WorldWideScience

Sample records for bio-optical profiling floats

  1. Bio-optical profiling floats as new observational tools for biogeochemical and ecosystem studies: Potential synergies with ocean color remote sensing

    Energy Technology Data Exchange (ETDEWEB)

    Claustre, H.; Bishop, J.; Boss, E.; Bernard, S.; Berthon, J.-F.; Coatanoan, C.; Johnson, K.; Lotiker, A.; Ulloa, O.; Perry, M.J.; D' Ortenzio, F.; D' andon, O.H.F.; Uitz, J.

    2009-10-01

    Profiling floats now represent a mature technology. In parallel with their emergence, the field of miniature, low power bio-optical and biogeochemical sensors is rapidly evolving. Over recent years, the bio-geochemical and bio-optical community has begun to benefit from the increase in observational capacities by developing profiling floats that allow the measurement of key biooptical variables and subsequent products of biogeochemical and ecosystem relevance like Chlorophyll a (Chla), optical backscattering or attenuation coefficients which are proxies of Particulate Organic Carbon (POC), Colored Dissolved Organic Matter (CDOM). Thanks to recent algorithmic improvements, new bio-optical variables such as backscattering coefficient or absorption by CDOM, at present can also be extracted from space observations of ocean color. In the future, an intensification of in situ measurements by bio-optical profiling floats would permit the elaboration of unique 3D/4D bio-optical climatologies, linking surface (remotely detected) properties to their vertical distribution (measured by autonomous platforms), with which key questions in the role of the ocean in climate could be addressed. In this context, the objective of the IOCCG (International Ocean Color Coordinating Group) BIO-Argo working group is to elaborate recommendations in view of a future use of bio-optical profiling floats as part of a network that would include a global array that could be 'Argo-relevant', and specific arrays that would have more focused objectives or regional targets. The overall network, realizing true multi-scale sustained observations of global marine biogeochemistry and biooptics, should satisfy the requirements for validation of ocean color remote sensing as well as the needs of a wider community investigating the impact of global change on biogeochemical cycles and ecosystems. Regarding the global profiling float array, the recommendation is that Chla as well as POC should be the

  2. Temporal variability of chlorophyll distribution in the Gulf of Mexico: bio-optical data from profiling floats

    Directory of Open Access Journals (Sweden)

    O. Pasqueron de Fommervault

    2017-12-01

    Full Text Available Chlorophyll concentration is a key oceanic biogeochemical variable. In the Gulf of Mexico (GOM, its distribution, which is mainly obtained from satellite surface observations and scarce in situ experiments, is still poorly understood. In 2011–2012, eight profiling floats equipped with biogeochemical sensors were deployed for the first time in the GOM and generated an unprecedented dataset that significantly increased the number of chlorophyll vertical distribution measurements in the region. The analysis of these data, once calibrated, permits us to reconsider the spatial and temporal variability of the chlorophyll concentration in the water column. At a seasonal scale, results confirm the surface signal seen by satellites, presenting maximum concentrations in winter and low values in summer. It is shown that the deepening of the mixed layer is the primary factor triggering the chlorophyll surface increase in winter. In the GOM, a possible interpretation is that this surface increase corresponds to a biomass increase. However, the present dataset suggests that the basin-scale climatological surface increase in chlorophyll content results from a vertical redistribution of subsurface chlorophyll and/or photoacclimation processes, rather than a net increase of biomass. One plausible explanation for this is the decoupling between the mixed-layer depth and the deep nutrient reservoir since mixed-layer depth only reaches the nitracline in sporadic events in the observations. Float measurements also provide evidence that the depth and the magnitude of the deep chlorophyll maximum is strongly controlled by the mesoscale variability, with higher chlorophyll biomass generally observed in cyclones rather than anticyclones.

  3. Temporal variability of chlorophyll distribution in the Gulf of Mexico: bio-optical data from profiling floats

    Science.gov (United States)

    Pasqueron de Fommervault, Orens; Perez-Brunius, Paula; Damien, Pierre; Camacho-Ibar, Victor F.; Sheinbaum, Julio

    2017-12-01

    Chlorophyll concentration is a key oceanic biogeochemical variable. In the Gulf of Mexico (GOM), its distribution, which is mainly obtained from satellite surface observations and scarce in situ experiments, is still poorly understood. In 2011-2012, eight profiling floats equipped with biogeochemical sensors were deployed for the first time in the GOM and generated an unprecedented dataset that significantly increased the number of chlorophyll vertical distribution measurements in the region. The analysis of these data, once calibrated, permits us to reconsider the spatial and temporal variability of the chlorophyll concentration in the water column. At a seasonal scale, results confirm the surface signal seen by satellites, presenting maximum concentrations in winter and low values in summer. It is shown that the deepening of the mixed layer is the primary factor triggering the chlorophyll surface increase in winter. In the GOM, a possible interpretation is that this surface increase corresponds to a biomass increase. However, the present dataset suggests that the basin-scale climatological surface increase in chlorophyll content results from a vertical redistribution of subsurface chlorophyll and/or photoacclimation processes, rather than a net increase of biomass. One plausible explanation for this is the decoupling between the mixed-layer depth and the deep nutrient reservoir since mixed-layer depth only reaches the nitracline in sporadic events in the observations. Float measurements also provide evidence that the depth and the magnitude of the deep chlorophyll maximum is strongly controlled by the mesoscale variability, with higher chlorophyll biomass generally observed in cyclones rather than anticyclones.

  4. Bio-Optical sensors on Argo Floats. Reports of the international ocean-colour coordinating group

    CSIR Research Space (South Africa)

    Bernard, S

    2011-01-01

    Full Text Available Institute, USA Aneesh Lotliker INCOIS, India Osvaldo Ulloa Universidad de Concepción, Chile Series Editor: Venetia Stuart Correct citation for this publication: IOCCG (2011). Bio-Optical Sensors on Argo Floats. Claustre, H. (ed.), Reports...

  5. Two databases derived from BGC-Argo float measurements for marine biogeochemical and bio-optical applications

    Directory of Open Access Journals (Sweden)

    E. Organelli

    2017-11-01

    Full Text Available Since 2012, an array of 105 Biogeochemical-Argo (BGC-Argo floats has been deployed across the world's oceans to assist in filling observational gaps that are required for characterizing open-ocean environments. Profiles of biogeochemical (chlorophyll and dissolved organic matter and optical (single-wavelength particulate optical backscattering, downward irradiance at three wavelengths, and photosynthetically available radiation variables are collected in the upper 1000 m every 1 to 10 days. The database of 9837 vertical profiles collected up to January 2016 is presented and its spatial and temporal coverage is discussed. Each variable is quality controlled with specifically developed procedures and its time series is quality-assessed to identify issues related to biofouling and/or instrument drift. A second database of 5748 profile-derived products within the first optical depth (i.e., the layer of interest for satellite remote sensing is also presented and its spatiotemporal distribution discussed. This database, devoted to field and remote ocean color applications, includes diffuse attenuation coefficients for downward irradiance at three narrow wavebands and one broad waveband (photosynthetically available radiation, calibrated chlorophyll and fluorescent dissolved organic matter concentrations, and single-wavelength particulate optical backscattering. To demonstrate the applicability of these databases, data within the first optical depth are compared with previously established bio-optical models and used to validate remotely derived bio-optical products. The quality-controlled databases are publicly available from the SEANOE (SEA scieNtific Open data Edition publisher at https://doi.org/10.17882/49388 and https://doi.org/10.17882/47142 for vertical profiles and products within the first optical depth, respectively.

  6. Two databases derived from BGC-Argo float measurements for marine biogeochemical and bio-optical applications

    Science.gov (United States)

    Organelli, Emanuele; Barbieux, Marie; Claustre, Hervé; Schmechtig, Catherine; Poteau, Antoine; Bricaud, Annick; Boss, Emmanuel; Briggs, Nathan; Dall'Olmo, Giorgio; D'Ortenzio, Fabrizio; Leymarie, Edouard; Mangin, Antoine; Obolensky, Grigor; Penkerc'h, Christophe; Prieur, Louis; Roesler, Collin; Serra, Romain; Uitz, Julia; Xing, Xiaogang

    2017-11-01

    Since 2012, an array of 105 Biogeochemical-Argo (BGC-Argo) floats has been deployed across the world's oceans to assist in filling observational gaps that are required for characterizing open-ocean environments. Profiles of biogeochemical (chlorophyll and dissolved organic matter) and optical (single-wavelength particulate optical backscattering, downward irradiance at three wavelengths, and photosynthetically available radiation) variables are collected in the upper 1000 m every 1 to 10 days. The database of 9837 vertical profiles collected up to January 2016 is presented and its spatial and temporal coverage is discussed. Each variable is quality controlled with specifically developed procedures and its time series is quality-assessed to identify issues related to biofouling and/or instrument drift. A second database of 5748 profile-derived products within the first optical depth (i.e., the layer of interest for satellite remote sensing) is also presented and its spatiotemporal distribution discussed. This database, devoted to field and remote ocean color applications, includes diffuse attenuation coefficients for downward irradiance at three narrow wavebands and one broad waveband (photosynthetically available radiation), calibrated chlorophyll and fluorescent dissolved organic matter concentrations, and single-wavelength particulate optical backscattering. To demonstrate the applicability of these databases, data within the first optical depth are compared with previously established bio-optical models and used to validate remotely derived bio-optical products. The quality-controlled databases are publicly available from the SEANOE (SEA scieNtific Open data Edition) publisher at https://doi.org/10.17882/49388" target="_blank">https://doi.org/10.17882/49388 and https://doi.org/10.17882/47142" target="_blank">https://doi.org/10.17882/47142 for vertical profiles and products within the first optical depth, respectively.

  7. Biogeochemical sensor performance in the SOCCOM profiling float array

    Science.gov (United States)

    Johnson, Kenneth S.; Plant, Joshua N.; Coletti, Luke J.; Jannasch, Hans W.; Sakamoto, Carole M.; Riser, Stephen C.; Swift, Dana D.; Williams, Nancy L.; Boss, Emmanuel; Haëntjens, Nils; Talley, Lynne D.; Sarmiento, Jorge L.

    2017-08-01

    The Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) program has begun deploying a large array of biogeochemical sensors on profiling floats in the Southern Ocean. As of February 2016, 86 floats have been deployed. Here the focus is on 56 floats with quality-controlled and adjusted data that have been in the water at least 6 months. The floats carry oxygen, nitrate, pH, chlorophyll fluorescence, and optical backscatter sensors. The raw data generated by these sensors can suffer from inaccurate initial calibrations and from sensor drift over time. Procedures to correct the data are defined. The initial accuracy of the adjusted concentrations is assessed by comparing the corrected data to laboratory measurements made on samples collected by a hydrographic cast with a rosette sampler at the float deployment station. The long-term accuracy of the corrected data is compared to the GLODAPv2 data set whenever a float made a profile within 20 km of a GLODAPv2 station. Based on these assessments, the fleet average oxygen data are accurate to 1 ± 1%, nitrate to within 0.5 ± 0.5 µmol kg-1, and pH to 0.005 ± 0.007, where the error limit is 1 standard deviation of the fleet data. The bio-optical measurements of chlorophyll fluorescence and optical backscatter are used to estimate chlorophyll a and particulate organic carbon concentration. The particulate organic carbon concentrations inferred from optical backscatter appear accurate to with 35 mg C m-3 or 20%, whichever is larger. Factors affecting the accuracy of the estimated chlorophyll a concentrations are evaluated.Plain Language SummaryThe ocean science community must move toward greater use of autonomous platforms and sensors if we are to extend our knowledge of the effects of climate driven change within the ocean. Essential to this shift in observing strategies is an understanding of the performance that can be obtained from biogeochemical sensors on platforms deployed for years and the

  8. Merging Ocean Color and physical Argo data to extend bio-optical properties to depth using neural networks: A global 3D view of phytoplankton biomass and phytoplankton communities composition

    Science.gov (United States)

    Sauzède, R.; Claustre, H.; Jamet, C.; Uitz, J.; Dall'Olmo, G.; D'Ortenzio, F.; Gentili, B.; Poteau, A.; Schmechtig, C.

    2016-02-01

    Ocean color observations enable the estimation of bio-optical proxies of phytoplankton biomass (e.g. chlorophyll a concentration, Chla, and particulate backscattering coefficient, bbp) in the surface layer of the ocean quasi-synoptically. In parallel, the Argo program distributes vertical profiles of the ocean physical properties with a global coverage and a high spatio-temporal resolution (every 10 days for 3°x3° area). Because physical properties influence the vertical distribution of phytoplankton biomass, merging satellite and Argo data bear strong potential to infer the vertical distribution of bio-optical properties at global scale with high space-time resolution. Two neural network-based methods (SOCA for merged Satellite Ocean Color and Argo data) are developed: one to infer the vertical distribution of Chla and phytoplankton community size indices (PCSI); the second for bbp. SOCA is trained and validated using a database of 5000 concurrent vertical profiles of temperature, salinity, and bio-optical properties collected by Bio-Argo floats, matched up with satellite bio-optical products. In practice, SOCA requires as input only the vertically resolved physical properties and concomitant satellite products to extend the surface bio-optical properties to depth. Evaluated against 20% of our database, SOCA-retrieved bio-optical profiles are very consistent with measured in situ profiles (error within 40-55% for Chla and PCSI and of 18% for bbp). Additional validation based on fully independent data acquired during oceanographic cruises shows again very satisfactory results. The data used for training the neural networks are representative of the global ocean in terms of trophic and oceanographic conditions, making SOCA applicable to most open-ocean waters. Finally, global and regional 3D views of Chla, PCSI and bbp obtained from SOCA represent a new important tool to assess seasonal and interannual variability in phytoplankton biomass and community composition.

  9. Bio-optical profiling floats as new observational tools for biogeochemical and ecosystem studies: Potential synergies with ocean color remote sensing

    CSIR Research Space (South Africa)

    Claustre, H

    2009-09-01

    Full Text Available de Oceanograf?a, Laboratorio de Procesos Oceanogr?ficos y Clima (PROFC), Universidad de Concepci?n, Cabina 7 - Barrio Universitario, Casilla 160-C, Concepci?n 3, Chile, Email: oulloa@profc.udec.cl (10) University of Maine, School of Marine Science...

  10. A statistical method for correcting salinity observations from autonomous profiling floats: An ARGO perspective

    Digital Repository Service at National Institute of Oceanography (India)

    Durand, F.; Reverdin, G.

    The Profiling Autonomous Lagrangian Circulation Explorer (PALACE) float is used to implement the Array for Real-Time Geostrophic Oceanography (ARGO). This study presents a statistical approach to correct salinity measurement errors of an ARGO...

  11. Long-Term Observations of Ocean Biogeochemistry with Nitrate and Oxygen Sensors in Apex Profiling Floats

    Science.gov (United States)

    Johnson, K. S.; Coletti, L.; Jannasch, H.; Martz, T.; Swift, D.; Riser, S.

    2008-12-01

    Long-term, autonomous observations of ocean biogeochemical cycles are now feasible with chemical sensors in profiling floats. These sensors will enable decadal-scale observations of trends in global ocean biogeochemical cycles. Here, we focus on measurements on nitrate and dissolved oxygen. The ISUS (In Situ Ultraviolet Spectrophotometer) optical nitrate sensor has been adapted to operate in a Webb Research, Apex profiling float. The Apex float is of the type used in the Argo array and is designed for multi-year, expendable deployments in the ocean. Floats park at 1000 m depth and make 60 nitrate and oxygen measurements at depth intervals ranging from 50 m below 400 m to 5 m in the upper 100 m as they profile to the surface. All data are transmitted to shore using the Iridium telemetry system and they are available on the Internet in near-real time. Floats equipped with ISUS and an Aanderaa oxygen sensor are capable of making 280 vertical profiles from 1000 m. At a 5 day cycle time, the floats should have nearly a four year endurance. Three floats have now been deployed at the Hawaii Ocean Time series station (HOT), Ocean Station Papa (OSP) in the Gulf of Alaska and at 50 South, 30 East in the Southern Ocean. Two additional floats are designated for deployment at the Bermuda Atlantic Time Series station (BATS) and in the Drake Passage. The HOT float has made 56 profiles over 260 days and should continue operating for 3 more years. Nitrate concentrations are in excellent agreement with the long-term mean observed at HOT. No significant long-term drift in sensor response has occurred. A variety of features have been observed in the HOT nitrate data that are linked to contemporaneous changes in oxygen production and mesoscale dynamics. The impacts of these features will be briefly described. The Southern Ocean float has operated for 200 days and is now observing reinjection of nitrate into surface waters as winter mixing occurs(surface nitrate > 24 micromolar). We

  12. Annual nitrate drawdown observed by SOCCOM profiling floats and the relationship to annual net community production

    Science.gov (United States)

    Johnson, Kenneth S.; Plant, Joshua N.; Dunne, John P.; Talley, Lynne D.; Sarmiento, Jorge L.

    2017-08-01

    Annual nitrate cycles have been measured throughout the pelagic waters of the Southern Ocean, including regions with seasonal ice cover and southern hemisphere subtropical zones. Vertically resolved nitrate measurements were made using in situ ultraviolet spectrophotometer (ISUS) and submersible ultraviolet nitrate analyzer (SUNA) optical nitrate sensors deployed on profiling floats. Thirty-one floats returned 40 complete annual cycles. The mean nitrate profile from the month with the highest winter nitrate minus the mean profile from the month with the lowest nitrate yields the annual nitrate drawdown. This quantity was integrated to 200 m depth and converted to carbon using the Redfield ratio to estimate annual net community production (ANCP) throughout the Southern Ocean south of 30°S. A well-defined, zonal mean distribution is found with highest values (3-4 mol C m-2 yr-1) from 40 to 50°S. Lowest values are found in the subtropics and in the seasonal ice zone. The area weighted mean was 2.9 mol C m-2 yr-1 for all regions south of 40°S. Cumulative ANCP south of 50°S is 1.3 Pg C yr-1. This represents about 13% of global ANCP in about 14% of the global ocean area.Plain Language SummaryThis manuscript reports on 40 annual cycles of nitrate observed by chemical sensors on SOCCOM profiling floats. The annual drawdown in nitrate concentration by phytoplankton is used to assess the spatial variability of annual net community production in the Southern Ocean. This ANCP is a key component of the global carbon cycle and it exerts an important control on atmospheric carbon dioxide. We show that the results are consistent with our prior understanding of Southern Ocean ANCP, which has required decades of observations to accumulate. The profiling floats now enable annual resolution of this key process. The results also highlight spatial variability in ANCP in the Southern Ocean.

  13. Seven hundred years of peat formation recorded throughout a deep floating mire profile from Central Italy

    Science.gov (United States)

    Lobianco, Daniela; D'Orazio, Valeria; Miano, Teodoro; Zaccone, Claudio

    2016-04-01

    ), an ash content ranging from 0.8 and 7.4%, an average gravimetric water content of 26.6±7.7 gwater gdrypeat-1, and a pH generally increasing with depth (from 4.1 to 7.2). The C content along the profile ranged between 35 and 47% (avg., 41±4%), whereas the N between 0.3 and 1.1% (avg., 0.5±0.1%). Main atomic ratios (C/N, H/C and O/C) and FT-IR spectra seem to confirm what found during the visual inspection of the core, i.e., Sphagnum material so well preserved that it is hard to classify it as "peat". In fact, the 14C age dating suggests that the first 110 cm of Sphagnum material accumulated in ca. 55 yrs, thus resulting in an average growing rate of 2 cm yr-1. The remaining 300 cm (from 100 to 400 cm of depth), i.e., the submerged part of the island, consist of peat showing completely different botanical composition (reed-fen peat and silty peat rich in reeds) and physical and chemical properties. In particular, both bulk density (avg., 0.09±0.05 g cm-3) and ash content increase, reaching their maximum at 300-325 cm of depth (0.27 g cm-3 and 17%, respectively), whereas the average gravimetric water content significantly decreases (17.4±9.0 gwater gdrypeat-1). The pH ranges from 6.6 and 7.4. Both C and N along this section of the profile show higher average contents (44±3 and 1.3±0.6%, respectively) compared to those recorded in the upper 100 cm layer; furthermore, the decrease with depth of C/N, H/C and O/C atomic ratios, as well as main absorption bands of FT-IR spectra, clearly indicate the occurrence of an organic matter highly humified. The estimated accumulation rate for the bottom 300 cm of the island is 0.5 cm yr-1. At the best of our knowledge, this work represents the first characterization of a (4 m) deep floating mire profile. At Posta Fibreno, the deep water layer below the base of the island (7 m) and the movement on the water surface probably avoided the transition from floating island to firm land, thus allowing this island to float during the

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

    Science.gov (United States)

    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.

  15. Quality of temperature and salinity data from Argo profiling floats in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Parvathi, V.; Pankajakshan, T.; Rajkumar, M.; Prasannakumar, S.; Muraleedharan, P.M.; Ravichandran, M.; Rao, R.R.; Gopalakrishna, V.V.

    In the present study, temperature and salinity from APEX -Argo floats with reported SPB (Argo-SPB) and salinity from normal floats without any reported SPB (Argo-N) in the BoB have been subjected to quality check (QC) Method used for QC depends...

  16. Observing the seasonal cycle of the upper ocean in the Ross Sea, Antarctica, with autonomous profiling floats

    Science.gov (United States)

    Porter, D. F.; Springer, S. R.; Padman, L.; Fricker, H. A.; Bell, R. E.

    2017-12-01

    The upper layers of the Southern Ocean where it meets the Antarctic ice sheet undergoes a large seasonal cycle controlled by surface radiation and by freshwater fluxes, both of which are strongly influenced by sea ice. In regions where seasonal sea ice and icebergs limit use of ice-tethered profilers and conventional moorings, autonomous profiling floats can sample the upper ocean. The deployment of seven Apex floats (by sea) and six ALAMO floats (by air) provides unique upper ocean hydrographic data in the Ross Sea close to the Ross Ice Shelf front. A novel choice of mission parameters - setting parking depth deeper than the seabed - limits their drift, allowing us to deploy the floats close to the ice shelf front, while sea ice avoidance algorithms allow the floats to to sample through winter under sea ice. Hydrographic profiles show the detailed development of the seasonal mixed layer close to the Ross front, and interannual variability of the seasonal mixed layer and deeper water masses on the central Ross Sea continental shelf. After the sea ice breakup in spring, a warm and fresh surface mixed layer develops, further warming and deepening throughout the summer. The mixed layer deepens, with maximum temperatures exceeding 0ºC in mid-February. By March, the surface energy budget becomes negative and sea ice begins to form, creating a cold, saline and dense surface layer. Once these processes overcome the stable summer stratification, convection erodes the surface mixed layer, mixing some heat downwards to deeper layers. There is considerable interannual variability in the evolution and strength of the surface mixed layer: summers with shorter ice-free periods result in a cooler and shallower surface mixed layer, which accumulates less heat than the summers with longer ice-free periods. Early ice breakup occurred in all floats in 2016/17 summer, enhancing the absorbed solar flux leading to a warmer surface mixed layer. Together, these unique measurements from

  17. Small-Scale Bio-Optical Distributions in the Upper Ocean (AASERT)

    National Research Council Canada - National Science Library

    Cowles, Timothy

    2000-01-01

    This ASSERT project supported a graduate student, Ms. Lisa Eisner, to apply newly-developed, state-of-the-art bio-optical instrumentation to the analysis of phytoplankton processes in biological oceanography. Ms...

  18. Temperature, salinity and dissolved oxygen profile data from globally distributed Argo profiling floats through the month of August 2017 for the Global Argo Data Repository, 1995-09-07 to 2017-08-31 (NCEI Accession 0042682)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent all data collected from Argo profiling floats through the current month (August 2017). The NOAA National Centers for Environmental Information...

  19. Upper Ocean Measurements from Profiling Floats in the Arabian Sea During NASCar

    Science.gov (United States)

    2015-09-30

    top-level goals] OBJECTIVES The work proposed here is designed to examine the seasonal evolution of the upper ocean in the northern Arabian...circulation of the Arabian Sea and the seasonal and spatial evolution of the surface mixed layer, and would be used in conjunction with HYCOM model...available in real-time on the internet , as is generally done with Argo-type float data. We have collaborated for many years with colleagues in India

  20. Ecological and morphological profile of floating spherical Cladophora socialis aggregations in central Thailand.

    Directory of Open Access Journals (Sweden)

    Isao Tsutsui

    Full Text Available The unique beauty of spherical aggregation forming algae has attracted much attention from both the scientific and lay communities. Several aegagropilous seaweeds have been identified to date, including the plants of genus Cladophora and Chaetomorpha. However, this phenomenon remains poorly understood. In July 2013, a mass occurrence of spherical Cladophora aggregations was observed in a salt field reservoir in Central Thailand. The aims of the present study were to describe the habitat of the spherical aggregations and confirm the species. We performed a field survey, internal and external morphological observations, pyrenoid ultrastructure observations, and molecular sequence analysis. Floating spherical Cladophora aggregations (1-8 cm in diameter were observed in an area ~560 m2, on the downwind side of the reservoir where there was water movement. Individual filaments in the aggregations were entangled in each other; consequently, branches growing in different directions were observed within a clump. We suggest that water movement and morphological characteristics promote the formation of spherical aggregations in this species. The molecular sequencing results revealed that the study species was highly homologous to both C. socialis and C. coelothrix. However, the diameter of the apical cells in the study species was less than that of C. coelothrix. The pyrenoid ultrastructure was more consistent with that of C. socialis. We conclude that the study species is C. socialis. This first record of spherical aggregations in this species advances our understanding of these formations. However, further detailed physical measurements are required to fully elucidate the mechanism behind these spherical formations.

  1. BIO-OPTICAL CHARACTERIZATION OF THE DINOFLAGELLATE GYMNODINIUM BREVE AND THE DIATOM THALASSIOSIRA WEISSFLOGII IN OUTDOOR TANKS

    Science.gov (United States)

    The bio-optical signatures of harmful algal blooms can be used to define ocean color satellite algorithms. We characterized the bio-optical properties of nutrient-replete cultures of the red tide dinoflagellate Gymnodinium breve and the diatom Thalassiosira weissflogii. We cultur...

  2. HYDRODYNAMICS AND BIO-OPTICAL ASSESSMENT OF TWO PRISTINE SUBTROPICAL ESTUARIES IN SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Mauricio Almeida Noernberg

    2014-12-01

    Full Text Available Measuring small-scale physical processes and how they affect the spatial patterns of sea water's optical constituents plays a key role in understanding the functioning of complex coastal ecosystems such as estuaries. The spatial variations of physical and bio-optical water properties were investigated during one spring tidal cycle in austral summer, on two transects across the channel of the Medeiros and Itaqui sub-estuaries. These sub-estuaries are a biosphere reserve, and part of the Paranaguá Estuarine System, located on the Southern Brazilian coast. Both sub-estuaries were classified as Type 1a, wellmixed with low stratification. The salinity variations are in phase with the water level, and the tidal propagation is well represented by a standing wave. The vertical velocity profiles showed little vertical shear, and the intensity of the u-component of the velocity varied semi-diurnally. The upper estuary salt transport was dominated by tidal diffusion in an unstable water column. The optical environment presented a mixed dominance of optically active substances, as indicated by the absorption coefficients of dissolved and particulate matter. The colored dissolved organic matter (CDOM showed overall conservative behavior and was dominant in light absorption below 550 nm in the Medeiros, while nonalgal particles play the most important role in light absorption in the Itaqui in the blue absorption band. The phytoplanktonic contribution is prominent in the red domain and increases as a function of saline intrusion. However, due to the influence of freshwater discharge and the re-suspension of bottom sediments induced by physical processes, the concentrations of the optical components in the water column do not generally have any simple relationships between them.

  3. Bio-Optical Characteristics of the Northern Gulf of California during June 2008

    Directory of Open Access Journals (Sweden)

    Martha Bastidas-Salamanca

    2014-01-01

    Full Text Available Bio-optical variables in the Northern Gulf of California were analyzed using in situ and satellite data obtained during a cruise in June 2008. The study area was divided into three bio-optical regions: Upper Gulf (UG, Northern Gulf (NG, and Great Isles (GI. Each region was characterized according to phytoplankton pigment concentration, phytoplankton and nonpigmented material spectral absorption coefficients, and spectral reflectance. Observed patterns were an indication of the shift in bio-optical conditions from north to south going from turbid and eutrophic waters to mesotrophic ones. Although there was a good agreement between satellite and in situ Chla (RMSE ±33%, an overestimation of in situ Chla was observed. This was partly explained by the presence of nonalgal particles, as well as the influence of desert and continental aerosols, which is generally overcorrected in the standard processing. The UG and NG could be considered as Case  2 waters, but they did exhibit different bio-optical characteristics. This implies that both biological and optical properties should be invoked to better understand water reflectance variability in the study region and its implications for the remote sensing of Chla and biogeochemical processes.

  4. Bio-optical water quality dynamics observed from MERIS in Pensacola Bay, Florida

    Science.gov (United States)

    Observed bio-optical water quality data collected from 2009 to 2011 in Pensacola Bay, Florida were used to develop empirical remote sensing retrieval algorithms for chlorophyll a (Chla), colored dissolved organic matter (CDOM), and suspended particulate matter (SPM). Time-series ...

  5. Feature Issue Introduction: Bio-Optics in Clinical Applications, Nanotechnology, and Drug Discovery

    OpenAIRE

    Nordstrom, Robert J.; Almutairi, Adah; Hillman, Elizabeth M.C.

    2010-01-01

    The editors introduce the Biomedical Optics Express feature issue, “Bio-Optics in Clinical Applications, Nanotechnology, and Drug Discovery,” which combines three technical areas from the 2010 Optical Society of America (OSA), Biomedical Optics (BIOMED) Topical Meeting held on 11–14 April in Miami, FL and includes contributions from conference attendees.

  6. Primary production calculations for sea ice from bio-optical observations in the Baltic Sea

    Directory of Open Access Journals (Sweden)

    Susann Müller

    2016-09-01

    Full Text Available Abstract Bio-optics is a powerful approach for estimating photosynthesis rates, but has seldom been applied to sea ice, where measuring photosynthesis is a challenge. We measured absorption coefficients of chromophoric dissolved organic matter (CDOM, algae, and non-algal particles along with solar radiation, albedo and transmittance at four sea-ice stations in the Gulf of Finland, Baltic Sea. This unique compilation of optical and biological data for Baltic Sea ice was used to build a radiative transfer model describing the light field and the light absorption by algae in 1-cm increments. The maximum quantum yields and photoadaptation of photosynthesis were determined from 14C-incorporation in photosynthetic-irradiance experiments using melted ice. The quantum yields were applied to the radiative transfer model estimating the rate of photosynthesis based on incident solar irradiance measured at 1-min intervals. The calculated depth-integrated mean primary production was 5 mg C m–2 d–1 for the surface layer (0–20 cm ice depth at Station 3 (fast ice and 0.5 mg C m–2 d–1 for the bottom layer (20–57 cm ice depth. Additional calculations were performed for typical sea ice in the area in March using all ice types and a typical light spectrum, resulting in depth-integrated mean primary production rates of 34 and 5.6 mg C m–2 d–1 in surface ice and bottom ice, respectively. These calculated rates were compared to rates determined from 14C incorporation experiments with melted ice incubated in situ. The rate of the calculated photosynthesis and the rates measured in situ at Station 3 were lower than those calculated by the bio-optical algorithm for typical conditions in March in the Gulf of Finland by the bio-optical algorithm. Nevertheless, our study shows the applicability of bio-optics for estimating the photosynthesis of sea-ice algae.

  7. On the Relationship Between Satellite-Estimated Bio-Optical and Thermal Properties in the Gulf of Mexico

    National Research Council Canada - National Science Library

    Jolliff, Jason K; Kindle, John C; Penta, Bradley; Helber, Robert; Lee, Zhongping; Shulman, Igor G; Amone, Robert A; Rowley, Clark D

    2008-01-01

    .... Navy's Modular Ocean Data Assimilation System (MODAS) in order to examine the interdependencies between bio-optical fields and their relationship to seasonal and mesoscale changes in upper ocean thermal structure...

  8. FLOAT Project

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.; Aarup, Bendt

    The objective of the FLOAT project is to study the reliability of high-performance fibre-reinforced concrete, also known as Compact Reinforced Composite (CRC), for the floats of wave energy converters. In order to reach a commercial breakthrough, wave energy converters need to achieve a lower price...

  9. Impact of Bio-optical Data Assimilation on Short-term Coupled Physical, Bio-optical Model Predictions

    Science.gov (United States)

    2013-04-30

    profiles show agreement to generally be within 0.1 °C and 0.01 psu. [9] Four NRL and two Rutgers University SLOCUM gliders [Schofield et al., 2007... Slocum gliders : Robust and ready,,/. Field Rob., 24(d), 473-485. Shulman, I., B. Pcnta. M. A. Molinc, S. H. D. Haddock, S. Anderson, M. Oliver, and...RA’ ft. SL’R •N-^4r^-_^-- STATIONS * #*-^ÜV\\ M2* * ~*^jL / * */» \\ * I — GLIDERS

  10. Temperature profile and other data collected using current meter, profiling floats, and drifting buoy from the Atlantic Ocean as part of the IDOE/POLYMODE (International Decade of Ocean Exploration / combination of USSR POLYGON project and US MODE) from 18 July 1977 to 18 October 1979 (NODC Accession 8100508)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, pressure, and other data were collected using current meter, profiling floats, and drifting buoy in the Atlantic Ocean from July 18, 1977 to October 18,...

  11. SeaBASS Bio-optical and pigment data collected from 1979-08-22 to 2011-12-14 (NCEI Accession 0086308)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains SeaWiFS Bio-optical Archive and Storage System (SeaBASS) bio-optical, pigment, and other data collected from 1979-08-22 to 2011-12-14....

  12. Optimizing the bio-optical algorithm for estimating chlorophyll-a and phycocyanin concentrations in inland waters in Korea

    Science.gov (United States)

    Several bio-optical algorithms were developed to estimate the chlorophyll-a (Chl-a) and phycocyanin (PC) concentrations in inland waters. This study aimed at identifying the influence of the algorithm parameters and wavelength bands on output variables and searching optimal parameter values. The opt...

  13. Argo Float Data from the APDRC DAPPER Server, 1995-present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The floats are designed to drift at a fixed pressure (usually 1000 dbar) for 10 days. After this period, the floats move to a profiling pressure (usually between...

  14. Transforming Ocean Observations of the Carbon Budget, Acidification, Hypoxia, Nutrients, and Biological Productivity: a Global Array of Biogeochemical Argo Floats

    Science.gov (United States)

    Talley, L. D.; Johnson, K. S.; Claustre, H.; Boss, E.; Emerson, S. R.; Westberry, T. K.; Sarmiento, J. L.; Mazloff, M. R.; Riser, S.; Russell, J. L.

    2017-12-01

    ), and Indian Ocean (IOBioArgo). As examples, bio-optical sensors are identifying regional anomalies in light attenuation/scattering, with implications for ocean productivity and carbon export; SOCCOM floats show high CO2 outgassing in the Antarctic Circumpolar Current, due to previously unmeasured winter fluxes.

  15. Seasonal variability in bio-optical properties along the coastal waters off Cochin

    Science.gov (United States)

    Vishnu, P. S.; Shaju, S. S.; Tiwari, S. P.; Menon, Nandini; Nashad, M.; Joseph, C. Ajith; Raman, Mini; Hatha, Mohamed; Prabhakaran, M. P.; Mohandas, A.

    2018-04-01

    Strong seasonal upwelling, downwelling, changes in current patterns and the volume of freshwater discharge from Cochin Estuary defines the coastal waters off Cochin. These coastal waters were investigated through monthly sampling efforts during March 2015 to February 2016 to study the seasonal and spatial variability in bio-optical properties for the four different seasons mainly Spring Inter Monsoon (SIM), South West Monsoon (SWM), Fall Inter Monsoon (FIM) and Winter Monsoon (WM). The Barmouth region is the meeting place where freshwater from Cochin Estuary directly enters to the sea through a single narrow outlet, was dominated by highly turbid waters during the entire period of study. Among the four seasons, chlorophyll a (Chl_a) concentration showed a high value during SWM, ranged from 2.90 to 11.66 mg m-3 with an average value of 6.56 ± 3.51 mg m-3. During SIM the distribution of coloured dissolved organic matter (CDOM) is controlled by decomposition of phytoplankton biomass and the river discharge, whereas during SWM the temporal distribution of CDOM is controlled only by river discharge. The highest value for CDOM spectral slope (SCDOM) was observed during SWM, ranged from 0.013 to 0.020 nm-1 with an average value of 0.015 ± 0.002 nm-1. During WM, the high SCDOM with lower aCDOM (443) indicates the photo-degradation affects the absorption characteristics of CDOM. The observed nonlinearity between Chl_a and the ratio of phytoplankton absorption aph (443)/aph (670) indicating the packaging effect and changes in the intercellular composition of pigments. During the study period, aph (670) was strongly correlated with Chl_a than aph (443), which explains the accessory pigment absorption dominating more than Chl_a in the blue part of the spectrum. Similarly, the results obtained from seasonal bio-optical data indicating that Chl_a significantly contributes light attenuation of the water column during SIM, whereas detritus (ad) significantly contributes light

  16. Seasonal variability in bio-optical properties along the coastal waters off Cochin

    KAUST Repository

    Vishnu, P.S.

    2017-12-15

    Strong seasonal upwelling, downwelling, changes in current patterns and the volume of freshwater discharge from Cochin Estuary defines the coastal waters off Cochin. These coastal waters were investigated through monthly sampling efforts during March 2015 to February 2016 to study the seasonal and spatial variability in bio-optical properties for the four different seasons mainly Spring Inter Monsoon (SIM), South West Monsoon (SWM), Fall Inter Monsoon (FIM) and Winter Monsoon (WM). The Barmouth region is the meeting place where freshwater from Cochin Estuary directly enters to the sea through a single narrow outlet, was dominated by highly turbid waters during the entire period of study. Among the four seasons, chlorophyll a (Chl_a) concentration showed a high value during SWM, ranged from 2.90 to 11.66 mg m−3 with an average value of 6.56 ± 3.51 mg m−3. During SIM the distribution of coloured dissolved organic matter (CDOM) is controlled by decomposition of phytoplankton biomass and the river discharge, whereas during SWM the temporal distribution of CDOM is controlled only by river discharge. The highest value for CDOM spectral slope (SCDOM) was observed during SWM, ranged from 0.013 to 0.020 nm−1 with an average value of 0.015 ± 0.002 nm−1. During WM, the high SCDOM with lower aCDOM (443) indicates the photo-degradation affects the absorption characteristics of CDOM. The observed nonlinearity between Chl_a and the ratio of phytoplankton absorption aph (443)/aph (670) indicating the packaging effect and changes in the intercellular composition of pigments. During the study period, aph (670) was strongly correlated with Chl_a than aph (443), which explains the accessory pigment absorption dominating more than Chl_a in the blue part of the spectrum. Similarly, the results obtained from seasonal bio-optical data indicating that Chl_a significantly contributes light attenuation of the water column during SIM, whereas detritus (ad

  17. Bio-optical Properties of Cyanobacteria Blooms in Western Lake Erie

    Directory of Open Access Journals (Sweden)

    Timothy S. Moore

    2017-09-01

    Full Text Available There is a growing use of remote sensing observations for detecting and quantifying freshwater cyanobacteria populations, yet the inherent optical properties of these communities in natural settings, fundamental to bio-optical algorithms, are not well known. Toward bridging this knowledge gap, we measured a full complement of optical properties in western Lake Erie during cyanobacteria blooms in the summers of 2013 and 2014. Our measurements focus attention on the optical uniqueness of cyanobacteria blooms, which have consequences for remote sensing and bio-optical modeling. We found the cyanobacteria blooms in the western basin during our field work were dominated by Microcystis, while the waters in the adjacent central basin were dominated by Planktothrix. Chlorophyll concentrations ranged from 1 to over 135 μg/L across the study area with the highest concentrations associated with Microcystis in the western basin. We observed large, amorphous colonial Microcystis structures in the bloom area characterized by high phytoplankton absorption and high scattering coefficients with a mean particle backscatter ratio at 443 nm > 0.03, which is higher than other plankton types and more comparable to suspended inorganic sediments. While our samples contained mixtures of both, our analysis suggests high contributions to the measured scatter and backscatter coefficients from cyanobacteria. Our measurements provide new insights into the optical properties of cyanobacteria blooms, and indicate that current semi-analytic models are likely to have problems resolving a closed solution in these types of waters as many of our observations are beyond the range of existing model components. We believe that different algorithm or model approaches are needed for these conditions, specifically for phytoplankton absorption and particle backscatter components. From a remote sensing perspective, this presents a challenge not only in terms of a need for new algorithms

  18. A bio-optical model suitable for use in forward and inverse coupled atmosphere-ocean radiative transfer models

    International Nuclear Information System (INIS)

    Zhang Kexin; Li Wei; Eide, Hans; Stamnes, Knut

    2007-01-01

    A simple, yet complete bio-optical model for the inherent optical properties (IOPs) of oceanic waters is developed. This bio-optical model is specifically designed for use in comprehensive, multiple scattering radiative transfer models for the coupled atmosphere-ocean system. Such models can be used to construct next-generation algorithms for simultaneous retrieval of aerosol and marine parameters. The computed remote sensing reflectance R rs (λ) is validated against field measurements of R rs (λ) compiled in the SeaBASS data base together with simultaneous chlorophyll concentrations (C) ranging from 0.03 to 100mgm -3 . This connection between R rs and C is used to construct a chlorophyll concentration retrieval algorithm that yields reliable results for a large range of chlorophyll concentrations. The overall performance of a MODIS/VIIRS chlorophyll concentration retrieval algorithm is found to be less satisfactory

  19. Bio-optical characterization in an ultra-oligotrophic region: the North central Red Sea

    KAUST Repository

    Kheireddine, Malika

    2015-04-01

    Until recently, satellite-derived ocean color observations have been the only means of evaluating optical variability of the Red Sea. During a cruise in autumn 2014, we investigated the variability of Inherent Optical Properties (IOPs) in the North Central Red Sea (NCRS) with a particular focus on the particulate backscattering coefficient, bbp, and colored dissolved organic matter, CDOM, absorption. To our knowledge, these are some of the measurements of these properties in the Red Sea. The IOPs are derived from the concentration and physical properties of suspended particles in the ocean. They provide a simple description of the influence of these particles on the light within the water column. Bio-optical relationships found for ultra-oligotrophic waters of the six stations sampled significantly depart from the mean standard relationships provided for the global ocean, showing the peculiar character of the Red Sea. These optical anomalies relate to the specific biological and environmental conditions occurring in the Red Sea ecosystem. Specifically, the surface specific phytoplankton absorption coefficients are lower than the values predicted from the global relationships due to a high proportion of relatively large sized phytoplankton. Conversely, bbp values are much higher than the mean standard values for a given chlorophyll-a concentration, Chl a. This presumably results from the influence of highly refractive submicrometer particles of Saharan origin in the surface layer of the water column.

  20. The potential for bio-optical imaging of biomaterial-associated infection in vivo.

    Science.gov (United States)

    Sjollema, Jelmer; Sharma, Prashant K; Dijkstra, Rene J B; van Dam, Gooitzen M; van der Mei, Henny C; Engelsman, Anton F; Busscher, Henk J

    2010-03-01

    This review presents the current state of Bioluminescence and Fluorescent Imaging technologies (BLI and FLI) as applied to Biomaterial-Associated Infections (BAI). BLI offers the opportunity to observe the in vivo course of BAI in small animals without the need to sacrifice animals at different time points after the onset of infection. BLI is highly dependent on the bacterial cell metabolism which makes BLI a strong reporter of viable bacterial presence. Fluorescent sources are generally more stable than bioluminescent ones and specifically targeted, which renders the combination of BLI and FLI a promising tool for imaging BAI. The sensitivity and spatial resolution of both imaging tools are, however, dependent on the imaging system used and the tissue characteristics, which makes the interpretation of images, in terms of the location and shape of the illuminating source, difficult. Tomographic reconstruction of the luminescent source is possible in the most modern instruments, enabling exact localization of a colonized implant material, spreading of infecting organisms in surrounding tissue and immunological tissue reactions. BLI studies on BAI have successfully distinguished between different biomaterials with respect to the development and clearance of BAI in vivo, simultaneously reducing animal use and experimental variation. It is anticipated that bio-optical imaging will become an indispensable technology for the in vivo evaluation of antimicrobial coatings. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  1. Sensitivity analysis of a bio-optical model for Italian lakes focused on Landsat-8, Sentinel-2 and Sentinel-3

    Science.gov (United States)

    Manzo, Ciro; Bresciani, Mariano; Giardino, Claudia; Braga, Federica; Bassani, Cristiana

    2015-04-01

    In this work, a variance-based procedure was applied to study the sensitivity of a Case-2 bio-optical model which simulates the water reflectance of three Italian lakes - Garda, Mantua and Trasimeno - with different trophic conditions by analysing the main effect of single WQPs and their interactions. The water reflectance was simulated according to a four-components model [Brando and Dekker 2003] considering the SIOPs typical of each lake and the spectral characteristics of three optical sensors, on-board of Landsat-8, Sentinel-2 and Sentinel-3, which can be potentially applied for lakes. Lakes Garda, Mantua and Trasimeno were selected as representative of different trophic levels; for these lakes long-term data of in situ measurements on water quality characteristics were also available. The bio-optical analytical model simulated the subsurface irradiance reflectance R(0-, λ) as a function of absorption and backscattering coefficients (a(λ), bb(λ)) given as a sum of the contribution of water and the water quality parameters. The sensitivity indices of water reflectance for three water types/trophic conditions were calculated decomposing output variance (V) in partial variances which represent the share of V that is explained by the bio-optical model inputs [Saltelli et al., 2010]. The results provide important information relating the sensitivity of the new generation sensors to different trophic statuses, and in particular confirmed that Sentinel-3 water reflectance is sensitive to WQPs in all the trophic conditions investigated.

  2. Temperature and pressure data collected using drifting buoy and profiling floats from the North Atlantic Ocean in part of the IDOE/POLYMODE (International Decade of Ocean Exploration / combination of USSR POLYGON project and US MODE) from 1975-01-10 to 1981-05-31 (NODC Accession 8700121)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature and pressure data were collected using drifting buoy and profiling floats from CHAIN, GILLISS, OCEANUS, and ENDEAVOR from the North Atlantic Ocean from...

  3. Bio-optical data integration based on a 4 D database system approach

    Science.gov (United States)

    Imai, N. N.; Shimabukuro, M. H.; Carmo, A. F. C.; Alcantara, E. H.; Rodrigues, T. W. P.; Watanabe, F. S. Y.

    2015-04-01

    Bio-optical characterization of water bodies requires spatio-temporal data about Inherent Optical Properties and Apparent Optical Properties which allow the comprehension of underwater light field aiming at the development of models for monitoring water quality. Measurements are taken to represent optical properties along a column of water, and then the spectral data must be related to depth. However, the spatial positions of measurement may differ since collecting instruments vary. In addition, the records should not refer to the same wavelengths. Additional difficulty is that distinct instruments store data in different formats. A data integration approach is needed to make these large and multi source data sets suitable for analysis. Thus, it becomes possible, even automatically, semi-empirical models evaluation, preceded by preliminary tasks of quality control. In this work it is presented a solution, in the stated scenario, based on spatial - geographic - database approach with the adoption of an object relational Database Management System - DBMS - due to the possibilities to represent all data collected in the field, in conjunction with data obtained by laboratory analysis and Remote Sensing images that have been taken at the time of field data collection. This data integration approach leads to a 4D representation since that its coordinate system includes 3D spatial coordinates - planimetric and depth - and the time when each data was taken. It was adopted PostgreSQL DBMS extended by PostGIS module to provide abilities to manage spatial/geospatial data. It was developed a prototype which has the mainly tools an analyst needs to prepare the data sets for analysis.

  4. Bio-optical sensor for brain activity measurement based on whispering gallery modes

    Science.gov (United States)

    Ali, Amir R.; Massoud, Yasmin M.

    2017-05-01

    In this paper, a high-resolution bio-optical sensor is developed for brain activity measurement. The aim is to develop an optical sensor with enough sensitivity to detect small electric field perturbations caused by neuronal action potential. The sensing element is a polymeric dielectric micro-resonator fabricated in a spherical shape with a few hundred microns in diameter. They are made of optical quality polymers that are soft which make them mechanically compatible with tissue. The sensors are attached to or embedded in optical fibers which serve as input/output conduits for the sensors. Hundreds or even thousands of spheres can be attached to a single fiber to detect and transmit signals at different locations. The high quality factor for the optical resonator makes it significantly used in such bio-medical applications. The sensing phenomenon is based on whispering gallery modes (WGM) shifts of the optical sensor. To mimic the brain signals, the spherical resonator is immersed in a homogeneous electrical field that is created by applying potential difference across two metallic plates. One of the plates has a variable voltage while the volt on the other plate kept fixed. Any small perturbations of the potential difference (voltage) lead to change in the electric field intensity. In turn the sensor morphology will be affected due to the change in the electrostriction force acting on it causing change in its WGM. By tracking these WGM shift on the transmission spectrum, the induced potential difference (voltage change) could be measured. Results of a mathematical model simulation agree well with the preliminary experiments. Also, the results show that the brain activity could be measured using this principle.

  5. Evaluating Southern Ocean Carbon Eddy-Pump From Biogeochemical-Argo Floats

    Science.gov (United States)

    Llort, Joan; Langlais, C.; Matear, R.; Moreau, S.; Lenton, A.; Strutton, Peter G.

    2018-02-01

    The vertical transport of surface water and carbon into ocean's interior, known as subduction, is one of the main mechanisms through which the ocean influences Earth's climate. New instrumental approaches have shown the occurrence of localized and intermittent subduction episodes associated with small-scale ocean circulation features. These studies also revealed the importance of such events for the export of organic matter, the so-called eddy-pump. However, the transient and localized nature of episodic subduction hindered its large-scale evaluation to date. In this work, we present an approach to detect subduction events at the scale of the Southern Ocean using measurements collected by biogeochemical autonomous floats (BGCArgo). We show how subduction events can be automatically identified as anomalies of spiciness and Apparent Oxygen Utilization (AOU) below the mixed layer. Using this methodology over more than 4,000 profiles, we detected 40 subduction events unevenly distributed across the Sothern Ocean. Events were more likely found in hot spots of eddy kinetic energy (EKE), downstream major bathymetric features. Moreover, the bio-optical measurements provided by BGCArgo allowed measuring the amount of Particulate Organic Carbon (POC) being subducted and assessing the contribution of these events to the total downward carbon flux at 100 m (EP100). We estimated that the eddy-pump represents less than 19% to the EP100 in the Southern Ocean, although we observed particularly strong events able to locally duplicate the EP100. This approach provides a novel perspective on where episodic subduction occurs that will be naturally improved as BGCArgo observations continue to increase.

  6. Insight study of the bio-optical algorithms for chlorophyll-a and cyanobacteria with sensitivity analysis and multi-objective algorithm

    Science.gov (United States)

    Pyo, JongCheol; Baek, SangSoo; Park, SangHun; Kwon, YongSung; Kim, MinJeong; Ligaray, Mayzonee; Yoon, SeongHyun; Sin, Jihun; Park, Yongeun; Cha, YoonKyung; Cho, KyungHwa

    2017-04-01

    In recent years, severe degradation of drinking water quality has been observed more frequently due to severe eutrophication. This kind of environmental issue is mainly caused by anthropogenic activities like rapid growths of agricultures and industries. Therefore, the water degradation will be observed which could significantly affect humans and the aquatic ecosystem. Based on these environmental situations, the efficient management of drinking water system is necessary. To address this issue, many researches have implemented the monitoring of algae to predict their concentration or the development of new technology for the elimination of algae. The representative one is a remote sensing technique. In remote sensing research area, a lot of bio-optical algorithms has been developed to estimate the chlorophyll-a or phycocyanin concentration in the fresh water system. These bio-optical algorithms have many parameters and wavelengths to evaluate the algae concentration. However, the understanding of the specific parameters and the wavelengths is not enough since the bio-optical properties are not universal in terms of the different water environment. Thus, this study implemented that the major bio-optical algorithms (i.e. Gons, Gilerson, Ritchie, Simis, Duan, and Li algorithms) were tested their performances for the estimation of the chlorophyll-a and phycocyanin concentration with the observation data. And, the parameters and wavelengths were analyzed their sensitivity which could reveal the relationship and effectiveness between these parameters. Then, the optimization process was implemented to find out the optimal parameters and wavelengths for Korea water system. Finally, these results were compared to the other researches which used same major bio-optical algorithms but had different study site to identify the insight meaning of the parameters and wavelengths in Korea water system. Therefore, the knowledges from this research could be the foundation to

  7. Net community production in the South China Sea Basin estimated from in situ O2 measurements on an Argo profiling float

    Science.gov (United States)

    Huang, Yibin; Yang, Bo; Chen, Bingzhang; Qiu, Guoqiang; Wang, Haili; Huang, Bangqin

    2018-01-01

    For the first time, the net community production (NCP) was estimated over a complete annual cycle in the basin of the South China Sea (SCS) using in situ oxygen measurements from an Argo profiling float and an oxygen mass balance model. The annual NCP from July 2014 to July 2015 was estimated to be 2.7 mol C m-2 yr-1 (calculated to the deepest winter mixed layer depth of 56 m), with the uncertainties ranging from 0.9 2.2 mol C m-2 yr-1. NCP estimates followed a monsoonal pattern with higher values in the cold season (November to April) when northeast monsoon prevailed and low values in the warm season (June to September) when this area was dominated by the southwest monsoon. Most of the net heterotrophic events occurred in the warm season. The magnitude and seasonal pattern derived from our results agree with previous export production studies based on discrete measurements. Comparison with satellite-derived NCP revealed that the results derived with NPP from Carbon-based Production Model (CbPM) were closer to the Argo measurements than the results derived with NPP from Vertically Generalized Production Model (VGPM) in magnitude; while the VGPM-based approach did a better job in reproducing the seasonal cycle of NCP in this area. This novel approach provides the possibilities to study the carbon cycle in the SCS with a much higher temporal and spatial resolution, as well as more insights for metabolic state in the oligotrophic subtropical gyres.

  8. Microbial screening for quinolones residues in cow milk by bio-optical method.

    Science.gov (United States)

    Appicciafuoco, Brunella; Dragone, Roberto; Frazzoli, Chiara; Bolzoni, Giuseppe; Mantovani, Alberto; Ferrini, Anna Maria

    2015-03-15

    The use of antibiotics on lactating cows should be monitored for the possible risk of milk contamination with residues. Accordingly, Maximum Residue Levels (MRLs) are established by the European Commission to guarantee consumers safety. As pointed out by Dec 2002/657/EC, screening is the first step in the strategy for antibiotic residue control, thus playing a key role in the whole control procedure. However, current routine screening methods applied in milk chain still fail to detect residues of quinolones at concentrations of interest. This paper reports the findings of a new bio-optical method for the screening of quinolones residues in bovine milk, based on E. coli ATCC 11303 growth inhibition. The effect of blank and spiked cow milk samples (aliquots equivalents to 0.8%, v/v) is evaluated in Mueller Hinton Broth (MHb) and MHb enriched with MgSO4 2% (MHb-Mg) inoculated with the test strain at the concentration of 10(4)CFU/mL. The presence of quinolones inhibits the cellular growth in MHb, while this effect is neutralized in MHb-Mg allowing both detection and presumptive identification of quinolones. Growth of the test strain is monitored at 37 °C in a Bioscreen C automated system, and Optical Density (OD) at 600 nm is recorded every 10 min after shaking for 10s. Growth curves (OD vs. time) of E. coli ATCC 11303 are assessed in milk samples, with and without quinolones, and their differences in terms of ΔOD (ΔOD600nm=ODMHb-Mg-ODMHb) are calculated. The presence of quinolones is detected by the cellular growth inhibition (OD vs time, none increase in the value OD) and presumptively identified through the increase of the slope of ΔOD600nm curve (ΔOD vs. time), after about 3h of incubation. The detection limit for ciprofloxacin and enrofloxacin is at the level of MRL, for marbofloxacin is at 2-fold the MRL whereas for danofloxacin is at 4-fold the MRL. Although the sensitivity of the method could be further improved and the procedure automated, it is a

  9. Assimilating bio-optical glider data during a phytoplankton bloom in the southern Ross Sea

    Science.gov (United States)

    Kaufman, Daniel E.; Friedrichs, Marjorie A. M.; Hemmings, John C. P.; Smith, Walker O., Jr.

    2018-01-01

    The Ross Sea is a region characterized by high primary productivity in comparison to other Antarctic coastal regions, and its productivity is marked by considerable variability both spatially (1-50 km) and temporally (days to weeks). This variability presents a challenge for inferring phytoplankton dynamics from observations that are limited in time or space, which is often the case due to logistical limitations of sampling. To better understand the spatiotemporal variability in Ross Sea phytoplankton dynamics and to determine how restricted sampling may skew dynamical interpretations, high-resolution bio-optical glider measurements were assimilated into a one-dimensional biogeochemical model adapted for the Ross Sea. The assimilation of data from the entire glider track using the micro-genetic and local search algorithms in the Marine Model Optimization Testbed improves the model-data fit by ˜ 50 %, generating rates of integrated primary production of 104 g C m-2 yr-1 and export at 200 m of 27 g C m-2 yr-1. Assimilating glider data from three different latitudinal bands and three different longitudinal bands results in minimal changes to the simulations, improves the model-data fit with respect to unassimilated data by ˜ 35 %, and confirms that analyzing these glider observations as a time series via a one-dimensional model is reasonable on these scales. Whereas assimilating the full glider data set produces well-constrained simulations, assimilating subsampled glider data at a frequency consistent with cruise-based sampling results in a wide range of primary production and export estimates. These estimates depend strongly on the timing of the assimilated observations, due to the presence of high mesoscale variability in this region. Assimilating surface glider data subsampled at a frequency consistent with available satellite-derived data results in 40 % lower carbon export, primarily resulting from optimized rates generating more slowly sinking diatoms. This

  10. Optimized extraction of daily bio-optical time series derived from MODIS/Aqua imagery for Lake Tanganyika, Africa

    DEFF Research Database (Denmark)

    Horion, Stéphanie; Bergamino, N; Stenuite, S

    2010-01-01

    algorithm is possible; and (iii) K490 estimates provide a good level of significance. The resulting validated time series of bio-optical properties provides a fundamental information base for the study of phytoplankton and primary production dynamics and interannual trends. A comparison between surface...... is a fundamental tool for understanding and monitoring these changes. We developed an approach to create a regionally calibrated dataset of chlorophyll-a concentrations (CHL) and attenuation coefficients at 490 nm (K490) for the period from July 2002 to December 2006 using daily calibrated radiances retrieved from...

  11. Decadal trends and common dynamics of the bio-optical and thermal characteristics of the African Great Lakes.

    Directory of Open Access Journals (Sweden)

    Steven Loiselle

    Full Text Available The Great Lakes of East Africa are among the world's most important freshwater ecosystems. Despite their importance in providing vital resources and ecosystem services, the impact of regional and global environmental drivers on this lacustrine system remains only partially understood. We make a systematic comparison of the dynamics of the bio-optical and thermal properties of thirteen of the largest African lakes between 2002 and 2011. Lake surface temperatures had a positive trend in all Great Lakes outside the latitude of 0° to 8° south, while the dynamics of those lakes within this latitude range were highly sensitive to global inter-annual climate drivers (i.e. El Niño Southern Oscillation. Lake surface temperature dynamics in nearly all lakes were found to be sensitive to the latitudinal position of the Inter Tropical Convergence Zone. Phytoplankton dynamics varied considerably between lakes, with increasing and decreasing trends. Intra-lake differences in both surface temperature and phytoplankton dynamics occurred for many of the larger lakes. This inter-comparison of bio-optical and thermal dynamics provides new insights into the response of these ecosystems to global and regional drivers.

  12. Chlorophyll-a concentration estimation with three bio-optical algorithms: correction for the low concentration range for the Yiam Reservoir, Korea

    Science.gov (United States)

    Bio-optical algorithms have been applied to monitor water quality in surface water systems. Empirical algorithms, such as Ritchie (2008), Gons (2008), and Gilerson (2010), have been applied to estimate the chlorophyll-a (chl-a) concentrations. However, the performance of each algorithm severely degr...

  13. Floating offshore turbines

    DEFF Research Database (Denmark)

    Tande, John Olav Giæver; Merz, Karl; Schmidt Paulsen, Uwe

    2014-01-01

    Floating wind turbines enable harvesting the offshore wind resources over deep sea. About 20 concepts are under development, at varying stages of maturity. Two concepts are demonstrated in full scale; these are HyWind and WindFloat. Both employ a standard on-shore wind turbine with only minor...... modifications, but on a spar and a semi-submersible floater, respectively. Other concepts suggest new types of turbines, e.g., the DeepWind concept consisting of a vertical axis turbine and a subsea generator. The three concepts represent different approaches: HyWind and WindFloat are already in a demonstration...... metric of energy production per unit steel mass. Floating offshore wind turbines represent a promising technology. The successful operation of HyWind and WindFloat in full scale demonstrates a well advanced technology readiness level, where further development will go into refining the concepts, cost...

  14. Bilateral Floating Hip and Floating Knee: a Rare Complex Injury ...

    African Journals Online (AJOL)

    We report a rare complex injury of a 45-year-old man who sustained a bilateral floating hip and floating knee and hospitalised in our service six days after a traffic accident. The floating knees were open type III and II of Cauchoix score in phase of suppuration. He also presented with a floating ankle on the right side.

  15. FLOAT Project - Task 1

    DEFF Research Database (Denmark)

    Marchalot, Tanguy; Kofoed, Jens Peter; Sørensen, Eigil V.

    The objective of the FLOAT project is to study the reliability of high-performance fibre-reinforced concrete, also known as Compact Reinforced Composite (CRC), for the floats of wave energy converters. In order to reach commercial breakthrough, wave energy converters need to achieve a lower price.......com, 2011). CRC floats could be a very cost-effective technology with enhanced loading capacity and environmental resistance, and very low maintenance requirements, affecting directly the final energy price. The project involves DEXA Wave Energy Ltd, Wave Star A/S, Aalborg University and Hi-Con A...

  16. The Ocean Colour Climate Change Initiative: III. A Round-Robin Comparison on In-Water Bio-Optical Algorithms

    Science.gov (United States)

    Brewin, Robert J.W.; Sathyendranath, Shubha; Muller, Dagmar; Brockmann, Carsten; Deschamps, Pierre-Yves; Devred, Emmanuel; Doerffer, Roland; Fomferra, Norman; Franz, Bryan; Grant, Mike; hide

    2013-01-01

    Satellite-derived remote-sensing reflectance (Rrs) can be used for mapping biogeochemically relevant variables, such as the chlorophyll concentration and the Inherent Optical Properties (IOPs) of the water, at global scale for use in climate-change studies. Prior to generating such products, suitable algorithms have to be selected that are appropriate for the purpose. Algorithm selection needs to account for both qualitative and quantitative requirements. In this paper we develop an objective methodology designed to rank the quantitative performance of a suite of bio-optical models. The objective classification is applied using the NASA bio-Optical Marine Algorithm Dataset (NOMAD). Using in situ Rrs as input to the models, the performance of eleven semianalytical models, as well as five empirical chlorophyll algorithms and an empirical diffuse attenuation coefficient algorithm, is ranked for spectrally-resolved IOPs, chlorophyll concentration and the diffuse attenuation coefficient at 489 nm. The sensitivity of the objective classification and the uncertainty in the ranking are tested using a Monte-Carlo approach (bootstrapping). Results indicate that the performance of the semi-analytical models varies depending on the product and wavelength of interest. For chlorophyll retrieval, empirical algorithms perform better than semi-analytical models, in general. The performance of these empirical models reflects either their immunity to scale errors or instrument noise in Rrs data, or simply that the data used for model parameterisation were not independent of NOMAD. Nonetheless, uncertainty in the classification suggests that the performance of some semi-analytical algorithms at retrieving chlorophyll is comparable with the empirical algorithms. For phytoplankton absorption at 443 nm, some semi-analytical models also perform with similar accuracy to an empirical model. We discuss the potential biases, limitations and uncertainty in the approach, as well as additional

  17. OCTS and SeaWiFS Bio-Optical Algorithm and Product Validation and Intercomparison in US Coastal Waters

    Science.gov (United States)

    Brown, Christopher W.; Brock, John C.

    1998-01-01

    The successful launch of the National Space Development Agency of Japan (NASDA) Ocean Color and Temperature Sensor (OCTS) in August 1996, and the launch of Orbital Science Corporation's (OSC) Sea-viewing Wide-Field-of-view Sensor (SeaWiFS) in August 1997 signaled the beginning of a new era for ocean color research and application. These data may be used to remotely evaluate 1) water quality, 2) transport of sediments and adhered pollutants, 3) primary production, upon which commercial shellfish and finfish populations depend for food, and 4) harmful algal blooms which pose a threat to public health and economies of affected areas. Several US government agencies have recently expressed interest in monitoring U.S. coastal waters using optical remote sensing. This renewed interest is broadly driven by 1) resource management concerns over the impact of coastward shifts in population and land use on the ecosystems of estuaries, wetlands, nearshore benthic environments and fisheries, 2) recognition of the need to understand short time scale global change due to urbanization of sensitive land-margin ecosystems, and 3) national security issues. Satellite ocean color sensors have the potential to furnish data at the appropriate time and space scales to evaluate and resolve these concerns and problems. In this draft technical memorandum, we outline our progress during the first year of our SIMBIOS project to evaluate ocean color bio-optical algorithms and products generated using OCTS and SeaWiFS data in coastal US waters.

  18. Naval Research Laboratory Ecological -- Photochemical -- Bio-optical--Numerical Experiment (Neptune) Version 1: A Portable, Flexible Modeling Environment Designed to Resolve Time-dependent Feedbacks Between Upper Ocean Ecology, Photochemistry, and Optics

    National Research Council Canada - National Science Library

    Jolliff, Jason K; Kindle, John C

    2007-01-01

    A modeling system has been constructed that combines ecological element cycling, photochemical processes, and bio-optical processes into a single simulation that may be coupled to hydrodynamic models...

  19. Nearshore physical processes and bio-optical properties in the New York Bight

    Science.gov (United States)

    Chang, G. C.; Dickey, T. D.; Schofield, O. M.; Weidemann, A. D.; Boss, E.; Pegau, W. S.; Moline, M. A.; Glenn, S. M.

    2002-09-01

    Temporal and spatial variability of physical, biological, and optical properties on scales of minutes to months and meters to ˜50 km are examined using an extensive data set collected on the New York Bight continental shelf during the Hyperspectral Coastal Ocean Dynamics Experiment. Measurements from a midshelf mooring and bottom tripod (˜25 km offshore, 24 m water depth) and two nearshore profiling nodes (˜5 km offshore, 15 m water depth) are utilized to quantify and correlate midshelf and nearshore variability. Towed shipboard undulating profilers and a high-frequency radar (CODAR) array provide complementary spatial data. We show that phytoplankton and dissolved matter each accounted for roughly 50% of total absorption (440 nm) at midshelf. In contrast, particulate compared to gelbstoff absorption dominated total absorption at the nearshore location. A relatively high-salinity, low-temperature, low particulate coastal jet decreased turbidity nearshore and advected lower-salinity, higher-chlorophyll waters to the midshelf region, resulting in increased biomass at midshelf. Small-scale (order of a few kilometers) convergence and divergence zones formed from the interaction of semidiurnal tides with mean currents and a water mass/turbidity front. The front resulted in increased decorrelation scales from nearshore (˜1 day) toward midshelf (2-3 days) for optical and biological parameters. We conclude that optical and biological variability and distributions at midshelf and nearshore locations were influenced mainly by semidiurnal tides and the coastal jet. We present insights into nearshore coastal processes and their effects on biology and optics as well as for the design of future nearshore interdisciplinary coastal programs.

  20. Gross community production and metabolic balance in the South Pacific Gyre, using a non intrusive bio-optical method

    Directory of Open Access Journals (Sweden)

    H. Claustre

    2008-03-01

    Full Text Available The very clear waters of the South Pacific Gyre likely constitute an end-member of oligotrophic conditions which remain essentially unknown with respect to its impact on carbon fixation and exportation. We describe a non-intrusive bio-optical method to quantify the various terms of a production budget (Gross community production, community losses, net community production in this area. This method is based on the analysis of the diel cycle in Particulate Organic Carbon (POC, derived from high frequency measurements of the particle attenuation coefficient cp. We report very high integrated rates of Gross Community Production within the euphotic layer (average of 846±484 mg C m−2 d−1 for 17 stations that are far above any rates determined using incubation techniques for such areas. Furthermore we show that the daily production of POC is essentially balanced by the losses so that the system cannot be considered as net heterotrophic. Our results thus agree well with geochemical methods, but not with incubation studies based on oxygen methods. We stress to the important role of deep layers, below the euphotic layer, in contributing to carbon fixation when incident irradiance at the ocean surface is high (absence of cloud coverage. These deep layers, not considered up to know, might fuel part of the heterotrophic processes in the upper layer, including through dissolved organic carbon. We further demonstrate that, in these extremely clear and stratified waters, integrated gross community production is proportional to the POC content and surface irradiance via an efficiency index ψ GCP*, the water column cross section for Gross Community Production. We finally discuss our results in the context of the role of oligotrophic gyre in the global carbon budget and of the possibility of using optical proxies from space for the development of growth community rather than primary production

  1. Performance of operational satellite bio-optical algorithms in different water types in the southeastern Arabian Sea

    Directory of Open Access Journals (Sweden)

    P. Minu

    2016-10-01

    Full Text Available The in situ remote sensing reflectance (Rrs and optically active substances (OAS measured using hyperspectral radiometer, were used for optical classification of coastal waters in the southeastern Arabian Sea. The spectral Rrs showed three distinct water types, that were associated with the variability in OAS such as chlorophyll-a (chl-a, chromophoric dissolved organic matter (CDOM and volume scattering function at 650 nm (β650. The water types were classified as Type-I, Type-II and Type-III respectively for the three Rrs spectra. The Type-I waters showed the peak Rrs in the blue band (470 nm, whereas in the case of Type-II and III waters the peak Rrs was at 560 and 570 nm respectively. The shifting of the peak Rrs at the longer wavelength was due to an increase in concentration of OAS. Further, we evaluated six bio-optical algorithms (OC3C, OC4O, OC4, OC4E, OC3M and OC4O2 used operationally to retrieve chl-a from Coastal Zone Colour Scanner (CZCS, Ocean Colour Temperature Scanner (OCTS, Sea-viewing Wide Field-of-view Sensor (SeaWiFS, MEdium Resolution Imaging Spectrometer (MERIS, Moderate Resolution Imaging Spectroradiometer (MODIS and Ocean Colour Monitor (OCM2. For chl-a concentration greater than 1.0 mg m−3, algorithms based on the reference band ratios 488/510/520 nm to 547/550/555/560/565 nm have to be considered. The assessment of algorithms showed better performance of OC3M and OC4. All the algorithms exhibited better performance in Type-I waters. However, the performance was poor in Type-II and Type-III waters which could be attributed to the significant co-variance of chl-a with CDOM.

  2. Assessment of the abnormal growth of floating macrophytes in Winam Gulf (Kenya) by using MODIS imagery time series

    Science.gov (United States)

    Fusilli, L.; Collins, M. O.; Laneve, G.; Palombo, A.; Pignatti, S.; Santini, F.

    2013-02-01

    The objective of this research study is to assess the capability of time-series of MODIS imagery to provide information suitable for enhancing the understanding of the temporal cycles shown by the abnormal growth of the floating macrophytes in order to support monitoring and management action of Lake Victoria water resources. The proliferation of invasive plants and aquatic weeds is of growing concern. Starting from 1989, Lake Victoria has been interested by the high infestation of water hyacinth with significant socio-economic impact on riparian populations. In this paper, we describe an approach based on the time-series of MODIS to derive the temporal behaviour, the abundance and distribution of the floating macrophytes in the Winam Gulf (Kenyan portion of the Lake Victoria) and its possible links to the concentrations of the main water constituencies. To this end, we consider the NDVI values computed from the MODIS imagery time-series from 2000 to 2009 to identify the floating macrophytes cover and an appropriate bio-optical model to retrieve, by means of an inverse procedure, the concentrations of chlorophyll a, coloured dissolved organic matter and total suspended solid. The maps of the floating vegetation based on the NDVI values allow us to assess the spatial and temporal dynamics of the weeds with high time resolution. A floating vegetation index (FVI) has been introduced for describing the weeds pollution level. The results of the analysis show a consistent temporal relation between the water constituent concentrations within the Winam Gulf and the FVI, especially in the proximity of the greatest proliferation of floating vegetation in the last 10 years that occurred between the second half of 2006 and the first half of 2007.The adopted approach will be useful to implement an automatic system for monitoring and predicting the floating macrophytes proliferation in Lake Victoria.

  3. The floating knee

    DEFF Research Database (Denmark)

    Muñoz Vives, Josep; Bel, Jean-Christophe; Capel Agundez, Arantxa

    2016-01-01

    In 1975, Blake and McBryde established the concept of 'floating knee' to describe ipsilateral fractures of the femur and tibia.1This combination is much more than a bone lesion; the mechanism is usually a high-energy trauma in a patient with multiple injuries and a myriad of other lesions...

  4. The floating water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Woisetschlaeger, Jakob; Gatterer, Karl; Maier, Eugen; Pecnik, Rene; Holler, Gert; Eisenkoelbl, Helmut

    2007-01-01

    When high voltage is applied to distilled water filled in two glass beakers which are in contact, a stable water connection forms spontaneously, giving the impression of a floating water bridge. A detailed experimental analysis reveals static and dynamic structures as well as heat and mass transfer through this bridge

  5. The floating knee

    DEFF Research Database (Denmark)

    Muñoz Vives, Josep; Bel, Jean-Christophe; Capel Agundez, Arantxa

    2016-01-01

    fixation when both fractures (femoral and tibial) are extra-articular.Plates are the 'standard of care' in cases with articular fractures.A combination of implants are required by 40% of floating knees.Associated ligamentous and meniscal lesions are common, but may be irrelevant in the case of an intra...

  6. Acoustic Float for Marine Mammal Monitoring

    Science.gov (United States)

    2011-09-30

    development by several teams, is to equip several ocean gliders with hydrophones and marine mammal call-detection software and send them out to monitor in...real time, but the gliders are relatively expensive, at upwards of $100,000 each [Rogers et al., 2004]. A vertical profiler float has been in...inexpensive and reliable tool for oceanogrphers [Kobayashi et al., 2006]. They also can dive to 2000 m whereass Slocum gilder and Seaglider are rated

  7. Bio-Optical Properties of Two Neigboring Coastal Regions of Tropical Northern Australia: The Van Diemen Gulf and Darwin Harbour

    Directory of Open Access Journals (Sweden)

    David Blondeau-Patissier

    2017-05-01

    bio-optical relationships derived from this comprehensive set of parameters, the first ever to be collected in this tropical coastal environment, were successfully used for a region-specific seasonal parameterization a region-specific seasonally parameterized ocean color algorithm. Challenges related to the parameterization, and the use, of ocean color remote sensing algorithms for these optically complex waters are discussed.

  8. Assimilating bio-optical glider data during a phytoplankton bloom in the southern Ross Sea

    Directory of Open Access Journals (Sweden)

    D. E. Kaufman

    2018-01-01

    Full Text Available The Ross Sea is a region characterized by high primary productivity in comparison to other Antarctic coastal regions, and its productivity is marked by considerable variability both spatially (1–50 km and temporally (days to weeks. This variability presents a challenge for inferring phytoplankton dynamics from observations that are limited in time or space, which is often the case due to logistical limitations of sampling. To better understand the spatiotemporal variability in Ross Sea phytoplankton dynamics and to determine how restricted sampling may skew dynamical interpretations, high-resolution bio-optical glider measurements were assimilated into a one-dimensional biogeochemical model adapted for the Ross Sea. The assimilation of data from the entire glider track using the micro-genetic and local search algorithms in the Marine Model Optimization Testbed improves the model–data fit by  ∼ 50 %, generating rates of integrated primary production of 104 g C m−2 yr−1 and export at 200 m of 27 g C m−2 yr−1. Assimilating glider data from three different latitudinal bands and three different longitudinal bands results in minimal changes to the simulations, improves the model–data fit with respect to unassimilated data by  ∼ 35 %, and confirms that analyzing these glider observations as a time series via a one-dimensional model is reasonable on these scales. Whereas assimilating the full glider data set produces well-constrained simulations, assimilating subsampled glider data at a frequency consistent with cruise-based sampling results in a wide range of primary production and export estimates. These estimates depend strongly on the timing of the assimilated observations, due to the presence of high mesoscale variability in this region. Assimilating surface glider data subsampled at a frequency consistent with available satellite-derived data results in 40 % lower carbon export, primarily

  9. Floating self adjusting skimmer

    Energy Technology Data Exchange (ETDEWEB)

    Titus, P.E.; Hanson, J.R.

    1972-09-05

    A skimming mechanism is designed to remove all or part of a layer of oil floating on the surface of water. A pivoted receptable having a weir is buoyed to position the weir adjacent to the interface of the liquids. Liquids accumulating in the receptacle are withdrawn for disposal. A stabilizing member extends around a substantial portion of the periphery of the skimmer to prevent submergence of the weir due to wave or current movement of the liquids. (9 claims)

  10. Floating nuclear power plants

    International Nuclear Information System (INIS)

    Kindt, J.W.

    1983-01-01

    This article examines the legal regime for floating nuclear power plants (FNPs), in view of the absence of specific US legislation and the very limited references to artificial islands in the Law of the Sea Convention. The environmental impacts of FNPs are examined and changes in US regulation following the Three Mile Island accident and recent US court decisions are described. References in the Law of the Sea Convention relevant to FNPs are outlined and the current status of international law on the subject is analysed. (author)

  11. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1991 to 31 December 1991 (NODC Accession 0000387)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1991 to December 31, 1991. Data were submitted by the Institut Francais De...

  12. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1996 to 31 December 1996 (NODC Accession 0000392)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1996 to December 31, 1996. Data were submitted by Institut Francais De Recherche...

  13. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1994 to 31 December 1994 (NODC Accession 0000390)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1994 to December 31, 1994. Data were submitted by Institut Francais De Recherche...

  14. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1995 to 31 December 1995 (NODC Accession 0000391)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1995 to December 31, 1995. Data were submitted by Institut Francais De Recherche...

  15. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1992 to 31 December 1992 (NODC Accession 0000388)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1992 to December 31, 1992. Data were submitted by Institut Francais De Recherche...

  16. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1997 to 31 December 1997 (NODC Accession 0000393)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1997 to December 31, 1997. Data were submitted by the Institut Francais De...

  17. Temperature profile data from the SEA-LAND DEFENDER using bottle, CTD, profiling floats, and XBT casts in a world-wide distribution from 01 January 1993 to 31 December 1993 (NODC Accession 0000389)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from the SEA-LAND DEFENDER from January 1, 1993 to December 31, 1993. Data were submitted by Institut Francais De Recherche...

  18. Floating microspheres: a review

    Directory of Open Access Journals (Sweden)

    Jagtap Yogesh Mukund

    2012-03-01

    Full Text Available Gastric emptying is a complex process, one that is highly variable and that makes in vivo performance of drug delivery systems uncertain. A controlled drug delivery system with prolonged residence time in the stomach can be of great practical importance for drugs with an absorption window in the upper small intestine. The main limitations are attributed to the inter- and intra-subject variability of gastro-intestinal (GI transit time and to the non-uniformity of drug absorption throughout the alimentary canal. Floating or hydrodynamically controlled drug delivery systems are useful in such applications. Various gastroretentive dosage forms are available, including tablets, capsules, pills, laminated films, floating microspheres, granules and powders. Floating microspheres have been gaining attention due to the uniform distribution of these multiple-unit dosage forms in the stomach, which results in more reproducible drug absorption and reduced risk of local irritation. Such systems have more advantages over the single-unit dosage forms. The present review briefly addresses the physiology of the gastric emptying process with respect to floating drug delivery systems. The purpose of this review is to bring together the recent literature with respect to the method of preparation, and various parameters affecting the performance and characterization of floating microspheres.O esvaziamento gástrico é um processo complexo, com elevada variabilidade e responsável pela incerteza do desempenho dos medicamentos in vivo. Dessa forma, os sistemas de liberação modificada de fármacos, com tempo de residência prolongado no estômago, em especial, considerando aqueles fármacos com janela de absorção na porção superior do intestino delgado, apresentam fundamental importância. As principais limitações relativas à absorção do fármaco são, no geral, atribuídas à variabilidade inter e intra-paciente do tempo de trânsito gastro-intestinal (GI e

  19. Wave attenuation charcteristics of tethered float system

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.

    that the system performs well when it is just submerged. As float velocity decreases with increase in float size, transmission coefficient increases with increase in float size. The influence of wave period on wave attenuation is remarkable compared to other... characteristics of floating breakwaters. Seymour and Isaacs (1974), Agerton et al. (1976) and Seymour and Hanes (1979) studied the performance of a tethered float breakwater (tethered float system), assuming that drag is the major contributor-factor for wave...

  20. Floating Silicon Method

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. R/V Seward Johnson Cruise Report (SJ-9807) ACCE S-PALACE Float Deployments

    National Research Council Canada - National Science Library

    Montgomery, Ellyn

    1999-01-01

    ...). These floats are neutrally buoyant and drift with the water in which they are deployed. They are programmed to obtain temperature and salinity profiles of the top 1000 meters of the ocean every ten days...

  2. Large floating structures technological advances

    CERN Document Server

    Wang, BT

    2015-01-01

    This book surveys key projects that have seen the construction of large floating structures or have attained detailed conceptual designs. This compilation of key floating structures in a single volume captures the innovative features that mark the technological advances made in this field of engineering, and will provide a useful reference for ideas, analysis, design, and construction of these unique and emerging urban projects to offshore and marine engineers, urban planners, architects and students.

  3. Electrically floating, near vertical incidence, skywave antenna

    Science.gov (United States)

    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.

  4. Floating wind turbine system

    Science.gov (United States)

    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.

  5. Mathematical modeling of a hydrophilic cylinder floating on water.

    Science.gov (United States)

    Mao, Zai-Sha; Yang, Chao; Chen, Jiayong

    2012-07-01

    In this paper, a hydrostatic model of the surface profile anchored to the upper edge of a vertical cylinder is proposed to explain why coins can float on water surface. The sharp edge of a cylinder is thus modeled as a round smooth surface on which the contact line may be anchored at a position according to the weight of the cylinder. The mathematical model of the surface profile is established based on the hydrostatics and a third order ordinary differential equation is resulted. Numerical solution of the model demonstrates under practical conditions the existence of the surface profiles that provide reasonable uplifting force at the contact line so that the force is available for floating coins on water surface. The proposed model explains the obviously enlarged apparent contact angle and the edge effect in the literature. The numerical simulation is found in very good agreement with the experimental data in the literature. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Artisanal fishing net float loss and a proposal for a float design solution

    Directory of Open Access Journals (Sweden)

    Paulo de Tarso Chaves

    2016-03-01

    Full Text Available Abstract Plastic floats from fishing nets are commonly found washed up on beaches in southern Brazil. They are usually broken and show signs of having been repaired. Characteristics of floats and interviews with fishermen suggest two main causes of float loss. First, collisions between active gear, bottom trawl nets for shrimp, and passive gear, drift nets for fish, destroy nets and release fragments of them, including floats. Second, the difficulty with which floats are inserted on the float rope of the nets when they are used near the surface. Floats are inserted to replace damaged or lost floats, or they may be removed if it is desired that the nets be used in deeper waters. Floats may thus be poorly fixed to the cables and lost. Here a new float design that offers greater safety in use and for the replacement of floats is described and tested.

  7. Bio-Optical Properties of the Inner Continental Shelf off Santos Estuarine System, Southeastern Brazil, and their Implications for Ocean Color Algorithm Performance

    Directory of Open Access Journals (Sweden)

    Melissa Carvalho

    2014-07-01

    Full Text Available Optical characterizations of coastal water masses are important tools for a better understanding of physical and biochemical processes and aid the optimization of ocean color algorithms. In this study we present three optical classes of water observed during October/2005 and March/2006 on the inner continental shelf adjacent to Santos Bay (Brazil, based on remote sensing reflectance. ANOVA indicated a crescent estuarine influence in classes 1 to 3. Class 3 presented the highest chlorophyll-a and nutrient concentration and highest light absorption coefficients. Colored dissolved organic matter (CDOM dominated the light absorption in all classes and was strongly correlated to salinity in October/2005 due to the influence of the La Plata plume. The results indicated that CDOM dynamics in the Santos inner shelf are very complex. The performance of global chlorophyll algorithms was significantly smaller for October/2005 than for March/2006. As inconsistent changes in light absorption spectra by phytoplankton were detected between samplings, the results show that future bio-optical algorithms for this region must be optimized preferentially considering CDOM optical parameters.

  8. Strength Tests on Hulls and Floats

    Science.gov (United States)

    Matthaes, K

    1942-01-01

    The present report deals with strength tests on hulls and floats intended in part for the collection of construction data for the design of these components and in part for the stress analysis of the finished hulls and floats.

  9. Floating Microparticulate Oral Diltiazem Hydrochloride Delivery ...

    African Journals Online (AJOL)

    Purpose: To formulate and evaluate floating microparticulate oral diltiazem delivery system for possible delivery to the heart. Method: Floating microspheres were prepared using cellulose acetate and Eudragit RS100 polymers by emulsion solvent evaporation technique. The dried floating microspheres were evaluated for ...

  10. Advances in bio-optical sensing on robotic platforms to elucidate ecosystem production in the interior ocean

    Science.gov (United States)

    Walsh, I. D.; Hardman-Mountford, N.; Dufois, F.; Wojtasiewicz, B.; Slawinski, D.; Murphy, D. J.

    2016-02-01

    The global view of ocean productivity has been defined for the past three decades by satellite-derived images of optical properties of the ocean's surface layer. Yet in most of the ocean, zones of enhanced phytoplankton production and nutrient recycling are located at depths below the view of optical satellites. In the subtropical gyres, the almost ubiquitous deep chlorophyll maximum is often located at depths exceeding 100m, along density interfaces at a boundary between the down welling light flux and upward transport of nutrients. Below the chlorophyll maximum heterotrophic production is the dominant process resulting in strong oxygen consumption and dissolved nutrient regeneration. Observing the physical forcing and biogeochemical dynamics that drive this system at the relevant time scales ranging from the diel to the seasonal has been a long-standing challenge in oceanography. In particular, measuring the processes occurring through perturbations to relaxation has often been more happenstance than design. In this presentation we describe advances in sensor systems deployed on autonomous robotic profilers to quantify carbon, oxygen and nutrient cycling within the interior ocean and present examples from the subtropical Indian Ocean, western Mediterranean and Labrador Sea.

  11. Profiles

    International Nuclear Information System (INIS)

    2004-01-01

    Profiles is a synthetic overview of more than 100 national energy markets in the world, providing insightful facts and key energy statistics. A Profile is structured around 6 main items and completed by key statistics: Ministries, public agencies, energy policy are concerned; main companies in the oil, gas, electricity and coal sectors, status, shareholders; reserve, production, imports and exports, electricity and refining capacities; deregulation of prices, subsidies, taxes; consumption trends by sector, energy market shares; main energy projects, production and consumption prospects. Statistical Profiles are present in about 3 pages the main data and indicators on oil, gas, coal and electricity. (A.L.B.)

  12. Plankton Assemblage Estimated with BGC-Argo Floats in the Southern Ocean: Implications for Seasonal Successions and Particle Export

    Science.gov (United States)

    Rembauville, Mathieu; Briggs, Nathan; Ardyna, Mathieu; Uitz, Julia; Catala, Philippe; Penkerc'h, Cristophe; Poteau, Antoine; Claustre, Hervé; Blain, Stéphane

    2017-10-01

    The Southern Ocean (SO) hosts plankton communities that impact the biogeochemical cycles of the global ocean. However, weather conditions in the SO restrict mainly in situ observations of plankton communities to spring and summer, preventing the description of biological successions at an annual scale. Here, we use shipboard observations collected in the Indian sector of the SO to develop a multivariate relationship between physical and bio-optical data, and, the composition and carbon content of the plankton community. Then we apply this multivariate relationship to five biogeochemical Argo (BGC-Argo) floats deployed within the same bio-geographical zone as the ship-board observations to describe spatial and seasonal changes in plankton assemblage. The floats reveal a high contribution of bacteria below the mixed layer, an overall low abundance of picoplankton and a seasonal succession from nano- to microplankton during the spring bloom. Both naturally iron-fertilized waters downstream of the Crozet and Kerguelen Plateaus show elevated phytoplankton biomass in spring and summer but they differ by a nano- or microplankton dominance at Crozet and Kerguelen, respectively. The estimated plankton group successions appear consistent with independent estimations of particle diameter based on the optical signals. Furthermore, the comparison of the plankton community composition in the surface layer with the presence of large mesopelagic particles diagnosed by spikes of optical signals provides insight into the nature and temporal changes of ecological vectors that drive particle export. This study emphasizes the power of BGC-Argo floats for investigating important biogeochemical processes at high temporal and spatial resolution.

  13. Entropie analysis of floating car data systems

    Directory of Open Access Journals (Sweden)

    F. Gössel

    2004-01-01

    Full Text Available The knowledge of the actual traffic state is a basic prerequisite of modern traffic telematic systems. Floating Car Data (FCD systems are becoming more and more important for the provision of actual and reliable traffic data. In these systems the vehicle velocity is the original variable for the evaluation of the current traffic condition. As real FCDsystems are operating under conditions of limited transmission and processing capacity the analysis of the original variable vehicle speed is of special interest. Entropy considerations are especially useful for the deduction of fundamental restrictions and limitations. The paper analyses velocity-time profiles by means of information entropy. It emphasises in quantification of the information content of velocity-time profiles and the discussion of entropy dynamic in velocity-time profiles. Investigations are based on empirical data derived during field trials. The analysis of entropy dynamic is carried out in two different ways. On one hand velocity differences within a certain interval of time are used, on the other hand the transinformation between velocities in certain time distances was evaluated. One important result is an optimal sample-rate for the detection of velocity data in FCD-systems. The influence of spatial segmentation and of different states of traffic was discussed.

  14. Ranitidine Loaded Biopolymer Floats: Designing, Characterization, and Evaluation

    Directory of Open Access Journals (Sweden)

    Abdul Karim

    2017-01-01

    Full Text Available The float formulation is a strategy to improve the bioavailability of drugs by gastroretentive drug delivery system (GRDDS. A drug delivery model based on swellable and reswellable low density biopolymers has been designed to evaluate its drug release profile using ranitidine (RNT as a model drug and formulations have been prepared utilizing 32 factorial designs. The drug release (DR data has been subjected to various kinetic models to investigate the DR mechanism. A reduction in rate has been observed by expanding the amounts of PSG and LSG parts, while an expansion has been noted by increasing the concentration of tragacanth (TG and citric acid (CA with an increment in floating time. The stearic acid (SA has been used to decrease the lag time because a decrease in density of system was observed. The kinetic analysis showed that the optimized formulation (S4F3 followed zero-order kinetics and power law was found to be best fitted due to its minimum lag time and maximum floating ability. The resemblance of observed and predicted values indicated the validity of derived equations for evaluating the effect of independent variables while kinetic study demonstrated that the applied models are feasible for evaluating and developing float for RNT.

  15. Preparation and investigation of novel gastro-floating tablets with 3D extrusion-based printing.

    Science.gov (United States)

    Li, Qijun; Guan, Xiaoying; Cui, Mengsuo; Zhu, Zhihong; Chen, Kai; Wen, Haoyang; Jia, Danyang; Hou, Jian; Xu, Wenting; Yang, Xinggang; Pan, Weisan

    2018-01-15

    Three dimensional (3D) extrusion-based printing is a paste-based rapid prototyping process, which is capable of building complex 3D structures. The aim of this study was to explore the feasibility of 3D extrusion-based printing as a pharmaceutical manufacture technique for the fabrication of gastro-floating tablets. Novel low-density lattice internal structure gastro-floating tablets of dipyridamole were developed to prolong the gastric residence time in order to improve drug release rate and consequently, improve bioavailability and therapeutic efficacy. Excipients commonly employed in the pharmaceutical study could be efficiently applied in the room temperature 3D extrusion-based printing process. The tablets were designed with three kinds of infill percentage and prepared by hydroxypropyl methylcellulose (HPMC K4M) and hydroxypropyl methylcellulose (HPMC E15) as hydrophilic matrices and microcrystalline cellulose (MCC PH101) as extrusion molding agent. In vitro evaluation of the 3D printed gastro-floating tablets was performed by determining mechanical properties, content uniformity, and weight variation. Furthermore, re-floating ability, floating duration time, and drug release behavior were also evaluated. Dissolution profiles revealed the relationship between infill percentage and drug release behavior. The results of this study revealed the potential of 3D extrusion-based printing to fabricate gastro-floating tablets with more than 8h floating process with traditional pharmaceutical excipients and lattice internal structure design. Copyright © 2017. Published by Elsevier B.V.

  16. 14 CFR 29.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 29.753 Section 29.753... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure differential...

  17. 14 CFR 27.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 27.753 Section 27.753... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure differential...

  18. [Assessment of concomitant floating knees injuries severity].

    Science.gov (United States)

    Eone, Daniel Handy; Lamah, Léopold; Bayiha, Jean Emile; Ondoa, Danielle Larissa Essomba; Nonga, Bernadette Ngo; Ibrahima, Farikou; Bahebeck, Jean

    2016-01-01

    Floating knee is caused by high-energy trauma, whose genesis is suggestive of extensive locoregional and general damages. Referring to multiple trauma. The aim of our study was to collect data on all concomitant floating knee injuries in our practice environment and to evaluate their severity. We conducted a descriptive and retrospective study over a period of 14 years and 9 months. Our sample consisted of 75 floating knees, the average age was 35 years. Sixty six patients had an ISS≥16 (classified as polytrauma). Head traumas, chest and abdominal injuries associated with floating knee injuries require adequate resuscitation.

  19. Wave drag on floating bodies

    Science.gov (United States)

    Le Merrer, Marie; Clanet, Christophe; Quéré, David; Raphaël, Élie; Chevy, Frédéric

    2011-01-01

    We measure the deceleration of liquid nitrogen drops floating at the surface of a liquid bath. On water, the friction force is found to be about 10 to 100 times larger than on a solid substrate, which is shown to arise from wave resistance. We investigate the influence of the bath viscosity and show that the dissipation decreases as the viscosity is increased, owing to wave damping. The measured resistance is well predicted by a model imposing a vertical force (i.e., the drop weight) on a finite area, as long as the wake can be considered stationary. PMID:21876186

  20. Implementing floating-point DSP

    Czech Academy of Sciences Publication Activity Database

    Kadlec, Jiří; Chappel, S.

    2006-01-01

    Roč. 2, č. 3 (2006), s. 12-14 R&D Projects: GA AV ČR 1ET400750406; GA MŠk 1M0567 EU Projects: European Commission(XE) 027611 - AETHER Program:FP6 Institutional research plan: CEZ:AV0Z10750506 Keywords : PicoBlaze * floating point * FPGA Subject RIV: JC - Computer Hardware ; Software http://www.xilinx.com/publications/magazines/emb_03/xc_pdf/p12-14_3emb-point.pdf

  1. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  2. Nuclear floating power desalination complexes

    International Nuclear Information System (INIS)

    Panov, Y.K.; Polunichev, V.I.; Zverev, K.V.

    1998-01-01

    Russia is a single country in the world which possesses a powerful ice-breaker transport fleet that allows a solution of important social-economic tasks of the country's northern regions by maintaining a year-round navigation along the Arctic sea route. A total operating record of the marine nuclear reactors up until till now exceeds 150 reactor-years, with their main equipment operating life reacting 120 thousand hours. Design and constructional progresses have been made continuously during forty years of nuclear-powered ships construction in Russia. Well proven technology of all components experienced in the marine nuclear reactors give grounds to recommend marine NSSSs of KLT-40 type as energy sources for the heat and power co-generation plants and the sea water desalination complexes, particularly as a floating installation. Co-generation stations are considered for deployment in the extreme Northern Region of Russia. Nuclear floating desalination complexes can be used for drinkable water production in the coastal regions of Northern Africa, the Near East, India etc. (author)

  3. Novel Floating General Element Simulators Using CBTA

    Directory of Open Access Journals (Sweden)

    U. E. Ayten

    2012-04-01

    Full Text Available In this study, a novel floating frequency dependent negative resistor (FDNR, floating inductor, floating capacitor and floating resistor simulator circuit employing two CBTAs and three passive components is proposed. The presented circuit can realize floating FDNR, inductor, capacitor or resistor depending on the passive component selection. Since the passive elements are all grounded, this circuit is suitable for fully integrated circuit design. The circuit does not require any component matching conditions, and it has a good sensitivity performance with respect to tracking errors. Moreover, the proposed FDNR, inductance, capacitor and resistor simulator can be tuned electronically by changing the biasing current of the CBTA or can be controlled through the grounded resistor or capacitor. The high-order frequency dependent element simulator circuit is also presented. Depending on the passive component selection, it realizes high-order floating circuit defining as V(s = snAI(s or V(s = s-nBI(s. The proposed floating FDNR simulator circuit and floating high-order frequency dependent element simulator circuit are demonstrated by using PSPICE simulation for 0.25 μm, level 7, TSMC CMOS technology parameters.

  4. Formulation and Characterization of Sustained Release Floating ...

    African Journals Online (AJOL)

    Rouge N, Cale ET, Doelker E, Buri P. Buoyancy and drug release patterns of floating minitablets containing piretanide and atenolol as model drugs. Pharm. Dev. Technol. 1998; 3: 73-84. 6. Lee JH, Park TG, Choi HK. Development of oral drug delivery system using floating microspheres. J. Microencapsul. 1999; 16: 715-729 ...

  5. Vertical pump with free floating check valve

    International Nuclear Information System (INIS)

    Lindsay, M.

    1980-01-01

    A vertical pump is described which has a bottom discharge with a free floating check valve disposed in the outlet plenum thereof. The free floating check valve comprises a spherical member with a hemispherical cage-like member attached thereto which is capable of allowing forward or reverse flow under appropriate conditions while preventing reverse flow under inappropriate conditions

  6. Formulation of Nimesulide Floating Microparticles Using Low ...

    African Journals Online (AJOL)

    Nimesulide release was faster in simulated intestinal fluid (pH 6.8) than in simulated gastric fluid (pH 1.2) and distilled water (pH 6.5). Conclusion: Coacervation non-solvent addition is a suitable technique for preparing floating microparticles of nimesulide using low-viscosity HPMC. Keywords: Floating microparticles ...

  7. The night float paradigm to decrease sleep deprivation: good solution or a new problem?

    Science.gov (United States)

    Cavallo, Anita; Ris, M Douglas; Succop, Paul

    2003-06-10

    In the late 1980s physician residency training programs developed the night float rotation, characterized by a sequence of 5 - 15 days of night work without any daytime duties, thereby involving an abrupt reversal of the wake - sleep schedule. We examined the effect of the night float rotation on sleep, mood and performance of pediatric residents. Residents completed sleep diaries daily, and tests of mood (Profile of Mood States) and attention (Conner's Continuous Performance Test) three times a week during the two-week night float rotation, and during equivalent blocks of time of their daytime rotations. Results show that, despite having ample opportunity to sleep during the day, while on night float rotation residents slept less than during the nights of their normal daytime rotations, 6.3 h +/- 2.5 h and 7.2 h +/- 1.7 h, respectively, p inertia scores, 8.7 +/- 4.1 and 4.8 +/- 2.4, respectively, p < 0.0001, and decreased vigor-activity scores 10.7 +/- 5.4 and 14.8 +/- 5.3, respectively, p = 0.02. The scores for attention were not significantly different between night float and daytime rotations. The correlation coefficients of fatigue with measures of attention were not statistically significant for daytime rotations. However, for night float fatigue correlated with omission errors, r = 0.51, p = 0.001 and with attentiveness r = - 0.36, p = 0.03. Training programs that adopt the night float rotation must be aware of potential deleterious effects of the night float rotation as they may lead to serious consequences on residents' performance and patients' safety.

  8. Growing halophytes floating at sea

    Directory of Open Access Journals (Sweden)

    Ricardo Radulovich

    2017-11-01

    Full Text Available Freshwater shortages are increasingly limiting both irrigated and rainfed agriculture. To expand possibilities for controlled plant production without using land nor freshwater, we cultivated potted halophytes floating at sea that were provided with rain- and seawater. Plantlets of two mangroves (Avicennia germinans and Rhizophora mangle and plants of two herbaceous species, sea purslane (Sesuvium portulacastrum and salt couch grass (Sporobolus virginicus were grown in near-coastal tropical Pacific waters of Costa Rica for 733 days. There were a total of 504 rainless days, including two dry periods of ca. 150 d long each, evidencing prolonged and exclusive reliance on seawater. Pots with a sandy soil mixture and the transplanted plants were placed on low-cost wooden floating rafts with their lower end perforated and immersed for capillary rise of water. Free seawater entry and exit through the bottom from bobbing with waves, which also occasionally added water from the top, effectively controlled soil salinity build-up even during the rainless seasons. Continuous leaching made necessary frequent fertilizer addition. No water deficit symptoms were observed and midday canopy temperature during rainless periods was not significantly different between species or from air temperature. With all-year-round growth, height increase of mangrove plantlets ranged from 208.1 to 401.5 mm yr−1. Fresh biomass production of sea purslane and the grass was 10.9 and 3.0 kg m−2 yr−1 respectively. High yield, edibility and protein content of 10.2% dry weight established sea purslane as a potential crop. While further research is needed, the method evidenced to be a viable plant production option of potentially far-reaching applications.

  9. 14 CFR 23.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 23.753 Section 23.753... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Floats and Hulls § 23.753 Main float design. Each seaplane main float must meet the requirements of § 23.521. [Doc...

  10. Floating terminal as an alternative to shore terminals

    Energy Technology Data Exchange (ETDEWEB)

    Terenzio, M. [CoeClerici Logistics S.p.A. (Italy)

    2003-07-01

    Transfer vessels, floating terminals, catamaran type or Floating Transfer Stations (FTSs) are some of the latest alternative solutions to standard floating cranes. The CoeClerici 'Bulkwayuu' and 'Boca Grande' floating terminals are described and their advantages over shore-based structures are itemised. The text is accompanied by 17 overhead/slides. 1 fig.

  11. Cholecystosonographic findings of clonorchiasis: Floating echogenic foci

    International Nuclear Information System (INIS)

    Kim, Ho Kyun

    1989-01-01

    Author analysed cholecystosonographic findings in 22 patients with clonorchiasis, suspected prospectively by ultrasound and proved subsequently by demonstration of eggs in the stools. Fifteen gallbladders had nonshadowing, fusiform, discrete echogenic foci measuring 3∼6 mm in the lumen. Among these, the echogenic foci floated spontaneously in three cases, while in twelve cases they floated by position change or a light blow by the transducer. In the rest of the seven gallbladders, the echogenic foci were at the dependent portion. In the in vitro study with a worm suspension in saline in a surgical glove, the same echogenic foci as those seen in the gallbladders were demonstrated. The echogenic foci were precipitated in the dependent portion but float with a light blow on the glove. Author conclude that the floating echogenic foci in the lumen of the gallbladder are due to adult worms of clonorchis sinensis

  12. Dynamic Response of a Floating Bridge Structure

    OpenAIRE

    Viuff, Thomas; Leira, Bernt Johan; Øiseth, Ole; Xiang, Xu

    2016-01-01

    A theoretical overview of the stochastic dynamic analysis of a floating bridge structure is presented. Emphasis is on the wave-induced response and the waves on the sea surface are idealized as a zero mean stationary Gaussian process. The first-order wave load processes are derived using linear potential theory and the structural idealization is based on the Finite Element Method. A frequency response calculation is presented for a simplified floating bridge structure example emphasising the ...

  13. Sensitivity analysis of floating offshore wind farms

    International Nuclear Information System (INIS)

    Castro-Santos, Laura; Diaz-Casas, Vicente

    2015-01-01

    Highlights: • Develop a sensitivity analysis of a floating offshore wind farm. • Influence on the life-cycle costs involved in a floating offshore wind farm. • Influence on IRR, NPV, pay-back period, LCOE and cost of power. • Important variables: distance, wind resource, electric tariff, etc. • It helps to investors to take decisions in the future. - Abstract: The future of offshore wind energy will be in deep waters. In this context, the main objective of the present paper is to develop a sensitivity analysis of a floating offshore wind farm. It will show how much the output variables can vary when the input variables are changing. For this purpose two different scenarios will be taken into account: the life-cycle costs involved in a floating offshore wind farm (cost of conception and definition, cost of design and development, cost of manufacturing, cost of installation, cost of exploitation and cost of dismantling) and the most important economic indexes in terms of economic feasibility of a floating offshore wind farm (internal rate of return, net present value, discounted pay-back period, levelized cost of energy and cost of power). Results indicate that the most important variables in economic terms are the number of wind turbines and the distance from farm to shore in the costs’ scenario, and the wind scale parameter and the electric tariff for the economic indexes. This study will help investors to take into account these variables in the development of floating offshore wind farms in the future

  14. Preparation and Characterization of a Gastric Floating Dosage Form of Capecitabine

    Directory of Open Access Journals (Sweden)

    Ehsan Taghizadeh Davoudi

    2013-01-01

    Full Text Available Gastrointestinal disturbances, such as nausea and vomiting, are considered amongst the main adverse effects associated with oral anticancer drugs due to their fast release in the gastrointestinal tract (GIT. Sustained release formulations with proper release profiles can overcome some side effects of conventional formulations. The current study was designed to prepare sustained release tablets of Capecitabine, which is approved by the Food and Drug Administration (FDA for the treatment of advanced breast cancer, using hydroxypropyl methylcellulose (HPMC, carbomer934P, sodium alginate, and sodium bicarbonate. Tablets were prepared using the wet granulation method and characterized such that floating lag time, total floating time, hardness, friability, drug content, weight uniformity, and in vitro drug release were investigated. The sustained release tablets showed good hardness and passed the friability test. The tablets’ floating lag time was determined to be 30–200 seconds, and it floated more than 24 hours and released the drug for 24 hours. Then, the stability test was done and compared with the initial samples. In conclusion, by adjusting the right ratios of the excipients including release-retarding gel-forming polymers like HPMC K4M, Na alginate, carbomer934P, and sodium bicarbonate, sustained release Capecitabine floating tablet was formulated.

  15. Preparation and characterization of a gastric floating dosage form of capecitabine.

    Science.gov (United States)

    Taghizadeh Davoudi, Ehsan; Ibrahim Noordin, Mohamed; Kadivar, Ali; Kamalidehghan, Behnam; Farjam, Abdoreza Soleimani; Akbari Javar, Hamid

    2013-01-01

    Gastrointestinal disturbances, such as nausea and vomiting, are considered amongst the main adverse effects associated with oral anticancer drugs due to their fast release in the gastrointestinal tract (GIT). Sustained release formulations with proper release profiles can overcome some side effects of conventional formulations. The current study was designed to prepare sustained release tablets of Capecitabine, which is approved by the Food and Drug Administration (FDA) for the treatment of advanced breast cancer, using hydroxypropyl methylcellulose (HPMC), carbomer934P, sodium alginate, and sodium bicarbonate. Tablets were prepared using the wet granulation method and characterized such that floating lag time, total floating time, hardness, friability, drug content, weight uniformity, and in vitro drug release were investigated. The sustained release tablets showed good hardness and passed the friability test. The tablets' floating lag time was determined to be 30-200 seconds, and it floated more than 24 hours and released the drug for 24 hours. Then, the stability test was done and compared with the initial samples. In conclusion, by adjusting the right ratios of the excipients including release-retarding gel-forming polymers like HPMC K4M, Na alginate, carbomer934P, and sodium bicarbonate, sustained release Capecitabine floating tablet was formulated.

  16. Dispersion measurements from Sofar floats on the Iberian Abyssal plain

    International Nuclear Information System (INIS)

    Rees, J.M.; Gmitrowicz, M.

    1989-01-01

    Tracks of SOFAR floats launched on the Iberian Abyssal Plain are presented. The floats were launched in two groups in early October 1984 and mid-February 1985 to a nominal depth of 2500 m. Of these floats, 4 from the first deployment and 2 from the second functioned properly. Float signals were recorded by four autonomous listening stations at a depth of 1900 m. These preliminary results show the tracks of floats up to July 1986 and represent 3600 float days of information. The main task of the experiment was to especially study the dispersion of radioactive substances

  17. Coupled analysis of floating production systems

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, D.L. [Stress Engineering Services, Houston, TX (United States)

    2005-05-01

    Fully coupled global analysis of Floating Production Systems, including the vessel, the mooring system and the riser system is described. Design of the system can be a daunting task, involving more than 1000 load cases for global analysis. The primary driver for the mooring system and for the riser system is motion of the vessel. Vessel motions are driven by environmental forces, but are restrained by forces from the mooring and riser systems. Numerical models and procedures that provide accurate and efficient global modeling of the Floating Production System are presented. Both Time Domain and Frequency Domain procedures are included. The accuracy and efficiency of the procedures are illustrated in an example: a large semi with 16 mooring lines and 20 risers. The procedures provide the accuracy and efficiency for use of fully coupled analysis in design of Floating Production Systems from concept selection to final design, installation and operation. (Author)

  18. Raman scattering measurements on a floating water bridge

    Science.gov (United States)

    Ponterio, R. C.; Pochylski, M.; Aliotta, F.; Vasi, C.; Fontanella, M. E.; Saija, F.

    2010-05-01

    It was observed that when polarized by an intense electric field, water is able to self-arrange into macroscopic cylindrical wires that can hang up and remain floating against gravity. This phenomenon is now known as a 'water bridge'. Several attempts have been made to give an explanation of this apparently unusual behaviour of water. A number of experiments have been performed with the aim of probing any possible structural change of bulk water, after application of the electric field. None of the available findings appear conclusive at the moment. Here we report the results of the first Raman scattering experiment on floating water bridges. The inter-molecular OH-stretching band has been investigated and the results have been compared with those from bulk water. Some changes in the scattering profiles after application of the electric field are shown to have a structural origin. The bridges have been obtained, for the first time, in a vertical geometry and under application of an alternating field. The adopted geometry has allowed us to reveal a clear asymmetry between opposite direct current biasing, which can be related to the nature of the charge carriers.

  19. Raman scattering measurements on a floating water bridge

    International Nuclear Information System (INIS)

    Ponterio, R C; Aliotta, F; Vasi, C; Fontanella, M E; Saija, F; Pochylski, M

    2010-01-01

    It was observed that when polarized by an intense electric field, water is able to self-arrange into macroscopic cylindrical wires that can hang up and remain floating against gravity. This phenomenon is now known as a 'water bridge'. Several attempts have been made to give an explanation of this apparently unusual behaviour of water. A number of experiments have been performed with the aim of probing any possible structural change of bulk water, after application of the electric field. None of the available findings appear conclusive at the moment. Here we report the results of the first Raman scattering experiment on floating water bridges. The inter-molecular OH-stretching band has been investigated and the results have been compared with those from bulk water. Some changes in the scattering profiles after application of the electric field are shown to have a structural origin. The bridges have been obtained, for the first time, in a vertical geometry and under application of an alternating field. The adopted geometry has allowed us to reveal a clear asymmetry between opposite direct current biasing, which can be related to the nature of the charge carriers.

  20. Effects of Electrolyte on Floating Water Bridge

    OpenAIRE

    Hideo Nishiumi; Fumitaka Honda

    2009-01-01

    Fuchs found phenomena that when high voltage is applied to deionized water filled in two contacted beakers, a floating water bridge forms spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and N H 4 C l to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte A l 2 O 3 had no effect on the length of water bridge.

  1. Block floating point for radar data

    DEFF Research Database (Denmark)

    Christensen, Erik Lintz

    1999-01-01

    Integer, floating point, and block floating point (BFP) data formats are analyzed and compared in order to establish the mathematical tools for selection of an optimal format which fulfils the demands of high resolution radar (SAR) data to large dynamic range and adequate S/N. The analysis takes...... quantization noise and saturation distortion into account and concludes that it is preferred to use small blocks and a (new) modified BFP format applying fractional exponents. Data from the EMISAR radar system are applied to illustrate the merits of the different schemes....

  2. Floating plant can get uranium from seawater

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    A floating plant has been designed to extract uranium from seawater using solid adsorbents. Ore is removed from the adsorbent material by means of a solvent and concentrated in ion exchangers. Seawater is supplied to the adsorbent inside by wave energy and is based on the principle that waves will rush up a sloping plane that is partly submerged and fill a reservoir to a level higher than the still water level in the sea. The company projects that an offshore plant for recovering 600 tons of uranium/yr would comprise 22 floating concrete units, each measuring 430 x 75 meters

  3. Ge /Si heteronanocrystal floating gate memory

    Science.gov (United States)

    Li, Bei; Liu, Jianlin; Liu, G. F.; Yarmoff, J. A.

    2007-09-01

    Metal oxide semiconductor field effect transistor memories with Ge /Si heteronanocrystals (HNCs) as floating gate were fabricated and characterized. Ge /Si HNCs with density of 5×1011cm-2 were grown on n-type Si (100) substrate with thin tunnel oxide on the top. Enhanced device performances including longer retention time, faster programming speed, and higher charge storage capability are demonstrated compared with Si nanocrystal (NC) memories. The erasing speed and endurance performance of Ge /Si HNC memories are similar to that of Si NC devices. The results suggest that Ge /Si HNCs may be an alternative to make further floating gate memory scaling down possible.

  4. FLOAT2 WP4: Development of Materials

    DEFF Research Database (Denmark)

    Esteves, Luis Pedro; Aarup, Bendt

    This report refers to complementary material testing to support the design and production of UHPC floaters for installation in the Wave Star Machine under FLOAT2 project. The main objective of WP4 is the characterization of mechanical properties of fiber-reinforced UHPC.......This report refers to complementary material testing to support the design and production of UHPC floaters for installation in the Wave Star Machine under FLOAT2 project. The main objective of WP4 is the characterization of mechanical properties of fiber-reinforced UHPC....

  5. Floating Inductance and FDNR Using Positive Polarity Current Conveyors

    Directory of Open Access Journals (Sweden)

    K. Pal

    2004-01-01

    Full Text Available A generalized circuit based on five positive polarity second-generation current conveyors is introduced. The circuit simulates a floating inductance, capacitor floatation circuit and floating fdnr. All these circuits use grounded capacitors.

  6. 14 CFR 25.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 25.753 Section 25.753 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Floats and Hulls § 25.753 Main float design...

  7. associated injuries and complications in floating knee management

    African Journals Online (AJOL)

    Keywords: Associated injuries, complications, Floating knee, Management. INTRODUCTION. Floating knee refers to ipsilateral fractures of femur and tibia. Road accidents with high-energy trauma are the most frequent aetiology leading to that type of injury. In the management of floating knee, the lower limb deformation ...

  8. Validation of salinity data from ARGO floats: Comparison between the older ARGO floats and that of later deployments

    Digital Repository Service at National Institute of Oceanography (India)

    Youn, Y.-H.; Lee, H.; Chang, Y.-S.; Pankajakshan, T.

    Continued observation of ARGO floats or years (about 4 years) makes the conductivity sensor more vulnerable to fouling by marine life and associated drift in salinity measurements. In this paper, we address this issue by making use of floats...

  9. Finescale Water-Mass Variability from ARGO Profiling Floats

    Science.gov (United States)

    2015-09-30

    assessment of water-mass (aka thermohaline or spice) variability as a measure of stirring along isopycnals, as well as density ratio Rρ statistics, from the...Schmitt 1990) or double-diffusively-driven thermohaline interleaving. The coarse temporal and vertical sampling of the data are unlikely to allow...us to distinguish between these 2 mechanisms though persistent thermohaline intrusions spanning O(1000 km) have been reported in the equatorial

  10. A novel floating offshore wind turbine concept

    DEFF Research Database (Denmark)

    Vita, Luca; Schmidt Paulsen, Uwe; Friis Pedersen, Troels

    2009-01-01

    This paper will present a novel concept of a floating offshore wind turbine. The new concept is intended for vertical-axis wind turbine technology. The main purpose is to increase simplicity and to reduce total costs of an installed offshore wind farm. The concept is intended for deep water...

  11. Two New Families of Floating FDNR Circuits

    Directory of Open Access Journals (Sweden)

    Ahmed M. Soliman

    2010-01-01

    Full Text Available Two new configurations for realizing ideal floating frequency-dependent negative resistor elements (FDNR are introduced. The proposed circuits are symmetrical and are realizable by four CCII or ICCII or a combination of both. Each configuration is realizable by eight different circuits. Simulation results are included to support the theory.

  12. Floating Microparticulate Oral Diltiazem Hydrochloride Delivery ...

    African Journals Online (AJOL)

    Evaluation of micromeritic properties of floating microspheres. The microspheres were characterized for their micromeritic properties, such as particle size (by optical microscopy), true density (by liquid displacement method) and flow properties (angle of repose) as reported in various previous studies [17-19]. Drug loading.

  13. Near-Shore Floating Wave Energy Converters

    DEFF Research Database (Denmark)

    Ruol, Piero; Zanuttigh, Barbara; Martinelli, Luca

    2011-01-01

    Aim of this note is to analyse the possible application of a Wave Energy Converter (WEC) as a combined tool to protect the coast and harvest energy. Physical model tests are used to evaluate wave transmission past a near-shore floating WEC of the wave activated body type, named DEXA. Efficiency...

  14. Floating search methods in feature selection

    Czech Academy of Sciences Publication Activity Database

    Pudil, Pavel; Novovičová, Jana; Kittler, J.

    1994-01-01

    Roč. 15, - (1994), s. 1119-1125 ISSN 0167-8655 Grant - others:GA AV(CZ) A275107 Impact factor: 0.381, year: 1994 http://library.utia.cas.cz/separaty/historie/somol-floating search methods in feature selection.pdf

  15. Reis kosmosesse : [Floating-kambrist] / Marika Makarova

    Index Scriptorium Estoniae

    Makarova, Marika

    2011-01-01

    Ameerika psühholoogi John C. Lilly poolt kasutusele võetud Floating-kambrist ehk hõljumisvannist, mis aeglustab ajulaineid ning seeläbi aitab vähendada lihaspinget, stressi, ärevust, peavalusid, vererõhku ning parandada und, selgroo- ja kaelavigastusi, suurendada loovust ja heaolu jne

  16. Effects of Electrolyte on Floating Water Bridge

    Directory of Open Access Journals (Sweden)

    Hideo Nishiumi

    2009-01-01

    spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and NH4Cl to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte Al2O3 had no effect on the length of water bridge.

  17. Floating car data for traffic monitoring

    DEFF Research Database (Denmark)

    Torp, Kristian; Lahrmann, Harry Spaabæk

    2005-01-01

    This paper describes a complete prototype system that uses Floating Car Data (FCD) for both automatic and manual detection of queues in traffic. The system is developed under EU’s Tempo program. The systems consists of small hardware units placed in mobile traffic report units (we use taxis...

  18. IEEE Standard for Floating Point Numbers

    Indian Academy of Sciences (India)

    IAS Admin

    is to decide how to represent real numbers using these bits. Normally, in ... numbers explained above, the largest floating point number which can be represented is. The number of bits to be used for the mantissa is determined by the number of significant decimal .... This is used to give an error message. When an operation.

  19. Floating plant dominance as a stable state

    NARCIS (Netherlands)

    Scheffer, M.; Szabo, S.; Gragnani, A.; Nes, van E.H.; Rinaldi, S.; Kautsky, N.; Norberg, J.; Roijackers, R.M.M.; Franken, R.J.M.

    2003-01-01

    The authors demonstrate that floating-plant dominance can be a self-stabilizing ecosystem state, which may explain its notorious persistence in many situations. Their results, based on experiments, field data, and models (in Dutch ditches and Lake Kariba, Zimbabwe), represent evidence for

  20. Investigation on solar stills having floating plates

    Energy Technology Data Exchange (ETDEWEB)

    Panchal, Hitesh [KSV Univ., Gandhinagar Gujarat (India); Gujarat Power Engineering and Research Institute, Mehsana (India). Dept. of Mechanical Engineering; Shah, Pravin K. [Silver Oak College of Engineering and Technology, Ahmedabad, Gujarat (India)

    2012-07-01

    Potable water is always a need of every human being in the world. Only one third of water is potable water and two third of water is saline water, which is not used for drinking purpose. Solar still is a device, which converts the saline or brackish water into drinkable water. Here, in place of saline water, industrial waste water is used to convert potable water. In this research work, three solar stills have developed by locally available materials and tested in climate conditions of Mehsana (latitude of 23 59' and the longitude of 72 38'). Among three solar stills, two solar stills consist of Floating plates like Aluminum and galvanized iron. Third solar still used as a reference solar still called conventional solar still. Three month research showed that, solar still consist of Aluminum floating plate, gave considerable daily distillate as well as cumulative output compared with galvanized Iron floating plate solar still as well as conventional solar still Hence, performance of solar still could be increase by use of Aluminum Floating plate, which can use as a energy absorbing plate. (orig.)

  1. IEEE Standard for Floating Point Numbers

    Indian Academy of Sciences (India)

    IAS Admin

    This is a conservative definition used by industry. In MATLAB, machine epsilon is as defined above. However, academics define machine epsilon as the upper bound of the relative error when numbers are rounded. Thus, for 32-bit floating point numbers, the machine epsilon is 2–23/2. 5.96 ×10–8. The machine epsilon is ...

  2. Phytophilous Macroinvertebrates of Floating Nymphaea lotus and ...

    African Journals Online (AJOL)

    Phytophilous macroinvertebrates associated with two dominant floating aquatic macrophytes, water lilly (Nymphaea lotus) and water lettuce (Pistia stratiotes) in River Orogodo, Niger Delta were sampled between February and July 2006. The location of both plant species exhibited similar water quality characteristics during ...

  3. Floating-Emitter Solar-Cell Transistor

    Science.gov (United States)

    Sah, C. T.; Cheng, L. J.

    1986-01-01

    Conceptual transistor embedded in photovoltaic diode promises to increase efficiency to more than 20 percent. Solar-cell transistor has front-surface contact, rear contact, and floating emitter. Variety of other contact and junction configurations possible, but do not offer ease of fabrication in combination with high performance.

  4. Dealing with Human Death: The Floating Perspective.

    Science.gov (United States)

    Kenyon, Gary M.

    1991-01-01

    Explores approach to dealing with human death. Describes floating perspective, based on insights from Choron and Jaspers, as suggesting it is possible to deal with human death by refraining from taking ultimate position on the problem. Position encourages openness to death. Examines role of anxiety and describes possible meaningful outcomes of…

  5. Gastroretentive Floating Microspheres of Silymarin: Preparation and ...

    African Journals Online (AJOL)

    Methods: Cellulose microspheres – formulated with hydroxylpropyl methylcellulose (HPMC) and ethyl cellulose (EC) – and Eudragit microspheres – formulated with Eudragit® S 100 (ES) and Eudragit® RL (ERL) - were prepared by an emulsion-solvent evaporation method. The floating microspheres were evaluated for flow ...

  6. IEEE Standard for Floating Point Numbers

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 1. IEEE Standard for Floating Point Numbers. V Rajaraman. General Article Volume 21 Issue 1 January 2016 pp 11-30. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/021/01/0011-0030. Keywords.

  7. Development of floating strip micromegas detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bortfeldt, Jonathan

    2014-04-28

    Micromegas are high-rate capable, high-resolution micro-pattern gaseous detectors. Square meter sized resistive strip Micromegas are foreseen as replacement of the currently used precision tracking detectors in the Small Wheel, which is part of the forward region of the ATLAS muon spectrometer. The replacement is necessary to ensure tracking and triggering performance of the muon spectrometer after the luminosity increase of the Large Hadron Collider beyond its design value of 10{sup 34} cm{sup -2}s{sup -1} around 2020. In this thesis a novel discharge tolerant floating strip Micromegas detector is presented and described. By individually powering copper anode strips, the effects of a discharge are confined to a small region of the detector. This reduces the impact of discharges on the efficiency by three orders of magnitude, compared to a standard Micromegas. The physics of the detector is studied and discussed in detail. Several detectors are developed: A 6.4 x 6.4 cm{sup 2} floating strip Micromegas with exchangeable SMD capacitors and resistors allows for an optimization of the floating strip principle. The discharge behavior is investigated on this device in depth. The microscopic structure of discharges is quantitatively explained by a detailed detector simulation. A 48 x 50 cm{sup 2} floating strip Micromegas is studied in high energy pion beams. Its homogeneity with respect to pulse height, efficiency and spatial resolution is investigated. The good performance in high-rate background environments is demonstrated in cosmic muon tracking measurements with a 6.4 x 6.4 cm{sup 2} floating strip Micromegas under lateral irradiation with 550 kHz 20 MeV proton beams. A floating strip Micromegas doublet with low material budget is developed for ion tracking without limitations from multiple scattering in imaging applications during medical ion therapy. Highly efficient tracking of 20 MeV protons at particle rates of 550 kHz is possible. The reconstruction of the

  8. Seven centuries of atmospheric Pb deposition recorded in a floating mire from Central Italy

    Science.gov (United States)

    Zaccone, Claudio; Lobianco, Daniela; D'Orazio, Valeria; Miano, Teodoro M.; Shotyk, William

    2016-04-01

    Floating mires generally consist of emergent vegetation rooted in highly organic buoyant mats that rise and fall with changes in water level. Generally speaking, the entire floating mass (mat) is divided into a mat root zone and an underlying mat peat zone. Floating mires are distributed world-wide; large areas of floating marsh occur along rivers and lakes in Africa, the Danube Delta in Romania, the Amazon River in South America, and in the Mississippi River delta in USA, whereas smaller areas occur also in The Netherlands, Australia and Canada. While peat cores from ombrotrophic bogs have been often (and successfully) used to reconstruct changes in the atmospheric deposition of several metals (including Pb), no studies are present in literature about the possibility to use peat profiles from floating mires. To test the hypothesis that peat-forming floating mires could provide an exceptional tool for environmental studies, a complete, 4-m deep peat profile was collected in July 2012 from the floating island of Posta Fibreno, a relic mire in the Central Italy. This floating island has a diameter of ca. 30 m, a submerged thickness of about 3 m, and the vegetation is organized in concentric belts, from the Carex paniculata palisade to the Sphagnum palustre centre. The whole core was frozen cut each 1-to-2 cm (n =231), and Pb determined by quadrupole ICP-MS (at the ultraclean SWAMP lab, University of Alberta, Canada) in each sample throughout the first 100 cm, and in each odd-numbered slice for the remaining 300 cm. The 14C age dating of organic sediments (silty peat) isolated from the sample at 385 cm of depth revealed that the island probably formed ca. 700 yrs ago. Lead concentration trend shows at least two main zones of interest, i.e., a clear peak (ranging from 200 to 1600 ppm) between 110-115 cm of depth, probably corresponding to early 1960's - late 1970's, and a broad band (80-160 ppm) between 295-320 cm of depth, corresponding to approximately AD 1480

  9. Floating matrix dosage form for propranolol hydrochloride based on gas formation technique: development and in vitro evaluation.

    Science.gov (United States)

    Chaturvedi, Kiran; Umadevi, S; Vaghani, Subhash

    2010-01-01

    Gastroretentive tablets of propranolol hydrochloride were developed by direct compression method using citric acid and sodium bicarbonate as the effervescent base. Hydroxypropyl methylcellulose; HPMC K15M was used to prepare the floating tablets to retard the drug release for 12h in stomach. Na-carboxymethyl cellulose (NaCMC) or carbopol 934P was added to alter the drug release profile or the dimensional stability of the formulation. Dicalcium phosphate (DCP) was used as filler. Formulations were evaluated for floating lag time, duration of floating, dimensional stability, drug content and in vitro drug release profile. The formulations were found to have floating lag time less than 1min. It was found that the dimensional stability of the formulations increase with increasing concentration of the swelling agent. The release mechanism of propranolol hydrochloride from floating tablets was evaluated on the basis of Peppas and Higuchi model. The ânâ value of the formulations ranged from 0.5201 to 0.7367 (0.5citric acid and 18.75% sodium bicarbonate seemed most desirable. FTIR, DSC and XRPD studies indicated the absence of any significant chemical interaction within dug and excipients. Stability study of optimized formulation revealed no significant change and found to be stable.

  10. Preparation and statistical optimization of alginate based stomach specific floating microcapsules of simvastatin.

    Science.gov (United States)

    Premchandani, Tushar A; Barik, Bhakti B

    2012-01-01

    The present study involves preparation and characterization of floating microcapsules with simvastatin as model drug for prolongation of gastric residence time. The main objective is to improve solubility of simvastatin beta-CD complex (1:2) by co-precipitation method and then to deliver the same in sustained release dosage form. Sustained-release simvastatin microcapsules were prepared by the ionic gelation technique, using carbopol 941 as swellable floating polymer. A 3(3) full factorial design was used to study the effect of polymer concentration, drug complex and sodium alginate by plotting main effect plot and 3D surface plots. The formed microcapsules were subjected to various evaluation tests such as drug encapsulation efficiency, in vitro drug release and surface morphology by scanning electron microscopy. Powdered X-ray diffractometry and FTIR were used to investigate the complexation of simvastatin in the microcapsules. As the carbopol 941 is self swellable polymer, immediate floating was observed. The in vitro release studies and floating behavior were performed in HCI buffer of pH 1.2. The release profile and dissolution kinetic showed that drug release from the microcapsules follows zero order kinetics. It was concluded from the present investigation that porous carbopol 941 microcapsules are promising sustained release system as well as stomach specific carriers for delivery of simvastatin.

  11. Voltage-Controlled Floating Resistor Using DDCC

    Directory of Open Access Journals (Sweden)

    M. Kumngern

    2011-04-01

    Full Text Available This paper presents a new simple configuration to realize the voltage-controlled floating resistor, which is suitable for integrated circuit implementation. The proposed resistor is composed of three main components: MOS transistor operating in the non-saturation region, DDCC, and MOS voltage divider. The MOS transistor operating in the non-saturation region is used to configure a floating linear resistor. The DDCC and the MOS transistor voltage divider are used for canceling the nonlinear component term of MOS transistor in the non-saturation region to obtain a linear current/voltage relationship. The DDCC is employed to provide a simple summer of the circuit. This circuit offers an ease for realizing the voltage divider circuit and the temperature effect that includes in term of threshold voltage can be compensated. The proposed configuration employs only 16 MOS transistors. The performances of the proposed circuit are simulated with PSPICE to confirm the presented theory.

  12. Floating platform for offshore hydrocarbon production

    Energy Technology Data Exchange (ETDEWEB)

    Waddell, J.W.

    1994-07-27

    A floating platform comprises a vessel having a deck or topsides portion mounted above the highest expected water level at the site where the platform is to be located, and a tension moored wellhead/manifold assembly secured to the seabed by at least two tethers against the action of its own buoyancy and floating below the water surface at a predetermined height above the seabed, the arrangement being such that the vessel can be positioned directly over the tension moored wellhead/manifold assembly and can draw oil and/or gas from risers and/or conductors terminating in that assembly for processing and export via the deck or topsides. The vessel may be fixed in position by catenary anchors or tension legs. (Author)

  13. Fresh water generators onboard a floating platform

    International Nuclear Information System (INIS)

    Tewari, P.K.; Verma, R.K.; Misra, B.M.; Sadhulkan, H.K.

    1997-01-01

    A dependable supply of fresh water is essential for any ocean going vessel. The operating and maintenance personnel on offshore platforms and marine structures also require a constant and regular supply of fresh water to meet their essential daily needs. A seawater thermal desalination unit onboard delivers good quality fresh water from seawater. The desalination units developed by Bhabha Atomic Research Centre (BARC) suitable for ocean going vessels and offshore platforms have been discussed. Design considerations of such units with reference to floating platforms and corrosive environments have been presented. The feasibility of coupling a low temperature vacuum evaporation (LTVE) desalination plant suitable for an onboard floating platform to a PHWR nuclear power plant has also been discussed. (author). 1 ref., 3 figs, 2 tabs

  14. Adaptive floating search methods in feature selection

    Czech Academy of Sciences Publication Activity Database

    Somol, Petr; Pudil, Pavel; Novovičová, Jana; Paclík, Pavel

    1999-01-01

    Roč. 20, 11/13 (1999), s. 1157-1163 ISSN 0167-8655 R&D Projects: GA ČR GA402/97/1242 Grant - others:MŠMT(CZ) VS96063 Institutional research plan: AV0Z1075907 Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.315, year: 1999 http://library.utia.cas.cz/separaty/historie/somol-adaptive floating search methods in feature selection.pdf

  15. Floating nuclear power plant safety assurance principles

    International Nuclear Information System (INIS)

    Zvonarev, B.M.; Kuchin, N.L.; Sergeev, I.V.

    1993-01-01

    In the north regions of the Russian federation and low density population areas, there is a real necessity for ecological clean energy small power sources. For this purpose, floating nuclear power plants, designed on the basis of atomic ship building engineering, are being conceptualized. It is possible to use the ship building plants for the reactor purposes. Issues such as radioactive waste management are described

  16. Near-diffraction-limited and low-haze electro-optical tunable liquid crystal lens with floating electrodes.

    Science.gov (United States)

    Li, Liwei; Bryant, Doug; Van Heugten, Tony; Bos, Philip J

    2013-04-08

    A near-diffraction-limited, low-haze and tunable liquid crystal (LC) lens is presented. Building on an understanding of the key factors that have limited the performance of lenses based on liquid crystals, we show a simple design whose optical quality is similar to a high quality glass lens. It uses 'floating' electrodes to provide a smooth, controllable applied potential profile across the aperture to manage the phase profile.

  17. Floating debris in the Mediterranean Sea.

    Science.gov (United States)

    Suaria, Giuseppe; Aliani, Stefano

    2014-09-15

    Results from the first large-scale survey of floating natural (NMD) and anthropogenic (AMD) debris (>2 cm) in the central and western part of the Mediterranean Sea are reported. Floating debris was found throughout the entire study area with densities ranging from 0 to 194.6 items/km(2) and mean abundances of 24.9 AMD items/km(2) and 6.9 NMD items/km(2) across all surveyed locations. On the whole, 78% of all sighted objects were of anthropogenic origin, 95.6% of which were petrochemical derivatives (i.e. plastic and styrofoam). Maximum AMD densities (>52 items/km(2)) were found in the Adriatic Sea and in the Algerian basin, while the lowest densities (<6.3 items/km(2)) were observed in the Central Tyrrhenian and in the Sicilian Sea. All the other areas had mean densities ranging from 10.9 to 30.7 items/km(2). According to our calculations, more than 62 million macro-litter items are currently floating on the surface of the whole Mediterranean basin. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Mesoscale variability of water masses in the Arabian Sea as revealed by ARGO floats

    Directory of Open Access Journals (Sweden)

    X. Carton

    2012-03-01

    Full Text Available By analysing ARGO float data over the last four years, a few aspects of the mesoscale variability of water masses in the Arabian Sea are described.

    The Red Sea Outflow Water (RSOW is concentrated in the Southwestern Gulf of Aden, in particular when a cyclonic gyre predominates in this region. Salinities of 36.5 and temperatures of 16 °C are found in this area at depths between 600 and 1000 m. RSOW is more dilute in the eastern part of the Gulf, where intense and relatively barotropic gyres mix it with Indian ocean Central Water. RSOW is also detected along the northeastern coast of Socotra, and fragments of RSOW are found between one and three degrees of latitude north of this island. In the whole Gulf of Aden, the correlation between the deep motions of the floats and the sea-level anomaly measured by altimetry is strong, at regional scale. The finer scale details of the float trajectories are not sampled by altimetry and are often related to the anomalous water masses that the floats encounter.

    The Persian Gulf Water (PGW is found in the float profiles near Ras ash Sharbatat (near 57° E, 18° N, again with 36.5 in salinity and about 18–19 °C in temperature. These observations were achieved in winter when the southwestward monsoon currents can advect PGW along the South Arabian coast. Fragments of PGW were also observed in the Arabian Sea between 18 and 20° N and 63 and 65° E in summer, showing that this water mass can escape the Gulf of Oman southeastward, during that season.

    Kinetic energy distributions of floats with respect to distance or angle share common features between the two regions (Gulf of Aden and Arabian Sea, in particular peaks at 30, 50 and 150 km scales and along the axis of monsoon currents. Hydrological measurements by floats are also influenced by the seasonal variations of PGW and RSOW in these regions.

  19. Cefuroxime axetil loaded gastroretentive floating tabletsbased on hydrophilic polymers: preparation and in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Snehamayee Mohapatra

    2012-04-01

    Full Text Available The aim of this work was to study the formulation and in vitro characterization of hydro dynamically balanced floating matrix tablets using Cefuroxime axetil (CA as model drug. Different excipients such as hydroxy propyl methyl cellulose (HPMC K15M, E5LV (gelling agent, sodium bicarbonate (gas generating agent and sodium lauryl sulfate (SLS (solubility enhancer were used in order to optimize the drug release profile as well as floating property. Decrease in release characteristics with high viscous polymer were observed due to increased gel strength, tortuosity and length of drug diffusion path. Significant difference (p<0.5 in release rate was found at different concentration of SLS. The release mechanisms were explored and explained with zero order, first order, Higuchi, Korsmeyer and Hixson-Crowell equations. The release rate, extent and mechanism were governed by the content of polymer. The polymer content and amount of floating agent significantly affected the time required for 50%of drug release (t50%, mean dissolution time (MDT, release rate constant, and diffusion exponent (n.Kinetic modeling of dissolution profile revealed that the drug release mechanism could range from diffusion controlled to case II transport, which was co-dominated by diffusion polymer erosion in the release mechanism.

  20. On seismic response characteristics of floating nuclear plant barge, (1)

    International Nuclear Information System (INIS)

    Hagiwara, Yutaka; Masuko, Yoshio; Nakamura, Shuuji; Matsuura, Shinichi; Shiojiri, Hiroo

    1986-01-01

    Since Floating Nuclear Plants (FNP) are considered to be isolated from horizontal seismic motion, reduction and standardization of the aseismic design conditions of the floating plants are anticipated. However, studies on FNP in closed and shallow basin have almost not been executed to data, and there are many problems remaining unsolved. The purpose of the present report is to obtain sufficient elementary data and materials on the seismic response of floating body in the closed and shallow basin. Some interesting points to be extracted from shaking table tests, finite element analyses and simplified analyses are summarized as follows: 1) The seismic isolation characteristics of the floating body are remarkable to short period horizontal seismic motion. 2) Resonances of the floating body's motion, which coupled with surface waves, are induced by long period horizontal seismic motion. 3) Vertical seismic motion is transmitted directly to the floating body. (author)

  1. Investigation of Tank 241-AW-104 Composite Floating Layer

    Energy Technology Data Exchange (ETDEWEB)

    Meznarich, H. K. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States); Bolling, S. D. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States); Lachut, J. S. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States); Cooke, G. A. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States)

    2018-02-27

    Seven grab samples and one field blank were taken from Tank 241-AW-104 (AW-104) on June 2, 2017, and received at 222-S Laboratory on June 5, 2017. A visible layer with brown solids was observed floating on the top of two surface tank waste samples (4AW-17-02 and 4AW 17 02DUP). The floating layer from both samples was collected, composited, and submitted for chemical analyses and solid phase characterization in order to understand the composition of the floating layer. Tributyl phosphate and tridecane were higher in the floating layer than in the aqueous phase. Density in the floating layer was slightly lower than the mean density of all grab samples. Sodium nitrate and sodium carbonate were major components with a trace of gibbsite and very small size agglomerates were present in the solids of the floating layer. The supernate consisted of organics, soluble salt, and particulates.

  2. Soil hypoxia induced by an organic-material mulching technique stimulates the bamboo rhizome up-floating of Phyllostachys praecox.

    Science.gov (United States)

    Xu, Mengjie; Zhuang, Shunyao; Gui, Renyi

    2017-10-30

    Phyllostachys praecox bamboo stands significantly recede after 3 or 4 years using an organic-material mulching technique consecutively. We hypothesized that the bamboo recession is caused by the up-floating of underground rhizome stimulated by soil hypoxia through the mulching technique. This study aimed to validate this hypothesis by field investigation. Bamboo underground rhizome distribution in the soil profile of P. praecox subjected to various mulching times was investigated. Results showed that bamboo rhizome weights and lengths increased with increased mulching time. However, after 4 years of mulching, the number of fresh rhizomes decreased significantly, and more than 50% of rhizomes floated upward to the shallow soil layer (0-10 cm). Moreover, the 0-10 cm soil layer suffered severe acidification that severely impeded bamboo-rhizome growth. The soil hypoxia induced by the mulching technique must be responsible for the bamboo rhizome up-floating. We confirmed that bamboo rhizome up-floating was the critical factor that caused the bamboo growth to recede under the mulching technique. Therefore, managing this bamboo rhizome up-floating is the key to sustainable bamboo production. The effect of soil hypoxia in the absence of flooding or waterlogging on plant root growth also warrants further and extensive study.

  3. The floating knee: epidemiology, prognostic indicators & outcome following surgical management

    OpenAIRE

    Yesupalan Rajam S; Rethnam Ulfin; Nair Rajagopalan

    2007-01-01

    Abstract Background Floating Knee injuries are complex injuries. The type of fractures, soft tissue and associated injuries make this a challenging problem to manage. We present the outcome of these injuries after surgical management. Methods 29 patients with floating knee injuries were managed over a 3 year period. This was a prospective study were both fractures of the floating knee injury were surgically fixed using different modalities. The associated injuries were managed appropriately. ...

  4. Finite element simulation of long wave impact on floating breakwaters with variable stiffness

    Science.gov (United States)

    Papathanasiou, T. K.; Karperaki, A.; Belibassakis, K. A.

    2017-12-01

    The hydroelastic response of flexible, floating breakwaters is a subject of interest for coastal engineering applications. In this study, a higher order hydroelastic finite element is applied to the simulation of floating breakwaters of variable stiffness undergoing long wave impact. The main aim is the evaluation of breakwater efficiency in terms of transmitted and reflected wave characteristics. It is established that, for the wave-lengths examined, the maximum amplitude and wave-length of the transmitted pulse are strongly dependent on the breakwater stiffness. Finally it is shown that for case of a periodic stiffness profile the transmitted energy is minimised when the modulation wavelength is comparable to the wavelength of the incoming excitation.

  5. Stress analysis and mitigation measures for floating pipeline

    Science.gov (United States)

    Wenpeng, Guo; Yuqing, Liu; Chao, Li

    2017-03-01

    Pipeline-floating is a kind of accident with contingency and uncertainty associated to natural gas pipeline occurring during rainy season, which is significantly harmful to the safety of pipeline. Treatment measures against pipeline floating accident are summarized in this paper on the basis of practical project cases. Stress states of pipeline upon floating are analyzed by means of Finite Element Calculation method. The effectiveness of prevention ways and subsequent mitigation measures upon pipeline-floating are verified for giving guidance to the mitigation of such accidents.

  6. Advantages of floating covers with LLDPE Liners

    International Nuclear Information System (INIS)

    Munoz Gomez, J. M.

    2014-01-01

    Using floating covers in irrigation pounds and waste dam gives many advantages. It is a very interesting investment for those place with a high evaporation ratio. this is an easy system which improves several aspects in irrigation or drinkable water reservoirs, mainly it saves water and it saves clean-works (time and cost). It is also used in waste dam to deodorization. Time ago this application was developed with PVC liners and TPO liners, now the innovation is LLDPE liners which improve mechanical properties, durability and an easier installation. This paper develops the state of art of this design technology, and the back ground of our experience. (Author)

  7. Experiments in a floating water bridge

    Science.gov (United States)

    Woisetschläger, Jakob; Gatterer, Karl; Fuchs, Elmar C.

    2010-01-01

    In a high-voltage direct-current experiment, a watery connection formed between two beakers filled with deionized water, giving the impression of a `floating water bridge'. Having a few millimeters diameter and up to 2.5 cm length, this watery connection reveals a number of interesting phenomena currently discussed in water science. Focusing on optical measurement techniques, the flow through the bridge was visualized and data were recorded such as flow velocity and directions, heat production, density fluctuations, pH values, drag force and mass transfer. To provide a better understanding of the basic phenomena involved the discussion references related literature.

  8. Dynamics of the floating water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Gatterer, Karl; Holler, Gert; Woisetschlaeger, Jakob

    2008-01-01

    When high voltage is applied to distilled water filled into two beakers close to each other, a water connection forms spontaneously, giving the impression of a floating water bridge (Fuchs et al 2007 J. Phys. D: Appl. Phys. 40 6112-4). This phenomenon is of special interest, since it comprises a number of phenomena currently tackled in modern water science. The build-up mechanism, the chemical properties and the dynamics of this bridge as well as related additional phenomena are presented and discussed

  9. Floating / Travelling Gardens of (Postcolonial Time

    Directory of Open Access Journals (Sweden)

    Carmen Concilio

    2017-11-01

    Full Text Available This essay on travelling gardens of (postcolonial time opens with two iconic images of floating gardens in contemporary postcolonial literature: Will Phantom’s bio-garbage rafter, which saves him in the midst of a cyclone in Carpentaria (2008, by the Aboriginal author Alexis Wright, and Pi’s carnivore island-organism in Life of Pi (2001, which cannot save him from his shipwreck, by Canadian writer Yan Martel. These floating, hybrid gardens of the Anthropocene precede the real travelling gardens of both Michael Ondaatje’s The Cat’s Table (2011 and Amitav Ghosh’s Ibis Trilogy (2008-2015, two authors who both indirectly and directly tell the story of botanical gardens in Asia, and of plant and seed smuggling and transplantation (“displacement” also hinting at their historical and economic colonial implications. For, after all, botanical gardens imply a very specific version of care, Cura (Robert Pogue Harrison 2009, while embodying a precise, imperial scientific and economic project (Brockway 2002; Johnson 2011.

  10. Water-Pressure Distribution on Seaplane Float

    Science.gov (United States)

    Thompson, F L

    1929-01-01

    The investigation presented in this report was conducted for the purpose of determining the distribution and magnitude of water pressures likely to be experienced on seaplane hulls in service. It consisted of the development and construction of apparatus for recording water pressures lasting one one-hundredth second or longer and of flight tests to determine the water pressures on a UO-1 seaplane float under various conditions of taxiing, taking off, and landing. The apparatus developed was found to operate with satisfactory accuracy and is suitable for flight tests on other seaplanes. The tests on the UO-1 showed that maximum pressures of about 6.5 pounds per square inch occur at the step for the full width of the float bottom. Proceeding forward from the step the maximum pressures decrease in magnitude uniformly toward the bow, and the region of highest pressures narrows toward the keel. Immediately abaft the step the maximum pressures are very small, but increase in magnitude toward the stern and there once reached a value of about 5 pounds per square inch. (author)

  11. Feasibility study on floating nuclear power station

    International Nuclear Information System (INIS)

    Kajima, Ryoichi

    1987-01-01

    It is stipulated that nuclear power plants are to be built on solid rock bases on land in Japan. However, there are a limited number of appropriate siting grounds. The Central Research Institute of Electric Power Industry has engaged since 1981 in the studies on the construction technology of power plants, aiming at establishing new siting technology to expand the possible siting areas for nuclear power plants. Underground siting is regarded as a proven technology due to the experience in underground hydroelectric power plants. The technology of siting on quaternary ground is now at the stage of verification. In this report, the outline of floating type offshore/inshore siting technology is introduced, which is considered to be feasible in view of the technical and economical aspects. Three fixed structure types were selected, of which the foundations are fixed to seabed, plant superstructures are above sea surface, and which are floating type. Aiming at ensuring the aseismatic stability of the plant foundations, the construction technology is studied, and the structural concept omitting buoyancy is possible. The most practical water depth is not more than 20 m. The overall plant design, earthquake isolation effect and breakwater are described. (Kako, I.)

  12. Characterization of the bio-optical anomaly and diurnal variability of particulate matter, as seen from scattering and backscattering coefficients, in ultra-oligotrophic eddies of the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    H. Loisel

    2011-11-01

    Full Text Available The variability of inherent optical properties is investigated in the ultra-oligotrophic waters of the Mediterranean Sea sampled during the BOUM experiment performed during early summer 2008. Bio-optical relationships found for ultra-oligotrophic waters of the three anticyclonic gyres sampled significantly depart from the mean standard relationships provided for the global ocean, confirming the peculiar character of these Mediterranean waters. These optical anomalies are diversely related to the specific biological and environmental conditions occurring in the studied ecosystem. Specifically, the surface specific phytoplankton absorption coefficient exhibits values lower than those expected from the general relationships mainly in relation with a high contribution of relatively large sized phytoplankton. Conversely, the particulate backscattering coefficient, bbp, values are much higher than the mean standard values for a given chlorophyll-a concentration, TChl-a. This feature can presumably be related to the relevant influence of highly refractive submicrometer particles of Saharan origin in the surface layer of the water column. The present measurements also show that the Mediterranean Sea is greener than TChl-a alone indicates, as already stressed in previous studies. This color anomaly is partly explained by the estimated colored dissolved organic matter and submicrometer particles absorption coefficients, and to a greater extent by the high bbp/TChl-a values assuming that these particles backscatter light similarly in the green and blue parts of the visible spectrum. The diel variation of both the particulate matter attenuation and backscattering coefficients were also investigated specifically. Despite some differences in the timing and the magnitude of the daily oscillations found for these optical parameters, potential for the backscattering coefficient daily oscillation to

  13. Formulation and Evaluation of Gastro Retentive Floating Drug ...

    African Journals Online (AJOL)

    The aim of the present investigation is to develop and optimize gastroretentive floating drug delivery systems for propranolol HCl. Propranolol HCl is an effective anti hypertensive drug, with a relatively short half life and is freely soluble in water. In the present work, propranolol HCl floating tablets were prepared with PEO ...

  14. Response estimation for a floating bridge using acceleration output only

    NARCIS (Netherlands)

    Petersen, Øyvind Wiig; Øiseth, Ole; Nord, Torodd Skjerve; Lourens, E.; Sas, P.; Moens, D.; van de Walle, A.

    2016-01-01

    The Norwegian Public Roads Administration is reviewing the possibility of using floating bridges as fjord crossings. The dynamic behaviour of very long floating bridges with novel designs are prone to uncertainties. Studying the dynamic behaviour of existing bridges is valuable for understanding

  15. Development and evaluation of floating microspheres of curcumin in ...

    African Journals Online (AJOL)

    Purpose: To prepare and evaluate floating microspheres of curcumin for prolonged gastric residence and to study their effect on alloxan-induced diabetic rats. Methods: Floating microsphere were prepared by emulsion-solvent diffusion method, using hydroxylpropyl methylcellulose, chitosan and Eudragit S 100 polymer in ...

  16. Development and Evaluation of Floating Microspheres of Curcumin ...

    African Journals Online (AJOL)

    Purpose: To prepare and evaluate floating microspheres of curcumin for prolonged gastric residence time and increased drug bioavailability. Methods: Floating microsphere were prepared by emulsion solvent diffusion method, using hydroxylpropyl methylcellulose (HPMC), ethyl cellulose (EC), Eudragit S 100 polymer in ...

  17. C/O logging neutron generator with floating power supply

    CERN Document Server

    Jiang Zhon Gjin; Li Wen Sheng; Guo Jing Fu; Wei Bao Jie

    2002-01-01

    Floating power supply is used to neutron tube in logging neutron generator, which minimizes the space of high-strength electric field, and reduces the voltage gradient by 1/3 in the high-strength electric field. Under condition of floating power supply pulse width modulation autocontrol is used to stabilize operation of neutron generator in high temperature circumstance

  18. 3D float tracking: in situ floodplain roughness estimation

    NARCIS (Netherlands)

    Straatsma, M.W.

    2009-01-01

    This paper presents a novel technique to quantify in situ hydrodynamic roughness of submerged floodplain vegetation: 3D float tracking. This method uses a custom-built floating tripod that is released on the inundated floodplain and tracked from shore by a robotic total station. Simultaneously, an

  19. Design Optimization and Evaluation of Gastric Floating Matrix Tablet ...

    African Journals Online (AJOL)

    Conclusion: CCD demonstrated the role of the derived equations, contour plots and response surface plots in predicting the values of independent variables for the preparation and optimization of glipizide gastric floating matrix tablet. Keywords: Effervescent, Floating tablet, Design of Experiment, Release kinetics, Central ...

  20. Production of floating pellets using appropriate methods | Suleiman ...

    African Journals Online (AJOL)

    The study investigated into the use of floating materials like candle wax, yeast and baking powder to achieve pellet buoyancy. Ten diets were formulated with incorporation of floating agents; Diet I-YBCT- (yeast-baking powder in cold water -toasted), Diet II-YBCU- (yeast-baking powder in cold water -untoasted) Diet III ...

  1. Design and Evaluation of an Oral Floating Matrix Tablet of ...

    African Journals Online (AJOL)

    Purpose: To develop floating matrix tablets of salbutamol sulphate using ethyl cellulose and acrycoat S-100 as polymers, and sodium bicarbonate, citric acid and tartaric acid as gas generating agents. Methods: Twenty four formulations were prepared and segregated into four major categories, A to D. The floating tablets ...

  2. Design and Evaluation of an Oral Floating Matrix Tablet of ...

    African Journals Online (AJOL)

    Purpose: To develop floating matrix tablets of salbutamol sulphate using ethyl cellulose and acrycoat S-. 100 as polymers, and sodium bicarbonate, citric acid and tartaric acid as gas generating agents. Methods: Twenty four formulations were prepared and segregated into four major categories, A to D. The floating tablets ...

  3. Herbal carrier-based floating microparticles of diltiazem ...

    African Journals Online (AJOL)

    Purpose: To formulate and characterize a gastroretentive floating drug delivery system for diltiazem hydrochloride using psyllium husk and sodium alginate as natural herbal carriers to improve the therapeutic effect of the drug in cardiac patients. Methods: Floating microparticles containing diltiazem hydrochloride were ...

  4. Page | 155 FLOATING CHARGE: A CHILD OF EQUITABLE ...

    African Journals Online (AJOL)

    Fr. Ikenga

    Hence it has been pungently stated that ….. it is evident that crystallization is the transition stage of a floating charge, … which could be quite vulnerable in protecting a creditor's money, to a more reliable security of the fixed charge. However, this is not to say that a floating charge is not desirable in the creation of securities.

  5. A novel grounded to floating admittance converter with electronic control

    Science.gov (United States)

    Prasad, Dinesh; Ahmad, Javed; Srivastava, Mayank

    2018-01-01

    This article suggests a new grounded to floating admittance convertor employing only two voltage differencing transconductance amplifiers (VDTAs). The proposed circuit can convert any arbitrary grounded admittance into floating admittance with electronically controllable scaling factor. The presented converter enjoys the following beneficial: (1) no requirement of any additional passive element (2) scaling factor can be tuned electronically through bias currents of VDTAs (3) no matching constraint required (4) low values of active/passive sensitivity indexes and (5) excellent non ideal behavior that indicates no deviation in circuit behavior even under non ideal environment. Application of the proposed configuration in realization of floating resistor and floating capacitor has been presented and the workability of these floating elements has been confirmed by active filter design examples. SPICE simulations have been performed to demonstrate the performance of the proposed circuits.

  6. Development and evaluation of gastroretentive floating tablets of an antidepressant drug by thermoplastic granulation technique

    Directory of Open Access Journals (Sweden)

    Harshal Ashok Pawar

    2014-06-01

    Full Text Available The present study was undertaken with an aim to formulate, develop and evaluate gastroretentive floating tablets of an antidepressant drug, Venlafaxine HCl (hydrochloride, which release the drug in a sustained manner over a period of 24 h. Three different hydrophobic retardants namely hydrogenated cottonseed oil, carnauba wax, cetyl alcohol and a hydrophilic polymer Methocel® (hydroxy propyl methyl cellulose (HPMC K15M were used in different combinations at different ratios for the preparation of tablets. The tablets were prepared by Hot Melt or Thermoplastic granulation method and evaluated for tablet thickness, hardness, weight variation, friability, floating lag time and in vitro drug release. Formulation F8 with hydrophilic polymer (Methocel® K15M and hydrophobic retardant (carnauba wax in the ratio 1:2.6 (approx. was considered as an optimized formulation. The optimized formulation showed satisfactory sustained drug release and remained buoyant on the surface of the medium for more than 24 h and its release profile was comparable with the marketed formulation (VENTAB-XL 37.5. It can also be concluded that floating drug delivery system of Venlafaxine HCl can be successfully formulated as an approach to increase gastric residence time and thereby improving its bioavailability.

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

    International Nuclear Information System (INIS)

    Sewall, N.R.

    1989-01-01

    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

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

    International Nuclear Information System (INIS)

    Sewall, N.R.; Meassick, S.

    1989-01-01

    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

  9. Effects of pore forming agents on chitosan-graft-poly(N-vinylpyrrolidone) hydrogel properties for use as a matrix for floating drug delivery

    Science.gov (United States)

    Budianto, E.; Al-Shidqi, M. F.; Cahyana, A. H.

    2017-07-01

    Eradicating H. pylori-based infection by using conventional oral dosage form of amoxicillin trihydrate finds difficulties to overcome rapid gastric retention time. Encapsulating amoxicillin trihydrate in floating drug delivery system may solve the problem. In this research, the floating drug delivery system of amoxicillin trihydrate encapsulated in floating chitosan-graft-poly(N-vinyl pyrrolidone) hydrogels containing CaCO3 and NaHCO3 as pore forming agents has been successfully prepared. Pore forming agents used was varied with the ratio of 10 to 25% pore forming agents to total mass of the used materials. The hydrogel were characterizedusing FTIR spectrophotometer and stereo microscope. As pore forming agents compositions increased, the porosity (%) and floating properties increased but followed by decrease in drug entrapment efficiency. Most of the floating hydrogels possessed floating ability longer than 180 min and the highest porosity was found in hydrogel containing 25% NaHCO3. Hydrogel containing CaCO3 showed sustained drug release profile than hydrogel containing NaHCO3. However, the optimum formulation was achieved at composition of 10% NaHCO3 with 57% of drug entrapped within the hydrogel and 43% drug released. The results of these studies show that NaHCO3 is an effective pore forming agents for chitosan-graft-poly(N-vinyl pyrrolidone) hydrogel preparation as compare to CaCO3.

  10. Floating liquid crystalline molecularly imprinted polymer coated carbon nanotubes for levofloxacin delivery.

    Science.gov (United States)

    Zhang, Li-Ping; Tan, Xue-Xia; Huang, Yan-Ping; Liu, Zhao-Sheng

    2018-02-10

    Liquid crystalline molecularly imprinted polymers (LC-MIPs) were low cross-linking MIPs (5-20 mol %) by introducing a LC monomer into the MIP polymerization system to keep the shape of the imprinted cavities due to additional interactions between the mesogenic groups. The multiwalled carbon nanotubes (MWCNTs) coated LC-MIP (MWCNT@LC-MIP) was the first fabricated as a novel floating interaction-controlled DDS. The synthesis was achieved by adding 9-vinylanthracene to obtain the high-density vinyl group functionalized MWCNTs firstly, and then polymerization of LC MIPs was performed on the surface of MWCNTs using a mixture of methacrylic acid, ethylene glycol dimethacrylate, and 4-methyl phenyl dicyclohexyl ethylene (LC monomer) with levofloxacin (LVF) as model template drug. Both template/functional monomer ratio and levels of crosslinker were optimized to obtain the best imprinting factor. Characterizations of polymer were investigated by the transmission electron microscope, nitrogen adsorption, thermogravimetric analysis, Fourier transform infrared spectra and floating behavior studies. The imprinting effect was confirmed by the adsorption isotherms, adsorption kinetics and effect of selectivity. In vitro release studies were examined by the LVF-loaded MWCNT@LC-MIP and the control samples, MWCNT@LC-NIP, MWCNT@MIP, MWCNT@NIP and the bare MWCNT using acetonitrile as the dissolute medium. The release profiles showed an obvious zero-order release of LVF from MWCNT@LC-MIP, which exhibited 3.8 μg/h of the release rate with duration of about 20 h. In vivo pharmacokinetic study displayed the relative bioavailability of the gastro-floating MWCNT@LC-MIP was 578.9%, whereas only 58.0% of MWCNT@MIP and 11.7% of the bared MWCNT. As a conclusion, MWCNT@LC-MIP showed potentials for oral administration by the innovative combination of floating and controlled release properties. Copyright © 2018. Published by Elsevier B.V.

  11. Nuclear Security for Floating Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Skiba, James M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Scherer, Carolynn P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-13

    Recently there has been a lot of interest in small modular reactors. A specific type of these small modular reactors (SMR,) are marine based power plants called floating nuclear power plants (FNPP). These FNPPs are typically built by countries with extensive knowledge of nuclear energy, such as Russia, France, China and the US. These FNPPs are built in one country and then sent to countries in need of power and/or seawater desalination. Fifteen countries have expressed interest in acquiring such power stations. Some designs for such power stations are briefly summarized. Several different avenues for cooperation in FNPP technology are proposed, including IAEA nuclear security (i.e. safeguards), multilateral or bilateral agreements, and working with Russian design that incorporates nuclear safeguards for IAEA inspections in non-nuclear weapons states

  12. Analysis of Switched-Rigid Floating Oscillator

    Directory of Open Access Journals (Sweden)

    Prabhakar R. Marur

    2009-01-01

    Full Text Available In explicit finite element simulations, a technique called deformable-to-rigid (D2R switching is used routinely to reduce the computation time. Using the D2R option, the deformable parts in the model can be switched to rigid and reverted back to deformable when needed during the analysis. The time of activation of D2R however influences the overall dynamics of the system being analyzed. In this paper, a theoretical basis for the selection of time of rigid switching based on system energy is established. A floating oscillator problem is investigated for this purpose and closed-form analytical expressions are derived for different phases in rigid switching. The analytical expressions are validated by comparing the theoretical results with numerical computations.

  13. Preliminary results from NOAMP deep drifting floats

    International Nuclear Information System (INIS)

    Ollitrault, M.

    1989-01-01

    This paper is a very brief and preliminary outline of first results obtained with deep SOFAR floats in the NOAMP area. The work is now going toward more precise statistical estimations of mean and variable currents, together with better tracking to resolve submesoscales and estimate diffusivities due to mesoscale and smaller scale motions. However the preliminary results confirm that the NOAMP region (and surroundings) has a deep mesoscale eddy field that is considerably more energetic that the mean field (r.m.s. velocities are of order 5 cm s -1 ), although both values are diminished compared to the western basin. A data report containing trajectories and statistics is scheduled to be published by IFREMER in the near future. The project main task is to especially study the dispersion of radioactive substances

  14. Sharing risk and reward - floating production contractorship

    International Nuclear Information System (INIS)

    Gisvold, K.M.

    1994-01-01

    The conference paper summarizes the contractual experience so far gained on Petrojarl 1 floating production system and the associated shuttling services on the Norwegian continental shelf. The paper attempts to draw some lines into the future with respect to development of the business format and the evolution of the relationship between the contractor and the various oil companies in question. Turnkey production services as well as transport and project services to the oil industry are provided. The scope of these services ranges from top of the sea bed wellhead to quayside at the refinery, and is based on ownership control of the employed vessels as well as complete manning of all services. 7 figs

  15. Ionizing radiation effects on floating gates

    International Nuclear Information System (INIS)

    Cellere, G.; Paccagnella, A.; Visconti, A.; Bonanomi, M.

    2004-01-01

    Floating gate (FG) memories, and in particular Flash, are the dominant among modern nonvolatile memory technologies. Their performance under ionizing radiation was traditionally studied for the use in space, but has become of general interest in recent years. We are showing results on the charge loss from programmed FG arrays after 10 keV x-rays exposure. Exposure to ionizing radiation results in progressive discharge of the FG. More advanced devices, featuring smaller FG, are less sensitive to ionizing radiation that older ones. The reason is identified in the photoemission of electrons from FG, since at high doses it dominates over charge loss deriving from electron/hole pairs generation in the oxides

  16. First census of floating population in Beijing.

    Science.gov (United States)

    1998-12-01

    This study presents the findings of the first census of the floating population in Beijing, China, in 1997. The census was conducted in 18 urban districts and counties among migrants living or staying in Beijing with household registration elsewhere. In 1997, the floating population amounted to 2.86 million, of whom 2.30 million stayed in Beijing over 1 day. 66.1% were males; 33.9% were females. 1.38 million (59.9%) lived in institutional households. 755,000 (32.9%) formed their own family units; 166,000 (7.2%) lived with resident Beijing families. 12,000 lived in railway stations and 22,000 were homeless. In-migrants numbered 435,000 and out-migrants numbered 42,000 in the preceding 24 hours. 84,000 (a doubling since 1984) were from Hong Kong, Macao, and Taiwan. In-migration was lower by 436,000 persons than in 1994. The decline is attributed to government policy to limit migration and to economic recession. Better communication and transportation facilitate foreign migration. 1.81 million migrants out of 2.30 million lived in 4 urban and 4 suburban districts. The others lived in 10 remote suburban areas. Migrants accounted for 537,000 persons in Chaoyang District (23.3%), 493,000 in Haidan District (21.5%), and 315,000 in Fengtai District (13.7%). The ratio of in-migrants to residents was 1:8 in Beijing urban districts, 1:4 in suburban districts, and 1:10 in remote areas. Stays averaged 19.2 months. 1.81 million had jobs. About 74% came from Hebei, Henan, Zhejiang, Sichuan, Shandong, Jiangsu, and Anhui. Zhejiang migrants stayed the longest (24.9 months), while Jiangsu in-migrants stayed the shortest (16.6 months).

  17. Potential of water surface-floating microalgae for biodiesel production: Floating-biomass and lipid productivities.

    Science.gov (United States)

    Muto, Masaki; Nojima, Daisuke; Yue, Liang; Kanehara, Hideyuki; Naruse, Hideaki; Ujiro, Asuka; Yoshino, Tomoko; Matsunaga, Tadashi; Tanaka, Tsuyoshi

    2017-03-01

    Microalgae have been accepted as a promising feedstock for biodiesel production owing to their capability of converting solar energy into lipids through photosynthesis. However, the high capital and operating costs, and high energy consumption, are hampering commercialization of microalgal biodiesel. In this study, the surface-floating microalga, strain AVFF007 (tentatively identified as Botryosphaerella sudetica), which naturally forms a biofilm on surfaces, was characterized for use in biodiesel production. The biofilm could be conveniently harvested from the surface of the water by adsorbing onto a polyethylene film. The lipid productivity of strain AVFF007 was 46.3 mg/L/day, allowing direct comparison to lipid productivities of other microalgal species. The moisture content of the surface-floating biomass was 86.0 ± 1.2%, which was much lower than that of the biomass harvested using centrifugation. These results reveal the potential of this surface-floating microalgal species as a biodiesel producer, employing a novel biomass harvesting and dewatering strategy. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  18. Floating liquid bridge tensile behavior: Electric-field-induced Young's modulus measurements

    Science.gov (United States)

    Teschke, Omar; Mendez Soares, David; Valente Filho, Juracyr Ferraz

    2013-12-01

    A floating bridge is formed spontaneously when high voltage is applied to polar fluids in two capillary tubes that were in contact and then separated. This bridge bends under its own weight, and its bending profile was used to calculate its Young's modulus. For electric field intensities of ˜106 V/m, water bridges exhibit viscoelastic behavior, with Young's moduli of ˜24 MPa; dimethylsulfoxide (DMSO) bridges exhibited Young's moduli of ˜60 kPa. The scheme devised to measure the voltage drop across the water bridge for high voltages applied between the electrodes shows that the bulk water resistance decreases with increasing voltage.

  19. WindWaveFloat (WWF): Final Scientific Report

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Alla; 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.

  20. Floating Matrix Dosage Form for Propranolol Hydrochloride Based on Gas Formation Technique: Development and In Vitro Evaluation

    OpenAIRE

    CHATURVEDI, Kiran; UMADEVI, S.; VAGHANI, Subhash

    2010-01-01

    Gastroretentive tablets of propranolol hydrochloride were developed by direct compression method using citric acid and sodium bicarbonate as the effervescent base. Hydroxypropyl methylcellulose; HPMC K15M was used to prepare the floating tablets to retard the drug release for 12h in stomach. Na-carboxymethyl cellulose (NaCMC) or carbopol 934P was added to alter the drug release profile or the dimensional stability of the formulation. Dicalcium phosphate (DCP) was used as filler. Formulations ...

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

    Science.gov (United States)

    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.

  2. Floating cultivation of marine cyanobacteria using coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, M.; Yoshida, E.; Takeyama, H.; Matsunaga, T. [Tokyo University of Agriculture and Technology, Tokyo (Japan). Dept. of Biotetechnology

    2000-07-01

    The aim was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. The viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine microalgae was investigated. The marine cyanobacterium Synechococcus sp. NKBC 040607 was found to adhere to floating CFA blocks in liquid culture medium. 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.

  3. A Method for Modeling of Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir

    2013-01-01

    It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine...

  4. Solid dispersions in the development of a nimodipine floating tablet formulation and optimization by artificial neural networks and genetic programming.

    Science.gov (United States)

    Barmpalexis, Panagiotis; Kachrimanis, Kyriakos; Georgarakis, Emanouil

    2011-01-01

    The present study investigates the use of nimodipine-polyethylene glycol solid dispersions for the development of effervescent controlled release floating tablet formulations. The physical state of the dispersed nimodipine in the polymer matrix was characterized by differential scanning calorimetry, powder X-ray diffraction, FT-IR spectroscopy and polarized light microscopy, and the mixture proportions of polyethylene glycol (PEG), polyvinyl-pyrrolidone (PVP), hydroxypropylmethylcellulose (HPMC), effervescent agents (EFF) and nimodipine were optimized in relation to drug release (% release at 60 min, and time at which the 90% of the drug was dissolved) and floating properties (tablet's floating strength and duration), employing a 25-run D-optimal mixture design combined with artificial neural networks (ANNs) and genetic programming (GP). It was found that nimodipine exists as mod I microcrystals in the solid dispersions and is stable for at least a three-month period. The tablets showed good floating properties and controlled release profiles, with drug release proceeding via the concomitant operation of swelling and erosion of the polymer matrix. ANNs and GP both proved to be efficient tools in the optimization of the tablet formulation, and the global optimum formulation suggested by the GP equations consisted of PEG=9%, PVP=30%, HPMC=36%, EFF=11%, nimodipine=14%. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. 33 CFR 149.550 - What are the requirements for lights on a floating hose string?

    Science.gov (United States)

    2010-07-01

    ... lights on a floating hose string? 149.550 Section 149.550 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation Lights on Floating Hose Strings § 149.550 What are the requirements for lights on a floating hose string? Hose strings that are floating or supported on trestles must display the...

  6. Chitosan superporous hydrogel composite-based floating drug delivery system: A newer formulation approach

    Directory of Open Access Journals (Sweden)

    Hitesh Chavda

    2010-01-01

    Full Text Available Objective: In this study efforts have been made to design a drug delivery system based on a superporous hydrogel composite, for floating and sustained delivery of Ranitidine hydrochloride. Materials and Methods: The characterization studies were performed by the measurement of apparent density, porosity, swelling studies, mechanical strength studies, and scanning electron microscopy studies. The prepared formulation was evaluated for buoyant behavior, in vitro drug release, kinetics of drug release, and stability. The release profile of Ranitidine hydrochloride was investigated by changing the release retardant polymer in the formulation. To ascertain the kinetics of drug release, the drug release profiles were fitted to mathematical models that included zero-order, first-order, Higuchi, Hixson-Crowell, Korsmeyer-Peppas, Weibull, and Hopfenberg models. Results: Scanning electron microscopy images clearly indicated the formation of interconnected pores and capillary channels, and cross-linked Chitosan molecules were observed around the peripheries of the pores. The prepared drug delivery system floated and delivered the Ranitidine hydrochloride for about 17 hours. The in vitro drug release from the proposed system was best explained by the Korsmeyer-Peppas model. The values of the diffusion exponent in the Korsmeyer-Peppas model ranged between 0.47 ± 0.02 and 0.66 ± 0.02, which appeared to indicate a coupling of the diffusion and erosion mechanisms, anomalous non-Fickian transport. Conclusion: It was concluded that the proposed floating drug delivery system, based on the superporous hydrogel composite containing Chitosan as a composite material, is promising for stomach-specific delivery of Ranitidine hydrochloride.

  7. RAFOS Float Processing at the Woods Hole Oceanographic Institution

    National Research Council Canada - National Science Library

    Wooding, Christine M; Furey, Heather H; Pachece, Marguerite A

    2005-01-01

    This report and its accompanying web page (http://www.whoi.edu/science/PO/rafos/) describe the processing steps for RAFOS floats, from subscribing to Service Argos to plotting the final data for a data report...

  8. WindFloat Pacific Project, Final Scientific and Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Banister, Kevin [Principle Power, Inc., Emeryville, CA (United States)

    2017-01-17

    PPI’s WindFloat Pacific project (WFP) was an up to 30 MW floating offshore wind demonstration project proposed off the Coast of Oregon. The project was to be sited approximately 18 miles due west of Coos Bay, in over 1000 ft. of water, and is the first floating offshore wind array proposed in the United States, and the first offshore wind project of any kind proposed off the West Coast. PPI’s WindFloat, a semi-submersible foundation designed for high-capacity (6MW+) offshore wind turbines, is at the heart of the proposed project, and enables access to the world class wind resource at the project site and, equally, to other deep water, high wind resource areas around the country.

  9. Herbal carrier-based floating microparticles of diltiazem ...

    African Journals Online (AJOL)

    Various physicochemical properties of the floating microspheres were characterized, including drug content, particle ... develop the delivery system. Keywords: Diltiazem, Cardiac disease, Psyllium husk, Sodium alginate, Microsphere, Microparticle, ... mechanical strength of the microparticles was improved by gentle stirring ...

  10. Floating Cities: ‘we have a dream to realize’

    NARCIS (Netherlands)

    R.E. de Graaf; ir. Floris Boogaard

    2013-01-01

    A fundamental new approach to urban development is needed for the challenges of the 21st century. Floating houses and cities can accommodate future urbanization without sacrificing land and provide a sustainable living.

  11. Multifractal analysis of managed and independent float exchange rates

    Science.gov (United States)

    Stošić, Darko; Stošić, Dusan; Stošić, Tatijana; Stanley, H. Eugene

    2015-06-01

    We investigate multifractal properties of daily price changes in currency rates using the multifractal detrended fluctuation analysis (MF-DFA). We analyze managed and independent floating currency rates in eight countries, and determine the changes in multifractal spectrum when transitioning between the two regimes. We find that after the transition from managed to independent float regime the changes in multifractal spectrum (position of maximum and width) indicate an increase in market efficiency. The observed changes are more pronounced for developed countries that have a well established trading market. After shuffling the series, we find that the multifractality is due to both probability density function and long term correlations for managed float regime, while for independent float regime multifractality is in most cases caused by broad probability density function.

  12. Review of radiological problems of floating nuclear power plants

    International Nuclear Information System (INIS)

    Rodd, T.

    1982-01-01

    Radiological problems associated with floating nuclear power plants under both normal operation and accident conditions are discussed. In the latter case, aspects of both the airborne and liquid pathways are reviewed

  13. Can Heavier Liquid Float on Top of a Lighter One?

    International Nuclear Information System (INIS)

    Ayyad, A. H.; Takrori, F.

    2011-01-01

    We report on a first observation of a floating spherical Hg (density 13 g/cm 3 ) drop on top of a glycerin (density 1.26 g/cm 3 ) drop, the latter is hemispherical and about four times larger in volume. This observation is clearly against nature's gravity law and has never been reported before. Here we present spectacular high resolution photos that clearly demonstrate this remarkable floating phenomenon. Using milli-Q water, the Hg drop would stay down adhered at the triple line. Instead, the coincidental use of tap water displays the same phenomenon. Increasing the volume of the supporting liquid to a certain value causes the Hg drop to sink. A 5-M NaCl aqueous solution is found enough to show the same floating phenomenon. This floating mercury as a phenomenon is puzzling. On this length scale it seems that surface tension and curvature dominate over gravity. (fundamental areas of phenomenology (including applications))

  14. Determination of bacterial and fungal numbers in floats of pre ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-20

    Apr 20, 2009 ... skim milk or 2% Tween 80 were used to detect proteolytic and lipolytic activity, respectively. While the media containing 0, 10, 15 and 25% NaCl were used to count micro-organisms in the main soaking float and the media containing 0, 5 and 10% NaCl for all other pre-tanning processes floats. pH values of ...

  15. Enhancing Water Evaporation with Floating Synthetic Leaves

    Science.gov (United States)

    Boreyko, Jonathan; Vieitez, Joshua; Berrier, Austin; Roseveare, Matthew; Shi, Weiwei

    2017-11-01

    When a wetted nanoporous medium is exposed to a subsaturated ambient environment, the water menisci assume a concave curvature to achieve a negative pressure. This negative water pressure is required to balance the mismatch in water activity across the water-air interface to achieve local equilibrium. Here, we show that the diffusive evaporation rate of water can be greatly modulated by floating a nanoporous synthetic leaf at the water's free interface. For high ambient humidities, adding the leaf serves to enhance the evaporation rate, presumably by virtue of the menisci enhancing the effective liquid-vapor surface area. For low humidities, the menisci cannot achieve a local equilibrium and retreat partway into the leaf, which increases the local humidity directly above the menisci. In light of these two effects, we find the surprising result that leaves exposed to an ambient humidity of 90 percent can evaporate water at the same rate as leaves exposed to only 50 percent humidity. These findings have implications for using synthetic trees to enhance steam generation or water harvesting. This work was supported by the National Science Foundation (CBET-1653631).

  16. Evaluation of floating impeller phenomena in a Gyro centrifugal pump.

    Science.gov (United States)

    Nishimura, Ikuya; Ichikawa, S; Mikami, M; Ishitoya, H; Motomura, T; Kawamura, M; Linneweber, J; Glueck, J; Shinohara, T; Nosé, Y

    2013-01-01

    The Gyro centrifugal pump developed as a totally implantable artificial heart was designed with a free impeller, in which the rotational shaft (male bearing) of the impeller was completely separated from the female bearing. For this type of pump, it is very important to keep the proper magnet balance (impeller-magnet and actuator-magnet) in order to prevent thrombus formation and/or bearing wear. When the magnet balance is not proper, the impeller is jerked down into the bottom bearing. On the other hand, if magnet balance is proper, the impeller lifted off the bottom of the pump housing within a certain range of pumping conditions. In this study, this floating phenomenon was investigated in detail. The floating phenomenon was proved by observation of the impeller behavior using a transparent acrylic pump. The impeller floating phenomenon was mapped on a pump performance curve. The impeller floating phenomenon is affected by the magnet-magnet coupling distance and rotational speed of the impeller. In order to keep the proper magnet balance and to maintain the impeller floating phenomenon at the driving condition of right and left pump, the magnet-magnet coupling distance was altered by a spacer which was installed between the pump and actuator. It became clear that the same pump could handle different conditions (right and left ventricular assist), by just changing the thickness of the spacer. When magnet balance is proper, the floating impeller phenomenon occurs automatically in response to the impeller rev. It is called "the dynamic RPM suspension".

  17. Position control of a floating nuclear power plant

    International Nuclear Information System (INIS)

    Motohashi, K.; Hamamoto, T.; Sasaki, R.; Kojima, M.

    1993-01-01

    In spite of the increasing demand of electricity in Japan, the sites of nuclear power plants suitable for conventional seismic regulations become severely limited. Under these circumstances, several types of advanced siting technology have been developed. Among them, floating power plants have a great advantage of seismic isolation that leads to the seismic design standardization and factory fabrication. The feasibility studies or preliminary designs of floating power plants enclosed by breakwaters in the shallow sea have been carried out last two decades in U.S. and Japan. On the other hand, there are few investigations on the dynamic behavior of floating power plants in the deep sea. The offshore floating nuclear power plants have an additional advantage in that large breakwaters are not required, although the safety checking is inevitable against wind-induced waves. The tension-leg platforms which have been constructed for oil drilling in the deep sea seem to be a promising offshore siting technology of nuclear power plants. The tension-leg mooring system can considerably restrain the heave and pitch of a floating power plant because of significant stiffness in the vertical direction. Different from seismic effects, wind-induced waves may be predicted in advance by making use of ocean weather forecasts using artificial satellites. According to the wave prediction, the position of the floating plant may be controlled by adjusting the water content in ballast tanks and the length of tension-legs before the expected load arrives. The position control system can reduce the wave force acting on the plant and to avoid the unfavorable response behavior of the plant. In this study a semi-submerged circular cylinder with tension-legs is considered as a mathematical model. The configuration of circular cylinder is effective because the dynamic behavior does not depend on incident wave directions. It is also unique in that it can obtain the closed-form solution of

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

    Science.gov (United States)

    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 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).

  19. Integrated dual-tomography for refractive index analysis of free-floating single living cell with isotropic superresolution.

    Science.gov (United States)

    B, Vinoth; Lai, Xin-Ji; Lin, Yu-Chih; Tu, Han-Yen; Cheng, Chau-Jern

    2018-04-13

    Digital holographic microtomography is a promising technique for three-dimensional (3D) measurement of the refractive index (RI) profiles of biological specimens. Measurement of the RI distribution of a free-floating single living cell with an isotropic superresolution had not previously been accomplished. To the best of our knowledge, this is the first study focusing on the development of an integrated dual-tomographic (IDT) imaging system for RI measurement of an unlabelled free-floating single living cell with an isotropic superresolution by combining the spatial frequencies of full-angle specimen rotation with those of beam rotation. A novel 'UFO' (unidentified flying object) like shaped coherent transfer function is obtained. The IDT imaging system does not require any complex image-processing algorithm for 3D reconstruction. The working principle was successfully demonstrated and a 3D RI profile of a single living cell, Candida rugosa, was obtained with an isotropic superresolution. This technology is expected to set a benchmark for free-floating single live sample measurements without labeling or any special sample preparations for the experiments.

  20. Free-floating atmospheric pressure ball plasmas

    Science.gov (United States)

    Wurden, G. A.; Ticos, C.; Wang, Z.; Wurden, C. J. V.

    2007-11-01

    A long-lived (0.3 second, 10-20 cm diameter) ball plasma floating in the air above a water surface has been formed and studied in the laboratory. A 0.4 - 1 mF capacitor is charged to 4-5 kV, and subsequently discharged (30-60 Amps, 20-50 msec duration) into central copper cathode held fixed just below the surface of a bucket of water (with a weak solution of various salts in distilled water, such as CuSO4 or CuCl2, LiCl or NaCl). An underwater ring anode completes the circuit. A bubble of hot vapor from the water surface rises up in the first few milliseconds, and changes from a mushroom cloud with stalk, to a detached quasi-spherical object, finally evolving into a vortex ring. The plasma consists of ionized water vapor, with positive salts and OH- radicals, as well as molecular species, and it completely excludes nitrogen or oxygen from the rising plasma structure. A fine boundary layer is visible in orange, in contrast to a green ball interior when using Cu/CuSO4, and filamentary structures are visible at late times. Finally, a whisp of smoke ring is observed as a residue. A variety of visible and infrared imaging (both video and still cameras) are used, along with 200-800 nm time & space resolved spectroscopy, to identify features of this laboratory analog to ball lightning. Possible applications include a windowless ball- plasma powered pulsed copper vapor laser operating at 510 nm.

  1. The study to estimate the floating population in Seoul, Korea.

    Science.gov (United States)

    Lee, Geon Woo; Lee, Yong Jin; Kim, Youngeun; Hong, Seung-Han; Kim, Soohwaun; Kim, Jeong Soo; Lee, Jong Tae; Shin, Dong Chun; Lim, Youngwook

    2017-01-01

    Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the official census count, the floating population in 25 regions was calculated. The reduced level of deaths among the floating population in 14 regions having the roadside monitoring station was calculated as assuming a 20% reduction of mobile emission based on the policy. The hourly floating population size was calculated by applying the hourly population ratio to the regional population size as specified in the official census count. The number of people moving from 5 a.m. to next day 1 a.m. could not be precisely calculated when the population size was applied, but no issue was observed that would trigger a sizable shift in the rate of population change. The three patterns of increase, decrease, and no change of population in work hours were analyzed. When the concentration of particulate matter less than 10 μm in aerodynamic diameter was reduced by 20%, the number of excess deaths varied according to the difference of the floating population. The effective establishment of directions to manage the pollutants in cities should be carried out by considering the floating population. Although the number of people using the metro system is only an estimate, this disadvantage was supplemented by calculating inflow and outflow ratio of metro users per time in the total floating population in each region. Especially, 54% of metro usage in public transport causes high reliability in application.

  2. The study to estimate the floating population in Seoul, Korea

    Directory of Open Access Journals (Sweden)

    Geon Woo Lee

    2017-05-01

    Full Text Available Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the official census count, the floating population in 25 regions was calculated. The reduced level of deaths among the floating population in 14 regions having the roadside monitoring station was calculated as assuming a 20% reduction of mobile emission based on the policy. The hourly floating population size was calculated by applying the hourly population ratio to the regional population size as specified in the official census count. The number of people moving from 5 a.m. to next day 1 a.m. could not be precisely calculated when the population size was applied, but no issue was observed that would trigger a sizable shift in the rate of population change. The three patterns of increase, decrease, and no change of population in work hours were analyzed. When the concentration of particulate matter less than 10 μm in aerodynamic diameter was reduced by 20%, the number of excess deaths varied according to the difference of the floating population. The effective establishment of directions to manage the pollutants in cities should be carried out by considering the floating population. Although the number of people using the metro system is only an estimate, this disadvantage was supplemented by calculating inflow and outflow ratio of metro users per time in the total floating population in each region. Especially, 54% of metro usage in public transport causes high reliability in application.

  3. Pengaruh Frekuensi Melihat Iklan Floating terhadap Tingkat Kesadaran Merek

    Directory of Open Access Journals (Sweden)

    Forddhanto Bimantoro

    2013-11-01

    Full Text Available Abstract: Floating ad  is online advertisement aiming to stimulate brand awareness by increasing familiarity through reexposing advertisement. This research examines the influence of ARCO Depok members’ exposure of floating ad at www.detik.com to their brand awareness about Samsung LED TV. The frequency of consuming the advertisement is differentiated into three categories, namely three times, five times and never. The result shows that the respondents’ exposure of floating ad could influence the level of brand awareness as much as 40.7%. However, this tendency was not represented in the category of five times. The result also shows that the only control variable which was able to significantly influence the level of brand awareness was the variable of respondents’ visitation to the site of detik.com. Abstrak: Iklan floating merupakan iklan di media internet yang bertujuan mencapai kesadaran merek dengan cara meningkatkan familiarity melalui frekuensi pengulangan iklan. Frekuensi melihat iklan floating dibedakan  dengan memilah kelompok responden yang dikenai frekuensi melihat iklan 3 kali, 5 kali dan tidak melihat iklan. Penelitian ini menguji pengaruh frekuensi melihat iklan floating di www.detik.com terhadap tingkat kesadaran merek Samsung LED TV pada warga ARCO Depok, Jawa Barat. Hasil penelitian menunjukkan bahwa frekuensi melihat iklan floating dapat mempengaruhi tingkat kesadaran merek sebesar 40,7%; namun tidak terbukti pada kelompok yang melihat iklan sebanyak lima kali. Variabel kontrol yang mampu mempengaruhi tingkat kesadaran merek secara signifikan hanya variabel kunjungan responden ke detik.com.Â

  4. Direct probing of electron and hole trapping into nano-floating-gate in organic field-effect transistor nonvolatile memories

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Ze-Qun; Wang, Shun; Chen, Jian-Mei; Gao, Xu; Dong, Bin, E-mail: wangsd@suda.edu.cn, E-mail: chilf@suda.edu.cn, E-mail: bdong@suda.edu.cn; Chi, Li-Feng, E-mail: wangsd@suda.edu.cn, E-mail: chilf@suda.edu.cn, E-mail: bdong@suda.edu.cn; Wang, Sui-Dong, E-mail: wangsd@suda.edu.cn, E-mail: chilf@suda.edu.cn, E-mail: bdong@suda.edu.cn [Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123 (China)

    2015-03-23

    Electron and hole trapping into the nano-floating-gate of a pentacene-based organic field-effect transistor nonvolatile memory is directly probed by Kelvin probe force microscopy. The probing is straightforward and non-destructive. The measured surface potential change can quantitatively profile the charge trapping, and the surface characterization results are in good accord with the corresponding device behavior. Both electrons and holes can be trapped into the nano-floating-gate, with a preference of electron trapping than hole trapping. The trapped charge quantity has an approximately linear relation with the programming/erasing gate bias, indicating that the charge trapping in the device is a field-controlled process.

  5. Direct probing of electron and hole trapping into nano-floating-gate in organic field-effect transistor nonvolatile memories

    International Nuclear Information System (INIS)

    Cui, Ze-Qun; Wang, Shun; Chen, Jian-Mei; Gao, Xu; Dong, Bin; Chi, Li-Feng; Wang, Sui-Dong

    2015-01-01

    Electron and hole trapping into the nano-floating-gate of a pentacene-based organic field-effect transistor nonvolatile memory is directly probed by Kelvin probe force microscopy. The probing is straightforward and non-destructive. The measured surface potential change can quantitatively profile the charge trapping, and the surface characterization results are in good accord with the corresponding device behavior. Both electrons and holes can be trapped into the nano-floating-gate, with a preference of electron trapping than hole trapping. The trapped charge quantity has an approximately linear relation with the programming/erasing gate bias, indicating that the charge trapping in the device is a field-controlled process

  6. Bio-Argo Floats Reveal Subsurface Structure of Indian Ocean Eddies

    Science.gov (United States)

    Strutton, P. G.; Phillips, H. E.; Trull, T. W.; Duran, E.; Pump, S.

    2015-12-01

    There is increasing recognition that eddies modulate open ocean productivity, and that this influence depends on both eddy source and their evolution. Eddies in the southeast Indian Ocean have been recognised, from satellite remote sensing of sea surface height and ocean colour, as important pathways for the westward transport of elevated biomass from the eastern boundary Leeuwin Current into the oligotrophic South Indian Ocean. Further it has been hypothesized that, in some eddies, processes at the base of the mixed layer stimulate productivity and sustain phytoplankton biomass for much longer than would be expected from westward advection alone. Here we present high-frequency profiles of temperature, salinity, chlorophyll, backscatter and oxygen from autonomous floats in anti-cyclonic and cyclonic eddies in the South Indian Ocean. Satellite sea surface height data confirmed that the floats remained trapped in their respective eddies from winter to early summer, sampling the upper 300 m of the water column 6-8 times per day. The eddies were larger than average for this region, with mean amplitude and radius of 18.1 (19.3) cm and 143 (97) km for the anticyclonic (cyclonic) eddies. The total concentration of chlorophyll in the mixed layer remained relatively constant, although its vertical distribution changed over time. From September to October, it was evenly distributed throughout the mixed layer of both eddies. With the onset of spring warming, the chlorophyll became concentrated at greater depth with less chlorophyll at the surface. Satellite measurements of surface chlorophyll were 3-5 times lower than the float surface measurement throughout the record, partly because of the vertical structure in chlorophyll. There was no significant change in oxygen saturation state coincident with high phytoplankton concentrations at depth, indicating no net community production. The eddies appear to self-sustain their biomass.

  7. Application of Floating Photovoltaic Energy Generation Systems in South Korea

    Directory of Open Access Journals (Sweden)

    Sun-Hee Kim

    2016-12-01

    Full Text Available In order to mitigate air pollution problems caused mainly by the excessive emission of carbon dioxide, in 2012, the South Korean government decided to introduce a renewable portfolio standards (RPS program that requires electricity providers to gradually increase their production of renewable energy. In order to meet the government’s target through this RPS program, electricity providers in Korea have looked to various types of new and renewable energy resources, such as biomass, wind, and solar. Recently, floating photovoltaic (PV systems have attracted increased interest in Korea as a desirable renewable energy alternative. This paper provides a discussion of recent research into floating PV systems and the installation of floating PV power plants in Korea from 2009 to 2014. To date, thirteen floating PV power plants have been installed in Korea, and several plans are underway by many different organizations, including government-funded companies, to install more floating PV power plants with various generation capacities. These building trends are expected to continue due to the Korean government’s RPS program.

  8. Free-floating planets from microlensing

    Science.gov (United States)

    Sumi, Takahiro

    2014-06-01

    Gravitational microlensing has an unique sensitivity to exoplanets at outside of the snow-line and even exoplanets unbound to any host stars because the technique does not rely on any light from the host but the gravity of the lens. MOA and OGLE collaborations reported the discovery of a population of unbound or distant Jupiter-mass objects, which are almost twice (1.8_{-0.8}^{+1.7}) as common as main-sequence stars, based on two years of gravitational microlensing survey observations toward the Galactic Bulge. These planetary-mass objects have no host stars that can be detected within about ten astronomical units by gravitational microlensing. However a comparison with constraints from direct imaging suggests that most of these planetary-mass objects are not bound to any host star. The such short-timescale unbound planetary candidates have been detected with the similar rate in on-going observations and these groups are working to update the analysis with larger statistics. Recently, there are also discoveries of free-floating planetary mass objects by the direct imaging in young star-forming regions and in the moving groups, but these objects are limited to massive objects of 3 to 15 Jupiter masses.They are more massive than the population found by microlensing. So they may be a different population with the different formation process, either similar with that of stars and brown dwarfs, or formed in proto-planetary disks and subsequently scattered into unbound or very distant orbits. It is important to fill the gap of these mass ranges to fully understand these populations. The Wide Field Infrared Survey Telescope (WFIRST) is the highest ranked recommendation for a large space mission in the recent New Worlds, New Horizons (NWNH) in Astronomy and Astrophysics 2010 Decadal Survey. Exoplanet microlensing program is one of the primary science of WFIRST. WFIRST will find about 3000 bound planets and 2000 unbound planets by the high precision continuous survey 15 min

  9. Develop of a generator of current impulses with floating electrodes

    International Nuclear Information System (INIS)

    Munoz, Diana; Velasquez, Augusto; Roman Francisco

    1999-01-01

    Under very defined conditions, the floating electrodes have the property of generating repetitive current impulses and of constant energy, which can have diverse electric applications. One of these applications is described in this paper: The construction of a prototype generates of repetitive impulses of current, of constant energy, with floating electrodes. In the design it was defined the available energy for the discharge starting from the capacity of the floating electrode. The distances inter-electrodes they were obtained starting from the field's electric disruptive. Once it determines two the electric parameters; the generator were modeled with the program A TP/EMTP. In this article the results of the modeling and the obtained mensurations of the currents are presented and the generator prototype

  10. Expanded polystyrene (EPS) floats for surveillance of Ochlerotatus japonicus.

    Science.gov (United States)

    Scott, Jamesina J; Crans, Wayne J

    2003-12-01

    Blocks of expanded polystyrene (EPS) were placed in a variety of habitats to investigate their potential as an egg-collection device for container-dwelling Aedes and Ochlerotatus species. Eggs from Ochlerotatus japonicus, Oc. triseriatus, Oc. hendersoni, and Aedes albopictus were collected with EPS floats. The float provides an inexpensive, low-maintenance alternative to the Centers for Disease Control ovitrap for sampling container-dwelling mosquito species that are important vectors of disease. Eggs collected on the floats have many potential applications, including use in routine population surveillance; detection of Oc. japonicus, Ae. albopictus, and other container-dwelling species in new areas; species distribution studies; natural transovarial transmission studies; ovipositional studies; collection of local field populations for insecticide resistance assays; assessment of adulticiding efficacy; and establishment of new laboratory colonies.

  11. Numerical modelling of floating debris in the world's oceans.

    Science.gov (United States)

    Lebreton, L C-M; Greer, S D; Borrero, J C

    2012-03-01

    A global ocean circulation model is coupled to a Lagrangian particle tracking model to simulate 30 years of input, transport and accumulation of floating debris in the world ocean. Using both terrestrial and maritime inputs, the modelling results clearly show the formation of five accumulation zones in the subtropical latitudes of the major ocean basins. The relative size and concentration of each clearly illustrate the dominance of the accumulation zones in the northern hemisphere, while smaller seas surrounded by densely populated areas are also shown to have a high concentration of floating debris. We also determine the relative contribution of different source regions to the total amount of material in a particular accumulation zone. This study provides a framework for describing the transport, distribution and accumulation of floating marine debris and can be continuously updated and adapted to assess scenarios reflecting changes in the production and disposal of plastic worldwide. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Numerical investigation of floating breakwater movement using SPH method

    Directory of Open Access Journals (Sweden)

    A. Najafi-Jilani

    2011-06-01

    Full Text Available In this work, the movement pattern of a floating breakwater is numerically analyzed using Smoothed Particle Hydrodynamic (SPH method as a Lagrangian scheme. At the seaside, the regular incident waves with varying height and period were considered as the dynamic free surface boundary conditions. The smooth and impermeable beach slope was defined as the bottom boundary condition. The effects of various boundary conditions such as incident wave characteristics, beach slope, and water depth on the movement of the floating body were studied. The numerical results are in good agreement with the available experimental data in the literature The results of the movement of the floating body were used to determine the transmitted wave height at the corresponding boundary conditions

  13. Investigation of Tank 241-AN-101 Floating Solids

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, Douglas P. [Washington River Protection Solutions, LLC, Richland, VA (United States); Meznarich, H. K. [Washington River Protection Solutions, LLC, Richland, VA (United States)

    2017-10-30

    Tank 241-AN-101 is the receiver tank for retrieval of several C-Farms waste tanks, including Tanks 241-C-102 and 241-C-111. Tank 241 C 111 received first-cycle decontamination waste from the bismuth phosphate process and Plutonium and Uranium Extraction cladding waste, as well as hydraulic fluid. Three grab samples, 1AN-16-01, 1AN-16-01A, and 1AN-16-01B, were collected at the surface of Tank 241-AN-101 on April 25, 2016, after Tank 241-C-111 retrieval was completed. Floating solids were observed in the three grab samples in the 11A hot cell after the samples were received at the 222-S Laboratory. Routine chemical analyses, solid phase characterization on the floating and settled solids, semivolatile organic analysis mainly on the aqueous phase for identification of degradation products of hydraulic fluids were performed. Investigation of the floating solids is reported.

  14. Optimal Control of a Ballast-Stabilized Floating Wind Turbine

    DEFF Research Database (Denmark)

    Christiansen, Søren; Knudsen, Torben; Bak, Thomas

    2011-01-01

    Offshore wind energy capitalizes on the higher and less turbulent wind speeds at sea. The use of floating structures for deeper waters is being explored. The control objective is a tradeoff between power capture and fatigue, especially that produced by the oscillations caused by the reduced...... structural stiffness of a floating installation in combination with a coupling between the fore–aft motion of the tower and the blade pitch. To address this problem, the present paper models a ballast-stabilized floating wind turbine, and suggests a linear quadratic regulator (LQR) in combination with a wind...... estimator and a state observer. The results are simulated using aero elastic code and analysed in terms of damage equivalent loads. When compared to a baseline controller, this controller clearly demonstrates better generator speed and power tracking while reducing fatigue loads....

  15. Capture of free-floating planets by planetary systems

    Science.gov (United States)

    Goulinski, Nadav; Ribak, Erez N.

    2018-01-01

    Evidence of exoplanets with orbits that are misaligned with the spin of the host star may suggest that not all bound planets were born in the protoplanetary disc of their current planetary system. Observations have shown that free-floating Jupiter-mass objects can exceed the number of stars in our Galaxy, implying that capture scenarios may not be so rare. To address this issue, we construct a three-dimensional simulation of a three-body scattering between a free-floating planet and a star accompanied by a Jupiter-mass bound planet. We distinguish between three different possible scattering outcomes, where the free-floating planet may get weakly captured after the brief interaction with the binary, remain unbound or 'kick out' the bound planet and replace it. The simulation was performed for different masses of the free-floating planets and stars, as well as different impact parameters, inclination angles and approach velocities. The outcome statistics are used to construct an analytical approximation of the cross-section for capturing a free-floating planet by fitting their dependence on the tested variables. The analytically approximated cross-section is used to predict the capture rate for these kinds of objects, and to estimate that about 1 per cent of all stars are expected to experience a temporary capture of a free-floating planet during their lifetime. Finally, we propose additional physical processes that may increase the capture statistics and whose contribution should be considered in future simulations in order to determine the fate of the temporarily captured planets.

  16. Modulating Drug Release from Gastric-Floating Microcapsules through Spray-Coating Layers

    Science.gov (United States)

    Tan, Chaoyang Nicholas; Loo, Say Chye Joachim

    2014-01-01

    Floating dosage forms with prolonged gastric residence time have garnered much interest in the field of oral delivery. However, studies had shown that slow and incomplete release of hydrophobic drugs during gastric residence period would reduce drug absorption and cause drug wastage. Herein, a spray-coated floating microcapsule system was developed to encapsulate fenofibrate and piroxicam, as model hydrophobic drugs, into the coating layers with the aim of enhancing and tuning drug release rates. Incorporating fenofibrate into rubbery poly(caprolactone) (PCL) coating layer resulted in a complete and sustained release for up to 8 h, with outermost non-drug-holding PCL coating layer serving as a rate-controlling membrane. To realize a multidrug-loaded system, both hydrophilic metformin HCl and hydrophobic fenofibrate were simultaneously incorporated into these spray-coated microcapsules, with metformin HCl and fenofibrate localized within the hollow cavity of the capsule and coating layer, respectively. Both drugs were observed to be completely released from these coated microcapsules in a sustained manner. Through specific tailoring of coating polymers and their configurations, piroxicam loaded in both the outer polyethylene glycol and inner PCL coating layers was released in a double-profile manner (i.e. an immediate burst release as the loading dose, followed by a sustained release as the maintenance dose). The fabricated microcapsules exhibited excellent buoyancy in simulated gastric fluid, and provided controlled and sustained release, thus revealing its potential as a rate-controlled oral drug delivery system. PMID:25470374

  17. Flexible-hybrid sequential floating search in statistical feature selection

    Czech Academy of Sciences Publication Activity Database

    Somol, Petr; Novovičová, Jana; Pudil, Pavel

    2006-01-01

    Roč. 44, č. 4109 (2006), s. 623-639 ISSN 0302-9743. [Joint IAPR International Workshops SSPR 2006 and SPR 2006. Hong Kong , 17.08.2006-19.08.2006] R&D Projects: GA AV ČR IAA2075302; GA MŠk 1M0572 Grant - others:Commision EU(XE) FP6507752 Institutional research plan: CEZ:AV0Z10750506 Keywords : feature selection * flexible-hybrid * sequential floating search Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.402, year: 2005 http://library.utia.cas.cz/separaty/historie/somol-flexible-hybrid sequential floating search in statistical feature selection.pdf

  18. Floating electrode microelectromechanical system capacitive switches: A different actuation mechanism

    Science.gov (United States)

    Papaioannou, G.; Giacomozzi, F.; Papandreou, E.; Margesin, B.

    2011-08-01

    The paper investigates the actuation mechanism in floating electrode microelectromechanical system capacitive switches. It is demonstrated that in the pull-in state, the device operation turns from voltage to current controlled actuation. The current arises from Poole-Frenkel mechanism in the dielectric film and Fowler-Nordheim in the bridge-floating electrode air gap. The pull-out voltage seems to arise from the abrupt decrease of Fowler-Nordheim electric field intensity. This mechanism seems to be responsible for the very small difference with respect to the pull-in voltage.

  19. Development of floating production systems for the new era

    International Nuclear Information System (INIS)

    Wennesland, J.M.

    1995-01-01

    Maritime Group will give a presentation of present and future trends within the floating production area. Based on the successful operation of Petrojarl 1 (Tentech 885) and now lately the Gryphon A (Tentech 850 C) operated by Kerr McGee a number of floating production systems are now under construction/design for North Sea applications. A status of three developments will be given with emphasize on field development scenarios and market opportunities for the vessels. Based on these on-going projects a discussion of future development trends and possibilities will be presented with special attention to making smaller North-Sea oil fields economically profitable

  20. MULTIMERMAID for Mariscope. A dedicated Accoustic Float for Monitoring of the Oceans

    Science.gov (United States)

    Hello, Y.; Bonnieux, S.; Argentino, J. F.; Yegikyan, M.; Nolet, G.

    2014-12-01

    Delays of seismic P waves are used to make scans or 3D images of the variations in seismic wave speed in the Earth's interior using the techniques of seismic tomography. Observations of such delays are ubiquitous on the continents but rare in oceanic regions, mostly because of the large cost associated with deploying ocean-bottom seismometers. At the same time, several thousand free-drifting profiling floats measure the temperature, salinity and current of the upper 2000 m of the ocean in the Argo program, but are incapable to record and transmit seismic signals. Simons et al. (JGR, 2009) developed the idea to use such floats in order to compensate for the lack of seismic delay observations, especially in the southern hemisphere. We built and tested a prototype of such a seismological sensor using an Apex float from Teledyne Webb Research, a Rafos hydrophone, and electronics developed in collaboration with Osean. Since 2012, these floats have been deployed in the Mediterranean, in the South Indian Ocean, and more recently near the Galapagos islands in the Pacific (see abstract by Nolet et al.). A new prototype " MultiMermaid " spherical is at present in final phase of validation. Using a 37" glass sphere, the lithium battery capacity is greatly superior to that of the Mermaid. It has an instrument compartment that allows for multidisciplinary observations (seismic and kHz acoustics, magnetic field, temperature, bathymetry) and will be programmable. The maximum depth will be 3-4 km. Battery consumption by the pump has been reduced, and the durability depends mostly on CPU usage while drifting, amount of data transmitted but should be five years or more. The Multimermaid can serve biologists by providing a global monitoring of whale and dolphin sounds, seismic tomography by providing worldwide coverage of P wave arrival times, and oceanographers by providing ocean temperature, bathymetry and information on deep currents. Based on an ARM-Cortex M4 microprocessor

  1. The response of pile-guided floats subjected to dynamic loading : volume I final report.

    Science.gov (United States)

    2014-08-01

    Pile : - : Guided floats can be a desirable alternative to stationary berthing structures. Both floats and guide piles are subjected to dynamic : forces such as wind generated waves and impacts from vessels. This project developed a rational basis fo...

  2. Comparative clinical study in plaque removal efficacy of a new sonic toothbrush (Float-Brush) with floating bristle action.

    Science.gov (United States)

    Ojima, Miki; Shizukuishi, Satoshi; Matsuo, Tadayuki; Kanesaki, Nobuo; Hanioka, Takashi

    2003-01-01

    Floating action toothbrush bristles have been incorporated into a V-shaped sonic toothbrush. The base of the bristles moves down or up according to the pressure of the toothbrush being applied to a tooth surface. It was thought that this floating action with sonic vibration may generate new motion for increased plaque removal efficacy through increased contact between bristles and tooth surfaces. The objective of this investigation was to compare the plaque removal efficacy of a sonic toothbrush with floating bristle action (Float-Brush) to either a conventional V-shaped sonic toothbrush (Techno-Brush) or a manual toothbrush. A single-blind, three-treatment cross-over study was performed on 42 subjects. Each subject refrained from brushing for 24 hours, followed by assessment for dental plaque on the Ramfjord teeth employing the Rustogi Modified Navy Plaque Index. Plaque removal efficacy was determined by the percentage of plaque score reduction in a single-use toothbrushing under supervision for two minutes. Forty participants completed this study. No significant difference in pre-brushing plaque scores was detected among the three toothbrushes. In the comparison of whole mouth mean scores, plaque removal efficacy of the Float-Brush (65.0%) was significantly higher than that of the Techno-Brush (59.1%, p = 0.0487) and the manual toothbrush (50.9%, p Brush was similar to whole mouth scores, when comparing the gumline and interproximal tooth area scores. These findings indicate the superiority of the Float-Brush for plaque removal compared to the Techno-Brush and the manual toothbrush.

  3. Empirical Algorithms to Predict pH and Aragonite Saturation State on SOCCOM Biogeochemical Argo Floats in the Pacific Sector of the Southern Ocean

    Science.gov (United States)

    Williams, N. L.; Juranek, L. W.; Feely, R. A.; Johnson, K. S.; Russell, J. L.

    2016-02-01

    The Southern Ocean plays a major role in the global uptake, transport, and storage of both heat and carbon, yet it remains one of the least-sampled regions of the ocean. The Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) project aims to fill the observational gaps by deploying over 200 autonomous profiling floats in the Southern Ocean over the next several years. Initial float deployments have greatly expanded our observational capability to include wintertime measurements as well as under-ice measurements, and many of these floats include novel biogeochemical sensors (pH, nitrate, oxygen). Here we present empirical algorithms that can be used to predict pH and ΩAragonite from other float-measured parameters (temperature, salinity, pressure, nitrate, oxygen). These algorithms were trained using bottle measurements from high-quality repeat hydrographic GO-SHIP cruises. We obtained R2 values of 0.98 (pH) and 0.99 (ΩAragonite) and RMS errors of 0.007 (pH) and 0.052 (ΩAragonite) for data between 100-1500 m. These algorithms will allow us to both validate pH data from these sensors, as well as predict ΩAragonite and pH on floats that do not have pH sensors. Here we present estimated pH and ΩAragonite over 20 months of deployment for several SOCCOM floats in the Pacific Sector of the Southern Ocean. The results show seasonal ranges in surface pH and ΩAragonite of 0.05 and 0.1, respectively.

  4. Conceptual Design of Navy Floating Pier.

    Science.gov (United States)

    1982-09-01

    hurricane winds of 90 mph were assumed to act conurrently with storm crents of 6 knots. The current profile was assumed as linear from 6 knots at the and...Using 1982 dollars, the replacement cost for a fendering system is about $200/ linear ft. or $500,000. The prorated yearly cost is $100,000 per year...TwFto’ R) F. 1APPINNUIATIIF 0~A 0. 04_ _ _ @ COMPARTMENIT LOST TOW tonCALCLATIS pen w A~qT C~hAAATW FT9 FL OD 5.~ III 1 ®ACLAM owswe TAMU to"V ( ACUAT

  5. Floating Collection in an Academic Library: An Audacious Experiment That Succeeded

    Science.gov (United States)

    Coopey, Barbara; Eshbach, Barbara; Notartomas, Trish

    2016-01-01

    Can a floating collection thrive in a large multicampus academic research library? Floating collections have been successful in public libraries for some time, but it is uncommon for academic libraries and unheard of for a large academic library system. This article will discuss the investigation into the feasibility of a floating collection at…

  6. Sabrewing: A lightweight architecture for combined floating-point and integer arithmetic

    NARCIS (Netherlands)

    Bruintjes, Tom; Walters, K.H.G.; Gerez, Sabih H.; Molenkamp, Egbert; Smit, Gerardus Johannes Maria

    In spite of the fact that floating-point arithmetic is costly in terms of silicon area, the joint design of hardware for floating-point and integer arithmetic is seldom considered. While components like multipliers and adders can potentially be shared, floating-point and integer units in

  7. Separating Internal Waves and Vortical Motions: Analysis of LatMix -EM-APEX Float Measurements

    Science.gov (United States)

    2015-09-30

    absolute velocity using GPS fixes for every surfacing of the floats and compared the processed absolute velocities to nearby ADCP shipboard data for...rate. The floats were programmed to rise to the surface at the same time. In addition to Slocum gliders and Lagrangian floats, three-ship ADCP , S, T

  8. Floating frame grounding system. [for wind tunnel static force measurement

    Science.gov (United States)

    Forsyth, T. J.

    1987-01-01

    The development of a floating frame grounding system (FFGS) for the 40- by 80-foot low speed wind tunnel facility at the NASA Ames Research Center National Full Scale Aerodynamics Complex is addresssed. When electrical faults are detected, the FFGS ensures a ground path for the fault current. In addition, the FFGS alerts the tunnel operator when a mechanical foul occurs.

  9. Udpegning af potentielle sorte pletter via floating car data

    DEFF Research Database (Denmark)

    Splid Svendsen, Martin; Tradisauskas, Nerius; Lahrmann, Harry

    2008-01-01

    Formålet med dette paper er at undersøge, om det er muligt at udpege potentielle sorte pletter via floating car data. Der er i projektet udført teoretiske litteraturstudier for at skabe et grundlag for det senere analysearbejde, som danner baggrund for analysearbejdet. Dataene stammer fra Aalborg...

  10. Design Optimization and Evaluation of Gastric Floating Matrix Tablet ...

    African Journals Online (AJOL)

    HP

    CP934P polymers for floating and release rate control. Sodium bicarbonate was added as a gas-generating agent (CO2) in the presence of gastric fluid. Glipizide was mixed with the required quantities of HPMC K4M, CP 934P and. Sodium bicarbonate by geometric mixing then mixture was blended with microcrystalline.

  11. Floating greenhouses : an expert system for integral design

    NARCIS (Netherlands)

    Bakker, J.C.; Boer, de S.B.; Meijer, J.P.R.; Leppers, R.F.L.; Ruiter, de M.J.; Zevenbergen, C.

    2005-01-01

    The main advantages of floating greenhouses compared to greenhouses on solid ground are the possibilities for multiple use of space and for energy saving. As in the coming years large area¿s in the Netherlands will be necessary to create water storage, the capability to give these areas an

  12. A floating trap for sampling downstream migrant fishes.

    Science.gov (United States)

    Carl E. McLemore; Fred H. Everest; William R. Humphreys; Mario F. Solazzi

    1989-01-01

    Fishery scientists and managers are interested in obtaining information about downstream movements of fish species for biological and economic reasons. Different types of nets and traps have been used for this purpose with only partial success. The floating, self-cleaning downstream migrant trap described here proved successful for sampling several salmoniform and...

  13. Development of the floating sulphur biofilm reactor for sulphide ...

    African Journals Online (AJOL)

    driniev

    The formation of floating sulphur biofilm was observed in the microbial ecology studies of tannery ponds undertaken by the. Environmental Biotechnology Group at Rhodes University. This was related to the steep Redox gradients established at the air/ water interface of anaerobic, organically loaded and actively sulphate ...

  14. An Asynchronous IEEE Floating-Point Arithmetic Unit

    Directory of Open Access Journals (Sweden)

    Joel R. Noche

    2007-12-01

    Full Text Available An asynchronous floating-point arithmetic unit is designed and tested at the transistor level usingCadence software. It uses CMOS (complementary metal oxide semiconductor and DCVS (differentialcascode voltage switch logic in a 0.35 µm process using a 3.3 V supply voltage, with dual-rail data andsingle-rail control signals using four-phase handshaking.Using 17,085 transistors, the unit handles single-precision (32-bit addition/subtraction, multiplication,division, and remainder using the IEEE 754-1985 Standard for Binary Floating-Point Arithmetic, withrounding and other operations to be handled by separate hardware or software. Division and remainderare done using a restoring subtractive algorithm; multiplication uses an additive algorithm. Exceptionsare noted by flags (and not trap handlers and the output is in single-precision.Previous work on asynchronous floating-point arithmetic units have mostly focused on single operationssuch as division. This is the first work to the authors' knowledge that can perform floating-point addition,multiplication, division, and remainder using a common datapath.

  15. Experimental testing of moorings for large floating wave energy converters

    DEFF Research Database (Denmark)

    Thomsen, Jonas Bjerg; Ferri, Francesco; Kofoed, Jens Peter

    2016-01-01

    This paper presents the outcome of a test campaign, which investigates the behaviour of a synthetic mooring system applied to the Floating Power Plant wave energy converter. The study investigates the motion and tension response under operational and extreme sea states expected at the deployment ...

  16. Development and Evaluation of Floating Microspheres of Curcumin

    African Journals Online (AJOL)

    The shape and surface morphology of the microspheres were characterised by optical and scanning electron microscopy. Result: The floating microspheres showed particle size, buoyancy, drug entrapment efficiency and yield in the ranges of 251 - 387 µm, 74.6 - 90.6 %, and 72.6 - 83.5 %, and 45.5 - 82.0 %, respectively.

  17. The effect of floating houses on water quality

    NARCIS (Netherlands)

    M. Rutten; R. Lima; R. de Graaf; E. Foka; ir. Floris Boogaard; N. van de Giesen

    2015-01-01

    The need of an adaptive sustainable solution for the increased land scarcity, growing urbanization, climate change and flood risks resulted in the concept of the floating urbanization. In The Netherlands this new type of housing attracted the interest of local authorities, municipalities and water

  18. Floating knee: epidemiology and results of treatment | Abalo ...

    African Journals Online (AJOL)

    According to Fraser's classification, there were 21 type I, 10 type IIa, 7 type IIb, and 5 type IIc. Most of the floating knee injuries were treated with antegrade intramedullary nailing for both the femur and tibia. The mean follow up was 24.8 months. All the fractures united within a reasonable time except for three femur and 14 ...

  19. A global inventory of small floating plastic debris

    NARCIS (Netherlands)

    Van Sebille, Erik|info:eu-repo/dai/nl/304831921; Wilcox, Chris; Lebreton, Laurent; Maximenko, Nikolai; Hardesty, Britta Denise; Van Franeker, Jan A.; Eriksen, Marcus; Siegel, David; Galgani, Francois; Law, Kara Lavender

    2015-01-01

    Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on the North

  20. A global inventory of small floating plastic debris

    NARCIS (Netherlands)

    Sebille, van Erik; Wilcox, Chris; Lebreton, Laurent; Maximenko, Nikolai; Hardesty, Britta Denise; Franeker, van J.A.; Eriksen, Marcus; Siegel, David; Galgani, F.; Law, Kara Lavender

    2015-01-01

    Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on

  1. Charging free floating shared cars in metropolitan areas

    NARCIS (Netherlands)

    van der Poel, Gijs; Tensen, Tim; van Goeverden, Tom; van den Hoed, Robert

    2017-01-01

    This paper analyses the effect of two new developments: electrification and ‘free floating’ car sharing and their impact on public space. Contrary to station based shared cars, free floating cars do not have dedicated parking or charging stations. They therefore park at public parking spots and

  2. Life cycle assessment of a floating offshore wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Weinzettel, Jan [Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Technicka 2, Praha 166 27 (Czech Republic); Charles University in Prague Environment Center, U Krize 8, Prague 158 00 (Czech Republic); Reenaas, Marte; Solli, Christian [Industrial Ecology Programme, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Hertwich, Edgar G. [Industrial Ecology Programme, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)

    2009-03-15

    A development in wind energy technology towards higher nominal power of the wind turbines is related to the shift of the turbines to better wind conditions. After the shift from onshore to offshore areas, there has been an effort to move further from the sea coast to the deep water areas, which requires floating windmills. Such a concept brings additional environmental impact through higher material demand. To evaluate additional environmental burdens and to find out whether they can be rebalanced or even offset by better wind conditions, a prospective life cycle assessment (LCA) study of one floating concept has been performed and the results are presented in this paper. A comparison with existing LCA studies of conventional offshore wind power and electricity from a natural gas combined cycle is presented. The results indicate similar environmental impacts of electricity production using floating wind power plants as using non-floating offshore wind power plants. The most important stage in the life cycle of the wind power plants is the production of materials. Credits that are connected to recycling these materials at the end-of-life of the power plant are substantial. (author)

  3. Children's Typically-Perceived-Situations of Floating and Sinking

    Science.gov (United States)

    Joung, Yong Jae

    2009-01-01

    The purpose of this study is to explore children's typically-perceived-situations (TPS) of "floating" and "sinking". TPS refers to the situation rising spontaneously in an individual's mind when they first think of a phenomenon or concept. Data were collected from 148 Year 5 Korean children. As a result of analysing the data…

  4. Determination of bacterial and fungal numbers in floats of pre ...

    African Journals Online (AJOL)

    This study was aimed at determining the numbers of bacteria and fungi in the floats of main soaking, liming, deliming-bating, degreasing and pickling stages. To this end, the numbers of total aerobic mesophilic, proteolytic, lipolytic and aerobic spore-forming bacteria and, the numbers of total aerobic fungi (yeast and mould), ...

  5. On Hydroelastic Body-Boundary Condition of Floating Structures

    DEFF Research Database (Denmark)

    Xia, Jinzhu

    1996-01-01

    A general linear body boundary condition of hydroelastic analysis of arbitrary shaped floating structures generalizes the classic kinematic rigid-body (Timman-Newman) boundary condition for seakeeping problems. The new boundary condition is consistent with the existing theories under certain...

  6. Observation of floating potential asymmetry in the edge plasma of ...

    Indian Academy of Sciences (India)

    Floating potential; vertical magnetic field; vertical electric field reversal; vertical electric field reversal time. PACS No. 52.55.F. 1. Introduction. The motion of plasma in a toroidal magnetic field leads to a separation of charge particles through charge dependent toroidal drifts. This creates a vertical electric field which along.

  7. Design And Testing of The Floating Potential Probe For ISS

    Science.gov (United States)

    Hillard, G. Barry; Ferguson, Dale C.

    2001-01-01

    Flight 4A was an especially critical mission for the International Space Station (ISS). For the first time, the high voltage solar arrays generated significant amounts of power and long predicted environmental interactions (high negative floating potential and concomitant dielectric charging) became serious concerns. Furthermore, the same flight saw the Plasma Contacting Unit (PCU) deployed and put into operation to mitigate and control these effects. The ISS program office has recognized the critical need to verify, by direct measurement, that ISS does not charge to unacceptable levels. A Floating Potential Probe (FPP) was therefore deployed on ISS to measure ISS floating potential relative to the surrounding plasma and to measure relevant plasma parameters. The primary objective of FPP is to verify that ISS floating potential does not exceed the specified level of 40 volts with respect to the ambient. Since it is expected that in normal operations the PCU will maintain ISS within this specification, it is equivalent to say that the objective of FPP is to monitor the functionality of the PCU. In this paper, we report on the design and testing of the ISS FPP. In a separate paper, the operations and results obtained so far by the FPP will be presented.

  8. Development of the floating sulphur biofilm reactor for sulphide ...

    African Journals Online (AJOL)

    Development of the floating sulphur biofilm reactor for sulphide oxidation in biological water treatment systems. ... water interface of anaerobic, organically loaded and actively sulphate reducing systems. ... The effect of influent sulphide concentrations, flow rate and reactor dimensions on the sulphur biofilm formation were

  9. The floating knee: epidemiology, prognostic indicators & outcome following surgical management.

    Science.gov (United States)

    Rethnam, Ulfin; Yesupalan, Rajam S; Nair, Rajagopalan

    2007-11-26

    Floating Knee injuries are complex injuries. The type of fractures, soft tissue and associated injuries make this a challenging problem to manage. We present the outcome of these injuries after surgical management. 29 patients with floating knee injuries were managed over a 3 year period. This was a prospective study were both fractures of the floating knee injury were surgically fixed using different modalities. The associated injuries were managed appropriately. Assessment of the end result was done by the Karlstrom criteria after bony union. The mechanism of injury was road traffic accident in 27/29 patients. There were 38 associated injuries. 20/29 patients had intramedullary nailing for both fractures. The complications were knee stiffness, foot drop, delayed union of tibia and superficial infection. The bony union time ranged from 15 - 22.5 weeks for femur fractures and 17 - 28 weeks for the tibia. According to the Karlstrom criteria the end results were Excellent - 15, Good - 11, Acceptable - 1 and Poor - 3. The associated injuries and the type of fracture (open, intra-articular, comminution) are prognostic indicators in the Floating knee. Appropriate management of the associated injuries, intramedullary nailing of both the fractures and post operative rehabilitation are necessary for good final outcome.

  10. Hydrodynamic analysis of elastic floating collars in random waves

    Science.gov (United States)

    Bai, Xiao-dong; Zhao, Yun-peng; Dong, Guo-hai; Li, Yu-cheng

    2015-06-01

    As the main load-bearing component of fish cages, the floating collar supports the whole cage and undergoes large deformations. In this paper, a mathematical method is developed to study the motions and elastic deformations of elastic floating collars in random waves. The irregular wave is simulated by the random phase method and the statistical approach and Fourier transfer are applied to analyze the elastic response in both time and frequency domains. The governing equations of motions are established by Newton's second law, and the governing equations of deformations are obtained based on curved beam theory and modal superposition method. In order to validate the numerical model of the floating collar attacked by random waves, a series of physical model tests are conducted. Good relationship between numerical simulation and experimental observations is obtained. The numerical results indicate that the transfer function of out-of-plane and in-plane deformations increase with the increasing of wave frequency. In the frequency range between 0.6 Hz and 1.1 Hz, a linear relationship exists between the wave elevations and the deformations. The average phase difference between the wave elevation and out-of-plane deformation is 60° with waves leading and the phase between the wave elevation and in-plane deformation is 10° with waves lagging. In addition, the effect of fish net on the elastic response is analyzed. The results suggest that the deformation of the floating collar with fish net is a little larger than that without net.

  11. Automated ''float'' method for determination of densities of molten salts

    DEFF Research Database (Denmark)

    Andreasen, Helge A.; Bjerrum, Niels; Foverskov, Carl Erik

    1977-01-01

    wound with platinum wire, an amplifier, a digital voltmeter, an interface, a paper tape punch, and a recorder. The advantages of the system are its ease of operation compared to other ''float'' methods, and the possibility of looking at highly colored melts and also melts having a high vapor pressure...

  12. Formulation and Evaluation of Gastro-retentive Floating Multi ...

    African Journals Online (AJOL)

    Purpose: To develop a floating multiparticulate unit system for metoprolol tartarate, using a porous carrier, with an outcome for delayed gastric emptying. Methods: Dried microparticles of metoprolol tartarate were prepared by solvent evaporation using Eudragit® RS-PO, polypropylene foam powder, and dichloromethane as ...

  13. Informed floating voters? : The impact of media on electoral volatility

    NARCIS (Netherlands)

    Geers, S.

    2017-01-01

    In the last decades the number of floating voters has risen in many democracies and particularly in the Netherlands. Although media is likely to influence electoral volatility, it has often been neglected as a possible explanation for vote switching. Therefore, this dissertation examines how

  14. Research on heat transfer characteristic of crude oil during the tubular heating process in the floating roof tank

    Directory of Open Access Journals (Sweden)

    Jian Zhao

    2017-09-01

    Full Text Available By means of finite volume method, the heat transfer characteristic of crude oil under the tubular heating in the floating roof tank is investigated by numerical simulation. The evolution of temperature profile and its relationship with the flow pattern is presented in detail. A noticeable finding is that there exists the transformation of the flow pattern which affects the temperature profile apparently during the heating process. Special concern is taken on the evolution of temperature distribution on the interface between oil and the inner wall of the tank. The temperature profile on the top wall, sidewall and base wall of the tank is investigated. It is concluded that the plume induced by natural convection takes most responsibility for the formation of temperature field in the tank. The second factor is the boundary condition of the tank.

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Floating plastic debris in the Central and Western Mediterranean Sea.

    Science.gov (United States)

    Ruiz-Orejón, Luis F; Sardá, Rafael; Ramis-Pujol, Juan

    2016-09-01

    In two sea voyages throughout the Mediterranean (2011 and 2013) that repeated the historical travels of Archduke Ludwig Salvator of Austria (1847-1915), 71 samples of floating plastic debris were obtained with a Manta trawl. Floating plastic was observed in all the sampled sites, with an average weight concentration of 579.3 g dw km(-2) (maximum value of 9298.2 g dw km(-2)) and an average particle concentration of 147,500 items km(-2) (the maximum concentration was 1,164,403 items km(-2)). The plastic size distribution showed microplastics (plastic in the entire Mediterranean region, with various potential spatial accumulation areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Floating Marine Debris in waters of the Mexican Central Pacific.

    Science.gov (United States)

    Díaz-Torres, Evelyn R; Ortega-Ortiz, Christian D; Silva-Iñiguez, Lidia; Nene-Preciado, Alejandro; Orozco, Ernesto Torres

    2017-02-15

    The presence of marine debris has been reported recently in several oceans basins; there is very little information available for Mexican Pacific coasts, however. This research examined the composition, possible sources, distribution, and density of Floating Marine Debris (FMD) during nine research surveys conducted during 2010-2012 in the Mexican Central Pacific (MCP). Of 1820 floating objects recorded, 80% were plastic items. Sources of FMD were determined using key objects, which indicated that the most were related to the presence of the industrial harbor and of a growing fishing industry in the study area. Densities were relatively high, ranging from 40 to 2440objects/km 2 ; the highest densities were recorded in autumn. FMD were distributed near coastal regions, mainly in Jalisco, influenced by river outflow and surface currents. Our results seem to follow worldwide trends and highlight the need for further studies on potential ecological impacts within coastal waters of the MCP. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Comparative Measurements of Indoor Radon in Homes and Floating Houses

    International Nuclear Information System (INIS)

    Changmuang, Wirote; Tantawiroon, Malulee; Polphong, Pornsri

    2003-06-01

    A survey of the radon ( 222 Rn) concentrations in 318 homes and 152 floating houses (1410 samples) in Phitsanulok province, using a passive 222 Rn charcoal canister and measurement by gamma spectrometry. Floating houses showed significant lower mean levels (8.22 Bqm -3 ) than homes (21.56 Bqm -3 ) (p 222 Rn concentrations indicated that concrete homes had a higher level than wooden homes and homes lying on ground had a higher level than those built at 1 meter or more above ground. The estimated annual mean effective dose equivalent 0.35 mSvy -1 and the annual lung dose equivalent of 5.94 mSvy -1 were only one-third of the world mean estimates

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

    Science.gov (United States)

    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.

  1. A floating water bridge produces water with excess charge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Sammer, Martina; Wexler, Adam D; Kuntke, Philipp; Woisetschläger, Jakob

    2016-01-01

    Excess positive and negative Bjerrum-defect like charge (protonic and ‘aterprotonic’, from ancient Greek ατερ, ‘without’) in anolyte and catholyte of high voltage electrolysis of highly pure water was found during the so-called ‘floating water bridge’ experiment. The floating water bridge is a special case of an electrohydrodynamic liquid bridge and constitutes an intriguing phenomenon that occurs when a high potential difference (∼kV cm −1 ) is applied between two beakers of water. To obtain such results impedance spectroscopy was used. This measurement technique allows the depiction and simulation of complex aqueous systems as simple electric circuits. In the present work we show that there is an additional small contribution from the difference in conductivity between anolyte and catholyte which cannot be measured with a conductivity meter, but is clearly visible in an impedance spectrum. (paper)

  2. Neutron scattering of a floating heavy water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Bitschnau, Brigitte; Woisetschlaeger, Jakob; Maier, Eugen; Beuneu, Brigitte; Teixeira, Jose

    2009-01-01

    When high voltage is applied to distilled water filled into two beakers close to each other, a water connection forms spontaneously, giving the impression of a floating water bridge (Fuchs et al 2007 J. Phys. D: Appl. Phys. 40 6112-4, 2008 J. Phys. D: Appl. Phys. 41 185502). This phenomenon is of special interest, since it comprises a number of phenomena currently tackled in modern water science. In this work, the first data on neutron scattering of a floating heavy water bridge are presented and possible interpretations are discussed. D 2 O was measured instead of H 2 O because of the very strong incoherent scattering of H. The obtained data support the 'bubble hypothesis' suggested earlier (Fuchs et al 2008).

  3. A floating water bridge produces water with excess charge

    Science.gov (United States)

    Fuchs, Elmar C.; Sammer, Martina; Wexler, Adam D.; Kuntke, Philipp; Woisetschläger, Jakob

    2016-03-01

    Excess positive and negative Bjerrum-defect like charge (protonic and ‘aterprotonic’, from ancient Greek ἄ'τɛρ, ‘without’) in anolyte and catholyte of high voltage electrolysis of highly pure water was found during the so-called ‘floating water bridge’ experiment. The floating water bridge is a special case of an electrohydrodynamic liquid bridge and constitutes an intriguing phenomenon that occurs when a high potential difference (~kV cm-1) is applied between two beakers of water. To obtain such results impedance spectroscopy was used. This measurement technique allows the depiction and simulation of complex aqueous systems as simple electric circuits. In the present work we show that there is an additional small contribution from the difference in conductivity between anolyte and catholyte which cannot be measured with a conductivity meter, but is clearly visible in an impedance spectrum.

  4. Floating and flying ferrofluid bridges induced by external magnetic fields

    Science.gov (United States)

    Ma, Rongchao; Zhou, Yixin; Liu, Jing

    2015-04-01

    A ferrofluid is a mixture that exhibits both magnetism and fluidity. This merit enables the ferrofluid to be used in a wide variety of areas. Here we show that a floating ferrofluid bridge can be induced between two separated boards under a balanced external magnetic field generated by two magnets, while a flying ferrofluid bridge can be induced under an unbalanced external magnetic field generated by only one magnet. The mechanisms of the ferrofluid bridges were discussed and the corresponding mathematical equations were also established to describe the interacting magnetic force between the ferro particles inside the ferrofluid. This work answered a basic question that, except for the well-known floating water bridges that are related to electricity, one can also build up a liquid bridge that is related to magnetism.

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

    International Nuclear Information System (INIS)

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

    2015-01-01

    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. (paper)

  6. Effect of combined ecological floating bed for eutrophic lake remediation

    Science.gov (United States)

    Zheng, Liguo; Wang, Haiping

    2017-05-01

    A novel combined ecological floating bed(CEFB) integrated high-density hydrophyte and aquatic animals, the wave-making equipments, water cycling automatic aerators and fluorescence inducing equipments. The water quality of a eutrophic lake was improved significantly after three months remediation of CEFB. Compared with the background value, the results showed that the removal efficiencies of total nitrogen (TN), ammonia(NH3-N), total phosphorous(TP) and chemical oxygen demand (COD) in the water reached 31.5%, 33%, 30.5% and 53%, respectively. CEFB could manipulate biotic interactions in the aquatic ecosystem, and then absorb eutrophic material efficiently by the co-effect of floating the sediment slowly, refreshing the static eutrophic water body, changing the photosynthetic and biochemical environment of the eutrophic water body and inducing plankton directional movement. At the same time, plants and fish grew good in CEFB,which can bring economic income to some extent.

  7. Pattern transitions in a compressible floating elastic sheet.

    Science.gov (United States)

    Oshri, Oz; Diamant, Haim

    2017-09-13

    Thin rigid sheets floating on a liquid substrate appear, for example, in coatings and surfactant monolayers. Upon uniaxial compression the sheet undergoes transitions from a compressed flat state to a periodic wrinkled pattern to a localized folded pattern. The stability of these states is determined by the in-plane elasticity of the sheet, its bending rigidity, and the hydrostatics of the underlying liquid. Wrinkles and folds, and the wrinkle-to-fold transition, were previously studied for incompressible sheets. In the present work we extend the theory to include finite compressibility. We analyze the details of the flat-to-wrinkle transition, the effects of compressibility on wrinkling and folding, and the compression field associated with pattern formation. The state diagram of the floating sheet including all three states is presented.

  8. Predicting vehicle fuel consumption patterns using floating vehicle data.

    Science.gov (United States)

    Du, Yiman; Wu, Jianping; Yang, Senyan; Zhou, Liutong

    2017-09-01

    The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were used. The fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers' information and vehicles' parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed respectively. The fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model. Copyright © 2017. Published by Elsevier B.V.

  9. Floating tumor debris. A cause of intermittent biliary obstruction.

    Science.gov (United States)

    Roslyn, J J; Kuchenbecker, S; Longmire, W P; Tompkins, R K

    1984-11-01

    Tumor debris, free-floating in the major biliary ductal system, is a cause of intermittent biliary obstruction that has previously not been recognized. Six patients had hepatic neoplasms with episodic jaundice and/or cholangitis due to floating tumor debris. Diagnosis included metastatic adenocarcinoma of the colon (n = 3), cholangiocarcinoma (n = 1), hepatocellular carcinoma (n = 1), and cavernous hemangioma (n = 1). All patients underwent biliary exploration, with hepatic resection and transhepatic intubation in two and T-tube placement in four. One patient died in the early postoperative period, and the major complication rate in the five survivors was 0%. Four of the five survivors had no further episodes suggestive of major bile duct obstruction. Our experience emphasizes the importance of distinguishing extrahepatic obstruction secondary to tumor debris from the more common causes of jaundice in patients with tumors and suggests that safe and effective palliation can be achieved in these patients.

  10. Management of “floating elbow” in children

    Science.gov (United States)

    Suresh, SS

    2007-01-01

    Background: Supracondylar fractures associated with ipsilateral forearm fractures, aptly termed as “floating elbow” is a rare injury in children after a fall from height. The various authors have reported their results with conservative treatment of one or both injuries to aggressive emergency operative fixation of both components. Materials and Methods: During a period of three years, the author managed four cases of floating elbow in children. All cases were managed by closed reduction and pinning of both components of the injury. Results: All patients recovered full elbow range of motion at three months followup and were rated as excellent as per modified Flynn's criteria. None of the patients developed cubitus varus deformity, complications related to the pins or delayed union. Conclusions: Early closed reduction and K wire fixation of both components of this injury gives better stability and prevents development of complications like compartment syndrome and elbow deformities. PMID:21139796

  11. Free-floating magnetic microstructures by mask photolithography

    Science.gov (United States)

    Huong Au, Thi; Thien Trinh, Duc; Bich Do, Danh; Phu Nguyen, Dang; Cong Tong, Quang; Diep Lai, Ngoc

    2018-03-01

    This work explores the fabrication of free-floating magnetic structures on a photocurable nanocomposite consisting of superparamagnetic magnetite nanoparticles (Fe3O4) and a commercial SU-8 negative tone photoresist. The nanocomposite was synthesized by mixing magnetic nanoparticles with different kinds of SU-8 resin. We demonstrated that the dispersion of Fe3O4 nanoparticles in nanocomposite solution strongly depended on the particles concentration, the viscosity of SU-8 polymer, and the mixing time. The influence of these factors was demonstrated by examining the structures fabricated by mask photolithography technique. We obtained the best quality of structures at a low concentration, below 5 wt%, of Fe3O4 nanoparticles in SU-8 2005 photoresist for a mixing time of about 20 days. The manipulation of free-floating magnetic microstructures by an external magnetic field was also demonstrated showing promising applications of this magnetic nanocomposite.

  12. Exposure fire protection for floating nuclear power plants

    International Nuclear Information System (INIS)

    Caines, R.E.

    1975-01-01

    It is stressed that the development of a nuclear power plant that will float on water, yet will remain in a stationary position, requires a reassessment of the type of protection available for exposure protection. The function of the external fire protection system designed to extinguish or control combustible liquid fires within the basin area and protect the plant against radiant heat fluxes from exposure fires more than 100 feet from the plant is discussed. 6 refs

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

    Science.gov (United States)

    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.

  14. Debate - Trafficking as a Floating Signifier: The view from Brazil

    OpenAIRE

    Grupo Davida

    2015-01-01

    The fact that the United Nations (UN) Trafficking Protocol is not an autochthonous product of the Brazilian political system has resulted in its being brought into that system as a ‘floating signifier’: something that does not point to any actual object or agreed upon meaning.[1] People who wish to criminalise prostitution have attempted to bend the Protocol in that direction while prostitutes’ rights groups have used it to critique current Brazilian laws, emphasising the need to distinguish ...

  15. Overcoming Fear of Floating: Exchange Rate Policies in Chile.

    OpenAIRE

    Jose De Gregorio; Andrea Tokman R.

    2004-01-01

    The paper reviews the exchange rate management experience in Chile, with particular emphasis on the floating exchange rate regime and its two forex intervention episodes. It presents evidence on Chile’s favorable conditions to face exchange rate shocks: a well-developed financial sector, that offers hedging opportunities taken up by the corporate sector to decrease its vulnerability through balance sheet effects; and a low and decreasing level of passthrough from the exchange rate to prices. ...

  16. The study to estimate the floating population in Seoul, Korea

    OpenAIRE

    Lee, Geon Woo; Lee, Yong Jin; Kim, Youngeun; Hong, Seung-Han; Kim, Soohwaun; Kim, Jeong Soo; Lee, Jong Tae; Shin, Dong Chun; Lim, Youngwook

    2017-01-01

    Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the o...

  17. Mature ovarian teratoma with large floating fat globules

    Energy Technology Data Exchange (ETDEWEB)

    Son, Hye Min; Kim, See Hyung; Hwang, Il Seon [Keimyung University School of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of)

    2016-04-15

    Mature ovarian teratoma (dermoid cyst), a germ cell neoplasm, is one of the most common ovarian tumors. It is composed of derivatives of three germ cell layers. A mature ovarian teratoma with intracystic fat globules is rare. The pathogenesis on the formation of fat globules is unclear. Here we present a pathologically proven cystic ovarian teratoma with three large floating fat globules in a young woman with CT and MR findings.

  18. Prospect of floating desalination facilities using nuclear energy in Indonesia

    International Nuclear Information System (INIS)

    Rusli, A.; Rina, G.; Gunandjar; Subki, I.R.

    1997-01-01

    This paper summarizes studies on the water demand and supply problems in Indonesia in the last few years. During the dry season in 1990, it was reported that lack of fresh drinking water in Java and Bali amounted to 2.4 x 10 6 ton/month. Since Indonesia consists of more than 13,000 islands, more problems are faced by other islands. The studies are focused on certain regions (groups of islands) which may have a potential for using a floating desalination facility. Water reservoirs in each island and delivery systems from the floating desalination facilities need to be assessed to see the prospective uses of the systems. Cheap, self-forgiving and easily operated systems, using transportable ship mounted desalination facilities, may be required as a solution to the water supply shortages for these islands. Conclusions based on current problems in water demand and supply and comments on the prospective future market using floating desalination facilities in Indonesia are also given. (author). 9 refs, 10 tabs

  19. Seismic response analysis of floating nuclear power plant

    International Nuclear Information System (INIS)

    Hagiwara, Yutaka; Nakamura, Hideharu; Shiojiri, Hiroo

    1988-01-01

    Since Floating Nuclear Power Plants (FNPs) are considered to be isolated from horizontal seismic motion, it is anticipated to reduce seismic load for plant components and buildings on the barge. On the other hand, barge oscillation and sloshing in the closed basin might be excited by earthquakes, because natural periods of those motions correspond to relatively-long period component (between 2 and 20 seconds) of seismic motion. Therefore, it is necessary to evaluate seismic isolation effects and barge oscillation, for the rational design of FNPs. However, there do not exist any reasonable analytical tools which can evaluate seismic response of floating structures in closed basin. The purpose of the present report is to develop a seismic analysis method for FNPs. The proposed method is based on the finite element method, and the formulation includes fluid-structure interaction, water surface wave, buoyancy effect, and non-linear characteristics of mooring system. Response analysis can be executed in both time-domain and frequency-domain. Shaking table tests were conducted to validate the proposed method of analysis. The test results showed significant isolation effect of floating structure, and apparent interaction between the barge and the basin. And 2-D and 3-D frequency domain analyses and the 2-D linear and non-linear time-domain analyses were done and those analyses could simulate the test results well. (author)

  20. On seismic response characteristics of floating nuclear plant barge, (2)

    International Nuclear Information System (INIS)

    Hagiwara, Yutaka; Masuko, Yosio; Kurihara, Chizuko; Sasaki, Shunji; Sakurai, Akio

    1987-01-01

    Though floating nuclear plants (FNPs) is effectively isolated from horizontal earthquake motion, vertical earthquake motion on FNPs is almost the same as the ground motion inevitably. Therefore an alternative design concept of FNPs has been developed, which is isolated from vertical earthquake motion as well, utilizing pneumatic chambers equipped to the bottom of the barge. In this report, a simple analytical solution, which describes the vertical earthquake response of a floating body which has pneumatic chambers below its bottom, is derived. And a shaking table test and an earthquake response observation of floating bodies with pneumatic chambers are conducted to verify the solution. The prediction by the analytical solution gives sufficient agreement with the experimental results, so that the solution is confirmed to be valid. Then the fundamental geometry of a FNP barge with pneumatic chambers is assumed, and finally, it is evaluated by the solution that high-frequency ( ≥ 1 Hz) vertical acceleration on the barge induced by vertical component of earthquakes, will be reduced to approximately, a quater of the ground motion. (author)

  1. In vitro Evaluation of Acyclovir/Chitosan Floating Systems.

    Science.gov (United States)

    Ruiz-Caro, Roberto; Veiga, María D

    2010-12-06

    Chitosan (CS) floating lyophilized formulations (L) for gastric drug delivery of acyclovir (ACV) have been developed. The freeze-dried formulations were obtained from acidic aqueous suspensions prepared with different ACV/CS ratios. No changes in ACV crystallinity were observed during X-ray diffraction powder studies as a consequence of the manufacturing process. Considering that fed and fasted states modified the intragastric pH, swelling and in vitro dissolution studies were carried out in different acidic media (0.1 M HCl and progressive pH medium) in order to understand the influence of these physiological states on ACV/CS formulations. Swelling behavior of the floating lyophilized formulations was dependent on CS and ACV proportions within L and on medium nature due to pH dependent CS solubility. Furthermore, no interactions between ACV and CS were detected in solid state according to the X-ray studies. In vitro dissolution of ACV from L was influenced by the swelling behavior. However, it is feasible to optimize the ACV/CS ratios to achieve a desired formulation that releases the total quantity of ACV at a specific time. Moreover, floatability was assessed by buoyancy tests. The results demonstrated that the freeze-drying process achieved effective floating systems capable of remaining within the stomach while the total amount of ACV is released from L.

  2. Water Pressure Distribution on a Twin-Float Seaplane

    Science.gov (United States)

    Thompson, F L

    1930-01-01

    This is the second of a series of investigations to determine water pressure distribution on various types of seaplane floats and hulls, and was conducted on a twin-float seaplane. It consisted of measuring water pressures and accelerations on a TS-1 seaplane during numerous landing and taxiing maneuvers at various speeds and angles. The results show that water pressures as great as 10 lbs. per sq. in.may occur at the step in various maneuvers and that pressures of approximately the same magnitude occur at the stern and near the bow in hard pancake landings with the stern way down. At the other parts of the float the pressures are less and are usually zero or slightly negative for some distance abaft the step. A maximum negative pressure of 0.87 lb. Per square inch was measured immediately abaft the step. The maximum positive pressures have a duration of approximately one-twentieth to one-hundredth second at any given location and are distributed over a very limited area at any particular instant.

  3. Experimental investigation of the stability of the floating water bridge

    Science.gov (United States)

    Montazeri Namin, Reza; Azizpour Lindi, Shiva; Amjadi, Ahmad; Jafari, Nima; Irajizad, Peyman

    2013-09-01

    When a high voltage is applied between two beakers filled with deionized water, a floating bridge of water is formed in between exceeding the length of 2 cm when the beakers are pulled apart. Currently two theories regarding the stability of the floating water bridge exist, one suggesting that the tension caused by electric field in the dielectric medium is holding the bridge and the other suggesting surface tension to be responsible for the vertical equilibrium. We construct experiments in which the electric field and the geometry of the bridge are measured and compared with predictions of theories of the floating water bridge stability. We use a numerical simulation for estimation of the electric field. Our results indicate that the two forces of dielectric and surface tensions hold the bridge against gravity simultaneously and, having the same order of magnitude, neither of the two forces are negligible. In bridges with larger diameters, the effect of dielectric tension is slightly more in the vertical equilibrium than surface tension. Results show that the stability can be explained by macroscopic forces, regardless of the microscopic changes in the water structure.

  4. Performance of floating oil booms in unsheltered waters

    Science.gov (United States)

    Iglesias, Gregorio; Castro, Alberte

    2013-04-01

    Oil booms are a fundamental tool to diminish the impact of an oil spill. They tend to perform reasonably well in sheltered waters, e.g. within a harbour. However, their performance is often inadequate in open water conditions, under waves, winds and currents. And it is precisely in those conditions that they are needed if oil slicks are to be prevented from reaching certain particularly sensitive areas, such as estuaries, rias, etc. (Castro et al., 2010; Iglesias et al., 2010). In this work the performance of floating oil booms under waves and currents is assessed on the basis of laboratory experiments carried out in a state-of-the-art wave-current flume. Different oil boom models are used, representative of booms with long and short skirts and with different weights. The results show that different booms behave very differently under waves and currents, hence the importance of selecting the boom design that is appropriate for the actual conditions under which it will have to contain the oil slick. Thus, different oil booms should be used for different areas. References A. Castro, G. Iglesias, R. Carballo, J.A. Fraguela, 2010. Floating boom performance under waves and currents, Journal of Hazardous Materials 174, 226-235 G. Iglesias, A.Castro, J.A.Fraguela, 2010. Artificial intelligence applied to floating boom behavior under waves and currents, Ocean Engineering 37, 1513-1521.

  5. Computational fluid dynamic analysis for independent floating water treatment device

    Science.gov (United States)

    Zawawi, M. H.; Swee, M. G.; Zainal, N. S.; Zahari, N. M.; Kamarudin, M. A.; Ramli, M. Z.

    2017-09-01

    This project is to design and develop 3D Independent Floating Water Treatment Device using 3D CAD software. The device is designed to treat water for better water qualities and water flows of the lakes. A prototype was manufactured to study the water treatment efficiency of the device. Computational Fluid Dynamic (CFD) analysis was used to capture the efficiency of the Independent Floating Water Treatment Device by simulates and model the water flows, pressure and velocity. According to the results, the maximum velocity magnitude was around 1m3/s. The velocity contour showed the device has high velocity at the pipe outlet. The velocity became lower and lower as the distance is further from the pipe outlet. The result from the velocity measurement was 1.05m/s. The pressure magnitude was in between 1426 Pa to 1429 Pa. The laboratory results based on water parameters proved that the water movement and direction of water flow of the Independent Floating Water Treatment Device enable the efficient pollutant removal. The vector plot, velocity contour, water flow path lines, water flow streamline and pressure contour was successful modeled.

  6. Floating-to-Fixed-Point Conversion for Digital Signal Processors

    Directory of Open Access Journals (Sweden)

    Menard Daniel

    2006-01-01

    Full Text Available Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.

  7. Pharmacoscintigraphic and pharmacokinetic evaluation on healthy human volunteers of sustained-release floating minitablets containing levodopa and carbidopa.

    Science.gov (United States)

    Goole, J; Van Gansbeke, B; Pilcer, G; Deleuze, Ph; Blocklet, D; Goldman, S; Pandolfo, M; Vanderbist, F; Amighi, K

    2008-11-19

    In this study, scintigraphic and pharmacokinetic studies were conducted on 10 healthy, fed volunteers. Two concepts of sustained-release floating minitablets--Levo-Form 1 (matrix) and 2 (coated)--were evaluated and compared to the marketed product Prolopa HBS 125. All the floating forms were radiolabelled with (111)In in order to evaluate their gastric residence time using gamma-scintigraphy. It was shown that the three formulations offered almost the same mean gastric residence time, which was about 240 min. Prolopa HBS 125 and Levo-Form 2 presented intragastric disintegration, which can lead to a more pronounced "peak & valley" effect on the plasma concentration-time profile of levodopa. In contrast, the plasma concentration-time profile of levodopa following the administration of Levo-Form 1 was more evenly distributed. Moreover, Levo-Form 1 provided the lowest variations between men and women in terms of AUC and C(max) values. Finally, when the same amount of inhibitors of extracerebral dopa decarboxylase--carbidopa and benserazide--had been administrated, the mean AUC, C(max) and T(max) values obtained for benserazide were lower than those obtained for carbidopa.

  8. A Floating Ocean Energy Conversion Device and Numerical Study on Buoy Shape and Performance

    Directory of Open Access Journals (Sweden)

    Ruiyin Song

    2016-05-01

    Full Text Available Wave and current energy can be harnessed in the East China Sea and South China Sea; however, both areas are subject to high frequencies of typhoon events. To improve the safety of the ocean energy conversion device, a Floating Ocean Energy Conversion Device (FOECD with a single mooring system is proposed, which can be towed to avoid severe ocean conditions or for regular maintenance. In this paper, the structure of the FOECD is introduced, and it includes a catamaran platform, an oscillating buoy part, a current turbine blade, hydraulic energy storage and an electrical generation part. The numerical study models the large catamaran platform as a single, large buoy, while the four floating buoys were modeled simply as small buoys. Theoretical models on wave energy power capture and efficiency were established. To improve the suitability of the buoy for use in the FOECD and its power harvesting capability, a numerical simulation of the four buoy geometries was undertaken. The shape profiles examined in this paper are cylindrical, turbinate (V-shaped and U-shaped cone with cylinder, and combined cylinder-hemisphere buoys. Simulation results reveal that the suitability of a turbinate buoy is the best of the four types. Further simulation models were carried out by adjusting the tip radius of the turbinate buoy. Three performance criteria including suitability, power harvesting capability and energy capture efficiency were analyzed. It reveals that the turbinate buoy has almost the same power harvesting capabilities and energy capture efficiency, while its suitability is far better than that of a cylindrical buoy.

  9. Water flow and solute transport in floating fen root mats

    Science.gov (United States)

    Stofberg, Sija F.; EATM van der Zee, Sjoerd

    2015-04-01

    Floating fens are valuable wetlands, found in North-Western Europe, that are formed by floating root mats when old turf ponds are colonized by plants. These terrestrialization ecosystems are known for their biodiversity and the presence of rare plant species, and the root mats reveal different vegetation zones at a small scale. The vegetation zones are a result of strong gradients in abiotic conditions, including groundwater dynamics, nutrients and pH. To prevent irreversible drought effects such as land subsidence and mineralization of peat, water management involves import of water from elsewhere to maintain constant surface water levels. Imported water may have elevated levels of salinity during dry summers, and salt exposure may threaten the vegetation. To assess the risk of exposure of the rare plant species to salinity, the hydrology of such root mats must be understood. Physical properties of root mats have scarcely been investigated. We have measured soil characteristics, hydraulic conductivity, vertical root mat movement and groundwater dynamics in a floating root mat in the nature reserve Nieuwkoopse Plassen, in the Netherlands. The root mat mostly consists of roots and organic material, in which the soil has a high saturated water content, and strongly varies in its stage of decomposition. We have found a distinct negative correlation between degree of decomposition and hydraulic conductivity, similar to observations for bogs in the literature. Our results show that the relatively young, thin edge of the root mat that colonizes the surface water has a high hydraulic conductivity and floats in the surface water, resulting in very small groundwater fluctuations within the root mat. The older part of the root mat, that is connected to the deeper peat layers is hydrologically more isolated and the material has a lower conductivity. Here, the groundwater fluctuates strongly with atmospheric forcing. The zones of hydraulic properties and vegetation, appear to

  10. An algorithm for detecting trophic status (chlorophyll-a), cyanobacterial-dominance, surface scums and floating vegetation in inland and coastal waters

    CSIR Research Space (South Africa)

    Matthews, MW

    2012-09-01

    Full Text Available variable. This is supported by evidence that vacuolate cyanobacteria (e.g. Microcystis aeruginosa) possess enhanced chl-a specific backscatter which is an important bio-optical distinguishing feature. This enables these broad algal classes to be distinguish...

  11. Model predictive control for a dual active bridge inverter with a floating bridge

    OpenAIRE

    Chowdhury, Shajjad; Wheeler, Patrick W.; Gerada, C.; Patel, Chintan

    2016-01-01

    This paper presents a Model Predictive Control technique applied to a dual active bridge inverter where one of the bridges is floating. The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight and losses in the system. To achieve multilevel output voltage waveforms the floating inverter DC link capacitor is charged to the half of the main DC link voltage. A finite-set Model Predictive Control technique...

  12. IEEE-754 compliant Algorithms for Fast Multiplication of Double Precision Floating Point Numbers

    OpenAIRE

    Geetanjali Wasson

    2011-01-01

    In image and signal processing applications floating-point multiplication is major concern in calculations. Performing multiplication on floating point data is a long course of action and requires huge quantity of processing time. By improving the speed of multiplication task overall speed of the system can be enhanced. The Bottleneck in the floating point multiplication process is the multiplication of mantissas which needs 53*53 bit integer multiplier f...

  13. In vitro and in vivo evaluation of floating riboflavin pellets developed using the melt pelletization process.

    Science.gov (United States)

    Hamdani, J; Goole, J; Moës, A J; Amighi, K

    2006-10-12

    Floating pellets were prepared using the melt pelletization process in a Mi-Pro high shear mixer (Pro-C-epT, Belgium). Formulations were based on a mixture of Compritol and Precirol as meltable binders and on the use of sodium bicarbonate and tartaric acid as gas-generating agents. Good floating abilities were obtained by using the gas-generating agents in both the inner matrix and the outer coating layer of the pellets. In vitro evaluation of floating capability was performed both by using the resultant weight apparatus and by counting floating pellets at the surface of beakers containing 0.1N HCl solution, in vivo evaluation of floating pellets capabilities was also performed. Riboflavin-containing floating pellets (FRF) were administered orally to nine healthy volunteers versus non-floating pellets (NFRF). Volunteers were divided in two groups, fasted group (n=4) 729 kcal and fed group (n=5) 1634 kcal as the total calorie intake on the testing day. An increase of urinary excretion of riboflavin was observed when the volunteers were dosed with the floating pellets, especially after feeding. As riboflavin has a narrow window of absorption in the upper part of small intestine, this phenomenon could be attributable to the gastric retention of floating pellets.

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

    Science.gov (United States)

    Gschwind, Michael K [Chappaqua, NY

    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.

  15. Development and characterization of floating spheroids of atorvastatin calcium loaded NLC for enhancement of oral bioavailability.

    Science.gov (United States)

    Sharma, Kritika; Hallan, Supandeep Singh; Lal, Bharat; Bhardwaj, Ankur; Mishra, Neeraj

    2016-09-01

    The obejctive of the present study was to investigate the potential use of floating spheroids of Atorvastatin Calcium (ATS) Loaded nanostructured lipid carriers (NLCs). The final formula of floating spheroids was optimized on the basis of shape (spherical), diameter (0.47 mm), lag time (20 s), and floating time (> 32 h). The results were further confirmed by different pharmacokinetic parameters-it was observed that the developed optimized floating ATS spheroid-loaded NLCs formulation has significantly improved relative bioavailability, that is, 3.053-folds through oral route in comparison to marketed formulation.

  16. Extended onshore control of a floating wind turbine with wave disturbance reduction

    DEFF Research Database (Denmark)

    Christiansen, S.; Knudsen, T.; Bak, Thomas

    2014-01-01

    Reaching for higher wind resources floating wind turbines are being investigated. Wave induced loads significantly increase for floating wind turbines, and applying conventional onshore control strategies to floating wind turbines has been shown to impose negative damped oscillations in fore......-aft due to the low natural frequency of the floating structure. We suggest a control loop extension of the onshore controller which stabilizes the system and reduces the wave disturbance. The result is improved performance in power fluctuations, blade pitch activity, and platform oscillations...

  17. Fracture characterisation of float glass under static and dynamic loading

    Directory of Open Access Journals (Sweden)

    A. Nyounguè

    2016-12-01

    Full Text Available This paper presents the study of float glass fracture under static and dynamic loading, with the use of experimental and numerical fracture mechanics methods. It has been shown that the value of notch fracture toughness under static loading depends neither on the kind of test nor on specimen geometry. This makes it possible to replace the three-points-bending specimens with the Brazilian discs which are, under certain test conditions, simpler and convenient to study. For both types of specimens, an analysis of the fracture strength, the notch stress intensity factor and fragmentation of specimens was carried out.

  18. Extreme load predictions for floating offshore wind turbines

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2009-01-01

    An effective stochastic procedure for extreme value predictions related to wave and wind induced stochastic loads is applied to a tension-leg concept for floating offshore wind turbines. The method is based on the First Order Reliability Method (FORM) and as the procedure makes use of only short...... time-domain simulations all kinds of non-linearities can be included. The procedure has been used previously for wave induced loads and is in this note extended to combined wave and wind loads....

  19. Electronically Tunable Multi-Terminal Floating Nullor and Its Applications

    Directory of Open Access Journals (Sweden)

    W. Tangsrirat

    2008-12-01

    Full Text Available A realization scheme of an electronically tun- able multi-terminal floating nullor (ET-MTFN is de- scribed in this paper. The proposed circuit mainly employs a transconductance amplifier, an improved translinear cell, two complementary current mirrors with variable current gain and improved Wilson current mirrors, which provide an electronic tuning of the current gain. The va- lidity of the performance of the scheme is verified through PSPICE simulation results. Example applications employing the proposed ET-MTFN as an active element demonstrate that the circuit properties can be varied by electronic means.

  20. Fabrication of mesoscopic floating Si wires by introducing dislocations

    International Nuclear Information System (INIS)

    Motohashi, Mitsuya; Shimizu, Kazuya; Niwa, Masaaki; Suzuki, Toshiaki

    2014-01-01

    We fabricated a mesoscopic Si wire by introducing dislocations in a silicon wafer before HF anodization. The dislocations formed along the (111) crystal plane. The outline of the dislocation line was an inverted triangle. The resulting wire floated on a bridge girder and had a hybrid structure consisting of a porous layer and crystalline Si. The cross section of the wire had an inverted triangle shape. The wire formation mechanism is discussed in terms of carrier transport, crystal structure, and dislocation formation during anodization. (paper)

  1. Fabrication of mesoscopic floating Si wires by introducing dislocations

    Science.gov (United States)

    Motohashi, Mitsuya; Shimizu, Kazuya; Suzuki, Toshiaki; Niwa, Masaaki

    2014-12-01

    We fabricated a mesoscopic Si wire by introducing dislocations in a silicon wafer before HF anodization. The dislocations formed along the (111) crystal plane. The outline of the dislocation line was an inverted triangle. The resulting wire floated on a bridge girder and had a hybrid structure consisting of a porous layer and crystalline Si. The cross section of the wire had an inverted triangle shape. The wire formation mechanism is discussed in terms of carrier transport, crystal structure, and dislocation formation during anodization.

  2. A custom floating point format ADC for LHC calorimetry

    International Nuclear Information System (INIS)

    Hermel, V.; Lecoq, J.; Bohner, G.

    1996-01-01

    Due to their large dynamic range (in excess of 16 bits) signals from LHC calorimetry poses severe problems to the shaping and digitizing circuits. We are investigating a solution for an ADC based on a custom floating point format. Since the calorimeter precision is limited, the full dynamic range can be split into 8 positive sub-ranges and 5 negative ones, each with an 8 bits dynamic. The reduced number of bits (8 for the mantissa, 4 for the exponent and 1 for the sign) translates itself into a reduction of the power consumption both of the ADC and of the following digital filtering stages. (authors)

  3. The floating face: Garbo, photography and death masks

    OpenAIRE

    Henning, Michelle

    2017-01-01

    A number of writers have noted the influence of Ernst Benkard’s 1927 book of death masks, Das Ewige Antlitz, on Modernist artists and writers of the inter-war period. This article links it specifically to the emergence in the late 1920s of a very particular way of photographing people, termed here “the floating face”, which is epitomised in publicity portraits of Greta Garbo. It is suggested that this photographic convention is linked to changing attitudes associated with war, to the techniqu...

  4. Floating Carpets and the Delamination of Elastic Sheets

    KAUST Repository

    Wagner, Till J. W.

    2011-07-22

    We investigate the deformation of a thin elastic sheet floating on a liquid surface and subject to a uniaxial compression. We show that at a critical compression the sheet delaminates from the liquid over a finite region forming a delamination "blister." This blistering regime adds to the wrinkling and localized folding regimes that have been studied previously. The transition from wrinkled to blistered states occurs when delamination becomes energetically favorable compared with wrinkling. We determine the initial blister size and the evolution of blister size with continuing compression before verifying our theoretical results with experiments at a macroscopic scale. © 2011 American Physical Society.

  5. Experience in float over integrated deck -- Design and installation

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, J.H.; Naudin, J.C.

    1996-12-31

    Since early 1980, Technip-Geoproduction (TPG), as designer or as installation contractor, has been using with success the float over system UNIDECK-TPG for the transportation and installation of integrated decks for offshore platforms. The concept offers the advantages of significant savings in transportation and installation cost by minimizing the installation time and offshore hook-up and eliminating the need for a heavy lift derrick barge. The paper describes the technology used for the installation, the required engineering studies, the consequences of using such a concept on platform design and the selection of an appropriate barge size to be used.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  7. Underwater Shock Response Analysis of a Floating Vessel

    Directory of Open Access Journals (Sweden)

    J.E. van Aanhold

    1998-01-01

    Full Text Available The response of a surface vessel to underwater shock has been calculated using an explicit finite element analysis. The analysis model is two-dimensional and contains the floating steel structure, a large surrounding water volume and the free surface. The underwater shock is applied in the form of a plane shock wave and cavitation is considered in the analysis. Advanced computer graphics, in particular video animations, provide a powerful and indispensable means for the presentation and evaluation of the analysis results.

  8. High-resolution Vertical Profiling of Ocean Velocity and Water Properties Under Hurricane Frances in September 2004

    Science.gov (United States)

    Sanford, T. B.; D'Asarp, E. A.; Girton, J. B.; Price, J. F.; Webb, D. C.

    2006-12-01

    In ONR's CBLAST Hurricane research program observations were made of the upper ocean's response to Hurricane Frances. Three EM-APEX floats (velocity sensing versions of Webb Research APEX floats) and two Lagrangian floats were deployed north of Hispaniola from a C-130 aircraft ahead of Hurricane Frances in September 2004. The EM-APEX floats measured T, S and V over the upper 500 m starting about a day before the storm's arrival. The Lagrangian floats measured temperature and salinity while following the three- dimensional boundary layer turbulence in the upper 40 m. One EM-APEX float was directly under the track of the storm's eye, another EM-APEX and two Lagrangian floats went in about 50 km to the right of the track (where the surface winds are strongest) and the third float was about 100 km to the right. The EM-APEX floats profiled for 10 hours from the surface to 200 m, then continued profiling between 35 and 200 m with excursions to 500 m every half inertial period. After 5 days, the EM-APEX floats surfaced and transmitted the accumulated processed observations, then the floats profiled to 500 m every half inertial period until recovered early in October aided by GPS and Iridium. The float array sampled in unprecedented detail the upper-ocean turbulence, momentum, and salt and heat changes in response to the hurricane. The buildup of surface gravity waves in advance of the storm was also observed in the velocity profiles, with significant wave heights of up to 11 m. Rapid acceleration of inertial currents in the surface mixing layer (SML) to over 1 m/s stimulated vertical mixing by shear instability at the SML base, as indicated by low Richardson numbers and SML deepening from about 40 m to 120 m under the strongest wind forcing. Surface cooling of about 2.5 C was primarily due to the SML deepening and entrainment of colder water, with a small contribution from surface heat flux. Intense inertial pumping was observed under the eye, with vertical excursions of

  9. Functionalization of Carbon Nanofibres Obtained by Floating Catalyst Method

    Directory of Open Access Journals (Sweden)

    Adolfo Fernández

    2015-01-01

    Full Text Available The excellent physicochemical and electrical properties of carbon nanofibres (CNF combined with the possibility of being produced at industrial scale at reasonable costs have promoted the interest in their use in very diverse areas. However, there are still some drawbacks that must be solved in order to optimize their set of properties such as the presence of impurities or the imperfections in the crystalline structure. In this work, different modification treatments of CNFs produced by the floating catalyst method have been studied. Three types of modification processes have been explored that can be grouped as mechanical, thermal, and chemical functionalization processes. Mechanical processing has allowed solving the agglomeration problem related to CNFs produced by floating catalyst method and the resulting modified product ensures the secure handling of carbon nanofibres. Thermal and chemical treatments lead to purer and more crystalline products by removing catalyst impurities and amorphous carbon. Functionalization processes explored in this work open the possibility of customized posttreatment of carbon nanofibres according to the desired requirements.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Optimal Floating and Queuing Strategies: The Logic of Territory Choice.

    Science.gov (United States)

    Pen, Ido; Weissing, Franz J

    2000-04-01

    This is a response to a recent article by Hanna Kokko and William J. Sutherland (American Naturalist 152:354-366), who consider evolutionarily stable territory acceptance rules for animals that face the decision between settling on a poor territory now (which is then retained for life) or waiting for better habitat to become available later (taking a chance of dying before reproducing). In contrast to these authors, we argue that the evolutionarily stable threshold quality above which territories are acceptable does depend on whether individuals compete for a single territory (queuing) or for multiple territories (floating) and also on whether access to territories is determined by a hierarchy among waiting individuals. More specifically, we show the following: First, if the choice is between floating and settling, the evolutionarily stable acceptance threshold is such that threshold territories yield an expected lifetime reproductive success (LRS) of [Formula: see text], the survival probability of a floater. Second, if the choice is between queuing and settling, the evolutionarily stable threshold may correspond to any LRS between [Formula: see text] and unity. Third, the number of nonbreeding individuals in the population is maximized at a threshold of unity. In other words, the evolutionarily stable threshold does not maximize the nonbreeding fraction of the population. We argue that models of territory choice should carefully specify the mechanism of choice because some choice processes (e.g., indiscriminate habitat use above the threshold) do not admit an evolutionarily stable acceptance rule.

  12. Numerical simulation of floating bodies in extreme free surface waves

    Directory of Open Access Journals (Sweden)

    Z. Z. Hu

    2011-02-01

    Full Text Available In this paper, we use the in-house Computational Fluid Dynamics (CFD flow code AMAZON-SC as a numerical wave tank (NWT to study wave loading on a wave energy converter (WEC device in heave motion. This is a surface-capturing method for two fluid flows that treats the free surface as contact surface in the density field that is captured automatically without special provision. A time-accurate artificial compressibility method and high resolution Godunov-type scheme are employed in both fluid regions (air/water. The Cartesian cut cell method can provide a boundary-fitted mesh for a complex geometry with no requirement to re-mesh globally or even locally for moving geometry, requiring only changes to cut cell data at the body contour. Extreme wave boundary conditions are prescribed in an empty NWT and compared with physical experiments prior to calculations of extreme waves acting on a floating Bobber-type device. The validation work also includes the wave force on a fixed cylinder compared with theoretical and experimental data under regular waves. Results include free surface elevations, vertical displacement of the float, induced vertical velocity and heave force for a typical Bobber geometry with a hemispherical base under extreme wave conditions.

  13. Coupled Thermal Field of the Rotor of Liquid Floated Gyroscope

    Directory of Open Access Journals (Sweden)

    Wang Zhengjun

    2015-01-01

    Full Text Available Inertial navigation devices include star sensor, GPS, and gyroscope. Optical fiber and laser gyroscopes provide high accuracy, and their manufacturing costs are also high. Magnetic suspension rotor gyroscope improves the accuracy and reduces the production cost of the device because of the influence of thermodynamic coupling. Therefore, the precision of the gyroscope is reduced and drift rate is increased. In this study, the rotor of liquid floated gyroscope, particularly the dished rotor gyroscope, was placed under a thermal field, which improved the measurement accuracy of the gyroscope. A dynamic theory of the rotor of liquid floated gyroscope was proposed, and the thermal field of the rotor was simulated. The maximum stress was in x, 1.4; y, 8.43; min 97.23; and max 154.34. This stress occurred at the border of the dished rotor at a high-speed rotation. The secondary flow reached 5549 r/min, and the generated heat increased. Meanwhile, the high-speed rotation of the rotor was volatile, and the dished rotor movement was unstable. Thus, nanomaterials must be added to reduce the thermal coupling fluctuations in the dished rotor and improve the accuracy of the measurement error and drift rate.

  14. Fragility of Floating Docks for Small Craft Marinas

    Science.gov (United States)

    Keen, A.; Eskijian, M.; Lynett, P. J.; Ayca, A.

    2015-12-01

    Because of the damage resulting from the 2010 Chile and 2011 Japanese tele-tsunamis, damage to the small craft marinas in California has become an important concern. This paper will explain the methodology and results used to simulate the demand and also the structural capacity of the floating dock system, composed of floating docks, fingers and moored vessels during tsunami events. The intent is to develop a predictive tool to understand the vulnerability of California's small craft harbors to tsunami events. To validate the methodology, the probabilistic model will be applied to Santa Cruz Harbor. Maps of maximum velocity and mean current direction from the 2011 Japan tsunami have been developed using a numerical model. Cleat and pile guide locations will be recorded and georeferenced from aerial images before the event. The fragility curves for each dock/finger system will be compared with damage reports and aerial images from just after the tsunami event. A discussion of how the fragility curves compare with the damage reports will be included. It is anticipated that these curves will be useful to marina operators to use as a tool to determine where rehabilitation might be necessary to mitigate some of the damage from the next event. Conclusions will focus on how results can be used by marina operators to reduce harbor vulnerability to tsunamis.

  15. Low material budget floating strip Micromegas for ion transmission radiography

    Energy Technology Data Exchange (ETDEWEB)

    Bortfeldt, J., E-mail: jonathan.bortfeldt@cern.ch [LMU Munich, LS Schaile, Am Coulombwall 1, D-85748 Garching (Germany); Biebel, O.; Flierl, B.; Hertenberger, R.; Klitzner, F.; Lösel, Ph. [LMU Munich, LS Schaile, Am Coulombwall 1, D-85748 Garching (Germany); Magallanes, L. [LMU Munich, LS Parodi, Am Coulombwall 1, D-85748 Garching (Germany); University Hospital Heidelberg, Im Neuenheimer Feld 672, D-69120 Heidelberg (Germany); Müller, R. [LMU Munich, LS Schaile, Am Coulombwall 1, D-85748 Garching (Germany); Parodi, K. [LMU Munich, LS Parodi, Am Coulombwall 1, D-85748 Garching (Germany); Heidelberg Ion-Beam Therapy Center, Im Neuenheimer Feld 450, D-69120 Heidelberg (Germany); Schlüter, T. [LMU Munich, Excellence Cluster Universe, Boltzmannstr. 2, D-85748 Garching (Germany); Voss, B. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstr. 1, D-64291 Darmstadt (Germany); Zibell, A. [JMU Würzburg, Sanderring 2, D-97070 Würzburg (Germany)

    2017-02-11

    Floating strip Micromegas are high-accuracy and discharge insensitive gaseous detectors, able to track single particles at fluxes of 7 MHz/cm{sup 2} with 100 μm resolution. We developed low-material-budget detectors with one-dimensional strip readout, suitable for tracking at highest particle rates as encountered in medical ion transmission radiography or inner tracker applications. Recently we additionally developed Kapton-based floating strip Micromegas with two-dimensional strip readout, featuring an overall thickness of 0.011 X{sub 0}. These detectors were tested in high-rate proton and carbon-ion beams at the tandem accelerator in Garching and the Heidelberg Ion-Beam Therapy Center, operated with an optimized Ne:CF{sub 4} gas mixture. By coupling the Micromegas detectors to a new scintillator based range detector, ion transmission radiographies of PMMA and tissue-equivalent phantoms were acquired. The range detector with 18 layers is read out via wavelength shifting fibers, coupled to a multi-anode photomultiplier. We present the performance of the Micromegas detectors with respect to timing and single plane track reconstruction using the μTPC method. We discuss the range resolution of the scintillator range telescope and present the image reconstruction capabilities of the combined system.

  16. Sphagnum growth in floating cultures: Effect of planting design

    Directory of Open Access Journals (Sweden)

    Y. Hoshi

    2017-11-01

    Full Text Available To establish rapid and stable Sphagnum growth, capitulum culture of a selected strain of S. palustre was carried out using a floating culture method. Four planting treatments were tested at mountain and urban sites in Kumamoto Prefecture on Kyushu Island, south-west Japan. Capitula were planted in colonies of different sizes on 30 cm square floating rafts, but with strict control of the number (75–77 of capitula per raft. The initial cover of live green Sphagnum ranged from 15 to 20 %. Growth of the colonies was followed throughout the growing season (April to November of 2008. After three months, green coverage rates reached 40–50 % in all planting treatments. At the end of the growing season, the highest Sphagnum cover (almost 90 % at the urban site was recorded in the planting treatment with eleven re-introduced colonies of seven capitula (‘11×7cap’, while the highest capitulum number and biomass (dry weight gain occurred in the ‘4×19cap’ planting treatment. Average stem elongation ranged from 5 cm to 7 cm in the ‘77×1cap’ and ‘4×19cap’planting treatments, respectively, indicating that the larger sized colony grew longer stems. However, contrary to expectation, the ‘4×19cap’planting treatment - which had the largest colony size - did not deliver the highest number of newly formed side shoots.

  17. JPEG2000 Compatible Lossless Coding of Floating-Point Data

    Directory of Open Access Journals (Sweden)

    Usevitch BryanE

    2007-01-01

    Full Text Available Many scientific applications require that image data be stored in floating-point format due to the large dynamic range of the data. These applications pose a problem if the data needs to be compressed since modern image compression standards, such as JPEG2000, are only defined to operate on fixed-point or integer data. This paper proposes straightforward extensions to the JPEG2000 image compression standard which allow for the efficient coding of floating-point data. These extensions maintain desirable properties of JPEG2000, such as lossless and rate distortion optimal lossy decompression from the same coded bit stream, scalable embedded bit streams, error resilience, and implementation on low-memory hardware. Although the proposed methods can be used for both lossy and lossless compression, the discussion in this paper focuses on, and the test results are limited to, the lossless case. Test results on real image data show that the proposed lossless methods have raw compression performance that is competitive with, and sometime exceeds, current state-of-the-art methods.

  18. JPEG2000 Compatible Lossless Coding of Floating-Point Data

    Directory of Open Access Journals (Sweden)

    Bryan E. Usevitch

    2007-02-01

    Full Text Available Many scientific applications require that image data be stored in floating-point format due to the large dynamic range of the data. These applications pose a problem if the data needs to be compressed since modern image compression standards, such as JPEG2000, are only defined to operate on fixed-point or integer data. This paper proposes straightforward extensions to the JPEG2000 image compression standard which allow for the efficient coding of floating-point data. These extensions maintain desirable properties of JPEG2000, such as lossless and rate distortion optimal lossy decompression from the same coded bit stream, scalable embedded bit streams, error resilience, and implementation on low-memory hardware. Although the proposed methods can be used for both lossy and lossless compression, the discussion in this paper focuses on, and the test results are limited to, the lossless case. Test results on real image data show that the proposed lossless methods have raw compression performance that is competitive with, and sometime exceeds, current state-of-the-art methods.

  19. On the mechanism of floating and sliding of liquid marbles.

    Science.gov (United States)

    Bormashenko, Edward; Bormashenko, Yelena; Musin, Albina; Barkay, Zahava

    2009-03-09

    The mechanisms of floating and sliding of liquid marbles are studied. Liquid marbles containing CaCl(2) and marbles containing NaOH water solutions float on water containing Na(2)CO(3) and an alcoholic solution of phenolphthalein with no chemical reaction. Sliding of liquid marbles, consisting of NaOH water solutions, on polymer substrates coated with phenolphthalein is studied as well. No chemical reaction is observed. These observations supply direct experimental evidence for the suggestion that interfaces are separated by an air layer when marbles roll on solid substrates. It is concluded that a liquid marble rests on hydrophobic particles coating the liquid. In contrast, drops containing an NaOH water solution sliding on superhydrophobic surfaces coated with phenolphthalein leave a colored trace. The mechanism of low-friction sliding of drops deposited on superhydrophobic surfaces and liquid marbles turns out to be quite different: there is no direct contact between liquid and solid in the case of marbles' motion.

  20. Wake Influence on Dynamic Load Characteristics of Offshore Floating Wind Turbines

    DEFF Research Database (Denmark)

    Jeon, Minu; Lee, Soogab; Kim, Taeseong

    2016-01-01

    Because the flow conditions of an offshore floating wind turbine and onshore fixed wind turbine differ, it is debatable whether the aerodynamic load predictions of an offshore floating wind turbine using the conventional blade-element momentum theory, which does not consider the dynamic wake effe...

  1. Low Noise Bias Current/Voltage References Based on Floating-Gate MOS Transistors

    DEFF Research Database (Denmark)

    Igor, Mucha

    1997-01-01

    The exploitation of floating-gate MOS transistors as reference current and voltage sources is investigated. Test structures of common source and common drain floating-gate devices have been implemented in a commercially available 0.8 micron double-poly CMOS process. The measurements performed...

  2. 14 CFR 25.529 - Hull and main float landing conditions.

    Science.gov (United States)

    2010-01-01

    ... float landing conditions. (a) Symmetrical step, bow, and stern landing. For symmetrical step, bow, and stern landings, the limit water reaction load factors are those computed under § 25.527. In addition— (1.... (b) Unsymmetrical landing for hull and single float seaplanes. Unsymmetrical step, bow, and stern...

  3. Floating mats: their occurrence and influence on shoreline distribution of emergent vegetation

    NARCIS (Netherlands)

    Azza, N.; Denny, P.; Van de Koppel, J.; Kansiime, F.

    2006-01-01

    1. A study was conducted on the northern shore of Lake Victoria (Uganda) to determine the factors controlling the occurrence of floating root mats and the influence of the floating mats on the distribution of emergent vegetation. 2. Environmental conditions within 78 bays in the study area were

  4. Kazuo Ishiguros romaner i helteperspektiv, specielt An Artist of the Floating World

    DEFF Research Database (Denmark)

    Klitgård, Ebbe

    2006-01-01

    På baggrund af en forfatterskabskarakteristik behandles Kazuo Ishiguros romaner i helteperspektiv og i forlængelse heraf foretages en romananalyse af An Artist of the Floating World fra 1986.......På baggrund af en forfatterskabskarakteristik behandles Kazuo Ishiguros romaner i helteperspektiv og i forlængelse heraf foretages en romananalyse af An Artist of the Floating World fra 1986....

  5. A Descriptive Study of Pre-Service Science Teachers' Misconceptions about Sinking-Floating

    Science.gov (United States)

    Kiray, Seyit Ahmet; Aktan, Filiz; Kaynar, Hamza; Kilinc, Sena; Gorkemli, Tugce

    2015-01-01

    The purpose of this study is twofold. Firstly, it attempts to determine the pre-service science teachers' misconceptions about floating and sinking. Secondly, it aims to reveal the level of pre-service science teachers' misconceptions, scientific knowledge, lack of knowledge, and lack of confidence related to floating and sinking. To conduct the…

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Conceptual Design of a Floating Support Structure and Mooring System for a Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Berthelsen, Petter Andreas; Fylling, Ivar; Vita, Luca

    2012-01-01

    This paper deals with the conceptual design of a floating support structure and mooring system for a 5MW vertical axis offshore wind turbine. The work is carried out as part of the DeepWind project, where the main objective is to investigate the feasibility of a floating vertical axis offshore wind...

  8. Integrated simulation challenges with the DeepWind floating vertical axis wind turbine concept

    DEFF Research Database (Denmark)

    Verelst, David; Aagaard Madsen, Helge; Borg, Michael

    2015-01-01

    This paper presents the experiences and challenges with concurrently carrying out numerical model development, integrated simulations and design of a novel floating vertical axis wind turbine, the DeepWind concept. The floating VAWT modelling capabilities of the aero-hydro-elastic HAWC2 simulation...

  9. Wake losses optimization of offshore wind farms with moveable floating wind turbines

    NARCIS (Netherlands)

    S.F. Rodrigues; R. Teixeira Pinto (Rodrigo); M. Soleimanzadeh (Maryam); P.A.N. Bosman (Peter); P. Bauer (Pavol)

    2015-01-01

    htmlabstractIn the future, floating wind turbines could be used to harvest energy in deep offshore areas where higher wind mean speeds are observed. Currently, several floating turbine concepts are being designed and tested in small scale projects; in particular, one concept allows the turbine to

  10. Hydroelastic analysis of a very large floating plate with large deflections in stochastic seaway

    DEFF Research Database (Denmark)

    Chen, Xu-jun; Jensen, Jørgen Juncher; Cui, Wei-cheng

    2004-01-01

    The hydroelasticity of a very large floating plate with large deflections in multidirectional irregular waves is discussed. After a brief introduction on wave loads on a flexible structure, the paper derives the generalised fluid force acting on a floating structure in multidirectional irregular ...

  11. Development and Characterization of Novel Floating-Mucoadhesive Tablets Bearing Venlafaxine Hydrochloride

    Directory of Open Access Journals (Sweden)

    Raghvendra Misra

    2016-01-01

    Full Text Available The present investigation is concerned about the development of floating bioadhesive drug delivery system of venlafaxine hydrochloride which after oral administration exhibits a unique combination of floating and bioadhesion to prolong gastric residence time and increase drug bioavailability within the stomach. The floating bioadhesive tablets were prepared by the wet granulation method using different ratios of hydroxypropyl methyl cellulose (HPMC K4MCR and Carbopol 934PNF as polymers. Sodium bicarbonate (NaHCO3 and citric acid were used as gas (CO2 generating agents. Tablets were characterized for floating properties, in vitro drug release, detachment force, and swelling index. The concentration of hydroxypropyl methyl cellulose and Carbopol 934PNF significantly affects the in vitro drug release, floating properties, detachment force, and swelling properties of the tablets. The optimized formulation showed the floating lag time 72±2.49 seconds and duration of floating 24.50±0.74 hr. The in vitro release studies and floating behavior were studied in simulated gastric fluid (SGF at pH 1.2. Different drug release kinetics models were also applied. The in vitro drug release from tablets was sufficiently sustained (more than 18 hr and the Fickian transports of the drug from the tablets were confirmed. The radiological evidence suggests that the tablets remained buoyant and altered position in the stomach of albino rabbit and mean gastric residence time was prolonged (more than > 6 hr.

  12. Resistance and resilience of floating mat fens in interior Alaska following airboat disturbance

    Science.gov (United States)

    Amy Zacheis; Kate Doran

    2009-01-01

    The floating mat fens of the Tanana Flats in interior Alaska are productive wetlands near the urban center of Fairbanks. Airboat traffic has created a network of trails through the floating vegetation mats. We established protected areas along established trails, which allowed for measurement of plant community resistance to airboat traffic and resilience following...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Are the older ARGO-Floats more vulnerable to Fouling and Associated Salinity drift compared to that of later deployments?

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Youn, Y.H.; Lee, H.

    Continued existence of ARGO floats for years together (4 year) make the conductivity cell more vulnerable to fouling and associated drift in salinity measurements In this paper, the authors address this issue by making use of floats deployed...

  15. New levodopa sustained-release floating minitablets coated with insoluble acrylic polymer.

    Science.gov (United States)

    Goole, J; Deleuze, Ph; Vanderbist, F; Amighi, K

    2008-02-01

    The aim of this study was to develop a new coated multiple-unit sustained-release floating system that is able to float over an extended period of time. Levodopa was used as a model drug. The system consisted of a 3mm drug-containing gas-generating core, prepared by melt granulation and subsequent compression, and coated with a flexible polymeric membrane. Eudragit RL30D and ATEC were used as a film former and a plasticizer, respectively. The coating level was fixed at 20% (w/w). The floating lag time decreased as the proportion of effervescent agents increased. The optimized coated floating minitablets could float within 20min and remained buoyant for more than 13h. In addition, a sustained release of levodopa for more than 20h was observed.

  16. Current-Sensitive Path Planning for an Underactuated Free-Floating Ocean Sensorweb

    Science.gov (United States)

    Dahl, Kristen P.; Thompson, David R.; McLaren, David; Chao, Yi; Chien, Steve

    2011-01-01

    This work investigates multi-agent path planning in strong, dynamic currents using thousands of highly under-actuated vehicles. We address the specific task of path planning for a global network of ocean-observing floats. These submersibles are typified by the Argo global network consisting of over 3000 sensor platforms. They can control their buoyancy to float at depth for data collection or rise to the surface for satellite communications. Currently, floats drift at a constant depth regardless of the local currents. However, accurate current forecasts have become available which present the possibility of intentionally controlling floats' motion by dynamically commanding them to linger at different depths. This project explores the use of these current predictions to direct float networks to some desired final formation or position. It presents multiple algorithms for such path optimization and demonstrates their advantage over the standard approach of constant-depth drifting.

  17. The Application Modular Floating Pontoon to Support Floods Disaster Evacuation System in Heavy Populated Residential Area

    Directory of Open Access Journals (Sweden)

    Ahmad Fauzan Zakki

    2014-10-01

    Full Text Available During floods disaster in the heavy populated residential area, the lack of existing life saving appliances system such as rubber boat and wooden boat were not able to evacuate the disaster victims spontaneously in mass. The condition might be explained since the rubber boat and wooden boat have limited occupant capacity. Based on the conditions, the main objectives of the research are focused on the evaluation of the application of modular floating pontoon as multipurpose floating equipment to support floods disaster evacuation process. The investigation of the modular floating pontoon performance such as hydrostatics characteristics, the equilibrium condition and the intact stability was studied using strip theory and Krylov’s method. Furthermore, the strength analysis of the modular floating pontoon structure was calculated using finite element method. The results show that the modular floating pontoon is reliable to support the evacuation process.

  18. Frequency-domain characteristics of aerodynamic loads of offshore floating vertical axis wind turbines

    DEFF Research Database (Denmark)

    Borg, Michael; Collu, M.

    2015-01-01

    The re-emerging interest in vertical axis wind turbines for floating offshore applications has led to a need to investigate the relatively complex dynamics of such floating offshore structures. Through the use of a coupled model of dynamics this article investigates the frequency-domain character......The re-emerging interest in vertical axis wind turbines for floating offshore applications has led to a need to investigate the relatively complex dynamics of such floating offshore structures. Through the use of a coupled model of dynamics this article investigates the frequency......-domain characteristics of floating vertical axis wind turbine aerodynamic loads. The impact of platform induced motion on aerodynamic loads is discussed in detail, with results indicating an increase in aerodynamic loads of several orders of magnitude over the range of frequencies usually containing significant wave...

  19. Floating microspheres of valacyclovir HCl: Formulation, optimization, characterization, in vitro and in vivo floatability studies

    Directory of Open Access Journals (Sweden)

    Nilamgiri Goswami

    2012-01-01

    Full Text Available Floating microspheres are multiple unit Gastroretentive drug delivery systems. Valacyclovir hydrochloride (VCH is L-valyl ester prodrug of acyclovir. VCH degrades in intestinal fluid. The objective was to develop floating microspheres of VCH to localise the drug at upper part of GIT, for improved absorption. Floating microspheres were prepared by W/O emulsification solvent evaporation method using Ethylcellulose (EC as polymer. Particle size and % EE were 550.021±0.241 μm, 79.88±2.236% respectively. in vitro and in vivo floatability studies confirmed floating behaviour of microspheres. VCH loaded floating microspheres can be a suitable alternative to the conventional formulation, by localizing the drug at upper GIT.

  20. Development of the Floating Centrifugal Pump by Use of Non Contact Magnetic Drive and Its Performance

    Directory of Open Access Journals (Sweden)

    Mitsuo Uno

    2004-01-01

    Full Text Available This article focuses on the impeller construction, non contact driving method and performance of a newly developed shaftless floating pump with centrifugal impeller. The drive principle of the floating impeller pump used the magnet induction method similar to the levitation theory of the linear motor. In order to reduce the axial thrust by the pressure different between shroud and disk side, the balance hole and the aileron blade were installed in the floating impeller. Considering the above effect, floating of an impeller in a pump was realized. Moreover, the performance curves of a developed pump are in agreement with a general centrifugal pump, and the dimensionless characteristic curve also agrees under the different rotational speed due to no mechanical friction of the rotational part. Therefore, utility of a non contacting magnetic-drive style pump with the floating impeller was made clear.

  1. Drift in salinity data from Argo profiling floats in the Sea of Japan

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Bajish, C.C; Behera, S.; Gopalakrishna, V.V.

    . The efficiency of this new method in finding out possible drift in the Argo salinity is demonstrated in the Sea of Japan (SOJ) by using the "near-linear" subsurface salinity structure of the SOJ. The new method is based on the time–space decorrelation scale...

  2. Characterization of airborne float coal dust emitted during continuous mining, longwall mining and belt transport.

    Science.gov (United States)

    Shahan, M R; Seaman, C E; Beck, T W; Colinet, J F; Mischler, S E

    2017-09-01

    Float coal dust is produced by various mining methods, carried by ventilating air and deposited on the floor, roof and ribs of mine airways. If deposited, float dust is re-entrained during a methane explosion. Without sufficient inert rock dust quantities, this float coal dust can propagate an explosion throughout mining entries. Consequently, controlling float coal dust is of critical interest to mining operations. Rock dusting, which is the adding of inert material to airway surfaces, is the main control technique currently used by the coal mining industry to reduce the float coal dust explosion hazard. To assist the industry in reducing this hazard, the Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health initiated a project to investigate methods and technologies to reduce float coal dust in underground coal mines through prevention, capture and suppression prior to deposition. Field characterization studies were performed to determine quantitatively the sources, types and amounts of dust produced during various coal mining processes. The operations chosen for study were a continuous miner section, a longwall section and a coal-handling facility. For each of these operations, the primary dust sources were confirmed to be the continuous mining machine, longwall shearer and conveyor belt transfer points, respectively. Respirable and total airborne float dust samples were collected and analyzed for each operation, and the ratio of total airborne float coal dust to respirable dust was calculated. During the continuous mining process, the ratio of total airborne float coal dust to respirable dust ranged from 10.3 to 13.8. The ratios measured on the longwall face were between 18.5 and 21.5. The total airborne float coal dust to respirable dust ratio observed during belt transport ranged between 7.5 and 21.8.

  3. Leaky Integrate-and-Fire Neuron Circuit Based on Floating-Gate Integrator.

    Science.gov (United States)

    Kornijcuk, Vladimir; Lim, Hyungkwang; Seok, Jun Yeong; Kim, Guhyun; Kim, Seong Keun; Kim, Inho; Choi, Byung Joon; Jeong, Doo Seok

    2016-01-01

    The artificial spiking neural network (SNN) is promising and has been brought to the notice of the theoretical neuroscience and neuromorphic engineering research communities. In this light, we propose a new type of artificial spiking neuron based on leaky integrate-and-fire (LIF) behavior. A distinctive feature of the proposed FG-LIF neuron is the use of a floating-gate (FG) integrator rather than a capacitor-based one. The relaxation time of the charge on the FG relies mainly on the tunnel barrier profile, e.g., barrier height and thickness (rather than the area). This opens up the possibility of large-scale integration of neurons. The circuit simulation results offered biologically plausible spiking activity (field-effect transistor. The FG-LIF neuron also has the advantage of low operation power (<30 pW/spike). Finally, the proposed circuit was subject to possible types of noise, e.g., thermal noise and burst noise. The simulation results indicated remarkable distributional features of interspike intervals that are fitted to Gamma distribution functions, similar to biological neurons in the neocortex.

  4. Verification of New Floating Capabilities in FAST v8: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, F.; Robertson, A.; Jonkman, J.; Hayman, G.

    2015-01-01

    In the latest release of NREL's wind turbine aero-hydro-servo-elastic simulation software, FAST v8, several new capabilities and major changes were introduced. FAST has been significantly altered to improve the simulator's modularity and to include new functionalities in the form of modules in the FAST v8 framework. This paper is focused on the improvements made for the modeling of floating offshore wind systems. The most significant change was to the hydrodynamic load calculation algorithms, which are embedded in the HydroDyn module. HydroDyn is now capable of applying strip-theory (via an extension of Morison's equation) at the member level for user-defined geometries. Users may now use a strip-theory-only approach for applying the hydrodynamic loads, as well as the previous potential-flow (radiation/diffraction) approach and a hybrid combination of both methods (radiation/diffraction and the drag component of Morison's equation). Second-order hydrodynamic implementations in both the wave kinematics used by the strip-theory solution and the wave-excitation loads in the potential-flow solution were also added to HydroDyn. The new floating capabilities were verified through a direct code-to-code comparison. We conducted a series of simulations of the International Energy Agency Wind Task 30 Offshore Code Comparison Collaboration Continuation (OC4) floating semisubmersible model and compared the wind turbine response predicted by FAST v8, the corresponding FAST v7 results, and results from other participants in the OC4 project. We found good agreement between FAST v7 and FAST v8 when using the linear radiation/diffraction modeling approach. The strip-theory-based approach inherently differs from the radiation/diffraction approach used in FAST v7 and we identified and characterized the differences. Enabling the second-order effects significantly improved the agreement between FAST v8 and the other OC4 participants.

  5. On the relative importance of loads acting on a floating verticalaxis wind turbine system when evaluating the global system response

    DEFF Research Database (Denmark)

    Collu, Maurizio; Borg, Michael; Manuel, Lance

    2016-01-01

    Interest in offshore floating wind turbines has been growing over the last decade. While a number of studies have been conducted to model the dynamics of offshore floating HAWT systems (e.g. OC3-Phase IV, OC4-Phase II), relatively few studies have been conducted on floating VAWT systems, despite ...

  6. Hydrodynamic analysis of a floating body with an open chamber using a 2D fully nonlinear numerical wave tank

    Directory of Open Access Journals (Sweden)

    Ahmed Syed Uzair

    2012-09-01

    Full Text Available Hydrodynamic analysis of a surface-piercing body with an open chamber was performed with incident regular waves and forced-heaving body motions. The floating body was simulated in the time domain using a 2D fully nonlinear numerical wave tank (NWT technique based on potential theory. This paper focuses on the hydrodynamic behavior of the free surfaces inside the chamber for various input conditions, including a two-input system: both incident wave profiles and forced body velocities were implemented in order to calculate the maximum surface elevations for the respective inputs and evaluate their interactions. An appropriate equivalent linear or quadratic viscous damping coefficient, which was selected from experimental data, was employed on the free surface boundary inside the chamber to account for the viscous energy loss on the system. Then a comprehensive parametric study was performed to investigate the nonlinear behavior of the wave-body interaction.

  7. Damping Wind and Wave Loads on a Floating Wind Turbine

    DEFF Research Database (Denmark)

    Christiansen, Søren; Bak, Thomas; Knudsen, Torben

    2013-01-01

    Offshore wind energy capitalizes on the higher and less turbulent wind speeds at sea. To enable deployment of wind turbines in deep-water locations, structures are being explored, where wind turbines are placed on a floating platform. This combined structure presents a new control problem, due...... to the partly unconstrained movement of the platform and ocean wave excitation. If this additional complexity is not dealt with properly, this may lead to a significant increase in the structural loads and, potentially, instability of the controlled system. In this paper, the wave excitation is investigated......, and we show the influence that both wind speed, wave frequencies and misalignment between wind and waves have on the system dynamics. A new control model is derived that extends standard turbine models to include the hydrodynamics, additional platform degrees of freedom, the platform mooring system...

  8. Mooring line damping estimation for a floating wind turbine.

    Science.gov (United States)

    Qiao, Dongsheng; Ou, Jinping

    2014-01-01

    The dynamic responses of mooring line serve important functions in the station keeping of a floating wind turbine (FWT). Mooring line damping significantly influences the global motions of a FWT. This study investigates the estimation of mooring line damping on the basis of the National Renewable Energy Laboratory 5 MW offshore wind turbine model that is mounted on the ITI Energy barge. A numerical estimation method is derived from the energy absorption of a mooring line resulting from FWT motion. The method is validated by performing a 1/80 scale model test. Different parameter changes are analyzed for mooring line damping induced by horizontal and vertical motions. These parameters include excitation amplitude, excitation period, and drag coefficient. Results suggest that mooring line damping must be carefully considered in the FWT design.

  9. A Floating Offshore Wind Turbine in Extreme Wave Conditions

    DEFF Research Database (Denmark)

    Wehmeyer, Christof

    and purposes oriented design procedures are the backbone of a cost efficient offshore wind industry. Conventional engineering procedures for the assessment of extreme event impacts, i.e. ultimate limit state (ULS) analysis of floating structures, as they have been used in the oil and gas industry, neglect two...... not be sufficient to describe realistic wave shapes and the respective loads, especially in ULS conditions. In shallow or intermediate water depth environments, i.e. when the ratio between the water depth and the wave length becomes smaller than 0.5, waves need to be described by non-linear approaches, in order...... and water depths are considered, where wave shapes in the extreme sea states deviate from the 1st order description. A design basis is developed, which defines parametric extreme sea state caused by measured cyclonic storm conditions. The sea state parameters are defined, such that their reoccurrence...

  10. A Numerical Model for a Floating TLP Wind Turbine

    DEFF Research Database (Denmark)

    Kumari Ramachandran, Gireesh Kumar Vasanta

    A numerical model is developed for a TLP configuration of a floating offshore wind turbine. The platform dynamics and hydrodynamic forces are derived and implemented in an advanced aero-elastic code, Flex5, to compute the hydro-aero-servo-elastic loads and responses on the floater and the wind...... turbine. This is achieved through three steps. In the first step, an independent 2D code with fourteen degrees of freedom (DOFs) is developed and the responses are verified for load cases concerning steady and spatially coherent turbulent wind with regular and irregular waves. In the second step, the 2D...... irregular waves. In addition, the effect of wind-wave misalignment is investigated. Further, in the third step, the 3D platform dynamics and wave loading are implemented into Flex5, resulting in a fully coupled hydro-aero-servo-elastic code. The implementation is tested to make the model reliable and robust...

  11. Photo-active float for field water disinfection.

    Science.gov (United States)

    Shwetharani, R; Balakrishna, R Geetha

    2016-03-01

    The present study investigates the antibacterial activity of a photoactive float fabricated with visible light active N-F-TiO2 for the disinfection of field water widely contaminated with Gram positive and Gram negative bacteria like, Salmonella typhimurium (Gram negative), Escherichia coli (Gram negative), Staphylococcus aureus (Gram positive), Bacillus species (Gram positive), and Pseudomonas species (Gram negative). The antibacterial activity can be attributed to the unique properties of the photocatalyst, which releases reactive oxygen species in aqueous solution, under the illumination of sunlight. N-F-TiO2 nanoparticles efficiently photocatalyse the destruction of all the bacteria present in the contaminated water, giving clean water. The inactivation of bacteria is confirmed by a standard plate count method, MDA, RNA and DNA analysis. The purity of water was further validated by SPC indicating nil counts of bacteria after two days of storing and testing. The photocatalysts were characterized by XRD, BET measurement, SEM, EDX, UV-Vis and PL analysis.

  12. A Floating Offshore Wind Turbine in Extreme Wave Conditions

    DEFF Research Database (Denmark)

    Wehmeyer, Christof

    for further optimization and the consequent potential to make FOWT cost competitive. Generally the study shows that the hybrid modelling approach might currently be sufficient for pre-Detailed Design stages, where higher degrees of conservatism are acceptable. However for multi-unit production the current......While the design of floating offshore wind turbines (FOWT) is still at an infant stage, the general desire to realise them is strong. According to a poll conducted by GL Garrad Hassan at the HUSUM 2012 Wind Energy Trade Fair, 62% of the attendees believed that floaters will be a part of the mix...... and will even overtake bottom fixed foundation within the coming two decades, Bossler (2011). FOWTs are believed having a large potential of lowering the cost of energy (CoE). The CoE minimization is currently the main driver for technological development in the offshore wind industry. Therefore reliable...

  13. Wave energy absorption by a floating air bag

    DEFF Research Database (Denmark)

    Kurniawan, Adi; Chaplin, John; Greaves, Deborah

    2017-01-01

    properties, which are successfully predicted numerically. Owing to its compressibility, the device can have a heave resonance period longer than that of a rigid device of the same shape and size, without any phase control. Furthermore, varying the amount of air in the bag is found to change its shape......A floating air bag, ballasted in water, expands and contracts as it heaves under wave action. Connecting the bag to a secondary volume via a turbine transforms the bag into a device capable of generating useful energy from the waves. Small-scale measurements of the device reveal some interesting...... and hence its dynamic response, while varying the turbine damping or the air volume ratio changes the dynamic response without changing the shape....

  14. Mooring Line Damping Estimation for a Floating Wind Turbine

    Directory of Open Access Journals (Sweden)

    Dongsheng Qiao

    2014-01-01

    Full Text Available The dynamic responses of mooring line serve important functions in the station keeping of a floating wind turbine (FWT. Mooring line damping significantly influences the global motions of a FWT. This study investigates the estimation of mooring line damping on the basis of the National Renewable Energy Laboratory 5 MW offshore wind turbine model that is mounted on the ITI Energy barge. A numerical estimation method is derived from the energy absorption of a mooring line resulting from FWT motion. The method is validated by performing a 1/80 scale model test. Different parameter changes are analyzed for mooring line damping induced by horizontal and vertical motions. These parameters include excitation amplitude, excitation period, and drag coefficient. Results suggest that mooring line damping must be carefully considered in the FWT design.

  15. Wave-induced collisions of thin floating disks

    Science.gov (United States)

    Yiew, L. J.; Bennetts, L. G.; Meylan, M. H.; Thomas, G. A.; French, B. J.

    2017-12-01

    Collisions between two thin floating disks forced by regular water waves are studied for a range of wave amplitudes and lengths, using laboratory wave basin experiments and a mathematical model. Three collision regimes are identified from the experiments in terms of collision frequency and strength, and the collisions are shown to be caused by drift for short incident wavelengths and relative surge motion between the disks for longer incident waves. The model is based on slope-sliding theory for the wave-induced disk motions and rigid-body collisions. It is shown to predict collision frequencies and velocities accurately for intermediate-long incident wavelengths. Incorporating drift and wave scattering forces into the model is shown to capture the collision behaviours for short incident wavelengths.

  16. Unique ecological impacts associated with offshore floating nuclear power plants

    International Nuclear Information System (INIS)

    Adams, S.M.; McLean, R.B.

    1979-01-01

    The ecological impacts that could occur as a result of site construction and operation of an offshore floating nuclear power plant are identified by comparing the principal ecological features associated with offshore siting with those associated with the siting of onshore estuarine plants. In general, the ecological impacts of offshore nuclear plants should be relatively smaller than those of estuarine plants. Possible factors that could increase the relative impacts of offshore plants are high frequency of contact with schools of fish, siting near inlets to estuaries or other ecologically important areas, and the persistence of halogen residuals. Identifying the potential ecological impacts associated with the siting of offshore plants permits the development of various monitoring programs and measures to minimize these impacts

  17. Optimized Latching Control of Floating Point Absorber Wave Energy Converter

    Science.gov (United States)

    Gadodia, Chaitanya; Shandilya, Shubham; Bansal, Hari Om

    2018-03-01

    There is an increasing demand for energy in today’s world. Currently main energy resources are fossil fuels, which will eventually drain out, also the emissions produced from them contribute to global warming. For a sustainable future, these fossil fuels should be replaced with renewable and green energy sources. Sea waves are a gigantic and undiscovered vitality asset. The potential for extricating energy from waves is extensive. To trap this energy, wave energy converters (WEC) are needed. There is a need for increasing the energy output and decreasing the cost requirement of these existing WECs. This paper presents a method which uses prediction as a part of the control scheme to increase the energy efficiency of the floating-point absorber WECs. Kalman Filter is used for estimation, coupled with latching control in regular as well as irregular sea waves. Modelling and Simulation results for the same are also included.

  18. Wave energy, lever operated pivoting float LOPF study

    Energy Technology Data Exchange (ETDEWEB)

    Margheritini, L.

    2012-11-01

    The fully instrumented Resen Waves Lever Operated Pivoting Float LOPF wave energy buoy model has gone through the first stage of testing in regular waves in scale 1:25 of the North Sea wave conditions, in the 3D deep wave basin at the Hydraulic and Coastal Engineering Laboratory of Aalborg University in Denmark. The model size was 60cm W x 90cm L x 21cm H. The 60 cm width pointed towards the wave front. The LOPF buoy is characterized by a simple mechanical design with few moving parts and direct electrical output and it is taut moored to the sea bed, so all forces are referenced to the seabed for maximum energy output in regular as well as irregular waves. During storms the buoy pivots and streamlines itself to minimize loads on the mooring line. A conservative estimate shows that a full scale system for North Sea conditions has a float size width of 15 m that will, with 60% generator efficiency, produce 610 MWh/y (609.497 kWh/y) with an average power output of 69.6 kW, which requires a generator capacity of 700 kW. It is expected the generator efficiency can be increased to 90% in the future. More specific calculations (from EnergiNet) show that with one generator of 695 kW the expected power production is 585 MWh/y; with a generator of 250 kW and 100 kW, the expected power production is 481 MWh/y and 182 MWh/y respectively. In addition there are several areas for future improvements for increased power production. (Author)

  19. Castaways can't be choosers - Homogenization of rafting assemblages on floating seaweeds

    Science.gov (United States)

    Gutow, Lars; Beermann, Jan; Buschbaum, Christian; Rivadeneira, Marcelo M.; Thiel, Martin

    2015-01-01

    After detachment from benthic habitats, the epibiont assemblages on floating seaweeds undergo substantial changes, but little is known regarding whether succession varies among different seaweed species. Given that floating algae may represent a limiting habitat in many regions, rafting organisms may be unselective and colonize any available seaweed patch at the sea surface. This process may homogenize rafting assemblages on different seaweed species, which our study examined by comparing the assemblages on benthic and floating individuals of the fucoid seaweeds Fucus vesiculosus and Sargassum muticum in the northern Wadden Sea (North Sea). Species richness was about twice as high on S. muticum as on F. vesiculosus, both on benthic and floating individuals. In both seaweed species benthic samples were more diverse than floating samples. However, the species composition differed significantly only between benthic thalli, but not between floating thalli of the two seaweed species. Separate analyses of sessile and mobile epibionts showed that the homogenization of rafting assemblages was mainly caused by mobile species. Among these, grazing isopods from the genus Idotea reached extraordinarily high densities on the floating samples from the northern Wadden Sea, suggesting that the availability of seaweed rafts was indeed limiting. Enhanced break-up of algal rafts associated with intense feeding by abundant herbivores might force rafters to recolonize benthic habitats. These colonization processes may enhance successful dispersal of rafting organisms and thereby contribute to population connectivity between sink populations in the Wadden Sea and source populations from up-current regions.

  20. Impact of associated injuries in the Floating knee: A retrospective study

    Science.gov (United States)

    Rethnam, Ulfin; Yesupalan, Rajam S; Nair, Rajagopalan

    2009-01-01

    Background Floating knee injuries are usually associated with other significant injuries. Do these injuries have implications on the management of the floating knee and the final outcome of patients? Our study aims to assess the implications of associated injuries in the management and final outcome of floating knee. Methods 29 patients with floating knees were assessed in our institution. A retrospective analysis of medical records and radiographs were done and all associated injuries were identified. The impact of associated injuries on delay in initial surgical management, delay in rehabilitation & final outcome of the floating knee were assessed. Results 38 associated injuries were noted. 7 were associated with ipsilateral knee injuries. Lower limb injuries were most commonly associated with the floating knee. Patients with some associated injuries had a delay in surgical management and others a delay in post-operative rehabilitation. Knee ligament and vascular injuries were associated with poor outcome. Conclusion The associated injuries were quite frequent with the floating knee. Some of the associated injuries caused a delay in surgical management and post-operative rehabilitation. In assessment of the final outcome, patients with associated knee and vascular injuries had a poor prognosis. Majority of the patients with associated injuries had a good or excellent outcome. PMID:19144197

  1. Effect of stearic acid on the properties of metronidazole/methocel K4M floating matrices

    Directory of Open Access Journals (Sweden)

    Belem Lara-Hernández

    2009-09-01

    Full Text Available The properties of metronidazole/Methocel K4M sustained release floating tablets have been studied varying the proportion of the lubricant, stearic acid, on formulations with and without sodium bicarbonate. The variables studied include technological properties of the tablets such as tablet hardness and ejection pressure, the drug release profile, the hydration kinetics and the floating behaviour. The presence of stearic acid and sodium bicarbonate improves the floating behaviour for more than 8 hours. The hydration volume, the tablet hardness and the ejection pressure decrease as the stearic acid content increases and the polymer content decreases. Drug dissolution increases with increasing proportions of stearic acid and decreasing proportions of the polymer in the tablets. The presence of sodium bicarbonate extends the differences in dissolution produced by stearic acid. These results are attributed to decreasing matrices coherence with an increasing quantity of stearic acid and a reducing polymer proportion. The carbon dioxide bubbles produced by sodium bicarbonate expand the matrices facilitating the dissolution, although their presence obstructs also the diffusion path through the hydrated gel layer.Estudaram-se as propriedades de comprimidos flutuantes de metronidazol/Methocel K4M de liberação controlada, variando-se a proporção do lubrificante, ácido esteárico, nas formulações com e sem bicarbonato de sódio. As variáveis estudadas incluem propriedades tecnológicas dos comprimidos, tais como dureza, pressão de ejeção, perfil de liberação do fármaco, cinética de hidratação e comportamento de flutuação. A presença de ácido esteárico e do bicarbonato de sódio melhora o comportamento de flutuação para mais de 8 horas. O volume de hidratação, a dureza e a pressão de ejeção do comprimido decrescem à medida que o conteúdo de ácido esteárico e de polímero diminui. A dissolução do fármaco aumenta com o

  2. Equipment for decontamination of inner vessel surfaces featuring sound or ultrasound transducer on float inside liquid-filled vessel

    International Nuclear Information System (INIS)

    Bar, J.; Straka, M.

    1982-01-01

    The equipment for the decontamination of the inner surfaces of vessels consists of an immersion float which is provided with a screw, an electric motor, a rudder and at least one float chamber, and a remotely controlled valve. The float is provided with a power source, a high frequency a.c. current generator and a control panel outside the vessel. The float is connected to parts of the equipment outside the vessel by a multi-core cable. The immersion float may also be provided with a detector for measuring the quantity of ionizing radiation whose display is placed outside the vessel being decontaminated. (B.S.)

  3. Differential Response of Floating and Submerged Leaves of Longleaf Pondweed to Silver Ions

    Directory of Open Access Journals (Sweden)

    Nisha Shabnam

    2017-06-01

    Full Text Available In this study, we have investigated variations in the potential of floating and submerged leaves of longleaf pondweed (Potamogeton nodosus to withstand silver ion (Ag+-toxicity. Both floating and submerged leaves changed clear colorless AgNO3 solutions to colloidal brown in the presence of light. Transmission electron microscopy revealed the presence of distinct crystalline Ag-nanoparticles (Ag-NPs in these brown solutions. Powder X-ray diffraction pattern showed that Ag-NPs were composed of Ag0 and Ag2O. Photosystem (PS II efficiency of leaves declined upon exposure to Ag+ with a significantly higher decline in the submerged leaves than in the floating leaves. Similarly, Ag+ treatment caused a significant reduction in the carboxylase activity of the ribulose bisphosphate carboxylase/oxygenase in leaves. The reduction in this carboxylase activity was significantly higher in the submerged than in the floating leaves. Ag+ treatment also resulted in a significant decline in the levels of non-enzymatic and enzymatic antioxidants; the decline was significantly lower in the floating than in submerged leaves. X-ray photoelectron spectroscopy revealed the presence of Ag2O in these leaves. Inductively coupled plasma mass spectrometry analysis revealed a three-fold higher Ag content in the submerged than in floating leaves. Our study demonstrates that floating leaves of longleaf pondweed have a superior potential to counter Ag+-toxicity compared with submerged leaves, which could be due to superior potential of floating leaves to reduce Ag+ to less/non-toxic Ag0/Ag2O-nanoparticles/nanocomplexes. We suggest that modulating the genotype of longleaf pondweed to bear higher proportion of floating leaves would help in cleaning fresh water bodies contaminated with ionic forms of heavy metals.

  4. Towards Interactive Steering of a Very Large Floating Structure Code by Using HPC Parallelisation Strategies

    KAUST Repository

    Frisch, Jerome

    2012-09-01

    Very large floating structures (VLFSs) have been used for broad applications such as floating storage facilities, floating piers, floating bridges, floating airports, entertainment facilities, even habitation, and other purposes. Owing to its small bending rigidity, VLFS deforms elastically when subjected to wave action. This elastic deformation due to wave is called hydro elastic response and it can be obtained by solving the interaction between the surface wave and the floating structure in the frequency domain. In solving the fluid-structure interaction, the floating structure can be modelled by applying the finite element method, whereas the fluid part may be analyzed by using the Green\\'s function method. When using the Green\\'s function which satisfies the boundary condition on the free-surface, the sea bottom and that at infinite distance from the floating structure, the unknown parameters to be determined for the fluid part can be minimized to be only those associated with the wetted surface of the floating structure. However, in the evaluation of the Green\\'s function, extensive computation time O(N2) is needed (N is the number of unknowns). Therefore, acceleration techniques are necessary to tackle the computational complexity. Nowadays, standard multi-core office PCs are already quite powerful if all the cores can be used efficiently. This paper will show different parallelisation strategies for speeding up the Green\\'s function computation. A shared memory based implementation as well as a distributed memory concept will be analysed regarding speed-up and efficiency. For large computations, batch jobs can be used to compute detailed results in high resolution on a large computational cluster or supercomputer. Different speed-up computations on clusters will be included for showing strong speed-up results. © 2012 IEEE.

  5. Modelling of bio-optical parameters of open ocean waters

    Directory of Open Access Journals (Sweden)

    Vadim N. Pelevin

    2001-12-01

    Full Text Available An original method for estimating the concentration of chlorophyll pigments, absorption of yellow substance and absorption of suspended matter without pigments and yellow substance in detritus using spectral diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance data has been applied to sea waters of different types in the open ocean (case 1. Using the effective numerical single parameter classification with the water type optical index m as a parameter over the whole range of the open ocean waters, the calculations have been carried out and the light absorption spectra of sea waters tabulated. These spectra are used to optimize the absorption models and thus to estimate the concentrations of the main admixtures in sea water. The value of m can be determined from direct measurements of the downward irradiance attenuation coefficient at 500 nm or calculated from remote sensing data using the regressions given in the article. The sea water composition can then be readily estimated from the tables given for any open ocean area if that one parameter m characterizing the basin is known.

  6. Apparatus and method for implementing power saving techniques when processing floating point values

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Moon; Park, Sang Phill

    2017-10-03

    An apparatus and method are described for reducing power when reading and writing graphics data. For example, one embodiment of an apparatus comprises: a graphics processor unit (GPU) to process graphics data including floating point data; a set of registers, at least one of the registers of the set partitioned to store the floating point data; and encode/decode logic to reduce a number of binary 1 values being read from the at least one register by causing a specified set of bit positions within the floating point data to be read out as 0s rather than 1s.

  7. The method of rapid design of the folding bridge based on floating supports

    Directory of Open Access Journals (Sweden)

    Jan Marszałek

    2016-09-01

    Full Text Available The article includes a methodology for the rapid design of the folding bridge based on floating supports. This methodology includes an analysis of the possibilities of using blocks from the park pontoon PP-64 as a support for the floating folding DMS-65 bridge, built as a tem-porary crossing for civilian application. The analysis was carried out for the bridge loaded with a moving vehicle. The results of this analysis have been developed in the form of nomograms that enable rapid development of crossings in different structural systems.[b]Keywords[/b]: civil engineering, folding bridges, floating supports

  8. Organic field-effect transistor nonvolatile memories utilizing sputtered C nanoparticles as nano-floating-gate

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jie; Liu, Chang-Hai; She, Xiao-Jian; Sun, Qi-Jun; Gao, Xu; Wang, Sui-Dong, E-mail: wangsd@suda.edu.cn [Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123 (China)

    2014-10-20

    High-performance organic field-effect transistor nonvolatile memories have been achieved using sputtered C nanoparticles as the nano-floating-gate. The sputtered C nano-floating-gate is prepared with low-cost material and simple process, forming uniform and discrete charge trapping sites covered by a smooth and complete polystyrene layer. The devices show large memory window, excellent retention capability, and programming/reading/erasing/reading endurance. The sputtered C nano-floating-gate can effectively trap both holes and electrons, and it is demonstrated to be suitable for not only p-type but also n-type organic field-effect transistor nonvolatile memories.

  9. Ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory

    International Nuclear Information System (INIS)

    Han, Jinhua; Wang, Wei; Ying, Jun; Xie, Wenfa

    2014-01-01

    An ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory was demonstrated, with discrete distributed gold nanoparticles, tetratetracontane (TTC), pentacene as the floating-gate layer, tunneling layer, and active layer, respectively. The electron traps at the TTC/pentacene interface were significantly suppressed, which resulted in an ambipolar operation in present memory. As both electrons and holes were supplied in the channel and trapped in the floating-gate by programming/erasing operations, respectively, i.e., one type of charge carriers was used to overwrite the other, trapped, one, a large memory window, extending on both sides of the initial threshold voltage, was realized

  10. Organic field-effect transistor nonvolatile memories utilizing sputtered C nanoparticles as nano-floating-gate

    International Nuclear Information System (INIS)

    Liu, Jie; Liu, Chang-Hai; She, Xiao-Jian; Sun, Qi-Jun; Gao, Xu; Wang, Sui-Dong

    2014-01-01

    High-performance organic field-effect transistor nonvolatile memories have been achieved using sputtered C nanoparticles as the nano-floating-gate. The sputtered C nano-floating-gate is prepared with low-cost material and simple process, forming uniform and discrete charge trapping sites covered by a smooth and complete polystyrene layer. The devices show large memory window, excellent retention capability, and programming/reading/erasing/reading endurance. The sputtered C nano-floating-gate can effectively trap both holes and electrons, and it is demonstrated to be suitable for not only p-type but also n-type organic field-effect transistor nonvolatile memories.

  11. The capture rate of free-floating planets in our galaxy

    Science.gov (United States)

    Goulinski, N.; Ribak, E. N.

    2017-09-01

    We propose that planetary nebulae and supernova remnants may constitute a significant source of free-floating planets. With a large population of free-floating planets, the rate at which these planets get captured by planetary systems may be non-negligible. We predict that about one out of every 100 sub-solar stars are expected to experience a capture of a free-floating planet during their lifetime. The capture cross section calculated through three-body scattering simulations in vacuum conditions. Since planetary systems usually contain multiple planets, and dissipation processes where not included in the simulation, the capture rate may be higher.

  12. Automatic Estimation of Verified Floating-Point Round-Off Errors via Static Analysis

    Science.gov (United States)

    Moscato, Mariano; Titolo, Laura; Dutle, Aaron; Munoz, Cesar A.

    2017-01-01

    This paper introduces a static analysis technique for computing formally verified round-off error bounds of floating-point functional expressions. The technique is based on a denotational semantics that computes a symbolic estimation of floating-point round-o errors along with a proof certificate that ensures its correctness. The symbolic estimation can be evaluated on concrete inputs using rigorous enclosure methods to produce formally verified numerical error bounds. The proposed technique is implemented in the prototype research tool PRECiSA (Program Round-o Error Certifier via Static Analysis) and used in the verification of floating-point programs of interest to NASA.

  13. Floating wind generators offshore wind farm: Implications for structural loads and control actions

    International Nuclear Information System (INIS)

    Garcia, E.; Morant F, Quiles E.; Correcher, A.

    2009-01-01

    This paper describes the work currently carried out in the design of floating wind generators and their involvement in the future development of power generation in marine farms in depths exceeding 20 m. We discuss the main issues to be taken into account in the design of floating platforms, including the involvement of structural loads they bear. Also from a standpoint of control engineering are discussed strategies to reduce structural loads such a system to ensure adequate durability and therefore ensuring their economic viability. Finally, the abstract modeling tools for floating wind turbines that can be used in both structural design and the design of appropriate control algorithms

  14. Influence of Model Simplifications Excitation Force in Surge for a Floating Foundation for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Andersen, Morten Thøtt; Hindhede, Dennis; Lauridsen, Jimmy

    2015-01-01

    As offshore wind turbines move towards deeper and more distant sites, the concept of floating foundations is a potential technically and economically attractive alternative to the traditional fixed foundations. Unlike the well-studied monopile, the geometry of a floating foundation is complex and......, thereby, increases the difficulty in wave force determination due to limitations of the commonly used simplified methods. This paper deals with a physical model test of the hydrodynamic excitation force in surge on a fixed three-columned structure intended as a floating foundation for offshore wind...

  15. Numerical Simulation of Floating Bodies in Extreme Free Surface Waves

    Science.gov (United States)

    Hu, Zheng Zheng; Causon, Derek; Mingham, Clive; Qiang, Ling

    2010-05-01

    A task of the EPSRC funded research project 'Extreme Wave loading on Offshore Wave Energy Devices: a Hierarchical Team Approach' is to investigate the survivability of two wave energy converter (WEC) devices Pelamis and the Manchester Bobber using different CFD approaches. Both devices float on the water surface, generating the electricity from the motion of the waves. In this paper, we describe developments of the AMAZON-SC 3D numerical wave tank (NWT) to study extreme wave loading of a fixed or floating (in Heave motion) structure. The extreme wave formulation as an inlet condition is due to Dalzell (1999) and Ning et. al. (2009) in which a first or second-order Stokes focused wave can be prescribed. The AMAZON-SC 3D code (see e.g. Hu et al. (2009)) uses a cell centred finite volume method of the Godunov-type for the space discretization of the Euler and Navier Stokes equations. The computational domain includes both air and water regions with the air/water boundary captured as a discontinuity in the density field thereby admitting the break up and recombination of the free surface. Temporal discretisation uses the artificial compressibility method and a dual time stepping strategy to maintain a divergence free velocity field. Cartesian cut cells are used to provide a fully boundary-fitted gridding capability on an regular background Cartesian grid. Solid objects are cut out of the background mesh leaving a set of irregularly shaped cells fitted to the boundary. The advantages of the cut cell approach have been outlined previously by Causon et al. (2000, 2001) including its flexibility for dealing with complex geometries whether stationary or in relative motion. The field grid does not need to be recomputed globally or even locally for moving body cases; all that is necessary is to update the local cut cell data at the body contour for as long as the motion continues. The handing of numerical wave paddles and device motion in a NWT is therefore straightforward

  16. Near-Real Time Monthly Global Temperature and Salinity Gridded Data from New Ocean Exploration by Argo Floats

    Science.gov (United States)

    Chu, P. C.; Sun, L.; Fan, C.

    2010-12-01

    New ocean exploration by Argo floats provides sufficient spatial and temporal coverage for sampling the global ocean temperature and salinity. Currently, there are 3193 Argo floats all over the world oceans. Combined with traditionally sampled data, they are included into the Global Temperature and Salinity Profile Program (GTSPP). To fully understanding the variability in ocean thermohaline structure and then its effects on climate variability needs a sufficient resolution in space and, especially, in time, gridded ocean temperature and salinity (T, S) dataset. We analyzed observational profiles (from Argo and traditional technologies) from the GTSPP and produced a T-S data set to meet the above need. GTSPP is a joint programme of the International Oceanographic Data and Information Exchange committee (IODE) and the Joint Commission on Oceanography and Marine Meteorology (JCOMM). IODE and JCOMM are technical committees of the Intergovernmental Oceanographic Commission and the World Meteorological Organization. The quality control procedures used in GTSPP were developed by the Marine Environmental Data Service (MEDS), now the Integrated Science Data Management (ISDM), of Canada. The GTSPP handles all temperature and salinity profile data. This includes observations collected using water samplers, continuous profiling instruments such as Argo, CTDs, thermistor chain data and observations acquired using thermosalinographs. These data will reach data processing centres of the Program through the real-time channels of the IGOSS program or in delayed mode through the IODE system. Real-time data in GTSPP are acquired from the Global Telecommunications System in the bathythermal (BATHY) and temperature, salinity & current (TESAC) codes forms supported by the WMO. Delayed mode data are contributed directly by member states of IOC. Any variable (temperature, salinity, or velocity) can be decomposed into generalized Fourier series using the recently developed optimal

  17. Estimation of Structure-Borne Noise Reduction Effect of Steel Railway Bridge Equipped with Floating Ladder Track and Floating Reinforced-Concrete Deck

    Science.gov (United States)

    Watanabe, Tsutomu; Sogabe, Masamichi; Asanuma, Kiyoshi; Wakui, Hajime

    A number of steel railway bridges have been constructed in Japan. Thin steel members used for the bridges easily tend to vibrate and generate structure-borne noise. Accordingly, the number of constructions of steel railway bridges tends to decrease in the urban areas from a viewpoint of environmental preservation. Then, as a countermeasure against structure-borne noise generated from steel railway bridges, we have developed a new type of the steel railway bridge equipped with a floating-ladder track and a floating reinforced-concrete (RC) deck. As a result of train-running experiment, it became apparent that the new steel railway bridge installed by double floating system has reduced a vibration velocity level by 10.5 dB(A) at main girder web as compared with a steel railway bridge installed by directly fastened track. This reduction effect was achieved by the ladder track and RC deck supported by resilient materials.

  18. Design of 100 MW LNG Floating Barge Power Plant

    Directory of Open Access Journals (Sweden)

    I Made Ariana

    2017-06-01

    Full Text Available Floating bargepower plant able to supply amount of electricity to undeveloped island in Indonesia. In this research, the generator will be use in the power plant is dual-fuel engine. The process was determine the engine and every equipment along with its configuration then arrange the equipment. The result, MAN18V51/60DF selected along with its system configuration and its general arrangement. The final design enable 7.06 days of operation with daily average load (64.76 MW or 4.57 days with continues 100 MW load. In the end, the mobile power plant can be built on Damen B32SPo9832 Barge and comply with the regulation floating bargepower plant able to supply amount of electricity to undeveloped island in Indonesia. In this research, the generator will be use in the power plant is dual-fuel engine. The process was determine the engine and every equipment along with its configuration then arrange the equipment. The result, MAN18V51/60DF selected along with its system configuration and its general arrangement. The final design enable 7.06 days of operation with daily average load (64.76 MW or 4.57 days with continues 100 MW load. In the end, the mobile power plant can be built on Damen B32SPo9832 Barge and comply with the regulation Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  19. Combined Atmospheric and Ocean Profiling from an Airborne High Spectral Resolution Lidar

    Directory of Open Access Journals (Sweden)

    Hair Johnathan

    2016-01-01

    Full Text Available First of its kind combined atmospheric and ocean profile data were collected by the recently upgraded NASA Langley Research Center’s (LaRC High Spectral Resolution Lidar (HSRL-1 during the 17 July – 7 August 2014 Ship-Aircraft Bio-Optical Research Experiment (SABOR. This mission sampled over a region that covered the Gulf of Maine, open-ocean near Bermuda, and coastal waters from Virginia to Rhode Island. The HSRL-1 and the Research Scanning Polarimeter from NASA Goddard Institute for Space Studies collected data onboard the NASA LaRC King Air aircraft and flight operations were closely coordinated with the Research Vessel Endeavor that made in situ ocean optical measurements. The lidar measurements provided profiles of atmospheric backscatter and particulate depolarization at 532nm, 1064nm, and extinction (532nm from approximately 9km altitude. In addition, for the first time HSRL seawater backscatter, depolarization, and diffuse attenuation data at 532nm were collected and compared to both the ship measurements and the Moderate Resolution Imaging Spectrometer (NASA MODIS-Aqua satellite ocean retrievals.

  20. Tripolyphosphate-crosslinked chitosan/poly (ethylene oxide) electrospun nanofibrous mats as a floating gastro-retentive delivery system for ranitidine hydrochloride.

    Science.gov (United States)

    Darbasizadeh, Behzad; Motasadizadeh, Hamidreza; Foroughi-Nia, Behrouz; Farhadnejad, Hassan

    2018-05-10

    The present study describes the fabrication of Tripolyphosphate (TPP)-crosslinked nanofibrous mats based on chitosan for use as a floating gastro-retentive delivery system. TPP-crosslinked chitosan (CH)/poly (ethylene oxide) (PEO)- ranitidine hydrochloride (RH) electrospun nanofibers (75.27 ± 2.10 nm) were prepared by electrospinning 70% v/v acetic acid solutions, and followed by crosslinking by TPP anions. The mechanical, structural and morphological properties of the prepared nanofibers were evaluated via tensile testing, XRD, FT-IR, TGA, NMR, AFM and SEM experimental techniques. The prepared nanofibrous mats showed a pH sensitive swelling profile with maximum water absorbing at pH 1.2. Results obtained from above experimental techniques indicated that crosslinking process did not significantly altered morphological property of nanofibers but rather decreased their diameter and swelling degree, and increased their mechanical properties, thermal stability and bioadhesive strength. Viscosity measurements showed that the addition of PEO and RH to the chitosan solution, depending to its concentration lead to decrease in the viscosity of its solution. Also, floating test showed that the prepared nanofibrous mats remain floated onto surface of the dissolution medium for more than 48 h. Based on in- vitro drug release data analysis, TPP-crosslinked CH/PEO nanofibrous mats decreased initial burst release and it was exhibited a sustained release profile for the RH from the TPP-crosslinked CH/PEO-RH electrospun nanofibrous mats. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. FLOAT - development of new flexible UHPC. Final report. [Ultra High Performance Fibre Reinforced Concrete

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    The current project is a preliminary study intended to clarify the background and give a better basis for an evaluation of the risks and possible rewards of funding a full project with the overall purpose of developing and testing a new concept for wave energy floaters, made of Ultra High Performance Fibre Reinforced Concrete (UHPC), as an enabling technology for the establishment of competitive wave energy production (FLOAT). As an initial step for this preliminary study of FLOAT an investigation has been undertaken in relation to preliminary design of 2 types of floaters, essential properties of UHPFRC - and identification of necessary developments, compilation of existing data from off shore applications and analysis of effect on Cost Of Energy. Preliminary float design and economical considerations - is a theoretical and numerical study including preliminary float designs and cost estimates. It aims at making a first comparison between the different materials options for DEXA and Wave Star floats and giving a first judgement about the suitability of CRC concrete. This is done through a qualitative assessment of pros and cons of different materials for both types of floats and a design study of the Dexa Wave float. It is concluded that the requirements for the Dexa Wave float are so that CRC is not able to compete with conventional concrete for the best and most cost effective solution. The good durability (leading to low maintenance costs), the mechanical properties and the ductility of CRC are not important enough to offset the increased cost for this float. For Wave Star on the other hand, there are significant advantages in using CRC as the only other option in this case is fibre glass, which is a much more expensive product. An investigation was made of methods of optimizing the properties of CRC - customizing them for particular applications in WEC's. The method of optimization has been to change the types of fibres in the mix, and it is demonstrated

  2. Assessment of floating plastic debris in surface water along the Seine River.

    Science.gov (United States)

    Gasperi, Johnny; Dris, Rachid; Bonin, Tiffany; Rocher, Vincent; Tassin, Bruno

    2014-12-01

    This study is intended to examine the quality and quantity of floating plastic debris in the River Seine through use of an extensive regional network of floating debris-retention booms; it is one of the first attempts to provide reliable information on such debris at a large regional scale. Plastic debris represented between 0.8% and 5.1% of total debris collected by weight. A significant proportion consisted of food wrappers/containers and plastic cutlery, probably originating from voluntary or involuntary dumping, urban discharges and surface runoff. Most plastic items are made of polypropylene, polyethylene and, to a lesser extent, polyethylene terephthalate. By extrapolation, some 27 tons of floating plastic debris are intercepted annually by this network; corresponding to 2.3 g per Parisian inhabitant per year. Such data could serve to provide a first evaluation of floating plastic inputs conveyed by rivers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. uG-LilyPond - Floating Plant Pond for Microgravity, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed μG-LilyPond is an autonomous environmentally controlled floating plant cultivation system for use in microgravity. The μG-LilyPond concept expands the...

  4. Stress and deflection analyses of floating roofs based on a load-modifying method

    International Nuclear Information System (INIS)

    Sun Xiushan; Liu Yinghua; Wang Jianbin; Cen Zhangzhi

    2008-01-01

    This paper proposes a load-modifying method for the stress and deflection analyses of floating roofs used in cylindrical oil storage tanks. The formulations of loads and deformations are derived according to the equilibrium analysis of floating roofs. Based on these formulations, the load-modifying method is developed to conduct a geometrically nonlinear analysis of floating roofs with the finite element (FE) simulation. In the procedure with the load-modifying method, the analysis is carried out through a series of iterative computations until a convergence is achieved within the error tolerance. Numerical examples are given to demonstrate the validity and reliability of the proposed method, which provides an effective and practical numerical solution to the design and analysis of floating roofs

  5. Floating harmonic probe measurements in the low-temperature plasma jet deposition system

    Science.gov (United States)

    Zanáška, M.; Hubička, Z.; Čada, M.; Kudrna, P.; Tichý, M.

    2018-01-01

    The floating harmonic probe is a relatively new plasma diagnostic method, which was proposed for applications at conditions when insulating films are deposited on the probe and, consequently, the classical Langmuir probe method fails. In the floating harmonic probe method a purely sinusoidal AC voltage is applied to the probe constructed in a standard manner via a capacitor. From the spectral components of the measured AC probe current waveforms, the electron temperature and the positive ion density can be obtained. In this contribution we present the comparison of the electron temperature and density acquired by the floating harmonic probe method with those obtained by the classical Langmuir probe. The experiments are performed in the flowing DC discharge in argon. In addition, the results from the floating harmonic probe method obtained during deposition of an insulating iron oxide thin film are shown. All the data is complemented by the qualitative discussion.

  6. Floating nuclear energy plants for seawater desalination. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    1997-05-01

    Floating nuclear desalination facilities are one of the alternatives being considered. They may offer a particularly suitable choice for remote locations and small island or coastal communities where the necessary manpower and infrastructure to support desalination plants are not available. In the interest of focusing specific attention on the technology of floating nuclear desalination, the IAEA sponsored a Technical Committee Meeting on Floating Nuclear Plants for Seawater Desalination from 29 to 31 May 1995 in Obninsk, Russian Federation. This publication documents the papers and presentations given by experts from several countries at that meeting. It is hoped that the information contained in this report will be a valuable resource for those interested in nuclear desalination, and that it will stimulate further interest in the potential for floating nuclear desalination facilities. Refs, figs, tabs

  7. Photobleaching Kinetics of Chromophoric Dissolved Organic Matter Derived from Mangrove Leaf Litter and Floating Sargassum Colonies

    Science.gov (United States)

    We examined the photoreactivity of chromophoric dissolved organic matter (CDOM) derived from Rhizophora mangle (red mangrove) leaf litter and floating Sargassum colonies as these marine plants can be important contributors to coastal and open ocean CDOM pools, respectively. Mangr...

  8. Warm Water Pathways in the Northeastern North Atlantic ACCE RAFOS Float Data Report

    National Research Council Canada - National Science Library

    Furey, Heather

    2001-01-01

    ...). The RAFOS float component of ACCE, entitled "Warm Water Pathways and Intergyre Exchange in the Northeastern North Atlantic", was designed to measure the warm water currents entering the northeastern...

  9. Warm Water Pathways in the Northeastern North Atlantic ACCE RAFOS Float Data Report

    National Research Council Canada - National Science Library

    Furey, Heather

    2001-01-01

    This is the final data report of all acoustically tracked RAFOS float data collected by the Woods Hole Oceanographic Institution in 1996-1997 during the Atlantic Circulation and Climate Experiment (ACCE...

  10. Surface and Internal Waves due to a Moving Load on a Very Large Floating Structure

    Directory of Open Access Journals (Sweden)

    Taro Kakinuma

    2012-01-01

    Full Text Available Interaction of surface/internal water waves with a floating platform is discussed with nonlinearity of fluid motion and flexibility of oscillating structure. The set of governing equations based on a variational principle is applied to a one- or two-layer fluid interacting with a horizontally very large and elastic thin plate floating on the water surface. Calculation results of surface displacements are compared with the existing experimental data, where a tsunami, in terms of a solitary wave, propagates across one-layer water with a floating thin plate. We also simulate surface and internal waves due to a point load, such as an airplane, moving on a very large floating structure in shallow water. The wave height of the surface or internal mode is amplified when the velocity of moving point load is equal to the surface- or internal-mode celerity, respectively.

  11. Wind Turbine Controller to Mitigate Structural Loads on a Floating Wind Turbine Platform

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Paul A.; Peiffer, Antoine; Schlipf, David

    2016-06-24

    This paper summarizes the control design work that was performed to optimize the controller of a wind turbine on the WindFloat structure. The WindFloat is a semi-submersible floating platform designed to be a support structure for a multi-megawatt power-generating wind turbine. A controller developed for a bottom-fixed wind turbine configuration was modified for use when the turbine is mounted on the WindFloat platform. This results in an efficient platform heel resonance mitigation scheme. In addition several control modules, designed with a coupled linear model, were added to the fixed-bottom baseline controller. The approach was tested in a fully coupled nonlinear aero-hydroelastic simulation tool in which wind and wave disturbances were modeled. This testing yielded significant improvements in platform global performance and tower-base-bending loading.

  12. Is there foul play in the leaf pocket? The metagenome of floating fern

    NARCIS (Netherlands)

    Dijkhuizen, L.W.; Brouwer, P.; Bolhuis, H.; Reichart, G.-J.; Koppers, N.; Huettel, B.; Bolger, A.M.; Li, F.-W.; Cheng, S.; Liu, X.; Wong, G.K.-S.; Pryer, K.; Weber, A.; Bräutigam, A.; Schluepmann, H.

    2018-01-01

    Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolificgrowth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms,the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associatedwith Azolla ferns

  13. Effect analysis of geometric parameters of floating raft on isolation performance

    Directory of Open Access Journals (Sweden)

    LI Shangda

    2017-12-01

    Full Text Available [Objectives] This paper focuses on the effects of the geometric parameters of a floating raft on isolation performance.[Methods] Based on the idea that the weight of a floating raft remains constant, a parametric finite element model is established using geometric parameters, and the effects of the geometric parameters when isolation performance is measured by vibration level difference are discussed.[Results] The effects of the geometric parameters of a floating raft on isolation performance are mainly reflected in the middle and high frequency areas. The most important geometric parameters which have an impact on isolation performance are the raft's height, length to width ratio and number of ribs. Adjusting the geometric parameters of the raft is one effective way to avoid the vibration frequency of mechanical equipment.[Conclusions] This paper has some practical value for the engineering design of floating raft isolation systems.

  14. A new floating frame of reference formulation for flexible multibody dynamics

    NARCIS (Netherlands)

    Schilder, Jurnan Paul

    2017-01-01

    For the dynamic analysis of flexible multibody systems, three conceptually different descriptions are available and commonly used: the inertial frame formulations, the corotational formulations and the floating frame formulations. The differences between these formulations are mainly in the way they

  15. Estimating transmitted waves of floating breakwater using support vector regression model

    Digital Repository Service at National Institute of Oceanography (India)

    Mandal, S.; Hegde, A.V.; Kumar, V.; Patil, S.G.

    Planning and design of coastal protection works like floating breakwaters requires information about the performance characteristics of the structure in reducing the wave energy. They can be used as a temporary protection for offshore activities...

  16. Significance of relative velocity in drag force or drag power estimation for a tethered float

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Sastry, J.S.

    There is difference in opinion regarding the use of relative velocity instead of particle velocity alone in the estimation of drag force or power. In the present study, a tethered spherical float which undergoes oscillatory motion in regular waves...

  17. Recovery of uranium from seawater using wave power and floating offshore units

    International Nuclear Information System (INIS)

    Bjoerk, B.; Vallander, P.

    1981-06-01

    This report is a final contribution to a study of the technical and economic feasibility of floating units for the recovery of uranium from seawater. The seawater is supplied by wave energy and received by a sloping plane. An optimization was carried out which involved study of the number of storeys of adsorbent beds in a floating unit, the number and tonnage of service vessels and the number of moorings. Different adsorbent bed areas, thickness of layers of adsorbent material, length of floating units and length of extraction cycles were considered. The costs of a plant for each combination of optimization parameters were calculated and are presented. The most feasible offshore plant will recover uranium at a cost of about 1900 SEK/kg. It will comprise 22 floating units, each with an adsorbent bed area of 300 m 2 per metre of the unit and an adsorbent thickness of 0.10 metres. (Authors)

  18. Application of a movable active vibration control system on a floating raft

    Science.gov (United States)

    Wang, Zhen; Mak, Cheuk Ming

    2018-02-01

    This paper presents a theoretical study of an inertial actuator connected to an accelerometer by a local feedback loop for active vibration control on a floating raft. On the criterion of the minimum power transmission from the vibratory machines to the flexible foundation in the floating raft, the best mounting positions for the inertial actuator on the intermediate mass of the floating raft are investigated. Simulation results indicate that the best mounting positions for the inertial actuator vary with frequency. To control time-varying excitations of vibratory machines on a floating raft effectively, an automatic control system based on real-time measurement of a cost function and automatically searching the best mounting position of the inertial actuator is proposed. To the best of our knowledge, it is the first time that an automatic control system is proposed to move an actuator automatically for controlling a time-varying excitation.

  19. Challenges in Simulation of Aerodynamics, Hydrodynamics, and Mooring-Line Dynamics of Floating Offshore Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Matha, D.; Schlipf, M.; Cordle, A.; Pereira, R.; Jonkman, J.

    2011-10-01

    This paper presents the current major modeling challenges for floating offshore wind turbine design tools and describes aerodynamic and hydrodynamic effects due to rotor and platform motions and usage of non-slender support structures.

  20. Applicability of linear and non-linear potential flow models on a Wavestar float

    DEFF Research Database (Denmark)

    Bozonnet, Pauline; Dupin, Victor; Tona, Paolino

    2017-01-01

    Numerical models based on potential flow theory, including different types of nonlinearities are compared and validated against experimental data for the Wavestar wave energy converter technology. Exact resolution of the rotational motion, non-linear hydrostatic and Froude-Krylov forces as well...... control action, limited to small amplitude motion with a single float, is well predicted by the numerical models, including the linear one. Still, float velocity is better predicted by accounting for non-linear hydrostatic and Froude-Krylov forces....

  1. Development of floating cover constructions for pond heat storage; Udvikling af flydende laagkonstruktioner til damvarmelagre. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Duer, K. (ed.)

    2000-07-01

    The purpose of the project was to carry out a sketch project of the new cover designs for heat storage in ponds that were developed in phase II of the project. In parallel to the sketch project minor laboratory tests were carried out in order to investigate critical details of the floating cover designs. Two types of floating covers were investigated: One of plastics and two versions based on steel. (EHS)

  2. The Grand Canyon of the Colorado: a challenge to float, a challenge to manage

    Science.gov (United States)

    David N. Cole

    1989-01-01

    Last summer, I finally got my chance to float the Colorado River through the Grand Canyon, one of the world’s premier adventure trips. For 18 days and 280 miles, my group floated through some of the most spectacular scenery imaginable, spacing our days with hikes through slickrock alcoves, along terraced pools of blue-green water, to waterfalls plunging out of holes on...

  3. Formulation of gastroretentive floating drug delivery system using hydrophilic polymers and its in vitro characterization

    OpenAIRE

    Meka, Venkata Srikanth; Dharmanlingam, Senthil Rajan; Kolapalli, Venkata Ramana Murthy

    2014-01-01

    The aim of the present research is to formulate and evaluate the gastroretentive floating drug delivery system of antihypertensive drug, propranolol HCl. Gastroretentive floating tablets (GRFT) were prepared by using a synthetic hydrophilic polymer polyethylene oxide of different grades such as PEO WSR N-12 K and PEO 18 NF as release retarding polymers and calcium carbonate as gas generating agent. The GRFT were compressed by direct compression strategy and the tablets were evaluated for phys...

  4. Enhanced Bioavailability and Dissolution of Atorvastatin Calcium from Floating Microcapsules using Minimum Additives

    OpenAIRE

    Khan, Furquan Nazimuddin; Dehghan, Mohamed Hassan G.

    2011-01-01

    Atorvastatin calcium, a lipid-lowering drug, is much less bioavailable because of reduced solubility in acidic media. Multiple-unit floating microcapsules of Atorvastatin calcium (ATC) were developed to expand the gastric residence time of the drug, as ATC has maximum rate of absorption in the upper GI tract. Floating microcapsules were prepared by Emulsion-solvent evaporation technique through incorporation of dioctyl sodium sulphosuccinate (DSS) as a dissolution enhancer. The microcapsules ...

  5. Formulation optimization of floating microbeads containing modified Chinese yam starch using factorial design

    OpenAIRE

    Adenike Okunlola; Oluwatoyin A Odeku; Rakesh P. Patel

    2012-01-01

    Controlled release floating metformin hydrochloride microbeads were prepared and optimized using a blend of varying concentrations of freeze-dried pregelatinized Chinese yam starch (Dioscorea oppositifolia L) and sodium alginate. Floating microbeads were prepared by the ionotropic gelation method using 10% w/v calcium chloride as the cross-linking agent and sodium bicarbonate as the gas releasing agent. A full 32 factorial design was used to investigate the influence of two variables: concent...

  6. Collective cell behavior on basement membranes floating in space

    Science.gov (United States)

    Ellison, Sarah; Bhattacharjee, Tapomoy; Morley, Cameron; Sawyer, W.; Angelini, Thomas

    The basement membrane is an essential part of the polarity of endothelial and epithelial tissues. In tissue culture and organ-on-chip devices, monolayer polarity can be established by coating flat surfaces with extracellular matrix proteins and tuning the trans-substrate permeability. In epithelial 3D culture, spheroids spontaneously establish inside-out polarity, morphing into hollow shell-like structures called acini, generating their own basement membrane on the inner radius of the shell. However, 3D culture approaches generally lack the high degree of control provided by the 2D culture plate or organ-on-chip devices, making it difficult to create more faithful in vitro tissue models with complex surface curvature and morphology. Here we present a method for 3D printing complex basement membranes covered in cells. We 3D print collagen-I and Matrigel into a 3D growth medium made from jammed microgels. This soft, yielding material allows extracellular matrix to be formed as complex surfaces and shapes, floating in space. We then distribute MCF10A epithelial cells across the polymerized surface. We envision employing this strategy to study 3D collective cell behavior in numerous model tissue layers, beyond this simple epithelial model.

  7. Debate - Trafficking as a Floating Signifier: The view from Brazil

    Directory of Open Access Journals (Sweden)

    Grupo Davida

    2015-04-01

    Full Text Available The fact that the United Nations (UN Trafficking Protocol is not an autochthonous product of the Brazilian political system has resulted in its being brought into that system as a ‘floating signifier’: something that does not point to any actual object or agreed upon meaning.[1] People who wish to criminalise prostitution have attempted to bend the Protocol in that direction while prostitutes’ rights groups have used it to critique current Brazilian laws, emphasising the need to distinguish migration for voluntary, consensual sex work from trafficking. Groups concerned with organ trafficking (a crime for which there are practically no proven cases in Brazil have managed to push their banner to the fore in the trafficking debate. Meanwhile, Brazil’s long-established and relatively successful anti-slave labour movement has been loath to ‘change their brand’, having already gained a considerable degree of institutionalisation prior to Brazil’s ratification of the Protocol in 2004. [1] C Lévi-Strauss, ‘Introduction à l'oeuvre de Marcel Mauss’ in Mauss, Sociologie et Anthropologie, Paris, 1950.

  8. Floating of Black Holes in Dimension of Information

    Science.gov (United States)

    Gholibeigian, Hassan; Gholibeigian, Ghasem; Gholibeigian, Kazem

    2016-10-01

    In our vision, there is dimension of information in addition of space-time's dimensions as the fifth dimension of the universe. All of the space-time, mater, and dark mater/energy are always floating in this dimension and whispering to its communication as well as black holes. Communication of information (CI) is done with each fundamental particle (string) from fifth dimension via its four animated sub-particles (sub-strings) for transferring a package of complete information of its quantum state in a Planck time. Fundamental particle after process of information by its sub-particles goes to its next stage while carries the stored processed information. CI as the ``fundamental symmetry'' leads all processes of the black holes as well as other phenomena. Every point of space-time needs on time to its new package, because duration of each processing is a Planck time. So, stored soft super-translation hairs in terms of soft gravitons or photons on black hole's horizon, or stored information on a holographic plate at the future boundary of the horizon [Hawking et al.] can be only accessible for particles which are in those positions (horizon and its boundary), not for other locations of black hole for their fast processing. AmirKabir University of Technology, Tehran, Iran.

  9. Hydroelastic response of a floating runway to cnoidal waves

    International Nuclear Information System (INIS)

    Ertekin, R. C.; Xia, Dingwu

    2014-01-01

    The hydroelastic response of mat-type Very Large Floating Structures (VLFSs) to severe sea conditions, such as tsunamis and hurricanes, must be assessed for safety and survivability. An efficient and robust nonlinear hydroelastic model is required to predict accurately the motion of and the dynamic loads on a VLFS due to such large waves. We develop a nonlinear theory to predict the hydroelastic response of a VLFS in the presence of cnoidal waves and compare the predictions with the linear theory that is also developed here. This hydroelastic problem is formulated by directly coupling the structure with the fluid, by use of the Level I Green-Naghdi theory for the fluid motion and the Kirchhoff thin plate theory for the runway. The coupled fluid structure system, together with the appropriate jump conditions are solved in two-dimensions by the finite-difference method. The numerical model is used to study the nonlinear response of a VLFS to storm waves which are modeled by use of the cnoidal-wave theory. Parametric studies show that the nonlinearity of the waves is very important in accurately predicting the dynamic bending moment and wave run-up on a VLFS in high seas

  10. Mass and charge transfer within a floating water bridge

    Science.gov (United States)

    Fuchs, Elmar C.; Agostinho, Luewton L. F.; Eisenhut, Mathias; Woisetschläger, Jakob

    2010-11-01

    When high voltage is applied to pure water filled into two beakers close to each other, a connection forms spontaneously, giving the impression of a floating water bridge 1-8. This phenomenon is of special interest, since it comprises a number of phenomena currently tackled in modern water science. In this work, the charge and mass transfer through the water bridge are investigated with schlieren visualization and laser interferometry. It can be shown that the addition of a pH dye increases the H+ and OH- production with subsequent electrolysis, whereas schlieren and interferometric methods reveal another mechanism where charge and mass transfer appear to be coupled. Whereas this mechanism seems to be responsible for the electrolysis-less charge and mass transfer in the water bridge, it is increasingly superseded by the electrochemical mechanism with rising conductivity. Thus it can be shown that a pH dye does only indirectly visualize the charge transfer in the water bridge since it is dragged along with the water flow like any other dye, and additionally promotes conventional electrochemical conduction mechanisms, thereby enhancing electrolysis and reducing the masscoupled charge transport and thus destabilizing the bridge.

  11. Spectral target detection for detecting and characterizing floating marine debris

    Science.gov (United States)

    Harris, T.; Streett, D.; Belge, J.; Hulslander, D.; Ramirez, E.; Jankot, J.; Vogt, J.; Kamphaus, B.

    2012-12-01

    On March 11, 2011, a devastating 9.0 earthquake and tsunami struck Japan, claiming nearly 16,000 lives and injuring 6,000. In the following weeks large amounts of debris comprised of man-made structures and vegetation could be seen off the east coast of Japan using multiple satellite sensors. NOAA Marine Debris Program expects a portion of this debris to reach U.S. and Canadian shores over the next several years. NOAA Satellite Analysis Branch and Exelis Visual Information Solutions have led efforts to identify and assess the spatial distribution of floating marine debris across the Pacific Ocean and near the west coast of the United States. This work will provide information to groups that are aiming to mitigate possible impacts to natural resources and coastal communities. An advanced methodology is being developed and applied for remote sensing target detection of debris using spectral properties of high resolution multispectral imagery from the WorldView-2 satellite. Preliminary results are presented .

  12. Floating Classroom Outreach as an Introduction to Ocean Studies

    Science.gov (United States)

    McFadden, M.

    2016-02-01

    Many children and young adults living within only one hour of the coast never have the opportunity to explore a beach or go out on a boat because of financial challenges or lack of transportation.These types of experiences are the spark that helped many ocean scientists become fascinated with the ocean and later pursue a career related to the ocean. This presentation will discuss a variety of outreach projects and the efficacy of each. Projects vary in age, complexity and cost. These projects include a Beach Clean-Up open to students and their families at a community college organized by a campus volunteer group with a focus on social issues, a Marine Biology and Physical Oceanography class joint floating classroom trip open to college students to introduce non-STEM students to marine science in an exciting setting, and an education outreach trip for 8-12 years old children from the Boys and Girls Club in Newport, RI in collaboration with The International SeaKeepers Society, a non-profit that facilitates ocean research and education by working closely with the yachting community. Emphasis on environmental education in the U.S. has grown considerably over recent years, and the development of unique and innovative approaches to hands-on marine science education are needed to excite students to explore the marine environment and care about environmental stewardship.

  13. Automated Incident Detection Using Real-Time Floating Car Data

    Directory of Open Access Journals (Sweden)

    Maarten Houbraken

    2017-01-01

    Full Text Available The aim of this paper is to demonstrate the feasibility of a live Automated Incident Detection (AID system using only Floating Car Data (FCD in one of the first large-scale FCD AID field trials. AID systems detect traffic events and alert upcoming drivers to improve traffic safety without human monitoring. These automated systems traditionally rely on traffic monitoring sensors embedded in the road. FCD allows for finer spatial granularity of traffic monitoring. However, low penetration rates of FCD probe vehicles and the data latency have historically hindered FCD AID deployment. We use a live country-wide FCD system monitoring an estimated 5.93% of all vehicles. An FCD AID system is presented and compared to the installed AID system (using loop sensor data on 2 different highways in Netherlands. Our results show the FCD AID can adequately monitor changing traffic conditions and follow the AID benchmark. The presented FCD AID is integrated with the road operator systems as part of an innovation project, making this, to the best of our knowledge, the first full chain technical feasibility trial of an FCD-only AID system. Additionally, FCD allows for AID on roads without installed sensors, allowing road safety improvements at low cost.

  14. Potential area for floating net fishery in Lake Toba

    Science.gov (United States)

    Rustini, H. A.; Harsono, E.; Ridwansyah, I.

    2018-02-01

    Lake Toba in North Sumatera, Indonesia, is now designated to be a world-class tourism destination. Aside from its infrastructure development, this largest lake in the Southeast Asia needs to be restored, especially its water quality. While an oligotrophic status is required for tourism purposes, several studies showed that Toba is mesotrophic at its best and hyper-eutrophic at its worst. Numerous studies and reports blame floating net fishery (FNF) for water quality decline in Lake Toba and propose limitation for its production. While the central government allowed FNF to be positioned in certain areas according to its depth and distance from the lakeshore, increasing number of FNF means adding more nutrients to the lake and thus may inhibit the lake’s restoration process. Hence, it is important to identify which areas are potential for FNF location to assist the authorities to regulate FNF. This study used SPOT-6, SPOT-7, and Pleiades satellite imagery to locate the position of existing FNF and to analyse the result to identify a potential location for FNF.

  15. Orchid woods and floating islands - the ecology of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, P. [Roehampton Institute, London (United Kingdom)

    1994-02-01

    The article reviews the ecology of disused pulverised fuel ash (PFA) from fossil-fuel power plants and suggests methods by which PFA can be used as a conservation resource. Plants which grow on weathered PFA are listed. They include mosses and orchids. PFA contains cenopheres which are hollow and buoyant, known as floaters. Those can accumulate as white scum on ash lagoons and can be colonised by aquatic plants which bind at the roots to form floating islands. Examples of sites where this has happened in the UK are given. Banks of PFA have provided resting place for sand martins and digging ground for badgers and foxes. PFA sites need careful management as floral succession progresses. The successional habitats on PFA and other industrial wastes are a declining ecosystem, owing to the advent of tougher waste-disposal legislation, banning the bad old ways of dumping and forgetting. Unless PFA areas start to be specifically created with conservation in mind, it is unlikely that the next generation will ever see orchid glades in a PFA woodland. 24 refs., 6 photos.

  16. High-gain bipolar detector on float-zone silicon

    Science.gov (United States)

    Han, D. J.; Batignani, G.; Del Guerra, A.; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Giorgi, M.; Forti, F.

    2003-10-01

    Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be ˜7.77×10 4/s). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 μm has been observed for the same device.

  17. High-gain bipolar detector on float-zone silicon

    International Nuclear Information System (INIS)

    Han, D.J.; Batignani, G.; Guerra, A.D.A. Del; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Giorgi, M.; Forti, F.

    2003-01-01

    Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be ∼7.77x10 4 /s). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 μm has been observed for the same device

  18. A global inventory of small floating plastic debris

    Science.gov (United States)

    van Sebille, Erik; Wilcox, Chris; Lebreton, Laurent; Maximenko, Nikolai; Hardesty, Britta Denise; van Franeker, Jan A.; Eriksen, Marcus; Siegel, David; Galgani, Francois; Lavender Law, Kara

    2015-12-01

    Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on the North Atlantic and North Pacific accumulation zones, with much sparser coverage elsewhere. Here, we use the largest dataset of microplastic measurements assembled to date to assess the confidence we can have in global estimates of microplastic abundance and mass. We use a rigorous statistical framework to standardize a global dataset of plastic marine debris measured using surface-trawling plankton nets and coupled this with three different ocean circulation models to spatially interpolate the observations. Our estimates show that the accumulated number of microplastic particles in 2014 ranges from 15 to 51 trillion particles, weighing between 93 and 236 thousand metric tons, which is only approximately 1% of global plastic waste estimated to enter the ocean in the year 2010. These estimates are larger than previous global estimates, but vary widely because the scarcity of data in most of the world ocean, differences in model formulations, and fundamental knowledge gaps in the sources, transformations and fates of microplastics in the ocean.

  19. Investigation on Floating Lid Construction, pit Water Storage, Ottrupgaard, Denmark

    DEFF Research Database (Denmark)

    Heller, Alfred

    At Ottrupgaard a pit water storage of 1,500 m3 and a lid area of about 700 m2 is built for seasonal storage of a solar collector field of 560 m2. The lid price is the largest component of a pit water store with a cost share of about 57%, more precisely 1,163 Dkr./m2. Due to the large share in price...... the development of lid constructions is crucial for the development of pit water storage and seasonal storage, as it seems that the development of solar collectors will not have a breakthrough in the near future.The Ottrupgaard lid design is basically a sandwich element construction of PUR-foam between two...... conditions floating on hot water. The test lids were examined for tightness by a number of means. The results showed critical construction errors of the first lid design. A redesigned lid showed acceptable results, but also some water penetration into the lid insulation. The entered water gathers...

  20. Graphene-graphene oxide floating gate transistor memory.

    Science.gov (United States)

    Jang, Sukjae; Hwang, Euyheon; Lee, Jung Heon; Park, Ho Seok; Cho, Jeong Ho

    2015-01-21

    A novel transparent, flexible, graphene channel floating-gate transistor memory (FGTM) device is fabricated using a graphene oxide (GO) charge trapping layer on a plastic substrate. The GO layer, which bears ammonium groups (NH3+), is prepared at the interface between the crosslinked PVP (cPVP) tunneling dielectric and the Al2 O3 blocking dielectric layers. Important design rules are proposed for a high-performance graphene memory device: (i) precise doping of the graphene channel, and (ii) chemical functionalization of the GO charge trapping layer. How to control memory characteristics by graphene doping is systematically explained, and the optimal conditions for the best performance of the memory devices are found. Note that precise control over the doping of the graphene channel maximizes the conductance difference at a zero gate voltage, which reduces the device power consumption. The proposed optimization via graphene doping can be applied to any graphene channel transistor-type memory device. Additionally, the positively charged GO (GO-NH3+) interacts electrostatically with hydroxyl groups of both UV-treated Al2 O3 and PVP layers, which enhances the interfacial adhesion, and thus the mechanical stability of the device during bending. The resulting graphene-graphene oxide FGTMs exhibit excellent memory characteristics, including a large memory window (11.7 V), fast switching speed (1 μs), cyclic endurance (200 cycles), stable retention (10(5) s), and good mechanical stability (1000 cycles). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. What´s floating on my plasma?

    Science.gov (United States)

    Cadamuro, Janne; Wiedemann, Helmut; Felder, Thomas K; Mrazek, Cornelia; Kipman, Ulrike; Hannes, Oberkofler; Haschke-Becher, Elisabeth

    2017-06-15

    We report on a preanalytical issue we encountered during routine clinical chemistry analyses, potentially leading to deviated analysis results and believe that it might help other laboratories to overcome similar problems. In a heparin-gel tube we measured an implausible glucose value of 0.06 mmol/L. Re-measurement of the same sample resulted in a glucose value of 5.4 mmol/L. After excluding an analytical error, we inspected the sample closer and found a white material as well as fatty droplets floating on the surface of the plasma tube. Evaluation of these structures revealed that the white particulate matter (WPM) consisted of fibrinogen, platelets and leukocytes and the fatty droplets most probably originated from the separator gel. We concluded that these structures formed a temporary clot in the instruments pipetting needle thereby altering the sampling volume and subsequently the measured glucose value. The formation of WPM might be attributable to high speed centrifugation, high cholesterol levels, the gel formulation or a combination of several issues such as temperature, heparin concentration, pH and patient-specific factors. The gel droplets were most probably caused by an aberrant gel formulation in combination with an improper storage of the empty tubes on the wards prior to phlebotomy. After adding an additional instrument cleansing cycle and changing to another batch of heparin tubes the problems could be significantly reduced.

  2. Interactive floating windows: a new technique for stereoscopic video games

    Science.gov (United States)

    Zerebecki, Chris; Stanfield, Brodie; Tawadrous, Mina; Buckstein, Daniel; Hogue, Andrew; Kapralos, Bill

    2012-03-01

    The film industry has a long history of creating compelling experiences in stereoscopic 3D. Recently, the video game as an artistic medium has matured into an effective way to tell engaging and immersive stories. Given the current push to bring stereoscopic 3D technology into the consumer market there is considerable interest to develop stereoscopic 3D video games. Game developers have largely ignored the need to design their games specifically for stereoscopic 3D and have thus relied on automatic conversion and driver technology. Game developers need to evaluate solutions used in other media, such as film, to correct perceptual problems such as window violations, and modify or create new solutions to work within an interactive framework. In this paper we extend the dynamic floating window technique into the interactive domain enabling the player to position a virtual window in space. Interactively changing the position, size, and the 3D rotation of the virtual window, objects can be made to 'break the mask' dramatically enhancing the stereoscopic effect. By demonstrating that solutions from the film industry can be extended into the interactive space, it is our hope that this initiates further discussion in the game development community to strengthen their story-telling mechanisms in stereoscopic 3D games.

  3. Dynamics of Under Ice Boundary Layers Below Floating Ice Shelves

    Science.gov (United States)

    Shaw, W. J.; Stanton, T. P.

    2016-02-01

    Pine Island Glacier (PIG), a major outlet stream of the Western Antarctic Ice Sheet, has dramatically thinned and accelerated in recent decades. It is believed that a weakening of the floating portion of the glacier, known as the ice shelf, due to increased ocean thermal forcing is a primary cause of the observed increasing discharge of PIG. In order to better understand the controls on the exchange of heat between the PIG shelf and the underlying ocean cavity, a numerical model, MITgcm, has been configured to study the dynamics of the sloping, meltwater-forced, buoyant boundary layer below the ice shelf A 2-D approximation allows for high vertical resolution that resolves well the under shelf ocean boundary layer. We are particularly interested in the dynamical balance between buoyancy along the sloping ice shelf base, drag, and entrainment/detrainment and the associated feedback of basal melting of the ice shelf. Numerical results will be compared to in-situ observations obtained through a field campaign in 2013.

  4. Measuring the Coefficient of Friction of a Small Floating Liquid Marble.

    Science.gov (United States)

    Ooi, Chin Hong; Nguyen, Anh Van; Evans, Geoffrey M; Dao, Dzung Viet; Nguyen, Nam-Trung

    2016-12-02

    This paper investigates the friction coefficient of a moving liquid marble, a small liquid droplet coated with hydrophobic powder and floating on another liquid surface. A floating marble can easily move across water surface due to the low friction, allowing for the transport of aqueous solutions with minimal energy input. However, the motion of a floating marble has yet to be systematically characterised due to the lack of insight into key parameters such as the coefficient of friction between the floating marble and the carrier liquid. We measured the coefficient of friction of a small floating marble using a novel experimental setup that exploits the non-wetting properties of a liquid marble. A floating liquid marble pair containing a minute amount magnetite particles were immobilised and then released in a controlled manner using permanent magnets. The capillarity-driven motion was analysed to determine the coefficient of friction of the liquid marbles. The "capillary charge" model was used to fit the experimental results. We varied the marble content and carrier liquid to establish a relationship between the friction correction factor and the meniscus angle.

  5. CLINICAL OUTCOME AFTER OPERATIVE TREATMENT IN FLOATING SHOULDER- A PROSPECTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Nabarun Saha

    2017-06-01

    Full Text Available BACKGROUND The ‘floating shoulder’ is a rare injury consisting of ipsilateral fractures of the clavicle and glenoid neck. Although it may appear to be bony injury, studies suggest that ligamentous disruption associated with ipsilateral clavicle fracture and scapular neck fracture contributes to such entity. More commonly floating shoulder is defined as double disruption of the superior shoulder suspensory complex. Open reduction and internal fixation of both the fractures is the treatment of choice. We have made this study to assess clinical outcome after operative treatment of floating shoulder by DASH score. MATERIALS AND METHODS This is a study of 10 cases of floating shoulder injury operated in the same sitting by anterior approach for fracture clavicle and Judet’s posterior approach for scapula fracture from Jan 2014 to Oct 2016. All cases were assessed with DASH score at the end of six months. RESULTS Results of our study shows that majority of patients had excellent to good results with improvement in DASH score from 92.8 to 16.8 at final follow up. No major complications. All patients had radiological signs of union at the end of 1 year. CONCLUSION Surgical intervention should be considered for all floating shoulder injuries. open reduction and internal fixation not only increases stability but also to improves functional outcome of the patient. DASH score is an effective method to assess clinicofunctional outcome in post-operative cases of floating shoulder.

  6. Floating full-color image with computer-generated alcove rainbow hologram

    Science.gov (United States)

    Yamaguchi, Takeshi; Yoshikawa, Hiroshi

    2014-02-01

    We have investigated the floating full color image display with the computer-generated hologram (CGH). The floating image, when utilized as a 3D display, gives strong impression to the viewer. In our previous study, to change the CGH shape from the flat type to the half cylindrical type, the floating image from the output CGH has the nearly 180 degrees viewing angle. However, since the previous CGH does not have wavelength-selectivity, reconstructed image only has a single color. Also, the huge calculation amount of the fringe pattern is big problem. Therefore, we now propose the rainbow-type computer generated alcove hologram. To decrease the calculation amount, the rainbow hologram sacrifices the vertical parallax. Also, this hologram can reconstruct an image with white light. Compared with the previous study of the Fresnel type, the calculation speed becomes 165 times faster. After calculation, we print this hologram with a fringe printer, and evaluate reconstructed floating full color images. In this study, we introduce the computer-generated rainbow hologram into the floating image display. The rainbow hologram can reconstruct full color image with white light illumination. It can be recorded by using a horizontal slit to limit the vertical parallax. Therefore, the slit changes into the half cylindrical slit, the wide viewing angle floating image display can reconstruct full color image.

  7. Modeling the Fate and Distribution of Floating Litter Particles in the Aegean Sea (E. Mediterranean

    Directory of Open Access Journals (Sweden)

    Dimitrios V. Politikos

    2017-06-01

    Full Text Available A circulation model is coupled to a Lagrangian particle-tracking model to simulate the transport floating litter particles in the Aegean Sea, Greece (Eastern Mediterranean. Considering different source regions and release dates, simulations were carried out to explore the fate and distribution of floating litter over 1990–2009, taking into account the seasonal and interannual variability of surface circulation. Model results depicted recurrently high concentrations of floating litter particles in the North Aegean plateau, the Saronikos Gulf, and along Evia and Crete islands. Modeled transport pathways of floating litter demonstrated that source regions are interconnected, with Saronikos Gulf being a main receptor of litter from other sources. Notably higher percent of litter exit (~35% than enter the model domain (~7% signified that Aegean Sea seems to act as a source rather than receptor of floating litter pollution in the Eastern Mediterranean Sea. Beached litter was found around 10%, mostly located in the western part of the Aegean Sea. This is the first modeling study to explore the transport of floating marine litter in Greek waters.

  8. Lagrangian current measurements and large-scale long-term dispersion rates (Sofar float experiment)

    International Nuclear Information System (INIS)

    Gurbutt, F.A.

    1984-01-01

    Activity entering the water from a deep-sea disposal of radioactive waste package will be dispersed through the ocean both by the long-term circulation pattern and the eddy (mixing) motions. Sofar floats are thought to be the most cost-effective way of obtaining direct information on the circulation over a few years and the only way to obtain information, in the Lagrangian framework, on the statistics of the eddy movements. The Sofar float experiment seeks to answer questions including: (a) What is the magnitude of space and time variability of the horizontal eddy kinetic energy in the eastern bassin and is it consistent with that found in the western basin of the North Atlantic. (b) Is the deep flow inferred from incoherent arrays of moored current meters correct. The report covers the preparation stage for the Sofar float experiment whick takes place from autumn 1984 to 1986. It describes the recent results from the western North Atlantic, the design of the new deep Sofar float, the testing of the float including the range at which these new floats can be heard, the experimental design and expected results

  9. Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis.

    Science.gov (United States)

    Nojima, Daisuke; Ishizuka, Yuki; Muto, Masaki; Ujiro, Asuka; Kodama, Fumito; Yoshino, Tomoko; Maeda, Yoshiaki; Matsunaga, Tadashi; Tanaka, Tsuyoshi

    2017-05-27

    Water surface-floating microalgae have great potential for biofuel applications due to the ease of the harvesting process, which is one of the most problematic steps in conventional microalgal biofuel production. We have collected promising water surface-floating microalgae and characterized their capacity for biomass and lipid production. In this study, we performed chemical mutagenesis of two water surface-floating microalgae to elevate productivity. Floating microalgal strains AVFF007 and FFG039 (tentatively identified as Botryosphaerella sp. and Chlorococcum sp., respectively) were exposed to ethyl methane sulfonate (EMS) or 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), and pale green mutants (PMs) were obtained. The most promising FFG039 PM formed robust biofilms on the surface of the culture medium, similar to those formed by wild type strains, and it exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type. This study indicates that the chemical mutation strategy improves the lipid productivity of water surface-floating microalgae without inhibiting biofilm formation and floating ability.

  10. Enhanced Bioavailability and Dissolution of Atorvastatin Calcium from Floating Microcapsules using Minimum Additives.

    Science.gov (United States)

    Khan, Furquan Nazimuddin; Dehghan, Mohamed Hassan G

    2012-01-01

    Atorvastatin calcium, a lipid-lowering drug, is much less bioavailable because of reduced solubility in acidic media. Multiple-unit floating microcapsules of Atorvastatin calcium (ATC) were developed to expand the gastric residence time of the drug, as ATC has maximum rate of absorption in the upper GI tract. Floating microcapsules were prepared by Emulsion-solvent evaporation technique through incorporation of dioctyl sodium sulphosuccinate (DSS) as a dissolution enhancer. The microcapsules were assessed for shape, size, drug entrapment efficiency, stability and in-vitro drug dissolution rate and were subjected to SEM, DSC and PXRD studies. The ATC-loaded floating microcapsules were spherical in shape and had the particle size of about 28.10 μm and drug-loading efficiency of about 96.55 %. The floating microspheres containing DSS had significantly higher drug dissolution rates than those without DSS. The best formulation, AT4, consisting of Ethyl cellulose, DSS and Poly Ox®, had a maximum drug dissolution rate of 97.86 %, as compared to Storvas 80 mg (Ranbaxy Ltd, as a reference) which had a rate of only 54% during a period of 12 h in acidic media. A pharmacokinetic study performed on albino rabbits illustrates that the bioavailability of AT4 floating microcapsules significantly increased to nearly 1.7 times that of Storvas 80 mg. The present study indicates that the use of multi-unit floating microcapsules for delivery of ATC can improve its bioavailability.

  11. Lipid Profile

    Science.gov (United States)

    ... Known As Coronary Risk Panel Formal Name Lipid Profile This article was last reviewed on June 29, ... phospholipid molecules. The particles measured with a lipid profile are classified by their density into high-density ...

  12. Data Profiling

    OpenAIRE

    Hladíková, Radka

    2010-01-01

    Title: Data Profiling Author: Radka Hladíková Department: Department of Software Engineering Supervisor: Ing. Vladimír Kyjonka Supervisor's e-mail address: Abstract: This thesis puts mind on problems with data quality and data profiling. This Work analyses and summarizes problems of data quality, data defects, process of data quality, data quality assessment and data profiling. The main topic is data profiling as a process of researching data available in existing...

  13. Karolinske psychodynamic profile (KAPP)

    DEFF Research Database (Denmark)

    Mathiesen, Birgit Bork; Søgaard, Ulf

    2006-01-01

    psykologiske testmetoder, assesment, Karolinska psychodynamic profile (KAPP), psykodynamisk profil......psykologiske testmetoder, assesment, Karolinska psychodynamic profile (KAPP), psykodynamisk profil...

  14. Feasible pickup from intact ossicular chain with floating piezoelectric microphone

    Directory of Open Access Journals (Sweden)

    Kang Hou-Yong

    2012-02-01

    Full Text Available Abstract Objectives Many microphones have been developed to meet with the implantable requirement of totally implantable cochlear implant (TICI. However, a biocompatible one without destroying the intactness of the ossicular chain still remains under investigation. Such an implantable floating piezoelectric microphone (FPM has been manufactured and shows an efficient electroacoustic performance in vitro test at our lab. We examined whether it pick up sensitively from the intact ossicular chain and postulated whether it be an optimal implantable one. Methods Animal controlled experiment: five adult cats (eight ears were sacrificed as the model to test the electroacoustic performance of the FPM. Three groups were studied: (1 the experiment group (on malleus: the FPM glued onto the handle of the malleus of the intact ossicular chains; (2 negative control group (in vivo: the FPM only hung into the tympanic cavity; (3 positive control group (Hy-M30: a HiFi commercial microphone placed close to the site of the experiment ear. The testing speaker played pure tones orderly ranged from 0.25 to 8.0 kHz. The FPM inside the ear and the HiFi microphone simultaneously picked up acoustic vibration which recorded as .wav files to analyze. Results The FPM transformed acoustic vibration sensitively and flatly as did the in vitro test across the frequencies above 2.0 kHz, whereas inefficiently below 1.0 kHz for its overloading mass. Although the HiFi microphone presented more efficiently than the FPM did, there was no significant difference at 3.0 kHz and 8.0 kHz. Conclusions It is feasible to develop such an implantable FPM for future TICIs and TIHAs system on condition that the improvement of Micro Electromechanical System and piezoelectric ceramic material technology would be applied to reduce its weight and minimize its size.

  15. Floating Algae Blooms in the East China Sea

    Science.gov (United States)

    Qi, Lin; Hu, Chuanmin; Wang, Mengqiu; Shang, Shaoling; Wilson, Cara

    2017-11-01

    A floating algae bloom in the East China Sea was observed in Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in May 2017. Using satellite imagery from MODIS, Visible Infrared Imaging Radiometer Suite, Geostationary Ocean Color Imager, and Ocean Land Imager, and combined with numerical particle tracing experiments and laboratory experiments, we examined the history of this bloom as well as similar blooms in previous years and attempted to trace the bloom source and identify the algae type. Results suggest that one bloom origin is offshore Zhejiang coast where algae slicks have appeared in satellite imagery almost every February-March since 2012. Following the Kuroshio Current and Taiwan Warm Current, these "initial" algae slicks are first transported to the northeast to reach South Korea (Jeju Island) and Japan coastal waters (up to 135°E) by early April 2017, and then transported to the northwest to enter the Yellow Sea by the end of April. The transport pathway covers an area known to be rich in Sargassum horneri, and spectral analysis suggests that most of the algae slicks may contain large amount of S. horneri. The bloom covers a water area of 160,000 km2 with pure algae coverage of 530 km2, which exceeds the size of most Ulva blooms that occur every May-July in the Yellow Sea. While blooms of smaller size also occurred in previous years and especially in 2015, the 2017 bloom is hypothesized to be a result of record-high water temperature, increased light availability, and continuous expansion of Porphyra aquaculture along the East China Sea coast.

  16. Investigating the potential of floating mires as record of palaeoenvironmental changes

    Science.gov (United States)

    Zaccone, C.; Adamo, P.; Giordano, S.; Miano, T. M.

    2012-04-01

    Peat-forming floating mires could provide an exceptional resource for palaeoenvironmental and environmental monitoring studies, as much of their own history, as well as the history of their surrounds, is recorded in their peat deposits. In his Naturalis historia (AD 77-79), Pliny the Elder described floating islands on Lake Vadimonis (now Posta Fibreno Lake, Italy). Actually, a small floating island (ca. 35 m of diameter and 3 m of submerged thickness) still occurs on this calcareous lake fed by karstic springs at the base of the Apennine Mountains. Here the southernmost Italian populations of Sphagnum palustre occur on the small surface of this floating mire known as "La Rota", i.e., a cup-formed core of Sphagnum peat and rhizomes of Helophytes, erratically floating on the water-body of a submerged doline, annexed to the easternmost edge of the lake, characterised by the extension of a large reed bed. Geological evidence point out the existence in the area of a large lacustrine basin since Late Pleistocene. The progressive filling of the lake caused by changing in climatic conditions and neotectonic events, brought about the formation of peat deposits in the area, following different depositional cycles in a swampy environment. Then, a round-shaped portion of fen, originated around lake margins in waterlogged areas, was somehow isolated from the bank and started to float. Coupling data about concentrations and fluxes of several major and trace elements of different origin (i.e., dust particles, volcanic emissions, cosmogenic dusts and marine aerosols), with climate records (plant micro- and macrofossils, pollens, isotopic ratios), biomolecular records (e.g., lipids), detailed age-depth modelling (i.e., 210Pb, 137Cs, 14C), and humification indexes, the present work is hoped to identify and better understand the reliability of this particular "archive", and thus possible relationships between biogeochemical processes occurring in this floating bog and environmental

  17. Development and evaluation of a monolithic floating drug delivery system for acyclovir.

    Science.gov (United States)

    Tavakoli, Naser; Varshosaz, Jaleh; Dorkoosh, Farid; Motaghi, Sedigheh; Tamaddon, Lana

    2012-01-01

    Acyclovir (ACV), a model drug for this study, is one of the most effective drugs against viruses of the herpes group. Absorption of orally administered ACV is variable and incomplete, with a bioavailability of ca. 15-30%. The drug is absorbed in the duodenum after oral administration and hence, preparation of a floating drug delivery system (FDDS) for ACV may increase oral absorption of the drug. ACV matrix tablets (200 mg) containing an effervescent base (sodium bicarbonate and citric acid) and a binary combination of hydroxypropyl methylcellulose (HPMC) K4M with carbopol or sodium carboxymethyl cellulose (Na CMC) or polyvinylpyrrolidone (PVP) and/or sodium alginate were prepared by the direct compression method. The tablets were evaluated for physicochemical properties and in vitro floating ability (floating lag-time and duration), bioadhesiveness and drug release. The drug release studies were carried out in 0.1 N HCl (pH 1.2) at 37±0.5°C. At appropriate time intervals, samples were withdrawn and assayed spectrophotometrically at λ(max)=259 nm. The floating test showed tablets containing 15% effervescent base had a floating lag time of 10-30 s and a duration of floating time of 24 h. The formulations containing HPMC-PVP, HPMC-Na CMC, HPMC-carbopol, and HPMC-sodium alginate released about 60-90% of their drug content during a 12-h period. Increasing carbopol caused slower drug release. We concluded that the proposed tablets with 15% effervescent base, 20-30% HPMC, 30% Na CMC (and/or 20% PVP or 20% sodium alginate) showed good floating and drug release properties in vitro, and should be considered as FDDS for ACV.

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

    Science.gov (United States)

    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

  19. Optimal trajectory planning of free-floating space manipulator using differential evolution algorithm

    Science.gov (United States)

    Wang, Mingming; Luo, Jianjun; Fang, Jing; Yuan, Jianping

    2018-03-01

    The existence of the path dependent dynamic singularities limits the volume of available workspace of free-floating space robot and induces enormous joint velocities when such singularities are met. In order to overcome this demerit, this paper presents an optimal joint trajectory planning method using forward kinematics equations of free-floating space robot, while joint motion laws are delineated with application of the concept of reaction null-space. Bézier curve, in conjunction with the null-space column vectors, are applied to describe the joint trajectories. Considering the forward kinematics equations of the free-floating space robot, the trajectory planning issue is consequently transferred to an optimization issue while the control points to construct the Bézier curve are the design variables. A constrained differential evolution (DE) scheme with premature handling strategy is implemented to find the optimal solution of the design variables while specific objectives and imposed constraints are satisfied. Differ from traditional methods, we synthesize null-space and specialized curve to provide a novel viewpoint for trajectory planning of free-floating space robot. Simulation results are presented for trajectory planning of 7 degree-of-freedom (DOF) kinematically redundant manipulator mounted on a free-floating spacecraft and demonstrate the feasibility and effectiveness of the proposed method.

  20. Feasibility study on floating nuclear power plant (2). Safety design study of FNPP. Contract research

    International Nuclear Information System (INIS)

    Yabuuchi, Noriaki; Shimazaki, Junya; Ochiai, Masaaki; Nakazawa, Toshio

    2001-02-01

    In the previous report of 'Conceptual Design Study of FNPP (Floating Nuclear Power Plant)', a design study on a concept for FNPP, which is sited off the sea coast on the open sea with water depth of 20m and it is moored on protected sea by the breakwater was conducted and the floating platform guarded by the breakwater was found to be stable enough to install the nuclear power plant from analysis simulating the movement of the platform due to sea wave or wind. In this report, studies on a basic safety design concept of the FNPP, setting natural phenomena for design condition, required safety functions and a review on dynamic analysis of the large floating structure are presented. The studies revealed that the stability of the floating platform is an essential issue for the FNPP soundness, and the design base natural phenomena such as S1 and S2-class storm including S1 and S2-class earthquake should be considered in evaluation of the stability of the floating platform, and it is one of key technical subjects how to set the magnitude of these storm in application of design evaluation on each FNPP case. (J.P.N.)

  1. a Design of the Driver Airbag Module with Floating Horn Assembly

    Science.gov (United States)

    Suh, Chang-Min; Lee, Young-Hoon; Suh, Duck-Young

    The driver airbag system is designed as a supplemental restraint system in addition to the seatbelt, and is designed to protect the driver's head and chest against severe injury by a device that is actuated in case of vehicle's fronted impact. Deployment of an airbag module with floating horn assembly is a highly dynamic process. The concept of driver airbag module with floating horn assembly and aluminum emblem is presented as a useful parameter when the airbag deploys and the energy is evaluated as performance factor in airbag module. Floating horn assembly is also one of the major factors for driver airbag module design to perform its horn function and check the package between driver airbag module and steering wheel. This study on the design of driver airbag module with floating horn assembly proved the feasibility as a new safety device. However, the system level study is needed for decrease of passenger injury. This study can be used for the implementation of a prototype of DABM with floating horn device.

  2. 360 degree viewable floating autostereoscopic display using integral photography and multiple semitransparent mirrors.

    Science.gov (United States)

    Zhao, Dong; Su, Baiquan; Chen, Guowen; Liao, Hongen

    2015-04-20

    In this paper, we present a polyhedron-shaped floating autostereoscopic display viewable from 360 degrees using integral photography (IP) and multiple semitransparent mirrors. IP combined with polyhedron-shaped multiple semitransparent mirrors is used to achieve a 360 degree viewable floating three-dimensional (3D) autostereoscopic display, having the advantage of being able to be viewed by several observers from various viewpoints simultaneously. IP is adopted to generate a 3D autostereoscopic image with full parallax property. Multiple semitransparent mirrors reflect corresponding IP images, and the reflected IP images are situated around the center of the polyhedron-shaped display device for producing the floating display. The spatial reflected IP images reconstruct a floating autostereoscopic image viewable from 360 degrees. We manufactured two prototypes for producing such displays and performed two sets of experiments to evaluate the feasibility of the method described above. The results of our experiments showed that our approach can achieve a floating autostereoscopic display viewable from surrounding area. Moreover, it is shown the proposed method is feasible to facilitate the continuous viewpoint of a whole 360 degree display without flipping.

  3. Utilizing the Double-Precision Floating-Point Computing Power of GPUs for RSA Acceleration

    Directory of Open Access Journals (Sweden)

    Jiankuo Dong

    2017-01-01

    Full Text Available Asymmetric cryptographic algorithm (e.g., RSA and Elliptic Curve Cryptography implementations on Graphics Processing Units (GPUs have been researched for over a decade. The basic idea of most previous contributions is exploiting the highly parallel GPU architecture and porting the integer-based algorithms from general-purpose CPUs to GPUs, to offer high performance. However, the great potential cryptographic computing power of GPUs, especially by the more powerful floating-point instructions, has not been comprehensively investigated in fact. In this paper, we fully exploit the floating-point computing power of GPUs, by various designs, including the floating-point-based Montgomery multiplication/exponentiation algorithm and Chinese Remainder Theorem (CRT implementation in GPU. And for practical usage of the proposed algorithm, a new method is performed to convert the input/output between octet strings and floating-point numbers, fully utilizing GPUs and further promoting the overall performance by about 5%. The performance of RSA-2048/3072/4096 decryption on NVIDIA GeForce GTX TITAN reaches 42,211/12,151/5,790 operations per second, respectively, which achieves 13 times the performance of the previous fastest floating-point-based implementation (published in Eurocrypt 2009. The RSA-4096 decryption precedes the existing fastest integer-based result by 23%.

  4. Intelligent control for braking-induced longitudinal vibration responses of floating-type railway bridges

    International Nuclear Information System (INIS)

    Qu, Wei-Lian; Tu, Jian-Weia; Liu, Jia; Zhou, Qiang; Qin, Shun-Quan; Cheng, Haibin; Pi, Yong-Lin

    2009-01-01

    This paper presents an intelligent control method and its engineering application in the control of braking-induced longitudinal vibration of floating-type railway bridges. Equations of motion for the controlled floating-type railway bridges have been established based on the analysis of the longitudinal vibration responses of floating-type railway bridges to train braking and axle-loads of moving trains. For engineering applications of the developed theory, a full-scale 500 kN smart magnetorheologic (MR) damper has been designed, fabricated and used to carry out experiments on the intelligent control of braking-induced longitudinal vibration. The procedure for using the developed intelligent method in conjunction with the full-scale 500 kN MR dampers has been proposed and used to control the longitudinal vibration responses of the deck of floating-type railway bridges induced by train braking and axle-loads of moving trains. This procedure has been applied to the longitudinal vibration control of the Tian Xingzhou highway and railway cable-stayed bridge over the Yangtze River in China. The simulated results have shown that the intelligent control system using the smart MR dampers can effectively control the longitudinal response of the floating-type railway bridge under excitations of braking and axle-loads of moving trains

  5. Intelligent control for braking-induced longitudinal vibration responses of floating-type railway bridges

    Science.gov (United States)

    Qu, Wei-Lian; Qin, Shun-Quan; Tu, Jian-Weia; Liu, Jia; Zhou, Qiang; Cheng, Haibin; Pi, Yong-Lin

    2009-12-01

    This paper presents an intelligent control method and its engineering application in the control of braking-induced longitudinal vibration of floating-type railway bridges. Equations of motion for the controlled floating-type railway bridges have been established based on the analysis of the longitudinal vibration responses of floating-type railway bridges to train braking and axle-loads of moving trains. For engineering applications of the developed theory, a full-scale 500 kN smart magnetorheologic (MR) damper has been designed, fabricated and used to carry out experiments on the intelligent control of braking-induced longitudinal vibration. The procedure for using the developed intelligent method in conjunction with the full-scale 500 kN MR dampers has been proposed and used to control the longitudinal vibration responses of the deck of floating-type railway bridges induced by train braking and axle-loads of moving trains. This procedure has been applied to the longitudinal vibration control of the Tian Xingzhou highway and railway cable-stayed bridge over the Yangtze River in China. The simulated results have shown that the intelligent control system using the smart MR dampers can effectively control the longitudinal response of the floating-type railway bridge under excitations of braking and axle-loads of moving trains.

  6. Dynamic analysis of maritime gasbag-type floating bridge subjected to moving loads

    Directory of Open Access Journals (Sweden)

    Huan-huan Wang

    2016-03-01

    Full Text Available This paper studied the dynamic response of a new gasbag-type floating bridge under the effect of a moving load. The arbitrary Lagrangian-Eulerian (ALE method was used to simulate the movement of seawater and air, and the penalty-based method was used to study the coupling between gasbags and fluid. A three-dimensional finite element model of the floating bridge was established, and the numerical model was verified by comparing with the experimental results. In order to prevent resonance, the natural frequencies and flexural mode shapes were analyzed. Based on the initial state analysis, the dynamic responses of the floating bridge subjected to different moving loads were investigated. Vertical displacements and radial deformations of gasbags under different loads were compared, and principal stress distributions of gasbags were researched while driving. The hinge forces between adjacent modules were calculated to ensure the connection strength. Besides, the floating bridge under wave impacting was analyzed. Those results can provide references for the analysis and design of this new floating bridge.

  7. [Drinking behaviors and patterns among floating population aged 18-59 years old in China, 2012].

    Science.gov (United States)

    Li, Yichong; Zhang, Mei; Jiang, Yong; Deng, Qian; Zhao, Yinjun; Huang, Zhengjing; Zeng, Xinying; Wang, Limin

    2014-11-01

    To understand the drinking behaviors and patterns among floating population in China. Floating population were selected through multistage clustering sampling method, stratified by 6 major industries in 170 counties and districts from 31 provinces/autonomous regions, and Xinjiang Construction Corps, in mainland China. Design-based methods were adopted to analyze the drinking behavior in subpopulations. A total of 48 697 floating population aged 18-59 years were included in the study. The overall prevalence rate of drinking was 51.7% with 71.9% in men and 24.7% in women, in the last 12 months. Among those who ever drank, the weekly drinking prevalence and daily alcohol intake were 53.9% and 18.7 g in males while 16.7% and 4.1 g in females, respectively, among those floating population. Weekly drinking prevalence rates, for both genders, increased along with the increase of age (P population from the construction industry had the highest prevalence rates on items as weekly drinking, daily alcohol intake and prevalence of unhealthy drinking behaviors, except for hazardous drinking behaviors. Drinking behavior was prevalent among floating population in China. Significant difference was seen between genders. Unhealthy drinking behaviors varied greatly among male drinkers at different age groups or education levels as well as among those working in the different industries.

  8. Formulation of Gastric Floating System Using Bio-Sourced Terminalia Catappa Gum and in vivo Evaluation.

    Science.gov (United States)

    Meka, Venkata Srikanth; Murthy Kolapalli, Venkata Ramana

    2016-01-01

    A central composite design was applied to design a novel gastric floating drug delivery system comprising propranolol HCl in Terminalia catappa gum and to evaluate the buoyancy, in vitro drug release behavior, and pharmacokinetic parameters. All formulations exhibited good buoyancy properties in vitro reflected by floating lag time of 1-110 sec, total floating time of 9-16 h and prolonged release behaviour (upto 12 h). Statistically optimised formulation (PBGRso) was orally administered to human volunteers under both fasted and fed conditions to evaluate gastric floating behavior under different food conditions by X-ray evaluation. In vivo studies of optimised formulations revealed that the gastric residence time of floating tablets was enhanced in the fed but not in the fasted state. Pharmacokinetic studies of the optimised Terminalia catappa formulation and a commercial product (Ciplar LA 80) carried out on healthy human volunteers showed a significant improvement in the bioavailability (132%) of propranolol HCl released from from the experimental Terminalia catappa formulations compared with Ciplar LA 80.

  9. Photoinduced Recovery of Organic Transistor Memories with Photoactive Floating-Gate Interlayers.

    Science.gov (United States)

    Jeong, Yong Jin; Yun, Dong-Jin; Kim, Se Hyun; Jang, Jaeyoung; Park, Chan Eon

    2017-04-05

    Optical memories based on photoresponsive organic field-effect transistors (OFETs) are of great interest due to their unique applications, such as multibit storage memories and flexible imaging circuits. Most studies of OFET-type memories have focused on the photoresponsive active channels, but more useful functions can be additionally given to the devices by using floating gates that can absorb light. In this case, effects of photoirradiation on photoactive floating-gate layers need to be fully understood. Herein, we studied the photoinduced erasing effects of floating-gate interlayers on the electrical responses of OFET-type memories and considered the possible mechanisms. Polymer/C 60 composites were inserted between pentacene and SiO 2 to form photoresponsive floating-gate interlayers in transistor memory. When exposed to light, C 60 generated excitons, and these photoexcited carriers contributed to the elimination of trapped charge carriers, which resulted in the recovery of OFET performance. Such memory devices exhibited bistable current states controlled with voltage-driven programming and light-driven erasure. Furthermore, these devices maintained their charge-storing properties over 10 000 s. This proof-of-concept study is expected to open up new avenues in information technology for the development of organic memories that exhibit photoinduced recovery over a wide range of wavelengths of light when combined with appropriate photoactive floating-gate materials.

  10. Effect of Second-Order Hydrodynamics on Floating Offshore Wind Turbines: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Roald, L.; Jonkman, J.; Robertson, A,; Chokani, N.

    2013-07-01

    Offshore winds are generally stronger and more consistent than winds on land, making the offshore environment attractive for wind energy development. A large part of the offshore wind resource is however located in deep water, where floating turbines are the only economical way of harvesting the energy. The design of offshore floating wind turbines relies on the use of modeling tools that can simulate the entire coupled system behavior. At present, most of these tools include only first-order hydrodynamic theory. However, observations of supposed second-order hydrodynamic responses in wave-tank tests performed by the DeepCwind consortium suggest that second-order effects might be critical. In this paper, the methodology used by the oil and gas industry has been modified to apply to the analysis of floating wind turbines, and is used to assess the effect of second-order hydrodynamics on floating offshore wind turbines. The method relies on combined use of the frequency-domain tool WAMIT and the time-domain tool FAST. The proposed assessment method has been applied to two different floating wind concepts, a spar and a tension-leg-platform (TLP), both supporting the NREL 5-MW baseline wind turbine. Results showing the hydrodynamic forces and motion response for these systems are presented and analysed, and compared to aerodynamic effects.

  11. Modeling of 4H—SiC multi-floating-junction Schottky barrier diode

    International Nuclear Information System (INIS)

    Hong-Bin, Pu; Lin, Cao; Zhi-Ming, Chen; Jie, Ren; Ya-Gong, Nan

    2010-01-01

    This paper develops a new and easy to implement analytical model for the specific on-resistance and electric field distribution along the critical path for 4H—SiC multi-floating junction Schottky barrier diode. Considering the charge compensation effects by the multilayer of buried opposite doped regions, it improves the breakdown voltage a lot in comparison with conventional one with the same on-resistance. The forward resistance of the floating junction Schottky barrier diode consists of several components and the electric field can be understood with superposition concept, both are consistent with MEDICI simulation results. Moreover, device parameters are optimized and the analyses show that in comparison with one layer floating junction, multilayer of floating junction layer is an effective way to increase the device performance when specific resistance and the breakdown voltage are traded off. The results show that the specific resistance increases 3.2 mΩ·cm 2 and breakdown voltage increases 422 V with an additional floating junction for the given structure. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  12. Modelling and Simulation of Free Floating Pig for Different Pipeline Inclination Angles

    Directory of Open Access Journals (Sweden)

    Woldemichael Dereje Engida

    2016-01-01

    Full Text Available This paper presents a modelling and simulation of free floating pig to determine the flow parameters to avoid pig stalling in pigging operation. A free floating spherical shaped pig was design and equipped with necessary sensors to detect leak along the pipeline. The free floating pig does not have internal or external power supply to navigate through the pipeline. Instead, it is being driven by the flowing medium. In order to avoid stalling of the pig, it is essential to conduct simulation to determine the necessary flow parameters for different inclination angles. Accordingly, a pipeline section with inclination of 0°, 15°, 30°, 45°, 60°, 75°, and 90° were modelled and simulated using ANSYS FLUENT 15.0 with water and oil as working medium. For each case, the minimum velocity required to propel the free floating pig through the inclination were determined. In addition, the trajectory of the free floating pig has been visualized in the simulation.

  13. Wave response analyses of floating crane structure; Crane sen no jobu kozobutsu no haro oto

    Energy Technology Data Exchange (ETDEWEB)

    Nobukawa, H.; Takaki, M.; Kitamura, M.; Ahou, G. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering; Higashimura, M. [Fukada Salvage and Marine Works Co. Ltd., Osaka (Japan)

    1996-12-31

    Identifying a dynamic load acting on a lifted load in a floating crane moving in waves is important for preparing an operation manual for the floating crane. Analyses were made on motions in waves of a floating crane with a lifting load of 3,600 tons, with considerations given to deformation of the crane structure. Discussions were given on a dynamic load acting on a lifted load. If a case that considers elastic deformation in the crane structure is compared with a case that does not consider same in calculating hull motions of the floating crane, the difference between them is small if wave length {lambda} to the ship length L is about 0.5. However, if {lambda}/L is 1.0 and 1.5, the difference grows very large. Therefore, the effect of deformation in the crane structure on hull motions of the floating crane cannot be ignored in these cases. A dynamic load acting on a lifted load that considers deformation in the crane structure is about 5% of lifted weight in a headsea condition in which the wave height is 2 m and {lambda}/L is 1.5. As opposed, an estimated value of a dynamic load when the crane structure is regarded as a rigid body is 13%, which is 2.6 times as great as the case that considers deformation of the crane structure. 3 refs., 17 figs., 1 tab.

  14. Considerations over the floating speed of a particle in vacuum pneumatic conveying sytems in flour milling

    Directory of Open Access Journals (Sweden)

    Tanase Tanase

    2016-06-01

    Full Text Available The present paper is a theoretical study aiming for to assess the influence of the different factors such as deviation from the spherical form of a particle, specific mass load of the pneumatic conveying pipe and the report between the particle diameter and the pipe diameter, over the floating speed of a particle. For a non-spherical particle, the Magnus force is affecting the floating speed of the given particle by increasing or decreasing it. The equation deducted within the present study, describes the movement of a particle or a fluid swirl under the resultant force with emphasis on the evaluation of the nature and magnitude of the Magnus force. The same Magnus Force explains the movement of the swirls in fluids, as for the wind swirls (hurricane or water swirls. The next part of the study relate the report between the particle diameter and the pipe diameter as well as the specific loads of the pipe, to the same floating speed. A differentiation in denominating the floating speed is proposed as well as that for the non-spherical particle the floating speed should be a domain, rather than a single value.

  15. Microclimate and architectural tectonic: vernacular floating house resilience in Seberang Ulu 1, Palembang

    Science.gov (United States)

    Puspitasari, P.; Kadri, T.; Indartoyo, I.; Kusumawati, L.

    2018-01-01

    This paper aims to describe the results of preliminary research on floating houses on the Musi River, Seberang Ulu 1, Palembang, focused on studying the influence of microclimates to the tectonics of Rumah Rakit (Floating House). The increase of water surface due to global warming will increase the need of using floating house typology in the future. The description of the inhabitants’ experiences on applying technics to create vernacular floating houses is considered as significant knowledge to develop advance technology on the basis of local characteristic. Vernacular floating houses resilience consists of natural experiences of inhabitants in adapting their daily activities to the characteristic of local climate. By using qualitative approach, the Rumah Rakit inhabitants’ verbal information in this article becomes the main aspect in exploring local knowledge. At the end, the conceptual model of vernacular Rumah Rakit in Seberang Ulu 1, Palembang is formulated, in terms of building architectural tectonic that is closely related to the local climate characteristic. The knowledge can be utilized in the context of rehabilitation or preservation of such architectural objects that are their existences tend to be extinct at this time.

  16. Comparison growth of Kappaphycus alvarezii (Rhodophyta, Solieriaceae cultivation in floating cage and longline in Indonesia

    Directory of Open Access Journals (Sweden)

    Ma’ruf Kasim

    2017-05-01

    Full Text Available Currently, cultivation using cages for Kappaphycus alvarezii was limited reported before. This study aims to reveal growth of K. alvarezii cultivated in floating cages and longline. The study was conducted in one of cultivation areas in Southeast Sulawesi, Indonesia. Total gross weight, propagule growth rate and specific growth rate were performing in this study. During our field experiment, total gross weight of K. alvarezii after 40 days, from 5 kg was growth to 22.5 ± 1.40 kg and 38.8 ± 1.6 kg on longline and floating cages, respectively. Propagule growth rate after 40 days, from 50 g was 107.8 ± 7.0 g and 152.5 ± 7.9 g during April, and 132.0 ± 8.0 g and 218.8 ± 8.6 g during August, on longline and floating cage, respectively. Specific growth rate of K. alvarezii was high during August, 2.43% day−1 and 3.69% day−1 cultivated in longline and floating cage, respectively. Propagule morphology was white and damage in 40% cultivated by longline and no damage by using floating cage particular in August and September while high dense of herbivorous fish surrounding the experimental sites.

  17. Large capacity multi-float configurations for the wave energy converter M4 using a time-domain linear diffraction model

    OpenAIRE

    Stansby, Peter; Carpintero Moreno, Efrain; Stallard, Timothy

    2017-01-01

    The moored three-float line absorber WEC M4 has been developed to optimise power capture through experiments and linear diffraction modelling. With the progression down wave from small to medium to large floats, the device heads naturally into the wave direction. The bow and mid floats are rigidly connected by a beam and a beam from the stern float is connected to the hinge point above the mid float for power take off (PTO). Increasing the bow to mid float spacing to be more than 50% greater ...

  18. KAPEX RAFOS float data report 1997 - 1999. Pt. A. The Agulhas- and South Atlantic current components

    Energy Technology Data Exchange (ETDEWEB)

    Boebel, O.; Anderson-Fontana, S.; Lazarevich, P.; Prater, M.; Rossby, T. [Rhode Island Univ., Narragansett, RI (United States). Graduate School of Oceanography; Schmid, C.; Zenk, W. [Institut fuer Meereskunde an der Univ. Kiel (Germany); Ansorge, I.; Lutjeharms, J. [Cape Town Univ. (South Africa). Dept. of Oceanography

    2000-10-01

    This data report presents trajectories and corresponding in-situ data for all acoustically tracked RAFOS floats that were deployed within the Agulhas and the South Atlantic Current components of KAPEX. KAPEX stands for Cape of Good Hope Experiment, Kaap die Goeie Hoop Eksperimente or Kap der Guten Hoffnung Experiment in the three languages of the participating authors. The objective of the program was to study the interocean exchange of subsurface waters south of Africa between the Atlantic and the Indian Oceans. A total of 92 floats were deployed during four cruises at depths between 100 - 1200 m during March 1997 and June 1998. It is the first time that eddy-resolving floats are used to measure ocean flow patterns at intermediate and thermocline levels off southern Africa. (orig.)

  19. A Numerical Approach to Determine Attitude Dynamics of Floating Bodies with Irregular Configurations

    Directory of Open Access Journals (Sweden)

    Jiann-Lin Chen

    2014-07-01

    Full Text Available This study acquires the attitude dynamics of floating bodies with irregular configurations using an effective computational model, which has been validated theoretically and verified by experiments. By comparison a correlation formula was described to predict inclinations for the floating slender body imitating an excise torpedo. Thereafter a computational model was developed to account for bodies with attitudes in more general situations. For demonstration, a submersible was simulated to reveal that the inclinations vary abruptly around certain longitudinal locations of center of gravity. The property variations during water ingress assumption were presented. Similar to the virtue tank, an innovative concept of building the numerical data base for a specific floating body has been proposed, by which the position of its center of gravity can be obtained by interpolation from attitude data in tables as determined by the present computational model.

  20. Study on design method and vibration reduction characteristic of floating raft with periodic structure

    Science.gov (United States)

    Fang, Yuanyuan; Zuo, Yanyan; Xia, Zhaowang

    2018-03-01

    The noise level is getting higher with the development of high-power marine power plant. Mechanical noise is one of the most obvious noise sources which not only affect equipment reliability, riding comfort and working environment, but also enlarge underwater noise. The periodic truss type device which is commonly applied in fields of aerospace and architectural is introduced to floating raft construction in ship. Four different raft frame structure are designed in the paper. The vibration transmissibility is taken as an evaluation index to measure vibration isolation effect. A design scheme with the best vibration isolation effect is found by numerical method. Plate type and the optimized periodic truss type raft frame structure are processed to experimental verify vibration isolation effect of the structure of the periodic raft. The experimental results demonstrate that the same quality of the periodic truss floating raft has better isolation effect than that of the plate type floating raft.

  1. A methodology for determining and controlling the buffers before floating bottlenecks in heavy machinery production

    Directory of Open Access Journals (Sweden)

    R. Lenort

    2013-07-01

    Full Text Available Heavy machinery industry is characterized by a number of specific features that cause significant variations in the processing time of products in the individual workplaces and frequent occurrence of floating bottlenecks, which change their positions. Depending on the product range being processed, a given workplace is the bottleneck only for some period of time. When the bottleneck moves to another workplace, it leads to unnecessary loss of capacity of the floating bottleneck. To maximize the utilization, it is necessary to protect those bottlenecks by creating special buffers. The objective of this article is to design a methodology used for the determination and control of buffers that are going to protect the floating bottlenecks from operating capacity losses caused by transfer of the constrain to another workplace. These buffers are referred to as „power buffers“. The designed methodology has been verified in the process of forged pieces machining.

  2. Floating and sinking: the imprint of massive scalars around rotating black holes.

    Science.gov (United States)

    Cardoso, Vitor; Chakrabarti, Sayan; Pani, Paolo; Berti, Emanuele; Gualtieri, Leonardo

    2011-12-09

    We study the coupling of massive scalar fields to matter in orbit around rotating black holes. It is generally expected that orbiting bodies will lose energy in gravitational waves, slowly inspiraling into the black hole. Instead, we show that the coupling of the field to matter leads to a surprising effect: because of superradiance, matter can hover into "floating orbits" for which the net gravitational energy loss at infinity is entirely provided by the black hole's rotational energy. Orbiting bodies remain floating until they extract sufficient angular momentum from the black hole, or until perturbations or nonlinear effects disrupt the orbit. For slowly rotating and nonrotating black holes floating orbits are unlikely to exist, but resonances at orbital frequencies corresponding to quasibound states of the scalar field can speed up the inspiral, so that the orbiting body sinks. These effects could be a smoking gun of deviations from general relativity.

  3. Catamaran or semi-submersible for floating platform – selection of a better design

    Science.gov (United States)

    Qasim, Idrees; Gao, Liangtian; Peng, Duojin; Liu, Bo

    2018-02-01

    With nonstop advancement in marine engineering, more and more new structures are being designed and explored for tidal current energy. There are three different kinds of support structures for tidal current power station mostly in use, which are sea-bed mounted/gravity based system, pile mounted system and floating moored platform. Comparing all of them, the floating mooring system is most suitable for deep water systems and the application of this arrangement is widely usable. In this paper, a semi-submersible and a catamaran as floating platforms for tidal current power stations are studied are compared on the basis of its economics, efficiency of turbine and stability of the station. Based on basic ship theory and using software MAXSURF, the stability of Catamaran tidal current power station is also calculated. It is found that the catamaran design is optimal choice.

  4. Ultra Low Voltage Class AB Switched Current Memory Cells Based on Floating Gate Transistors

    DEFF Research Database (Denmark)

    Mucha, Igor

    1999-01-01

    A proposal for a class AB switched current memory cell, suitable for ultra-low-voltage applications is presented. The proposal employs transistors with floating gates, allowing to build analog building blocks for ultralow supply voltage operation also in CMOS processes with high threshold voltages....... This paper presents the theoretical basis for the design of "floating-gate'' switched current memory cells by giving a detailed description and analysis of the most important impacts degrading the performance of the cells. To support the theoretical assumptions circuits based on "floating-gate'' switched...... current memory cells were designed using a CMOS process with threshold voltages V-T0n = \\V-T0p\\ = 0.9 V for the n- and p-channel devices. Both hand calculations and PSPICE simulations showed that the designed example switched current memory cell allowed a maximum signal range better than +/-18 mu...

  5. Formulation and in vitro characterization of ciprofloxacin floating and bioadhesive extended-release tablets.

    Science.gov (United States)

    Varshosaz, Jaleh; Tavakoli, N; Roozbahani, F

    2006-01-01

    Ciprofloxacin is mainly absorbed in the proximal areas of the gastrointestinal tract. The purpose of our study was production of floating-bioadhesive tablets to lengthen the stay of drug in its absorption area. Effervescent tablets were made using sodium carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose (HPMC), polyacrylic acid (AA), polymetacrylic acid (MAA), citric acid, and sodium bicarbonate. Tablets with 5% effervescent base had longer lag time than 10%. The type of polymer had no significant effect on the floating lag time. All tablets floated atop the medium for 23-24 hr. Increasing CMC caused higher mucoadhesion than AA (p < 0.05). All formulations showed a Higuchi, non-Fickian release mechanism. Tablets with 10% effervescent base, 80% CMC/20% HPMC, or 80% AA /20% MAA seemed desirable.

  6. A novel floating simulation topology composed of only grounded passive components

    Science.gov (United States)

    Yuce, Erkan

    2010-03-01

    In this article, a novel simulator circuit using two differential voltage current conveyors (DVCCs) and three grounded passive components is suggested. Depending on the passive component selection, the developed topology can realise synthetic floating inductors, floating capacitors and floating frequency dependent negative resistors. It does not suffer from passive component matching constraints. As an application example of the proposed simulation circuit, a voltage-mode multifunction filter for simultaneously providing low-pass, band-pass, high-pass and notch responses from the same structure is given. The suggested filter example is composed of only grounded passive components without requiring critical matching conditions, which is suitable for integration. Further, signal limitations of the simulator circuits are discussed. In order to show the performance of the introduced circuit and verify the claimed ideas, we perform simulations using SPICE.

  7. A Flexible VHDL Floating Point Module for Control Algorithm Implementation in Space Applications

    Science.gov (United States)

    Padierna, A.; Nicoleau, C.; Sanchez, J.; Hidalgo, I.; Elvira, S.

    2012-08-01

    The implementation of control loops for space applications is an area with great potential. However, the characteristics of this kind of systems, such as its wide dynamic range of numeric values, make inadequate the use of fixed-point algorithms.However, because the generic chips available for the treatment of floating point data are, in general, not qualified to operate in space environments and the possibility of using an IP module in a FPGA/ASIC qualified for space is not viable due to the low amount of logic cells available for these type of devices, it is necessary to find a viable alternative.For these reasons, in this paper a VHDL Floating Point Module is presented. This proposal allows the design and execution of floating point algorithms with acceptable occupancy to be implemented in FPGAs/ASICs qualified for space environments.

  8. Description of signature scales in a floating wind turbine model wake subjected to varying turbulence intensity

    Science.gov (United States)

    Kadum, Hawwa; Rockel, Stanislav; Holling, Michael; Peinke, Joachim; Cal, Raul Bayon

    2017-11-01

    The wake behind a floating model horizontal axis wind turbine during pitch motion is investigated and compared to a fixed wind turbine wake. An experiment is conducted in an acoustic wind tunnel where hot-wire data are acquired at five downstream locations. At each downstream location, a rake of 16 hot-wires was used with placement of the probes increasing radially in the vertical, horizontal, and diagonally at 45 deg. In addition, the effect of turbulence intensity on the floating wake is examined by subjecting the wind turbine to different inflow conditions controlled through three settings in the wind tunnel grid, a passive and two active protocols, thus varying in intensity. The wakes are inspected by statistics of the point measurements, where the various length/time scales are considered. The wake characteristics for a floating wind turbine are compared to a fixed turbine, and uncovering its features; relevant as the demand for exploiting deep waters in wind energy is increasing.

  9. Floating nuclear power station of APWS-80 type for electricity generation and fresh water production

    International Nuclear Information System (INIS)

    Zverev, K.V.; Polunichev, V.I.; Sergeev, Yu.A.

    1997-01-01

    To solve the problem of seawater desalination and electric energy generation, the designing organizations of Russia have developed two variants of floating nuclear desalination plant. The KLT-40 type reactors, with maximum 160 MW thermal power, is used as the power source for such plant. Depending on the customer requirement one or two power unit could be installed in the floating desalination plant. There are APWS-80 with two reactors, producing 80,000 m 3 desalinated water per day and APWS-40 with one reactor, producing 40,000 m 3 desalinated water per day. The advantages of floating desalination plants are the possibility to build and test them at the ship-build plant of the supplier country and to hand them over on turnkey base. (author). 5 figs

  10. High chrome exhaustion in a non-float tanning process using a sulphonic aromatic acid.

    Science.gov (United States)

    Bacardit, Anna; Morera, Josep M; Ollé, Lluís; Bartolí, Esther; Dolors Borràs, M

    2008-10-01

    Tanning processes performed in drums consume large amounts of water and chemicals, most of which end up in the wastewater. This study explores an alternative approach at an industrial scale to the traditional pickle-chrome tanning method. The new method replaces formic and sulphuric acids with sulphonic aromatic acid. Because it is done without float, there is a sizeable reduction in the amount of added salt and chrome salt as well as an increase in temperatures at the end of the tanning process. From an environmental perspective, the new method offers important advantages. For instance, there is no float addition in the tannage. Also, there are reductions of 94% and 99%, respectively, in the discharge of chlorides and chrome, as well as a 75% reduction in the residual float. Our financial assessment demonstrated that the new method is 42% cheaper than a traditional approach.

  11. Grid Simulator for Testing a Wind Turbine on Offshore Floating Platform

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, V.

    2012-02-01

    An important aspect of such offshore testing of a wind turbine floating platform is electrical loading of the wind turbine generator. An option of interconnecting the floating wind turbine with the onshore grid via submarine power cable is limited by many factors such as costs and associated environmental aspects (i.e., an expensive and lengthy sea floor study is needed for cable routing, burial, etc). It appears to be a more cost effective solution to implement a standalone grid simulator on a floating platform itself for electrical loading of the test wind turbine. Such a grid simulator must create a stable fault-resilient voltage and frequency bus (a micro grid) for continuous operation of the test wind turbine. In this report, several electrical topologies for an offshore grid simulator were analyzed and modeled.

  12. Conceptual Design of a Floating Support Structure and Mooring System for a Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Berthelsen, Petter Andreas; Fylling, Ivar; Vita, Luca

    2012-01-01

    This paper deals with the conceptual design of a floating support structure and mooring system for a 5MW vertical axis offshore wind turbine. The work is carried out as part of the DeepWind project, where the main objective is to investigate the feasibility of a floating vertical axis offshore wind...... turbine. The DeepWind concept consists of a Darrieus rotor mounted on a spar buoy support structure. The conceptual design is carried out in an iterative process, involving the different subcomponents. The present work is part of the first design iteration and the objective is to find a feasible floating...... support structure and mooring system for the DeepWind concept. The conceptual design is formulated as an optimization problem: Starting with an initial configuration, the optimization procedure tries to find a cheaper solution while satisfying a set of design requirements. This approach utilizes available...

  13. Generating and executing programs for a floating point single instruction multiple data instruction set architecture

    Science.gov (United States)

    Gschwind, Michael K

    2013-04-16

    Mechanisms for generating and executing programs for a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA) are provided. A computer program product comprising a computer recordable medium having a computer readable program recorded thereon is provided. The computer readable program, when executed on a computing device, causes the computing device to receive one or more instructions and execute the one or more instructions using logic in an execution unit of the computing device. The logic implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA), based on data stored in a vector register file of the computing device. The vector register file is configured to store both scalar and floating point values as vectors having a plurality of vector elements.

  14. Discovery of a Free-Floating Double Planet?

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    An object previously identified as a free-floating, large Jupiter analogturns out to be two objects each with the mass of a few Jupiters. This system is the lowest-mass binary weve ever discovered.Tracking Down Ages2MASS J111932541137466 is thought to be a member of the TW Hydrae Association, a group of roughly two dozen young stars moving together in the solar neighborhood. [University of Western Ontario/Carnegie Institution of Washington DTM/David Rodriguez]Brown dwarfs represent the bottom end of the stellar mass spectrum, with masses too low to fuse hydrogen (typically below 75-80 Jupiter masses). Observing these objects provides us a unique opportunity to learn about stellar evolution and atmospheric models but to properly understand these observations, we need to determine the dwarfs masses and ages.This is surprisingly difficult, however. Brown dwarfs cool continuously as they age, which creates an observational degeneracy: dwarfs of different masses and ages can have the same luminosity, making it difficult to infer their physical properties from observations.We can solve this problem with an independent measurement of the dwarfs masses. One approach is to find brown dwarfs that are members of nearby stellar associations called moving groups. The stars within the association share the same approximate age, so a brown dwarfs age can be estimated based on the easier-to-identify ages of other stars in the group.An Unusual BinaryRecently, a team of scientists led by William Best (Institute for Astronomy, University of Hawaii) were following up on such an object: the extremely red, low-gravity L7 dwarf 2MASS J111932541137466, possibly a member of the TW Hydrae Association. With the help of the powerful adaptive optics on the Keck II telescope in Hawaii, however, the team discovered that this Jupiter-like objectwas hiding something: its actually two objects of equal flux orbiting each other.Keck images of 2MASS J111932541137466 reveal that this object is actually

  15. Analysis of Heavy Metal Content (Pb) on Waters and Fish at The Floating Cages BPPP Ambon

    Science.gov (United States)

    Wattimena, Rachel L.; Selanno, Debby A. J.; Tuhumury, Semuel F.; Tuahatu, Juliana W.

    2018-02-01

    Coastal waters play important roles due to highly in natural resources and developing of environmental services. However, there are highly intensity of natural resources utilization, environment and settlement. Consequently, environment and natural resources would be degraded such as in the Ambon Bay. One of the potency at the Ambon Bay is mariculture area namely the floating cages (KJA) which belongs to Fisheries education and training (BPPP) Ambon. The research aimed to analyze physical-chemical of waters (temperature, pH, salinity and current speed), to analyze heavy metal concentration (Pb) on water and fish from floating cages (KJA) and to analyze waters pollution status at KJA BPPP Ambon. The average salinity of each floating cage ranged from 30.09 - 30.34°C, pH ranged from 8.03 - 8.44, salinity ranged from 31.36 - 33.34 PSU, and current speed at spring tide ranged from 0.5 - 55.8 Cm/sec while neap tide ranged from 0.1 - 9.8 Cm/sec. Heavy metal concentration (Pb) on waters was below the standard for waters quality and the average concentration was 0.002 mg/l. Whilst, the heavy metal concentration (Pb) on fishes was below standard for floating cages (floating cages 2-6) which was 0.05 and 0.17mg/l. Otherwise, floating cage 1 had been above maximum standard for fish food and its processing following SNI 7387:2009 (0.3mg/l) which was 0.31 mg/l. The status of waters pollution at KJA BPPP Ambon belonged to C class and could be categorized as moderate based on standard for waters quality issued by State Ministerial Decree for the Environment No. 51 Year 2004.

  16. RESEARCH OF USING OPEN DOUBLE T BEAMS FOR SPANS IN FLOATING BRIDGES

    Directory of Open Access Journals (Sweden)

    YU. M. Gorbatiuk

    2014-03-01

    Full Text Available Purpose. The publication presents the results of calculations of spans for floating bridges with open double T beams. The purpose of research is to analyze the suitability of spans from open double T beams for floating bridges with minimum weight under loads, which is provided by standards for modern floating bridges designing. Methodology. Comparative method, analytical calculation methods (influence lines methodology, strength calculations, endurance, maximum shear stress are used in this paper. Findings. Current loads for bridges calculations are 75% more than those, for which the spans of floating bridge from NZhM-56 property are designed. The use of open double T beams that is formed with double T beam no. 70 (the height of the open one is 104 cm reduces the cross sectional area in a weakened spot, but virtually it does not influence the strength and durability of the material. The use of open double T beams for spans of floating bridges saves up to 22 % of metal that means one in five spans will made of saved metal. Savings on each spans, such as CRP, will be 33.6 - 263 thous. grn. (considering the price of 1 ton of final product 29 thous. grn.. Originality. Research allows making next step in material saving and use of open double T beams for spans in the whole. Practical value. The obtained results give us possibility to make a number of conclusions that allow us to become more familiar and more practical with the use of open double T beams for spans of floating bridges.

  17. Active structural control of a floating wind turbine with a stroke-limited hybrid mass damper

    Science.gov (United States)

    Hu, Yaqi; He, Erming

    2017-12-01

    Floating wind turbines are subjected to more severe structural loads than fixed-bottom wind turbines due to additional degrees of freedom (DOFs) of their floating foundations. It's a promising way of using active structural control method to improve the structural responses of floating wind turbines. This paper investigates an active vibration control strategy for a barge-type floating wind turbine by setting a stroke-limited hybrid mass damper (HMD) in the turbine's nacelle. Firstly, a contact nonlinear modeling method for the floating wind turbine with clearance between the HMD and the stroke limiters is presented based on Euler-Lagrange's equations and an active control model of the whole system is established. The structural parameters are validated for the active control model and an equivalent load coefficient method is presented for identifying the wind and wave disturbances. Then, a state-feedback linear quadratic regulator (LQR) controller is designed to reduce vibration and loads of the wind turbine, and two optimization methods are combined to optimize the weighting coefficients when considering the stroke of the HMD and the active control power consumption as constraints. Finally, the designed controllers are implemented in high fidelity simulations under five typical wind and wave conditions. The results show that active HMD control strategy is shown to be achievable and the designed controllers could further reduce more vibration and loads of the wind turbine under the constraints of stroke limitation and power consumption. "V"-shaped distribution of the TMD suppression effect is inconsistent with the Weibull distribution in practical offshore floating wind farms, and the active HMD control could overcome this shortcoming of the passive TMD.

  18. Industrial waste - destination and valuation techniques of floating hoses: case study in Macaé, RJ

    Directory of Open Access Journals (Sweden)

    Marlon de Almeida Clemente Silva

    2017-10-01

    Full Text Available A large part of the oil extracted in Brazil today, is drained to the coast, or even transported to larger vessels through Floating Hoses. This oil unloading operation is called Offloading, it is of fundamental importance for the performance of offshore operations. These operating units use storage systems and oil relief, which can be FSO (Floating Storage Unit and Transfer or FPSO (Floating Production Unit, Stockpiling and Transfer. In this oil transshipment scenario, floating hoses have primary role therefore they are responsible for this operation. The Floating Hoses after useful life are discarded. How do the environmentally correct disposal of this waste? The destination most used for this waste are the landfills Class 2, for non-hazardous waste. In this study, we attempted to develop appropriate allocation techniques for Floating Hose, in order to obtain a greater appreciation potential of the materials that compose it, as well as presenting the risk of these being put up in a landfill, even if it is a controlled landfill. This technique is based on a so-called Reverse Manufacturing, all components are reused and recovered, with a more environmentally sound and economically viable destination. The research methodology was based on empirical studies of phenomenological framework, involving operational staff of a medium-sized company with a rising share of Treatment and Waste Disposal Market, in the city of Macaé. It was evidenced in the survey that there is a possibility of potential gains from the application of reverse manufacturing techniques of hoses, both in terms of environmental liability reductions and the financial return through the recovery of materials that compose them.

  19. Plant traits and environment: floating leaf blade production and turnover of waterlilies.

    Science.gov (United States)

    Klok, Peter F; van der Velde, Gerard

    2017-01-01

    Floating leaf blades of waterlilies fulfill several functions in wetland ecosystems by production, decomposition and turnover as well as exchange processes. Production and turnover rates of floating leaf blades of three waterlily species, Nuphar lutea (L.) Sm., Nymphaea alba L. and Nymphaea candida Presl, were studied in three freshwater bodies, differing in trophic status, pH and alkalinity. Length and percentages of leaf loss of marked leaf blades were measured weekly during the growing season. Area and biomass were calculated based on leaf length and were used to calculate the turnover rate of floating leaf blades. Seasonal changes in floating leaf production showed that values decreased in the order: Nymphaea alba , Nuphar lutea , Nymphaea candida . The highest production was reached for Nuphar lutea and Nymphaea alba in alkaline, eutrophic water bodies. The production per leaf was relatively high for both species in the acid water body. Nymphaea candida showed a very short vegetation period and low turnover rates. The ratio Total potential leaf biomass/Maximum potential leaf biomass (P/B max ) of the three species ranged from 1.35-2.25. The ratio Vegetation period (Period with floating leaves)/Mean leaf life span ranged from 2.94-4.63, the ratio Growth period (Period with appearance of new floating leaves)/Vegetation period from 0.53-0.73. The clear differences between Nymphaea candida versus Nuphar lutea and Nymphaea alba , may be due to adaptations of Nymphaea candida to an Euro-Siberic climate with short-lasting summer conditions.

  20. Plant traits and environment: floating leaf blade production and turnover of waterlilies

    Directory of Open Access Journals (Sweden)

    Peter F. Klok

    2017-04-01

    Full Text Available Floating leaf blades of waterlilies fulfill several functions in wetland ecosystems by production, decomposition and turnover as well as exchange processes. Production and turnover rates of floating leaf blades of three waterlily species, Nuphar lutea (L. Sm., Nymphaea alba L. and Nymphaea candida Presl, were studied in three freshwater bodies, differing in trophic status, pH and alkalinity. Length and percentages of leaf loss of marked leaf blades were measured weekly during the growing season. Area and biomass were calculated based on leaf length and were used to calculate the turnover rate of floating leaf blades. Seasonal changes in floating leaf production showed that values decreased in the order: Nymphaea alba, Nuphar lutea, Nymphaea candida. The highest production was reached for Nuphar lutea and Nymphaea alba in alkaline, eutrophic water bodies. The production per leaf was relatively high for both species in the acid water body. Nymphaea candida showed a very short vegetation period and low turnover rates. The ratio Total potential leaf biomass/Maximum potential leaf biomass (P/Bmax of the three species ranged from 1.35–2.25. The ratio Vegetation period (Period with floating leaves/Mean leaf life span ranged from 2.94–4.63, the ratio Growth period (Period with appearance of new floating leaves/Vegetation period from 0.53–0.73. The clear differences between Nymphaea candida versus Nuphar lutea and Nymphaea alba, may be due to adaptations of Nymphaea candida to an Euro-Siberic climate with short-lasting summer conditions.