclear power plant containment vessel

    DOEpatents

    Powell, J.G.

    1993-11-16

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures.

  11. Defining the IEEE-854 floating-point standard in PVS

    NASA Technical Reports Server (NTRS)

    Miner, Paul S.

    1995-01-01

    A significant portion of the ANSI/IEEE-854 Standard for Radix-Independent Floating-Point Arithmetic is defined in PVS (Prototype Verification System). Since IEEE-854 is a generalization of the ANSI/IEEE-754 Standard for Binary Floating-Point Arithmetic, the definition of IEEE-854 in PVS also formally defines much of IEEE-754. This collection of PVS theories provides a basis for machine checked verification of floating-point systems. This formal definition illustrates that formal specification techniques are sufficiently advanced that is is reasonable to consider their use in the development of future standards.

  12. Study of Novel Floating-Gate Oxide Semiconductor Memory Using Indium-Gallium-Zinc Oxide for Low-Power System-on-Panel Applications

    NASA Astrophysics Data System (ADS)

    Yamauchi, Yoshimitsu; Kamakura, Yoshinari; Isagi, Yousuke; Matsuoka, Toshimasa; Malotaux, Satoshi

    2013-09-01

    A novel floating-gate oxide semiconductor (FLOTOS) memory using a wide-band-gap indium-gallium-zinc oxide (IGZO) is presented for low-power system-on-panel applications. An IGZO thin-film-transistor (TFT) is used as a memory transistor for controlling read current as well as a switching transistor for storing charges in a storage capacitor (Cs). The FLOTOS memory is fabricated using a standard IGZO TFT process without any additional process or mask steps. The proposed precharge-assisted threshold voltage compensation technique makes it possible to realize an infinite number of write cycles and a low-power write operation with a bit-line voltage of 5 V. Furthermore, excellent data retention longer than 10 h is obtained at 60 °C even under the worst bias-stress condition of read operation with the ultra low off-state leakage (2.8×10-20 A/µm) of the IGZO TFTs, which is estimated to be smaller by more than 7 orders of magnitude than that of polycrystalline silicon TFTs.

  13. Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia).

    PubMed

    Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N; Klepal, Waltraud

    2015-02-01

    Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water. PMID:25657839

  14. Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia)

    PubMed Central

    Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N.; Klepal, Waltraud

    2015-01-01

    Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water. PMID:25657839

  15. Floating Crane YD82 general view. Date taken unknown. Taken ...

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

    Floating Crane YD-82 - general view. Date taken unknown. Taken by Pearl Harbor photographer. Crane Division Collection - U.S. Naval Base, Pearl Harbor, Exterior Cranes, Waterfront Crane Track System, Pearl City, Honolulu County, HI

  16. Preview of Mars Curiosity Parade Float - Duration: 33 seconds.

    NASA Video Gallery

    Jim Green, Director of the Science Mission Directorate Planetary Systems Division at NASA Headquarters, describes the replica of the Mars Curiosity Rover on the second NASA float in Monday's inaugu...

  17. 16. EAST ELEVATION OF FLOAT HOUSE AND FISH WATER RELEASE ...

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

    16. EAST ELEVATION OF FLOAT HOUSE AND FISH WATER RELEASE OUTLET. PART OF ENERGY DISSIPATING BAFFLE PIER SYSTEM IS VISIBLE AT LEFT. - Pit 4 Diversion Dam, Pit River west of State Highway 89, Big Bend, Shasta County, CA

  18. Does It Sink or Float?

    ERIC Educational Resources Information Center

    McDonald, Judith Richards

    2012-01-01

    This activity is designed to teach prekindergarten to second grade students about the concept of sink or float through an inquiry activity. Students will use familiar objects to predict and test the properties of sink and float. Background information is offered to teachers to assist them with this activity. This lesson begins with an engaging…

  19. Multi-input and binary reproducible, high bandwidth floating point adder in a collective network

    DOEpatents

    Chen, Dong; Eisley, Noel A; Heidelberger, Philip; Steinmacher-Burow, Burkhard

    2015-03-10

    To add floating point numbers in a parallel computing system, a collective logic device receives the floating point numbers from computing nodes. The collective logic devices converts the floating point numbers to integer numbers. The collective logic device adds the integer numbers and generating a summation of the integer numbers. The collective logic device converts the summation to a floating point number. The collective logic device performs the receiving, the converting the floating point numbers, the adding, the generating and the converting the summation in one pass. One pass indicates that the computing nodes send inputs only once to the collective logic device and receive outputs only once from the collective logic device.

  20. Radiation Issues and Applications of Floating Gate Memories

    NASA Technical Reports Server (NTRS)

    Scheick, L. Z.; Nguyen, D. N.

    2000-01-01

    The radiation effects that affect various systems that comprise floating gate memories are presented. The wear-out degradation results of unirradiated flash memories are compared to irradiated flash memories. The procedure analyzes the failure to write and erase caused by wear-out and degradation of internal charge pump circuits. A method is described for characterizing the radiation effects of the floating gate itself. The rate dependence, stopping power dependence, SEU susceptibility and applications of floating gate in radiation environment are presented. The ramifications for dosimetry and cell failure are discussed as well as for the long term use aspects of non-volatile memories.

  1. Floating mirror mount

    SciTech Connect

    Koop, D.E.

    1989-01-03

    This patent describes a floating mirror mount for a mirror of a laser is described consisting of: a mirror having a front surface and a back surface, a keeper encircling the mirror and having a peripheral flange engaging the front surface of the mirror when the mirror is not installed in a laser, a retainer positioned rearwardly of the back surface of the mirror and connected to the keeper and having a spring seating surface, spring means engageable with the spring seating surface of the retainer for exerting a resilient biasing force on the mirror, and fastening means for connecting the retainer to the mirror positioning structure of the laser on installation of the mirror mount in the laser.

  2. Floating into Deep Space

    NASA Astrophysics Data System (ADS)

    La Frenais, R.; Saraceno, T.; Powell, J.

    2014-04-01

    Is it possible for spaceflight to become more sustainable? Artist and architect Tomas Saraceno proposes a long-term artscience research project based on his initial work with solar balloons to join with the efforts of engineers such as John Powell, working on the Airship to Orbit experiments, which describe a three stage process of using airships to fly to a large suborbital "Dark Sky Station' then literally floating into orbit with additional electrical and chemical propulsion. (See: http://www.jpaerospace.com) In his artworks Tomás Saraceno proposes cell-like flying cities as possible architectonic living spaces in direct reference to Buckminster Fuller's Cloud Nine (circa 1960). The fantastic architectural utopia Cloud Nine consists of a freely floating sphere measuring one mile in diameter that offers living space to several autonomous communities encompassing thousands of inhabitants each. The notion of the cloud is essential to the artist's work. The cloud as metaphor stands for artistic intention, for the meaning of territory and border in today's (urban) society, and for exploring possibilities for the sustainable development of the human living environment. In Saraceno's work this environment is not limited to the earth, but is explicitly conceived to reach into outer space. (Biomimetic Constructions- On the works of Tomás Saraceno By Katharina Schlüter) Saraceno is also interested in human factors experiments using his existing constructions as analogue environments for living on Mars and is proposing carry out a series of workshops, experiments and solar balloon launces in White Sands desert in early 2016 in collaboration with the curator Dr Rob La Frenais, the Rubin Center at The University of Texas at El Paso and various scientific partners.

  3. Iron production maintenance effectiveness system

    SciTech Connect

    Augstman, J.J.

    1996-12-31

    In 1989, an internal study in the Coke and Iron Maintenance Department identified the opportunities available to increase production, by decreasing unscheduled maintenance delays from 4.6%. A five year front loaded plan was developed, and presented to the company president. The plan required an initial investment of $1.4 million and a conservative break-even point was calculated to be 2.5 years. Due to budget restraints, it would have to be self-funded, i.e., generate additional production or savings, to pay for the program. The program began in 1991 at number 2 coke plant and the blast furnaces. This paper will describe the Iron Production Maintenance Effectiveness System (ME), which began with the mechanical and pipefitting trades.

  4. Considerations on the effects of tidal regimes in the movement of floating litter in an estuarine environment: Case study of the estuarine system of Santos-São Vicente, Brazil.

    PubMed

    Fernandino, Gerson; Elliff, Carla Isobel; Frutuoso, Gabriela Amado; Silva, Eric Vinícius Nascimento Malaquias da; Gama, Guilherme Santiago; Sousa, João Henrique de Oliveira; Silva, Iracema Reimão

    2016-09-15

    Floating litter in the estuarine system of Santos-São Vicente is common and is part of day-to-day activities of various users of the area. The objective of the present study was to carry out a quali-quantitative evaluation of the occurrence of floating litter, to infer their sources, and to identify environmental factors that are likely to control occurrence and distribution, with particular emphasis on the effects of tidal regimes. Six sampling stations were selected along the aforementioned estuary and visited monthly between July 2010 and January 2012. Floating litter was counted from a fixed sampling station. Plastics prevailed (89.64%) and their main source was domestic activities (55.41%). More litter was found during ebb spring tides, with higher concentrations obeying confluence patterns of the estuary's channels. Results indicated that occurrence can be attributed to the deficiency in basic sewage system in the area and the deliberate disposal into the estuary by the local population. PMID:27263980

  5. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    William S. McPhee

    1999-05-31

    The objective of this project is to improve the productivity and lower the expense of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCBs, and lead-based paint and provides worker protection by continuously recycling the material and dust for the decontamination tasks. The proposed work would increase the cleaning rate and provide safe and cost-effective decontamination of the DOE sites. This work focuses on redesigning and improving existing vacuum blasting technology including blast head nozzles, ergonomic handling of the blast head by reducing its weight; brush-ring design, vacuum level regulator, efficiency of the dust separator, and operational control sensors. The redesign is expected to enhance the productivity and economy of the vacuum blasting system by at least 50% over current vacuum blasting systems. There are three phases in the project. Phase I consists of developing and testing mathematical models. Phase II consists of pre-prototype design and fabrication and pre-prototype unit testing. Phase III consists of prototype design and field verification testing. In phase I, mathematical models are developed and analyzed for the nozzle, blast head, wind curtain, and dust separator, first as individual devices and then combined as an integrated model. This allows study of respective airflow and design parameters. The Contractor shall, based on the results of the mathematical modeling studies, design experimental models of the components and test these models. In addition, the Contractor shall develop sensors to detect the relationship of the blast head to the blast surfaces and controls to minimize the dependency on an operator's skill and judgment to obtain optimum positioning, as well as real-time characterization sensors to determine as the blast head is moving the depth to which coatings must be removed, thereby improving production and minimizing waste. In phase II, the Contractor shall design and

  6. Ipsilateral Floating Hip and Floating Knee - A Rare Entity

    PubMed Central

    Yashavantha Kumar, C; Nalini, K B; Nagaraj, Prashanth; Jawali, Abhijith

    2013-01-01

    Introduction: Ipsilateral floating hip and floating knee are very rare injuries. These injuries so uncommon that only three cases of similar kind have been reported. These injuries are due to high velocity injuries following motor vehicle accidents. Management of such complex injuries is a challenging task even in experienced hands as there are no standard treatment guidelines for such fractures. Case Report: We hereby report a 20 yr old male who sustained ipsilateral floating hip and ipsilateral floating knee injuries following motor vehicle accident. Patient was stabilized initially and later taken up for surgery. Patient was treated with interlocking nail for femur and tibia in the same sitting whereas acetabulam fracture was managed conservatively. At five months all the fractures united well with restoration of good range of motion in both hip and knee Conclusion: Ipsilateral floating knee and floating hip are very rare injuries seen following high velocity motor vehicle accidents. There are no standard guidelines for treatment of those fractures as only a few cases of similar kind have been reported in literature. Early fixation and aggressive mobilization ensures fracture union and fewer complications. PMID:27298908

  7. Chemical production processes and systems

    DOEpatents

    Holladay, Johnathan E.; Muzatko, Danielle S.; White, James F.; Zacher, Alan H.

    2014-06-17

    Hydrogenolysis systems are provided that can include a reactor housing an Ru-comprising hydrogenolysis catalyst and wherein the contents of the reactor is maintained at a neutral or acidic pH. Reactant reservoirs within the system can include a polyhydric alcohol compound and a base, wherein a weight ratio of the base to the compound is less than 0.05. Systems also include the product reservoir comprising a hydrogenolyzed polyhydric alcohol compound and salts of organic acids, and wherein the moles of base are substantially equivalent to the moles of salts or organic acids. Processes are provided that can include an Ru-comprising catalyst within a mixture having a neutral or acidic pH. A weight ratio of the base to the compound can be between 0.01 and 0.05 during exposing.

  8. Chemical production processes and systems

    SciTech Connect

    Holladay, Johnathan E; Muzatko, Danielle S; White, James F; Zacher, Alan H

    2015-04-21

    Hydrogenolysis systems are provided that can include a reactor housing an Ru-comprising hydrogenolysis catalyst and wherein the contents of the reactor is maintained at a neutral or acidic pH. Reactant reservoirs within the system can include a polyhydric alcohol compound and a base, wherein a weight ratio of the base to the compound is less than 0.05. Systems also include the product reservoir comprising a hydrogenolyzed polyhydric alcohol compound and salts of organic acids, and wherein the moles of base are substantially equivalent to the moles of salts or organic acids. Processes are provided that can include an Ru-comprising catalyst within a mixture having a neutral or acidic pH. A weight ratio of the base to the compound can be between 0.01 and 0.05 during exposing.

  9. Ultra-Deepwater Production Systems

    SciTech Connect

    Ken L. Smith; Marc E. Leveque

    2005-05-31

    The report herein is a summary of the work performed on three projects to demonstrate hydrocarbon drilling and production methods applicable to deep and ultra deepwater field developments in the Gulf of Mexico and other like applications around the world. This work advances technology that could lead to more economic development and exploitation of reserves in ultra-deep water or remote areas. The first project is Subsea Processing. Its scope includes a review of the ''state of the art'' in subsea components to enable primary production process functions such as first stage liquids and gas separation, flow boosting, chemical treatment, flow metering, etc. These components are then combined to allow for the elimination of costly surface production facilities at the well site. A number of studies were then performed on proposed field development projects to validate the economic potential of this technology. The second project involved the design and testing of a light weight production riser made of composite material. The proposed design was to meet an actual Gulf of Mexico deepwater development project. The various engineering and testing work is reviewed, including test results. The third project described in this report encompasses the development and testing of a close tolerance liner drilling system, a new technology aimed at reducing deepwater drilling costs. The design and prototype testing in a test well are described in detail.

  10. Sterile Product Packaging and Delivery Systems.

    PubMed

    Akers, Michael J

    2015-01-01

    Both conventional and more advanced product container and delivery systems are the focus of this brief article. Six different product container systems will be discussed, plus advances in primary packaging for special delivery systems and needle technology. PMID:26891564

  11. Floating orbital molecular dynamics simulations.

    PubMed

    Perlt, Eva; Brüssel, Marc; Kirchner, Barbara

    2014-04-21

    We introduce an alternative ab initio molecular dynamics simulation as a unification of Hartree-Fock molecular dynamics and the floating orbital approach. The general scheme of the floating orbital molecular dynamics method is presented. Moreover, a simple but sophisticated guess for the orbital centers is provided to reduce the number of electronic structure optimization steps at each molecular dynamics step. The conservation of total energy and angular momentum is investigated in order to validate the floating orbital molecular dynamics approach with and without application of the initial guess. Finally, a water monomer and a water dimer are simulated, and the influence of the orbital floating on certain properties like the dipole moment is investigated. PMID:24600690

  12. NULL convention floating point multiplier.

    PubMed

    Albert, Anitha Juliette; Ramachandran, Seshasayanan

    2015-01-01

    Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation. PMID:25879069

  13. NULL Convention Floating Point Multiplier

    PubMed Central

    Ramachandran, Seshasayanan

    2015-01-01

    Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation. PMID:25879069

  14. High voltage switches having one or more floating conductor layers

    SciTech Connect

    Werne, Roger W.; Sampayan, Stephen; Harris, John Richardson

    2015-11-24

    This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

  15. Electrically floating, near vertical incidence, skywave antenna

    SciTech Connect

    Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

    2014-07-08

    An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

  16. Comparative evaluation of single and bilayered lamotrigine floating tablets

    PubMed Central

    Lakshmi, PK; Sridhar, M; Shruthi, B

    2013-01-01

    Aim: The purpose of this study was to prepare lamotrigine (LM) bilayered and single layered floating tablets and to compare their release profiles. Materials and Methods: LM floating tablets were prepared by direct compression method. Drug, hydroxy propyl methyl cellulose K4M, lactose monohydrate and polyvinylpyrrolidone K30 constitute controlled release layer components and floating layer components includes polymers and sodium bicarbonate. The prepared tablets were evaluated for physicochemical parameters such as hardness, friability, weight variation, thickness, floating lag time (FLT), floating time, in vitro buoyancy study, in vitro release studies. The drug-polymer interaction was studied by fourier transform infrared and differential scanning calorimetry. Results and Discussion: The FLT of all the formulations were within the prescribed limits (<3 min). When ethyl cellulose was used as floating layer component, tablets showed good buoyancy effect but eroded within 6-8 h. Hence it was replaced with hydroxypropyl cellulose -M hydrophilic polymer, which showed good FLT and floating duration for 16 h. Formulation LFC4 was found to be optimized with dissolution profile of zero order kinetics showing fickian diffusion. A comparative study of bilayered and single layered tablets of LM showed a highest similarity factor of 83.03, difference factor of 2.74 and t-test (P < 0.05) indicates that there is no significant difference between them. Conclusion: Though bilayered tablet possess many advantages, single layered tablet would be economical, cost-effective and reproducible for large scale production in the industry. However, the results of present study demonstrated that the in vitro development of bilayered gastro retentive floating tablets with controlled drug release profile for LM is feasible. PMID:24167788

  17. Ultra-Deepwater Production Systems

    SciTech Connect

    K. L. Smith; M. E. Leveque

    2004-09-30

    This report includes technical progress made during the period October, 2003 through September, 2004. At the end of the last technical progress report, the subsea processing aspects of the work program had been dropped due to the lack of commercial opportunity within ConocoPhillips, and the program had been redirected towards two other promising deepwater technologies: the development and demonstration of a composite production riser, and the development and testing of a close-tolerance liner drilling system. This report focuses on these two technologies.

  18. Designing a year-round production system for offshore Labrador

    SciTech Connect

    Jozan, M.M.; Wetzel, V.F.

    1980-08-01

    Of the various production schemes under consideration for use in the iceberg-plagued Labrador Sea, two seem technically feasible in the medium term (5-10 years): a quick-disconnect floating platform equipped with an ice-cutting device and a fixed structure mounted on an artificial island or submerged mound. The first alternative would be a seasonal production system relying on a dynamically positioned platform that could be easily disconnected from the riser when threatened by an oncoming iceberg; smaller ice floes would be broken up by the platform's ice cutter. The most feasible fixed-structure plan is to build a conventional platform on an artificial island or, in deeper waters, on a submerged mound. This alternative offers the room needed for the processing and liquefaction facilities required for tanker transport of natural gas. Labrador Sea hydrocarbons will most likely be transported by tankers rather than pipelines until designers devise means of protecting the pipe from iceberg scour and crossing the deep marginal trough.

  19. Floating into Thin Air

    SciTech Connect

    Hazi, A U

    2007-02-06

    On May 18, 2005, a giant helium balloon carrying the High Energy Focusing Telescope (HEFT) sailed into the spring sky over the deserts of New Mexico. The spindly steel and aluminum gondola that houses the optics, detectors, and other components of the telescope floated for 25 hours after its launch from Fort Sumner, New Mexico. For 21 of those hours, the balloon was nearly 40 kilometers above Earth's surface--almost four times higher than the altitude routinely flown by commercial jet aircraft. In the upper reaches of Earth's atmosphere, HEFT searched the universe for x-ray sources from highly energetic objects such as binary stars, galaxy clusters, and supermassive black holes. Before landing in Arizona, the telescope observed and imaged a dozen scientific targets by capturing photons emitted from these objects in the high-energy (hard) x-ray range (above 10 kiloelectronvolts). Among these targets were the Crab synchrotron nebula, the black hole Cygnus X-1 (one of the brightest x-ray sources in the sky), and the blazar 3C454.3. The scientific data gathered from these targets are among the first focused hard x-ray images returned from high altitudes.

  20. Multiview autosterescopic display with floating real image

    NASA Astrophysics Data System (ADS)

    Kakeya, Hideki; Kobe, Naoto; Kasano, Hidehiro

    2004-05-01

    This paper proposes multiview version of autostereoscopic display FLOATS (Fresnel Lens based Optical Apparatus for Touchable-distance Stereoscopy), which combines generation of floating real image and parallax presentation to show realistic 3-D image within the viewer's reach. Earlier versions of FLOATS have required a head tracker, physical motion control of filters or mirrors, and transformation of image in accordance with the viewer's motion to keep on presenting different images to each eye. To do away with these requirements, we propose two methods which realize multiview presentation to the viewer. One method is to use multiple LCD panels and multiple fixed mirrors instead of mobile mirrors. The other method is to use mutiple projectors, fly-eye lenses, and fresnel lenses. Though the former system doesn't cost much, it is not practical to present more than 10 views. In the latter system it is practical to present more than 30 views, which can realize presentation of both horizontal and vertical parallax. With this technology the viewers can perceive undistorted 3-D space from any angle, which makes it possible for multiple viewers to observe 3-D image at consistent position from different angles at the same time.

  1. Borofloat and Starphire Float Glasses: A Comparison

    SciTech Connect

    Wereszczak, Andrew A.; Anderson Jr., Charles E.

    2014-10-28

    Borofloat® borosilicate float glass and Starphire® soda-lime silicate float glass are used in transparent protective systems. They are known to respond differently in some ballistic and triaxial loading conditions, and efforts are underway to understand the causes of those differences. Toward that, a suite of test and material characterizations were completed in the present study on both glasses so to identify what differences exist among them. Compositional, physical properties, elastic properties, flaw size distributions and concentrations, tensile/flexure strength, fracture toughness, spherical indentation and hardness, transmission electron microscopy, striae, high pressure responses via diamond anvil cell testing, laser shock differences, and internal porosity were examined. Differences between these two float glasses were identified for many of these properties and characteristics, and the role of three (striae, high pressures where permanent densification can initiate, and sub-micron-sized porosity) lack understanding and deserve further attention. Lastly, the contributing roles of any of those properties or characteristics to triaxial or ballistic loading responses are not definitive; however, they provide potential correlations that may lead to improved understanding and management of loading responses in glasses used in transparent protective systems.

  2. Borofloat and Starphire Float Glasses: A Comparison

    DOE PAGESBeta

    Wereszczak, Andrew A.; Anderson Jr., Charles E.

    2014-10-28

    Borofloat® borosilicate float glass and Starphire® soda-lime silicate float glass are used in transparent protective systems. They are known to respond differently in some ballistic and triaxial loading conditions, and efforts are underway to understand the causes of those differences. Toward that, a suite of test and material characterizations were completed in the present study on both glasses so to identify what differences exist among them. Compositional, physical properties, elastic properties, flaw size distributions and concentrations, tensile/flexure strength, fracture toughness, spherical indentation and hardness, transmission electron microscopy, striae, high pressure responses via diamond anvil cell testing, laser shock differences, andmore » internal porosity were examined. Differences between these two float glasses were identified for many of these properties and characteristics, and the role of three (striae, high pressures where permanent densification can initiate, and sub-micron-sized porosity) lack understanding and deserve further attention. Lastly, the contributing roles of any of those properties or characteristics to triaxial or ballistic loading responses are not definitive; however, they provide potential correlations that may lead to improved understanding and management of loading responses in glasses used in transparent protective systems.« less

  3. Evaluation and floating enhancement of levodopa sustained release floating minitablets coated with insoluble acrylic polymer.

    PubMed

    Goole, J; Amighi, K; Vanderbist, F

    2008-08-01

    This article describes the in vitro evaluation and the enhancement of the floating properties of coated sustained release (SR) minitablets (MTs). The evaluated system consisted of a 3-mm drug-containing gas-generating core prepared by melt granulation and subsequent compression, which was then coated with a flexible polymeric membrane. Eudragit RL30D and acetyl triethylcitrate were used as a film former and a plasticizer, respectively. The coating level was fixed at 20% (wt/wt). The optimally coated floating MTs floated within 10 min and remained buoyant for more than 13 h, regardless of the pH of the test medium. By evaluating the dissolution profiles of levodopa at different pH, it was found that the release of levodopa was sustained for more than 12 h regardless of the pH, even if the coating did not cancel the effect of the pH-dependent solubility of the active drug. Finally, the robustness of the coated floating MTs was assessed by testing the drug release variability in function of the stirring conditions during dissolution tests. PMID:18618310

  4. Development and in vivo floating behavior of verapamil HCl intragastric floating tablets.

    PubMed

    Patel, Anand; Modasiya, Moin; Shah, Dushyant; Patel, Vishnu

    2009-01-01

    A novel gastro retentive controlled release drug delivery system of verapamil HCl was formulated in an effort to increase the gastric retention time of the dosage form and to control drug release. Hydroxypropylmethylcellulose (HPMC), carbopol, and xanthan gum were incorporated for gel-forming properties. Buoyancy was achieved by adding an effervescent mixture of sodium bicarbonate and anhydrous citric acid. In vitro drug release studies were performed, and drug release kinetics was evaluated using the linear regression method. The optimized intragastric floating tablet composed of 3:2 of HPMC K4M to xanthan gum exhibited 95.39% drug release in 24 h in vitro, while the buoyancy lag time was 36.2 s, and the intragastric floating tablet remained buoyant for >24 h. Zero-order and non-Fickian release transport was confirmed as the drug release mechanism from the optimized formulation (F7). X-ray studies showed that total buoyancy time was able to delay the gastric emptying of verapamil HCl intragastric floating tablet in mongrel dogs for more than 4 h. Optimized intragastric floating tablet showed no significant change in physical appearance, drug content, total buoyancy time, or in vitro dissolution pattern after storage at 40 degrees C/75% relative humidity for 3 months. PMID:19296224

  5. Floating intake reduces pump damage

    SciTech Connect

    Kronig, A.

    1993-12-31

    The solution to a costly sand erosion problem at the Grande Dixence hydroelectric project in Switzerland turned out to be as simple as a floating pump. The 726-MW Grande Dixence project drains a 350-square-kilometer reach of the Zermatt and Herens valleys in the southwestern Swiss Alps. About half of the drainage area is covered by active glaciers. Because the glaciers in Zermatt Valley are so low in altitude, their water is collected in Z`mutt Reservoir at the base of the Matterhorn, then pumped up 500 meters for transport to the main Grande Disence Reservoir near Sion. The glacier water is heavily laden with sand. In spite of a gravel pass and a desilter, the 700,000-acubic-meter Z`mutt Reservoir receives large quantities of sand. The sand tends to remain in solution because of the low water temperatures (1 to 2 degrees Centigrade). In the original intake system, the sand would be sucked into the pump intakes, causing extensive erosion to the pump wheels and an expensive yearly program of repair. (Pump damage averaged 200,000 Swiss Francs ($284,000 U.S.) per year between 1980 and 1985.)

  6. Floating Oil-Spill Containment Device

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    2012-01-01

    Previous oil containment booms have an open top that allows natural gas to escape, and have significant oil leakage due to wave action. Also, a subsea pyramid oil trap exists, but cannot move relative to moving oil plumes from deepsea oil leaks. The solution is to have large, moveable oil traps. One version floats on the sea surface and has a flexible tarp cover and a lower weighted skirt to completely entrap the floating oil and natural gas. The device must have at least three sides with boats pulling at each apex, and sonar or other system to track the slowly moving oil plume, so that the boats can properly locate the booms. The oil trap device must also have a means for removal of the oil and the natural gas. A second design version has a flexible pyramid cover that is attached by lines to ballast on the ocean floor. This is similar to fixed, metal pyramid oil capture devices in the Santa Barbara Channel off the coast of California. The ballast lines for the improved design, however, would have winches that can move the pyramid to always be located above the oil and gas plume. A third design is a combination of the first two. It uses a submerged pyramid to trap oil, but has no anchor and uses boats to locate the trap. It has ballast weights located along the bottom of the tarp and/or at the corners of the trap. The improved floating oil-spill containment device has a large floating boom and weighted skirt surrounding the oil and gas entrapment area. The device is triangular (or more than three sides) and has a flexible tarp cover with a raised gas vent area. Boats pull on the apex of the triangles to maintain tension and to allow the device to move to optimum locations to trap oil and gas. The gas is retrieved from a higher buoyant part of the tarp, and oil is retrieved from the floating oil layer contained in the device. These devices can be operated in relatively severe weather, since waves will break over the devices without causing oil leaking. Also, natural

  7. Floating point only SIMD instruction set architecture including compare, select, Boolean, and alignment operations

    DOEpatents

    Gschwind, Michael K.

    2011-03-01

    Mechanisms for implementing a floating point only single instruction multiple data instruction set architecture are provided. A processor is provided that comprises an issue unit, an execution unit coupled to the issue unit, and a vector register file coupled to the execution unit. The execution unit has logic that implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA). The floating point vector registers of the vector register file store both scalar and floating point values as vectors having a plurality of vector elements. The processor may be part of a data processing system.

  8. Apparatus for removing oil and other floating contaminants from a moving body of water

    DOEpatents

    Strohecker, J.W.

    1973-12-18

    The patent describes a process in which floating contaminants such as oil and solid debris are removed from a moving body of water by employing a skimming system which uses the natural gravitational flow of the water. A boom diagonally positioned across the body of water diverts the floating contaminants over a floating weir and into a retention pond where an underflow weir is used to return contaminant-free water to the moving body of water. The floating weir is ballasted to maintain the contaminant-receiving opening therein slightly below the surface of the water during fluctuations in the water level for skimming the contaminants with minimal water removal.

  9. Formulation and in-vitro evaluation of floating bilayer tablet of lisinopril maleate and metoprolol tartrate.

    PubMed

    Ijaz, Hira; Qureshi, Junaid; Danish, Zeeshan; Zaman, Muhammad; Abdel-Daim, Mohamed; Hanif, Muhammad; Waheed, Imran; Mohammad, Imran Shair

    2015-11-01

    The purpose of this study was to introduce the technology for the development of rate-controlled oral drug delivery system to overcome various physiological problems. Several approaches are being used for the purpose of increasing the gastric retentive time, including floating drug delivery system. Gastric floating lisinopril maleate and metoprolol tartrate bilayer tablets were formulated by direct compression method using the sodium starch glycolate, crosscarmellose sodium for IR layer. Eudragit L100, pectin, acacia as sustained release polymers in different ratios for SR metoprolol tartrate layer and sodium bicarbonate, citric acid as gas generating agents for the floating extended release layer. The floating bilayer tablets of lisinopril maleate and metoprolol tartrate were designed to overcome the various problems associated with conventional oral dosage form. Floating tablets were evaluated for floating lag time, drug contents and in-vitro dissolution profile and different kinetic release models were applied. It was clear that the different ratios of polymers affected the drug release and floating time. L2 and M4 showed good drug release profile and floating behavior. The linear regression and model fitting showed that all formulation followed Higuchi model of drug release model except M4 that followed zero order kinetic. From the study it is evident that a promising controlled release by floating bilyer tablets of lisinopril maleate and metoprolol tartrate can be developed successfully. PMID:26639495

  10. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  11. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  12. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  13. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 16 2013-07-01 2013-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  14. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  15. Evaporation mitigation by floating modular devices

    NASA Astrophysics Data System (ADS)

    Hassan, M. M.; Peirson, W. L.

    2016-05-01

    Prolonged periods of drought and consequent evaporation from open water bodies in arid parts of Australia continue to be a threat to water availability for agricultural production. Over many parts of Australia, the annual average evaporation exceeds the annual precipitation by more than 5 times. Given its significance, it is surprising that no evaporation mitigation technique has gained widespread adoption to date. High capital and maintenance costs of manufactured products are a significant barrier to implementation. The use of directly recycled clean plastic containers as floating modular devices to mitigate evaporation has been investigated for the first time. A six-month trial at an arid zone site in Australia of this potential cost effective solution has been undertaken. The experiment was performed using clean conventional drinking water bottles as floating modules on the open water surface of 240-L tanks with three varying degrees of covering (nil, 34% and 68%). A systematic reduction in evaporation is demonstrated during the whole study period that is approximately linearly proportional to the covered surface. These results provide a potential foundation for robust evaporation mitigation with the prospect of implementing a cost-optimal design.

  16. Flinking: Neither Floating nor Sinking.

    ERIC Educational Resources Information Center

    Wilson, Roger B.

    1993-01-01

    Describes an activity that challenges students to make an object that, when released under water, does not float up or sink down. The main concept this activity investigates is the density of ordinary objects in comparison to the density of water. (PR)

  17. Designing seaplane hulls and floats

    NASA Technical Reports Server (NTRS)

    Benoit,

    1926-01-01

    Experimental data, such as the results of tank tests of models, render it possible to predict, at least in principle, as to how a hull or float of a given shape will comport itself. We will see further along, however, how uncertain these methods are and how they leave room for empiricism, which will reign for a long time yet in seaplane research bureaus.

  18. Treatment of Aquaculture Wastewater Using Floating Vegetated Mats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods are needed for treating aquaculture wastewater. The goal is to improve wastewater quality sufficiently for it to be recycled to production ponds. One potential method for improving aquaculture wastewater is to use floating vegetation in treatment tanks. Alternatively, potential exists for ...

  19. Landau-level mixing, floating-up extended states, and scaling behavior in a GaAs-based two-dimensional electron system containing self-assembled InAs dots

    NASA Astrophysics Data System (ADS)

    Liang, Chi-Te; Liu, Chieh-Wen; Liu, Chieh-I.; Kim, Gil-Ho; Huang, C. F.; Hang, Da-Ren; Ritchie, D. A.

    Temperature-driven flow lines corresponding to Landau level filling factor ν = 2 ~ 4 were studied in the σxx -σxy plane in a GaAs-based two-dimensional electron system with self-assembled InAs dots. In the insulator-quantum Hall (I-QH) transition resulting from the floating-up extended states, the flow diagram showed the validity of the scaling and we observed the expected semicircle. On the other hand, the curve σxx (σxy) in the low-field insulator demonstrated the existence of Landau-level mixing. By decreasing the effective disorder, we found that such flow lines can leave the I-QH regime and follow the scaling for the plateau transition between ν = 4 and 2. The semicircle in the observed I-QH transition, in fact, originated from the distortion on the plateau-transition curve due to Landau-level mixing. Our study showed the importance of the level-mixing effects to the scaling and semicircle law as the extended states float up. We thank the MOST, Taiwan (Grant Number: MOST 104-2622-8-002 -003) for financial support.

  20. Research on stability of nozzle-floating plate institution

    NASA Astrophysics Data System (ADS)

    Huang, Bin; Tao, Jiayue; Yi, Jiajing; Chen, Shijing

    2016-01-01

    In this paper, air hammer instability of nozzle-floating plate institution in gas lubricated force sensor were studied. Through establishment of the theoretical model for the analysis of the nozzle-floating plate institution stability, combined with air hammer stability judgment theorems, we had some simulation research on the radius of the nozzle, the radius of the pressure chamber, pressure chamber depth, orifice radius and the relationship between air supply pressure and bearing capacity, in order to explore the instability mechanism of nozzle-floating plate institution. For conducting experimental observations for the stability of two groups nozzle-floating plate institution, which have typical structural parameters conducted experimental observations. We set up a special experimental device, verify the correctness of the theoretical study and simulation results. This paper shows that in the nozzle-floating plate institution, increasing the nozzle diameter, reduced pressure chamber radius, reducing the depth of the pressure chamber and increase the supply orifice radius, and other measures is conducive to system stability. Results of this study have important implications for research and design of gas lubricated force sensor.

  1. The Unified Floating Point Vector Coprocessor for Reconfigurable Hardware

    NASA Astrophysics Data System (ADS)

    Kathiara, Jainik

    There has been an increased interest recently in using embedded cores on FPGAs. Many of the applications that make use of these cores have floating point operations. Due to the complexity and expense of floating point hardware, these algorithms are usually converted to fixed point operations or implemented using floating-point emulation in software. As the technology advances, more and more homogeneous computational resources and fixed function embedded blocks are added to FPGAs and hence implementation of floating point hardware becomes a feasible option. In this research we have implemented a high performance, autonomous floating point vector Coprocessor (FPVC) that works independently within an embedded processor system. We have presented a unified approach to vector and scalar computation, using a single register file for both scalar operands and vector elements. The Hybrid vector/SIMD computational model of FPVC results in greater overall performance for most applications along with improved peak performance compared to other approaches. By parameterizing vector length and the number of vector lanes, we can design an application specific FPVC and take optimal advantage of the FPGA fabric. For this research we have also initiated designing a software library for various computational kernels, each of which adapts FPVC's configuration and provide maximal performance. The kernels implemented are from the area of linear algebra and include matrix multiplication and QR and Cholesky decomposition. We have demonstrated the operation of FPVC on a Xilinx Virtex 5 using the embedded PowerPC.

  2. Test Demonstration of Magnet Power Supply with Floating Capacitor Method

    NASA Astrophysics Data System (ADS)

    Shimogawa, Tetsushi; Morita, Yuichi; Sagawa, Ryu; Kurimoto, Yoshinori; Nakamura, Shu; Miura, Kazuki

    The Japan Proton Accelerator Research Complex (J-PARC) aims at achieving a MW-class proton accelerator facility. We plan to increase the beam power by shortening the repetition period of the Main Ring (MR) from the present period of 2.5 to 1 s in the future. In this scheme, there are serious concerns regarding the main magnets. One involves the increasing output voltage, and the other is related to the power variation of the electric system. We propose an innovative floating capacitor method to produce a high output voltage and suppress the power variation with capacitor energy storage for addressing these concerns. Nevertheless, the driving power supply used with this method needs to establish control of the floating capacitor voltage. We developed and introduced recovery control of the floating capacitor voltage for each accelerator cycle. We also confirmed that the tracking error can be corrected by iterative learning control with the floating capacitor method. In this article, the magnet power supply with the floating capacitor method is described, and test results achieved with the mini model power supply are presented.

  3. Robust Medical Isotope Production System

    SciTech Connect

    Klein, Steven Karl; Kimpland, Robert Herbert

    2015-06-15

    The success of this theoretical undertaking provided confidence that the behavior of new and evolving designs of fissile solution systems may be accurately estimated. Scaled up versions of SUPO, subcritical acceleratordriven systems, and other evolutionary designs have been examined.

  4. Ethanol production method and system

    DOEpatents

    Chen, M.J.; Rathke, J.W.

    1983-05-26

    Ethanol is selectively produced from the reaction of methanol with carbon monoxide and hydrogen in the presence of a transition metal carbonyl catalyst. Methanol serves as a solvent and may be accompanied by a less volatile co-solvent. The solution includes the transition metal carbonyl catalysts and a basic metal salt such as an alkali metal or alkaline earth metal formate, carbonate or bicarbonate. A gas containing a high carbon monoxide to hydrogen ratio, as is present in a typical gasifer product, is contacted with the solution for the preferential production of ethanol with minimal water as a byproduct. Fractionation of the reaction solution provides substantially pure ethanol product and allows return of the catalysts for reuse.

  5. Methanol production method and system

    DOEpatents

    Chen, Michael J.; Rathke, Jerome W.

    1984-01-01

    Ethanol is selectively produced from the reaction of methanol with carbon monoxide and hydrogen in the presence of a transition metal carbonyl catalyst. Methanol serves as a solvent and may be accompanied by a less volatile co-solvent. The solution includes the transition metal carbonyl catalysts and a basic metal salt such as an alkali metal or alkaline earth metal formate, carbonate or bicarbonate. A gas containing a high carbon monoxide to hydrogen ratio, as is present in a typical gasifer product, is contacted with the solution for the preferential production of ethanol with minimal water as a byproduct. Fractionation of the reaction solution provides substantially pure ethanol product and allows return of the catalysts for reuse.

  6. Evolvable Production Systems: Mechatronic Production Equipment with Evolutionary Control

    NASA Astrophysics Data System (ADS)

    Maffei, Antonio; Onori, Mauro; Neves, Pedro; Barata, José

    Current major roadmapping efforts have all clearly underlined that true industrial sustainability will require far higher levels of systems' autonomy and adaptability. In accordance with these recommendations, the Evolvable Production Systems (EPS) has aimed at developing such technological solutions and support mechanisms. Since its inception in 2002 as a next generation of production systems, the concept is being further developed and tested to emerge as a production system paradigm. Characteristically, Evolvable systems have distributed control, and are composed of intelligent modules with embedded control. A concerted effort is being exerted through European research projects in collaboration with manufacturers, technology/equipment suppliers, and universities. After introducing EPS, this paper presents current developments and applications.

  7. FloatBoost learning and statistical face detection.

    PubMed

    Li, Stan Z; Zhang, ZhenQiu

    2004-09-01

    A novel learning procedure, called FloatBoost, is proposed for learning a boosted classifier for achieving the minimum error rate. FloatBoost learning uses a backtrack mechanism after each iteration of AdaBoost learning to minimize the error rate directly, rather than minimizing an exponential function of the margin as in the traditional AdaBoost algorithms. A second contribution of the paper is a novel statistical model for learning best weak classifiers using a stagewise approximation of the posterior probability. These novel techniques lead to a classifier which requires fewer weak classifiers than AdaBoost yet achieves lower error rates in both training and testing, as demonstrated by extensive experiments. Applied to face detection, the FloatBoost learning method, together with a proposed detector pyramid architecture, leads to the first real-time multiview face detection system reported. PMID:15742888

  8. Research of design challenges and new technologies for floating LNG

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Hyun; Ha, Mun-Keun; Kim, Soo-Young; Shin, Sung-Chul

    2014-06-01

    With the rate of worldwide LNG demand expected to grow faster than that of gas demand, most major oil companies are currently investing their resources to develop floating LNG-FLNG (i.e. LNG FSRU and LNG FPSO). The global Floating LNG (FLNG) market trend will be reviewed based on demand and supply chain relationships. Typical technical issues associated with FLNG design are categorized in terms of global performance evaluation. Although many proven technologies developed through LNG carrier and oil FPSO projects are available for FLNG design, we are still faced with several technical challenges to clear for successful FLNG projects. In this study, some of the challenges encountered during development of the floating LNG facility (i.e. LNG FPSO and FSRU) will be reviewed together with their investigated solution. At the same time, research of new LNG-related technologies such as combined containment system will be presented.

  9. Floating cultivation of marine cyanobacteria using coal fly ash.

    PubMed

    Matsumoto, M; Yoshida, E; Takeyama, H; Matsunaga, T

    2000-01-01

    The aim of this study was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. We have investigated the viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine micro-algae. The marine cyanobacterium Synechococcus sp. NKBG 040607 was found to adhere to floating CFA blocks in liquid culture medium. Maximum density of attached cells of 2.0 x 10(8) cells/cm2 was achieved using seawater. The marine cyanobacterium Synechococcus sp. NKBG 042902 weakly adhered to floating CFA blocks in BG-11 medium. Increasing the concentration of calcium ion in the culture medium enhanced adherence to CFA blocks. PMID:10849778

  10. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    Dr. M.A. Ebadian

    2000-01-13

    The purpose of the project is to increase the productivity and economics of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCB's and lead-base paint and provides worker and environmental protection by continuously recycling the blast media and the full containment of the dust generated in the process.