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Sample records for surf smelt hypomesus

  1. A Covered Cod-End and Tow-Path Evaluation of Midwater Trawl Gear Efficiency for Catching Delta Smelt (Hypomesus transpacificus

    Directory of Open Access Journals (Sweden)

    Lara Mitchell

    2017-12-01

    Full Text Available https://doi.org/10.15447/sfews.2017v15iss4art3For nearly 50 years, the California Department of Fish and Wildlife has used a midwater trawl to intensively monitor fish populations in the San Francisco Estuary during the fall, sampling over 100 locations each month. The data collected have been useful for calculating indices of fish abundance and for detecting and documenting the decline of the endangered fish species delta smelt (Hypomesus transpacificus. However, efforts to calculate estimates of absolute abundance have been hampered by the lack of information on gear efficiency, in particular questions about contact selectivity and the effect of tow method on catches. To answer these questions we conducted a study that used a covered cod end on a net towed either near the surface, referred to as a surface tow, or throughout the water column, referred to as an oblique tow. A contact selectivity model was fit to estimate the probability that a delta smelt that has come into contact with the net is retained in the cod end of the net conditional on its body length. Full retention of delta smelt was found to occur around 60 mm fork length. Delta smelt catch densities for the surface tows were an order of magnitude greater than densities in the oblique tows, suggesting a surface orientation at the sub-adult life stage. These results represent an important step in being able to calculate absolute abundance estimates of the delta smelt population size using decades’ worth of monitoring data.

  2. Diet, Prey Selection, and Body Condition of Age-0 Delta Smelt, Hypomesus transpacificus, in the Upper San Francisco Estuary

    Directory of Open Access Journals (Sweden)

    Steven B. Slater

    2014-09-01

    Full Text Available Steven B. Slater and Randall D. Baxterdoi: http://dx.doi.org/10.15447/sfews.2014v12iss3art1The Delta Smelt, an endangered fish, has suffered a long-term decline in abundance, believed to result from, in part, to changes in the pelagic food web of the upper San Francisco Estuary. To investigate the current role of food as a factor in Delta Smelt well-being, we developed reference criteria for gut fullness and body condition based on allometric growth. We then examined monthly diet, prey selectivity, and gut fullness of larvae and juvenile Delta Smelt collected April through September in 2005 and 2006 for evidence of feeding difficulties leading to reduced body condition. Calanoid copepods Eurytemora affinis and Pseudodiaptomus forbesi remained major food items during spring and from early summer through fall, respectively. Other much larger copepods and macroinvertebrates contributed in lesser numbers to the diet of older juvenile fish from mid-summer through fall. In fall, juvenile Delta Smelt periodically relied heavily on very small prey and prey potentially associated with demersal habitat, suggesting typical pelagic food items were in short supply. We found a strong positive selection for E. affinis and P. forbesi, neutral to negative selection for evasive calanoid Sinocalanus doerrii, and neutral to negative selection for the small cyclopoid copepod Limnoithona tetraspina and copepod nauplii, which were consumed only when extremely numerous in the environment. Feeding incidence was significantly higher in 2006, but among successfully feeding fish we found no between year difference in gut fullness. However, we did detect differences in fullness across months in both years. We found no difference in body condition of Delta Smelt between years yet our sample sizes were low in September when Delta Smelt reverted to feeding on very small organisms and fullness declined, so the longer-term effect remains unknown. Our findings suggest that: Delta

  3. An updated conceptual model of Delta Smelt biology: Our evolving understanding of an estuarine fish

    Science.gov (United States)

    Baxter, Randy; Brown, Larry R.; Castillo, Gonzalo; Conrad, Louise; Culberson, Steven D.; Dekar, Matthew P.; Dekar, Melissa; Feyrer, Frederick; Hunt, Thaddeus; Jones, Kristopher; Kirsch, Joseph; Mueller-Solger, Anke; Nobriga, Matthew; Slater, Steven B.; Sommer, Ted; Souza, Kelly; Erickson, Gregg; Fong, Stephanie; Gehrts, Karen; Grimaldo, Lenny; Herbold, Bruce

    2015-01-01

    The main purpose of this report is to provide an up-to-date assessment and conceptual model of factors affecting Delta Smelt (Hypomesus transpacificus) throughout its primarily annual life cycle and to demonstrate how this conceptual model can be used for scientific and management purposes. The Delta Smelt is a small estuarine fish that only occurs in the San Francisco Estuary. Once abundant, it is now rare and has been protected under the federal and California Endangered Species Acts since 1993. The Delta Smelt listing was related to a step decline in the early 1980s; however, population abundance decreased even further with the onset of the “pelagic organism decline” (POD) around 2002. A substantial, albeit short-lived, increase in abundance of all life stages in 2011 showed that the Delta Smelt population can still rebound when conditions are favorable for spawning, growth, and survival. In this report, we update previous conceptual models for Delta Smelt to reflect new data and information since the release of the last synthesis report about the POD by the Interagency Ecological Program for the San Francisco Estuary (IEP) in 2010. Specific objectives include:

  4. Surfing wave climate variability

    Science.gov (United States)

    Espejo, Antonio; Losada, Iñigo J.; Méndez, Fernando J.

    2014-10-01

    International surfing destinations are highly dependent on specific combinations of wind-wave formation, thermal conditions and local bathymetry. Surf quality depends on a vast number of geophysical variables, and analyses of surf quality require the consideration of the seasonal, interannual and long-term variability of surf conditions on a global scale. A multivariable standardized index based on expert judgment is proposed for this purpose. This index makes it possible to analyze surf conditions objectively over a global domain. A summary of global surf resources based on a new index integrating existing wave, wind, tides and sea surface temperature databases is presented. According to general atmospheric circulation and swell propagation patterns, results show that west-facing low to middle-latitude coasts are more suitable for surfing, especially those in the Southern Hemisphere. Month-to-month analysis reveals strong seasonal variations in the occurrence of surfable events, enhancing the frequency of such events in the North Atlantic and the North Pacific. Interannual variability was investigated by comparing occurrence values with global and regional modes of low-frequency climate variability such as El Niño and the North Atlantic Oscillation, revealing their strong influence at both the global and the regional scale. Results of the long-term trends demonstrate an increase in the probability of surfable events on west-facing coasts around the world in recent years. The resulting maps provide useful information for surfers, the surf tourism industry and surf-related coastal planners and stakeholders.

  5. Turbidity and salinity affect feeding performance and physiological stress in the endangered delta smelt.

    Science.gov (United States)

    Hasenbein, Matthias; Komoroske, Lisa M; Connon, Richard E; Geist, Juergen; Fangue, Nann A

    2013-10-01

    Coastal estuaries are among the most heavily impacted ecosystems worldwide with many keystone fauna critically endangered. The delta smelt (Hypomesus transpacificus) is an endangered pelagic fish species endemic to the Sacramento-San Joaquin Estuary in northern California, and is considered as an indicator species for ecosystem health. This ecosystem is characterized by tidal and seasonal gradients in water parameters (e.g., salinity, temperature, and turbidity), but is also subject to altered water-flow regimes due to water extraction. In this study, we evaluated the effects of turbidity and salinity on feeding performance and the stress response of delta smelt because both of these parameters are influenced by water flows through the San Francisco Bay Delta (SFBD) and are known to be of critical importance to the completion of the delta smelt's life cycle. Juvenile delta smelt were exposed to a matrix of turbidities and salinities ranging from 5 to 250 nephelometric turbidity units (NTUs) and 0.2 to 15 parts per thousand (ppt), respectively, for 2 h. Best statistical models using Akaike's Information Criterion supported that increasing turbidities resulted in reduced feeding rates, especially at 250 NTU. In contrast, best explanatory models for gene transcription of sodium-potassium-ATPase (Na/K-ATPase)-an indicator of osmoregulatory stress, hypothalamic pro-opiomelanocortin-a precursor protein to adrenocorticotropic hormone (expressed in response to biological stress), and whole-body cortisol were affected by salinity alone. Only transcription of glutathione-S-transferase, a phase II detoxification enzyme that protects cells against reactive oxygen species, was affected by both salinity and turbidity. Taken together, these data suggest that turbidity is an important determinant of feeding, whereas salinity is an important abiotic factor influencing the cellular stress response in delta smelt. Our data support habitat association studies that have shown greater

  6. Medical Aspects of Surfing.

    Science.gov (United States)

    Renneker, Mark

    1987-01-01

    The medical aspects of surfing include ear and eye injuries and sprains and strains of the lower back and neck, as well as skin cancer from exposure to the sun. Treatment, rehabilitation, and prevention of these problems are discussed. Surfing is recommended as part of an exercise program for reasonably healthy people. (Author/MT)

  7. A Place to Call Home: A Synthesis of Delta Smelt Habitat in the Upper San Francisco Estuary

    Directory of Open Access Journals (Sweden)

    Ted Sommer

    2013-06-01

    Full Text Available We used a combination of published literature and field survey data to synthesize the available information about habitat use by delta smelt Hypomesus transpacificus, a declining native species in the San Francisco Estuary. Delta smelt habitat ranges from San Pablo and Suisun bays to their freshwater tributaries, including the Sacramento and San Joaquin rivers. In recent years, substantial numbers of delta smelt have colonized habitat in Liberty Island, a north Delta area that flooded in 1997. The species has a more upstream distribution during spawning as opposed to juvenile rearing periods. Post-larvae and juveniles tend to have a more downstream distribution during wetter years. Delta smelt are most common in low-salinity habitat (<6 psu with high turbidities (>12 NTU and moderate temperatures (7 °C to 25 °C. They do not appear to have strong substrate preferences, but sandy shoals are important for spawning in other osmerids. The evidence to date suggests that they generally require at least some tidal flow in their habitats. Delta smelt also occur in a wide range of channel sizes, although they seem to be rarer in small channels (<15 m wide. Nonetheless, there is some evidence that open water adjacent to habitats with long water-residence times (e.g. tidal marsh, shoal, low-order channels may be favorable. Other desirable features of delta smelt habitat include high calanoid copepod densities and low levels of submerged aquatic vegetation (SAV and the toxic algae Microcystis. Although enough is known to plan for large-scale pilot habitat projects, these efforts are vulnerable to several factors, most notably climate change, which will change salinity regimes and increase the occurrence of lethal temperatures. We recommend restoration of multiple geographical regions and habitats coupled with extensive monitoring and adaptive management. An overall emphasis on ecosystem processes rather than specific habitat features is also likely to be

  8. Implications for future survival of delta smelt from four climate change scenarios for the Sacramento–San Joaquin Delta, California

    Science.gov (United States)

    Brown, Larry R.; Bennett, William A.; Wagner, R. Wayne; Morgan-King, Tara; Knowles, Noah; Feyrer, Frederick; Schoellhamer, David H.; Stacey, Mark T.; Dettinger, Mike

    2013-01-01

    Changes in the position of the low salinity zone, a habitat suitability index, turbidity, and water temperature modeled from four 100-year scenarios of climate change were evaluated for possible effects on delta smelt Hypomesus transpacificus, which is endemic to the Sacramento–San Joaquin Delta. The persistence of delta smelt in much of its current habitat into the next century appears uncertain. By mid-century, the position of the low salinity zone in the fall and the habitat suitability index converged on values only observed during the worst droughts of the baseline period (1969–2000). Projected higher water temperatures would render waters historically inhabited by delta smelt near the confluence of the Sacramento and San Joaquin rivers largely uninhabitable. However, the scenarios of climate change are based on assumptions that require caution in the interpretation of the results. Projections like these provide managers with a useful tool for anticipating long-term challenges to managing fish populations and possibly adapting water management to ameliorate those challenges.

  9. Riders on the storm: selective tidal movements facilitate the spawning migration of threatened delta smelt in the San Francisco Estuary

    Science.gov (United States)

    Bennett, W.A.; Burau, Jon R.

    2015-01-01

    Migration strategies in estuarine fishes typically include behavioral adaptations for reducing energetic costs and mortality during travel to optimize reproductive success. The influence of tidal currents and water turbidity on individual movement behavior were investigated during the spawning migration of the threatened delta smelt, Hypomesus transpacificus, in the northern San Francisco Estuary, California, USA. Water current velocities and turbidity levels were measured concurrently with delta smelt occurrence at sites in the lower Sacramento River and San Joaquin River as turbidity increased due to first-flush winter rainstorms in January and December 2010. The presence/absence of fish at the shoal-channel interface and near the shoreline was quantified hourly over complete tidal cycles. Delta smelt were caught consistently at the shoal-channel interface during flood tides and near the shoreline during ebb tides in the turbid Sacramento River, but were rare in the clearer San Joaquin River. The apparent selective tidal movements by delta smelt would facilitate either maintaining position or moving upriver on flood tides, and minimizing advection down-estuary on ebb tides. These movements also may reflect responses to lateral gradients in water turbidity created by temporal lags in tidal velocities between the near-shore and mid-channel habitats. This migration strategy can minimize the energy spent swimming against strong river and tidal currents, as well as predation risks by remaining in turbid water. Selection pressure on individuals to remain in turbid water may underlie population-level observations suggesting that turbidity is a key habitat feature and cue initiating the delta smelt spawning migration.

  10. Critical Assessment of the Delta Smelt Population in the San Francisco Estuary, California

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    William A Bennett

    2005-09-01

    Full Text Available The delta smelt (Hypomesus transpacificus is a small and relatively obscure fish that has recently risen to become a major focus of environmental concern in California. It was formally abundant in the low-salinity and freshwater habitats of the northeastern San Francisco Estuary, but is now listed as threatened under the Federal and California State Endangered Species Acts. In the decade following the listings scientific understanding has increased substantially, yet several key aspects of its biology and ecological relationships within the highly urbanized estuary remain uncertain. A key area of controversy centers on impacts to delta smelt associated with exporting large volumes of freshwater from the estuary to supply California’s significant agricultural and urban water demands. The lack of appropriate data, however, impedes efforts to resolve these issues and develop sound management and restoration alternatives. Delta smelt has an unusual life history strategy relative to many fishes. Some aspects of its biology are similar to other coastal fishes, particularly salmonids. Smelts in the genus, Hypomesus, occur throughout the Pacific Rim, have variable life history strategies, and are able to adapt rapidly to local environments. By comparison, delta smelt has a tiny geographic range being confined to a thin margin of low salinity habitat in the estuary. It primarily lives only a year, has relatively low fecundity, and pelagic larvae; life history attributes that are unusual when compared with many fishes worldwide. A small proportion of delta smelt lives two years. These individuals are relatively highly fecund but are so few in number that their reproductive contribution only may be of benefit to the population after years of extremely poor spawning success and survival. Provisioning of reproductive effort by these older fish may reflect a bet-hedging tactic to insure population persistence. Overall, the population persists by maximizing

  11. Delta smelt habitat in the San Francisco Estuary: A reply to Manly, Fullerton, Hendrix, and Burnham’s “Comments on Feyrer et al. Modeling the effects of future outflow on the abiotic habitat of an imperiled estuarine fish"

    Science.gov (United States)

    Feyrer, Frederick V.; Newman, Ken B.; Nobriga, Matthew; Sommer, Ted

    2016-01-01

    Manly et al. (2015) commented on the approach we (Feyrer et al. 2011) used to calculate an index of the abiotic habitat of delta smelt Hypomesus transpacificus. The delta smelt is an annual fish species endemic to the San Francisco Estuary (SFE) in California, USA. Conserving the delta smelt population while providing reliability to California’s water supply with water diverted from the SFE ecosystem is a major management and policy issue. Feyrer et al. (2011) evaluated historic and projected future abiotic habitat conditions for delta smelt. Manly et al. (2015) specifically commented regarding the following: (1) use of an independent abundance estimate, (2) spatial bias in the habitat index, and (3) application of the habitat index to future climate change projections. Here, we provide our reply to these three topics. While we agree that some of the concepts raised by Manly et al. (2015) have the potential to improve habitat assessments and their application to climate change scenarios as knowledge is gained, we note that the Feyrer et al. (2011) delta smelt habitat index is essentially identical to one reconstructed using Manly et al.’s (2015) preferred approach (their model 8), as shown here in Fig. 1.

  12. The Science of Surfing Waves and Surfing Breaks - A Review

    OpenAIRE

    Scarfe, B. E.; Elwany, M. H.S.; Mead, S. T.; Black, K. P.

    2003-01-01

    Surfing breaks have great social and economic value for coastal communities. In order to preserve and enhance these resources, a common language is needed that will bridge the gap between the colloquial slang of surfers and the technical language of scientists and policy makers. This language is the science of surfing waves and surfing breaks, and the more it is developed and used, the easier relations will be between the interested parties. This paper will create the basis for such a languag...

  13. SURF Model Calibration Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-10

    SURF and SURFplus are high explosive reactive burn models for shock initiation and propagation of detonation waves. They are engineering models motivated by the ignition & growth concept of high spots and for SURFplus a second slow reaction for the energy release from carbon clustering. A key feature of the SURF model is that there is a partial decoupling between model parameters and detonation properties. This enables reduced sets of independent parameters to be calibrated sequentially for the initiation and propagation regimes. Here we focus on a methodology for tting the initiation parameters to Pop plot data based on 1-D simulations to compute a numerical Pop plot. In addition, the strategy for tting the remaining parameters for the propagation regime and failure diameter is discussed.

  14. MOCEAN SURF WEAR -MALLISTO

    OpenAIRE

    Lehtovaara, Hanna

    2013-01-01

    Surffi on urheilulaji, jossa kuljetaan aallon päällä surffilaudalla. Surffaus on lähtöisin Polynesiasta, mutta nykypäivänä surffausta harrastetaan ympäri maailmaa. Opinnäytetyö käsittelee surf wear -malliston suunnittelua ja toteuttamista omalle toi-minimelle Mocean. Työn tavoitteena oli suunnitella toimiva, mutta myös trendikäs mallisto naissurffareille. Mallisto sisältää bikineitä, surffipaitoja legginsejä ja shortseja. Mallisto on suunniteltu naissurffareille, jotka surffaavat lämpimis...

  15. Surfing surface gravity waves

    Science.gov (United States)

    Pizzo, Nick

    2017-11-01

    A simple criterion for water particles to surf an underlying surface gravity wave is presented. It is found that particles travelling near the phase speed of the wave, in a geometrically confined region on the forward face of the crest, increase in speed. The criterion is derived using the equation of John (Commun. Pure Appl. Maths, vol. 6, 1953, pp. 497-503) for the motion of a zero-stress free surface under the action of gravity. As an example, a breaking water wave is theoretically and numerically examined. Implications for upper-ocean processes, for both shallow- and deep-water waves, are discussed.

  16. Unlimited Relativistic Shock Surfing Acceleration

    International Nuclear Information System (INIS)

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  17. Surfing the quantum world

    CERN Document Server

    Levin, Frank S

    2017-01-01

    The ideas and phenomena of the quantum world are strikingly unlike those encountered in our visual world. Surfing the Quantum World shows why and how this is so. It does this via a historical review and a gentle introduction to the fundamental principles of quantum theory, whose core concepts and symbolic representations are used to explain not only "ordinary" microscopic phenomena like the properties of the hydrogen atom and the structure of the Periodic Table of the Elements, but also a variety of mind-bending phenomena. Readers will learn that particles such as electrons and photons can behave like waves, allowing them to be in two places simultaneously, why white dwarf and neutron stars are gigantic quantum objects, how the maximum height of mountains has a quantum basis, and why quantum objects can tunnel through seemingly impenetrable barriers. Included among the various interpretational issues addressed is whether Schrodinger's cat is ever both dead and alive.

  18. Losses of Sacramento River Chinook Salmon and Delta Smelt to Entrainment in Water Diversions in the Sacramento–San Joaquin Delta

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    Wim J. Kimmerer

    2008-06-01

    Full Text Available Pumping at the water export facilities in the southern Sacramento-San Joaquin Delta kills fish at and near the associated fish-salvage facilities. Correlative analyses of salvage counts with population indices have failed to provide quantitative estimates of the magnitude of this mortality. I estimated the proportional losses of Sacramento River Chinook salmon (Oncorhynchus tshawytscha and delta smelt (Hypomesus transpacificus to place these losses in a population context. The estimate for salmon was based on recoveries of tagged smolts released in the upper Sacramento River basin, and recovered at the fish-salvage facilities in the south Delta and in a trawling program in the western Delta. The proportion of fish salvaged increased with export flow, with a mean value around 10% at the highest export flows recorded. Mortality was around 10% if pre-salvage losses were about 80%, but this value is nearly unconstrained. Losses of adult delta smelt in winter and young delta smelt in spring were estimated from salvage data (adults corrected for estimated pre-salvage survival, or from trawl data in the southern Delta (young. These losses were divided by population size and accumulated over the respective seasons. Losses of adult delta smelt were 1–50% (median 15% although the highest value may have been biased upward. Daily losses of larvae and juveniles were 0–8%, and seasonal losses accumulated were 0–25% (median 13%. The effect of these losses on population abundance was obscured by subsequent 50-fold variability in survival from summer to fall.

  19. Surfing-related ocular injuries.

    Science.gov (United States)

    Kim, J W; McDonald, H R; Rubsamen, P E; Luttrull, J K; Drouilhet, J H; Frambach, D A; Boyer, D S; Lambrou, F H; Hendrick, A; Weiss, J N; Engstrom, R E; Ing, M

    1998-01-01

    This report evaluates the clinical characteristics of surfing-related ocular trauma to learn the nature of such injuries and propose possible preventive measures. The authors reviewed 11 cases of surfing-related eye injuries caused by direct trauma from the surfboard, studying their mechanism of injury, the associated ocular complications, and the anatomic and visual outcomes of surgical repair. Surfing-related ocular injuries occurred exclusively in young males (mean age, 24.8 years; range, 14-37 years). The mechanism of injury most frequently responsible was impact with the sharp nose of the surfboard following a fall. Serious posterior segment complications were observed in all 11 patients, with nine patients suffering ruptured globes. Despite immediate medical attention, five patients did not recover ambulatory levels of visual acuity (>5/200). Surfing-related ocular trauma presenting to the retinal specialist typically leaves the patient with a permanent visual disability. Important factors contributing to these high-velocity injuries include the sharply pointed nose of the surfboard and the leash keeping the surfer in close proximity to the board following a fall. A simple modification in surfboard design such as blunting the sharp nose of the surfboard, or appropriate protective guards fitted over the surfboard nose, should lessen the severity of such injuries.

  20. Conservation of Native Fishes of the San Francisco Estuary: Considerations for Artificial Propagation of Chinook Salmon, Delta Smelt, and Green Sturgeon

    Directory of Open Access Journals (Sweden)

    Joshua A. Israel

    2011-04-01

    Full Text Available Many native fishes in the San Francisco Estuary and its watersheds have reached all-time low abundances. Some of these declining species (e.g., Chinook salmon Oncorhynchus tschawytscha have been under artificial propagation for decades. For others (e.g., delta smelt, Hypomesus transpacificus, and green sturgeon, Acipenser medirostris, this management option is just beginning to be discussed and implemented. Propagation strategies, in which organisms spend some portion of their lives in captivity, pose well-documented genetic and ecological threats to natural populations. Negative impacts of propagation have been documented for all Central Valley Chinook salmon runs, but limited efforts have been made to adapt hatchery operations to minimize the genetic and ecological threats caused by propagated fishes. A delta smelt propagation program is undergoing intensive design and review for operations and monitoring. However, if limiting factors facing this species in its estuarine habitat are not effectively addressed, captive propagation may not be a useful conservation approach, regardless of how carefully the propagation activity is designed or monitored. Scientifically defensible, ecologically based restoration programs that include monitoring and research aimed at quantifying natural population vital rates should be fully implemented before there is any attempt to supplement natural populations of delta smelt. Green sturgeon are also likely to face risks from artificial propagation if a large–scale program is implemented before this species’ limiting factors are better understood. In each of these cases, restoring habitats, and reducing loss from human actions, are likely to be the best strategy for rebuilding and supporting self–sustaining populations.

  1. CouchSurfing - a choice for travellers

    OpenAIRE

    Skog, Christina

    2012-01-01

    The objective of this thesis was to examine the thoughts and prejudices CouchSurfing evoke in people who had not previously heard of CouchSurfing. Additionally, the views expressed by people who had previously heard about the phenomenon were also studied. The aim was also to determine how these prejudices affected the behaviour of people. The purpose was to understand different aspects and give a more comprehensive picture of CouchSurfing through this thesis. The theoretical framework of ...

  2. Smelting of Scandium by Microwave Irradiation

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    Satoshi Fujii

    2017-09-01

    Full Text Available Scandium is being explored as an alloying element for aluminum alloys, which are gaining importance as high-performance lightweight structural alloys in the transportation industry. A few years ago, Sc was also found to be suitable for use in electrical devices. High-Sc-content ScAlN thin films have attracted significant attention because of their strong piezoelectricity. The piezoelectric response of ScAlN suggests that ScAlN thin films formed on a hard substrate would be suitable surface acoustic wave wideband filters for next-generation wireless communication systems. However, it is often difficult to use ScAlN thin films in MEMS devices—including acoustic ones—because of the extremely high price of metallic Sc, given the difficulty associated with smelting it. Here, we propose a novel process for smelting Sc metal by microwave irradiation. Sc metal was able to be obtained successfully from ScF3 through a microwave-irradiation-based carbon reduction reaction. The reaction temperature for this reduction process was approximately 880°C, which is half of that for the conventional smelting process involving reduction with Ca. Thus, the proposed microwave irradiation process has significant potential for use in the smelting of Sc metal.

  3. Turbulent viscosity in natural surf zones

    NARCIS (Netherlands)

    Grasso, F.R.; Ruessink, B.G.

    2012-01-01

    Waves breaking in the shallow surf zone near the shoreline inject turbulence into the water column that may reach the bed to suspend sediment. Breaking-wave turbulence in the surf zone is, however, poorly understood, which is one of the reasons why many process-based coastal-evolution models

  4. Surf similarity and solitary wave runup

    DEFF Research Database (Denmark)

    Fuhrman, David R.; Madsen, Per A.

    2008-01-01

    The notion of surf similarity in the runup of solitary waves is revisited. We show that the surf similarity parameter for solitary waves may be effectively reduced to the beach slope divided by the offshore wave height to depth ratio. This clarifies its physical interpretation relative to a previ...... functional dependence on their respective surf similarity parameters. Important equivalencies in the runup of sinusoidal and solitary waves are thus revealed.......The notion of surf similarity in the runup of solitary waves is revisited. We show that the surf similarity parameter for solitary waves may be effectively reduced to the beach slope divided by the offshore wave height to depth ratio. This clarifies its physical interpretation relative...... to a previous parameterization, which was not given in an explicit form. Good coherency with experimental (breaking) runup data is preserved with this simpler parameter. A recasting of analytical (nonbreaking) runup expressions for sinusoidal and solitary waves additionally shows that they contain identical...

  5. Energy consumption in smelting reduction (SR) processes

    International Nuclear Information System (INIS)

    Assis, Paulo Santos; Salierno, Giovanni Felice; Fang, Jue; Mankhand, Tilak R.; Assis, Carlos Frederico Campos de

    2010-01-01

    In contrast, conventional processes use coke and hematite/sinter in the blast furnace, in SR processes, other alternative fuels and iron ore sources, like charcoal and fine iron ores, can be used to produce sponge iron. The use of these alternative sources, by SR processes, can reduce environmental impacts and lower production costs. At first, the concepts of the theoretical gas utilization ratio, the smelting heat of the iron ore and the effective calorific value of coal were introduced. Then, the reason for gas utilization ratio and its performance in the shaft as a reducer in the smelting process are discussed and calculated. The relationship between coal consumption and iron ore reduction in the fluidized bed are also discussed. Finally, the influence of post-combustion on coal consumption in an iron bath furnace are calculated and discussed. (author)

  6. The usage of color invariance in SURF

    Science.gov (United States)

    Meng, Gang; Jiang, Zhiguo; Zhao, Danpei

    2009-10-01

    SURF (Scale Invariant Feature Transform) is a robust local invariant feature descriptor. However, SURF is mainly designed for gray images. In order to make use of the information provided by color (mainly RGB channels), this paper presents a novel colored local invariant feature descriptor, CISURF (Color Invariance based SURF). The proposed approach builds the descriptors in a color invariant space, which stems from Kubelka-Munk model and provides more valuable information than the gray space. Compared with the conventional SURF and SIFT descriptors, the experimental results show that descriptors created by CISURF is more robust to the circumstance changes such as the illumination direction, illumination intensity, and the viewpoints, and are more suitable for the deep space background objects.

  7. Effect of smelt aluminium on mechanical properties of steels

    International Nuclear Information System (INIS)

    Ryabov, V.R.; Dykhno, I.S.; Deev, G.F.; Karikh, V.V.

    1987-01-01

    Effect of smelt aluminium on mechanical properties of armco-iron and 12 Kh18N10T steel is studied. It is stated that in smelt aluminium and aluminium alloy contact with armco-iron the sample ductility is decreased. Corrosion effect of smelt alluminium on (18Kh15N5AM3) steel in the form of reinforced wire in aluminium-steel KAS-1A composite material is investigted. It is stated in experiment that during smelt alluminium-steel contact interaction of heterogeneous phases takes place

  8. Small-Scale Surf Zone Geometric Roughness

    Science.gov (United States)

    2017-12-01

    using stereo imagery techniques. A waterproof two- camera system with self-logging and internal power was developed using commercial-off-the-shelf...estimates. 14. SUBJECT TERMS surface roughness, nearshore, aerodynamic roughness, surf zone, structure from motion, 3D imagery 15. NUMBER OF... power was developed using commercial-off-the- shelf components and commercial software for operations 1m above the sea surface within the surf zone

  9. Influence of practice time on surfing injuries

    Directory of Open Access Journals (Sweden)

    Natacha Verônica Bazanella

    Full Text Available Abstract Introduction: studying the influence of surfing on the prevalence of injuries may contribute to prevention. Objective: to analyze the influence of time practicing sports and the occurrence of previous surgery on the profile and prevalence of injuries caused by surfing. Methods: Sixty-six Brazilian surfers (26.16 ± 0.73 years old participated in this study. Anthropometric data, physical activity level, surfing practice time and the prevalence of injuries (type of injury, anatomical region affected, and mechanism of injury were evaluated. To assess which of the studied variables exerted significant influence on the mean number of injuries, a Poisson log-linear model was adjusted through R software (p < 0.05. Results: most surfers were classified as eutrophic (73%, very active (60.6%, had an average practice time of 10.1 ± 1 years, and were not members of a surfing federation (74%. It was also observed that 90.9% of participants reported injuries caused by surfing and 44.9% affected the lower limbs. The majority of these injuries affected the integumentary system (46.6%. The main mechanism of injury was impact with the board or seabed (40.4%. Furthermore, it was found that surfing federation members presented an average of 58.4% more injuries than non-members (p = 0.007. Surfers who had undergone previous surgeries showed an average number of injuries that was 56.9% higher than other surfers (p = 0.012. In addition, it was found that for each extra year of surfing, the average number of injuries increased by 2.5% (p = 0.0118. Conclusion: the average number of injuries increased with increment in time practicing the sport, previous surgery and membership in a surfing federation.

  10. Yunnan Smelting Group Examines an Aluminum Project for Possible Investment

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Tian Yong,General Manager of Yunnan Smelt- ing Group,has gone to Zha gai NuoEr in Heilongjiang Province with a study group to conduct a full careful examination on the feasi- bility of the investment in the aluminum pro- ject.Yunnan Smelting Group is a large-scale

  11. Gene surfing in expanding populations.

    Science.gov (United States)

    Hallatschek, Oskar; Nelson, David R

    2008-02-01

    Large scale genomic surveys are partly motivated by the idea that the neutral genetic variation of a population may be used to reconstruct its migration history. However, our ability to trace back the colonization pathways of a species from their genetic footprints is limited by our understanding of the genetic consequences of a range expansion. Here, we study, by means of simulations and analytical methods, the neutral dynamics of gene frequencies in an asexual population undergoing a continual range expansion in one dimension. During such a colonization period, lineages can fix at the wave front by means of a "surfing" mechanism [Edmonds, C.A., Lillie, A.S., Cavalli-Sforza, L.L., 2004. Mutations arising in the wave front of an expanding population. Proc. Natl. Acad. Sci. 101, 975-979]. We quantify this phenomenon in terms of (i) the spatial distribution of lineages that reach fixation and, closely related, (ii) the continual loss of genetic diversity (heterozygosity) at the wave front, characterizing the approach to fixation. Our stochastic simulations show that an effective population size can be assigned to the wave that controls the (observable) gradient in heterozygosity left behind the colonization process. This effective population size is markedly higher in the presence of cooperation between individuals ("pushed waves") than when individuals proliferate independently ("pulled waves"), and increases only sub-linearly with deme size. To explain these and other findings, we develop a versatile analytical approach, based on the physics of reaction-diffusion systems, that yields simple predictions for any deterministic population dynamics. Our analytical theory compares well with the simulation results for pushed waves, but is less accurate in the case of pulled waves when stochastic fluctuations in the tip of the wave are important.

  12. THE SUSTAINABILITY OF SURFING TOURISM AT REMOTE DESTINATIONS

    OpenAIRE

    Hugues Dit Ciles, Emily Kate

    2009-01-01

    Surfing is an increasing component of the adventure tourism sector. Growth in surfing as a lifestyle, sporting activity and industry has generated a surge of exploration and intrusion by surfing tourism into remote and vulnerable destinations worldwide in the "search" for uncrowded waves at uncharted locations. Consequendy, there have been concerns at the impacts of surfing tourism on coastal, island and marine areas, often characterised by fragile environments and host communi...

  13. Faktor Yang Mendorong Konsumen Membeli Produk Planet Surf

    OpenAIRE

    Nugraheni, Aninda

    2014-01-01

    Era Global kini memberikan persaingan ketat bagi beberapa merek produk dalam memasarkan produk. Hal mendasar dalam pemasaran produk dengan promosi yang dilakukan. Beberapa produk lokal dapat terkalahkan oleh merek produk luar. Penelitian ini mengenai produk Planet Surf yang merupakan merek luar mempunyai posisioning produk surfing atau beach wear. Planet Surf menjadi pilihan anak muda karena fashionable dan up-to-date. Planet Surf merupakan toko yang menjual pakaian, sepatu, tas, dompet, d...

  14. Marketing plan for online surfing magazine

    OpenAIRE

    Michna, Jakub

    2017-01-01

    Název: Marketing plan for online surfing magazine Cíle: The main aim of this thesis is to design a marketing plan for launching new online surfing magazine. This project would emerge from present online media Freeride.cz/Water, which adverse situation is going to be analyzed. Metody: Author used interviewing and personal survey as methods. Secondary data collection, PEST analysis and Google Analytics tool served as framework for resulting SWOT analysis. Výsledky: The marketing plan for one ye...

  15. SURF II: Characteristics, facilities, and plans

    International Nuclear Information System (INIS)

    Madden, R.P.; Canfield, R.; Furst, M.; Hamilton, A.; Hughey, L.

    1992-01-01

    This facility report describes the Synchrotron Ultraviolet Radiation Facility (SURF II) operated by the National Institute of Standards and Technology, Gaithersburg, Maryland. SURF II is a 300-MeV electron storage ring which provides well characterized continuum radiation from the far infrared to the soft x-ray region with the critical wavelength at 17.4 nm. Brief descriptions are given of the user facilities, the characteristics of the synchrotron radiation, the main storage ring, the injector system and each of the operating beam lines, and associated instruments. Further description is given of expansion plans for additional beam lines

  16. Recirculation of Chilean copper smelting dust with high impurities contents to the smelting process

    Energy Technology Data Exchange (ETDEWEB)

    Sano, H.; Fujisawa, T. [Nagoya Univ., Nagoya (Japan). EcoTopia Science Inst.; Montenegro, V. [Nagoya Univ., Nagoya (Japan). Dept. of Materials Science and Engineering

    2007-07-01

    Dust generated during the copper smelting process is generally stabilized using hydrometallurgical methods as it contains high concentrations of arsenic. In this laboratory study, dust was recirculated during the smelting process in order to recover more copper and decrease dust emissions while recovering more copper. The behaviour of impurities and their influence on matte quality was also investigated. Industrial matte, flue dust, slag, and copper concentrates from a Chilean smelter were used as test materials. Dust recirculation tests were conducted in a simulated electric furnace. Off-gases were collected in a reaction tube, and the condensed volatile matter, slag, and matte phases were analyzed for their elemental content by inductively coupled plasma atomic emission spectrometry. The distribution of arsenic (As); antimony (Sb), bismuth (Bi), lead (Pb), and zinc (Zn) were investigated by varying the amounts of dust recirculating to the smelting stage with 21 per cent of the oxygen. Results showed that distributions of all analyzed elements increased with recirculation. It was concluded that copper can be recovered using the dust recirculation technique. However, impurities may limit the efficacy of the dust recirculation process. 6 refs., 3 tabs., 4 figs.

  17. Smelting Associated with the Advanced Spent Fuel Conditioning Process

    International Nuclear Information System (INIS)

    Hur, J-M.; Jeong, M-S.; Lee, W-K.; Cho, S-H.; Seo, C-S.; Park, S-W.

    2004-01-01

    The smelting process associated with the advanced spent fuel conditioning process (ACP) of Korea Atomic Energy Research Institute was studied by using surrogate materials. Considering the vaporization behaviors of input materials, the operation procedure of smelting was set up as (1) removal of residual salts, (2) melting of metal powder, and (3) removal of dross from a metal ingot. The behaviors of porous MgO crucible during smelting were tested and the chemical stability of MgO in the salt-being atmosphere was confirmed

  18. An Analysis of the SURF Method

    Directory of Open Access Journals (Sweden)

    Edouard Oyallon

    2015-07-01

    Full Text Available The SURF method (Speeded Up Robust Features is a fast and robust algorithm for local, similarity invariant representation and comparison of images. Similarly to many other local descriptor-based approaches, interest points of a given image are defined as salient features from a scale-invariant representation. Such a multiple-scale analysis is provided by the convolution of the initial image with discrete kernels at several scales (box filters. The second step consists in building orientation invariant descriptors, by using local gradient statistics (intensity and orientation. The main interest of the SURF approach lies in its fast computation of operators using box filters, thus enabling real-time applications such as tracking and object recognition. The SURF framework described in this paper is based on the PhD thesis of H. Bay [ETH Zurich, 2009], and more specifically on the paper co-written by H. Bay, A. Ess, T. Tuytelaars and L. Van Gool [Computer Vision and Image Understanding, 110 (2008, pp. 346–359]. An implementation is proposed and used to illustrate the approach for image matching. A short comparison with a state-of-the-art approach is also presented, the SIFT algorithm of D. Lowe [International Journal of Computer Vision, 60 (2004, pp. 91–110], with which SURF shares a lot in common.

  19. Electron Surfing Acceleration in Magnetic Reconnection

    OpenAIRE

    Hoshino, Masahiro

    2005-01-01

    We discuss that energetic electrons are generated near the X-type magnetic reconnection region due to a surfing acceleration mechanism. In a thin plasma sheet, the polarization electric fields pointing towards the neutral sheet are induced around the boundary between the lobe and plasma sheet in association with the Hall electric current. By using a particle-in-cell simulation, we demonstrate that the polarization electric fields are strongly enhanced in an externally driven reconnection syst...

  20. The characterization of surf tourists in the Algarve

    OpenAIRE

    Frank, Fabia Hanna

    2014-01-01

    Dissertação de mestrado, Economia do Turismo e Desenvolvimento Regional, Faculdade de Economia, Universidade do Algarve, 2014 Even though surf tourism in Portugal is an economic activity with a steady growth rate, there are not many assessment studies available. Using a sample of 240 participants, this dissertation aims to characterize surf tourists that stay in surf camps in the Algarve. Nearly half of all respondents (49,2%) are German. A large proportion of respondents are s...

  1. Planktonic Subsidies to Surf-Zone and Intertidal Communities

    Science.gov (United States)

    Morgan, Steven G.; Shanks, Alan L.; MacMahan, Jamie H.; Reniers, Ad J. H. M.; Feddersen, Falk

    2018-01-01

    Plankton are transported onshore, providing subsidies of food and new recruits to surf-zone and intertidal communities. The transport of plankton to the surf zone is influenced by wind, wave, and tidal forcing, and whether they enter the surf zone depends on alongshore variation in surf-zone hydrodynamics caused by the interaction of breaking waves with coastal morphology. Areas with gently sloping shores and wide surf zones typically have orders-of-magnitude-higher concentrations of plankton in the surf zone and dense larval settlement in intertidal communities because of the presence of bathymetric rip currents, which are absent in areas with steep shores and narrow surf zones. These striking differences in subsidies have profound consequences; areas with greater subsidies support more productive surf-zone communities and possibly more productive rocky intertidal communities. Recognition of the importance of spatial subsidies for rocky community dynamics has recently advanced ecological theory, and incorporating surf-zone hydrodynamics would be an especially fruitful line of investigation.

  2. Uranium decontamination of common metals by smelting, a review (handbook)

    International Nuclear Information System (INIS)

    Mautz, E.W.; Briggs, G.G.; Shaw, W.E.; Cavendish, J.H.

    1975-01-01

    The published and unpublished literature relating to the smelting of common metals scrap contaminated with uranium-bearing compounds has been searched and reviewed. In general, standard smelting practice produces ingots having a low uranium content, particularly for ferrous, nickel, and copper metals or alloys. Aluminum recovered from uranium contaminated scrap shows some decontamination by smelting but the uranium content is not as low as for other metals. Due to the heterogeneous nature and origin of scrap metals contaminated with uranium, information is frequently missing as to the extent of the initial contamination and the degree of decontamination obtained. The uranium content of the final cast ingots is generally all that is available. Results are summarized below by the primary composition of the uranium contaminated scrap metal. (U.S.)

  3. 76 FR 9409 - National Emission Standards for Hazardous Air Pollutants: Primary Lead Smelting

    Science.gov (United States)

    2011-02-17

    ... National Emission Standards for Hazardous Air Pollutants: Primary Lead Smelting; Proposed Rule #0;#0... Emission Standards for Hazardous Air Pollutants: Primary Lead Smelting AGENCY: Environmental Protection... standards for hazardous air pollutants (NESHAP) for Primary Lead Smelting to address the results of the...

  4. Lidar and aerosol measurements over the surf zone

    NARCIS (Netherlands)

    Moerman, M.M.; Cohen, L.H.; Leeuw, G. de; Kunz, G.J.

    2001-01-01

    The aerosol produced by waves breaking in the surf zone is important for a variety of processes, such as transport of pollutants and bacteria, and electro optical propagation in the coastal zone. Yet, quantitative information on surf produced aerosol is very limited (de Leeuw et al., 2000). In the

  5. Surfing into spirituality and a new, aquatic nature religion.

    Science.gov (United States)

    Taylor, Bron

    2007-01-01

    "Soul surfers" consider surfing to be a profoundly meaningful practice that brings physical, psychological, and spiritual benefits. They generally agree on where surfing initially developed, that it assumed a religious character, was suppressed for religious reasons, has been undergoing a revival, and enjoins reverence for and protection of nature. This subset of the global surfing community should be understood as a new religious movement-a globalizing, hybridized, and increasingly influential example of what I call aquatic nature religion. For these individuals, surfing is a religious form in which a specific sensual practice constitutes its sacred center, and the corresponding experiences are constructed in a way that leads to a belief in nature as powerful, transformative, healing, and sacred. I advance this argument by analyzing these experiences, as well as the myths, rites, symbols, terminology, technology, material culture, and ethical mores that are found within surfing subcultures.

  6. The development of coke smelting and the industrial revolution

    OpenAIRE

    Macfarlane, Alan

    2004-01-01

    Abraham Darby and the origins of the industrial revolution in Britain. Alan Macfarlane talks to John about the reasons for the area near Birmingham becoming the epi-centre of the industrial development, and the development of coke furnaces and iron smelting.

  7. 31 CFR 101.5 - Payment of smelting costs.

    Science.gov (United States)

    2010-07-01

    ... FORFEITURE OF COUNTERFEIT GOLD COINS § 101.5 Payment of smelting costs. The petitioner shall be required to pay all reasonable costs incurred in extracting the bullion from the counterfeit coins, as shall be determined by the Assistant Secretary. Payment must be made prior to the return of the gold bullion to the...

  8. Project Update: ZVI Used for Arsenic from Lead Smelting Facility

    Science.gov (United States)

    The U.S. EPA Office of Research and Development’s National Risk Management Research Laboratory (NRMRL) is conducting long-term monitoring of a granular iron permeable reactive barrier (PRB) for remediation of ground water contaminated with arsenic from a former lead smelting faci...

  9. Delineation of surf scoter habitat in Chesapeake Bay, Maryland: macrobenthic and sediment composition of surf scoter feeding sites

    Science.gov (United States)

    Kidwell, D.M.; Perry, M.C.

    2005-01-01

    Surveys of surf scoters (Melanitta perspicillata) along the Atlantic coast of the United States have shown population declines in recent decades. The Chesapeake Bay has traditionally been a key wintering area for surf scoters. Past and present research has shown that bivalves constitute a major food item for seaducks in the Chesapeake Bay, with surf scoters feeding primarily on hooked mussel (Ischadium recurvum) and dwarf surf clam (Mulinia lateralis). Degraded water quality conditions in the Chesapeake Bay have been well documented and have been shown to greatly influence the composition of benthic communities. Large concentrations of feeding surf scoters (>500 individuals) in the Bay were determined through monthly boat surveys. Locations consistently lacking surf scoters were also determined. Macrobenthos were seasonally sampled at 3 locations containing scoters and 3 locations without scoters. A 1 kilometer square grid was superimposed over each location using GIS and sampling sites within the square were randomly chosen. Benthos were sampled at each site using SCUBA and a meter square quadrat. Biomass and size class estimates were determined for all bivalves within each kilometer square. Results indicated that scoter feeding sites contained significantly greater biomass of M. lateralis, I. recurvum, and Gemma gemma than locations where no scoters were present. Substrate differences were also detected, with scoter feeding sites being composed of a sand/shell mix while non-scoter sites consisted primarily of mud. This data indicates that surf scoters in the Chesapeake Bay are selecting areas with high densities of preferred food items, potentially maximizing there foraging energetics. In addition, two scoter feeding sites also contained a patchwork of eastern oyster (Crassostrea virginica) and oyster shell, on which much of the I. recurvum was attached. This suggests the possibility that surf scoters utilize eastern oyster habitat and the dramatic depletion of

  10. Youth Homelessness and Vulnerability: How Does Couch Surfing Fit?

    Science.gov (United States)

    Curry, Susanna R; Morton, Matthew; Matjasko, Jennifer L; Dworsky, Amy; Samuels, Gina M; Schlueter, David

    2017-09-01

    Youth homelessness is a problem characterized by high levels of vulnerability. The extent to which couch surfing - moving from one temporary housing arrangement to another - is part of youth homelessness is not well understood. Chapin Hall's Voices of Youth Count, a national research initiative, involves a multicomponent approach to studying youth homelessness. This study reports emerging findings regarding couch surfing and homelessness primarily from a national survey of 13,113 adults with youth ages 13-25 in their households or who are themselves ages 18-25. Findings suggest that couch surfing is relatively common, particularly among the older age group. Among households with 13- to 17-year-olds and 18- to 25-year-olds, 4.0% and 20.5%, respectively, reported that any of them had couch surfed in the last 12 months. There are notable social, economic, and educational differences, on average, between youth reporting homelessness and those reporting only couch surfing. However, most youth who report experiencing homelessness also report couch surfing, and these youth who experience both circumstances present high levels of socioeconomic vulnerability. Couch surfing encompasses a range of experiences, some of which likely include need for services. Interviews currently in the field, and expanded analysis of data, will contribute more nuanced policy insights. © Society for Community Research and Action 2017.

  11. Genome Surfing As Driver of Microbial Genomic Diversity.

    Science.gov (United States)

    Choudoir, Mallory J; Panke-Buisse, Kevin; Andam, Cheryl P; Buckley, Daniel H

    2017-08-01

    Historical changes in population size, such as those caused by demographic range expansions, can produce nonadaptive changes in genomic diversity through mechanisms such as gene surfing. We propose that demographic range expansion of a microbial population capable of horizontal gene exchange can result in genome surfing, a mechanism that can cause widespread increase in the pan-genome frequency of genes acquired by horizontal gene exchange. We explain that patterns of genetic diversity within Streptomyces are consistent with genome surfing, and we describe several predictions for testing this hypothesis both in Streptomyces and in other microorganisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Palmprint Based Verification System Using SURF Features

    Science.gov (United States)

    Srinivas, Badrinath G.; Gupta, Phalguni

    This paper describes the design and development of a prototype of robust biometric system for verification. The system uses features extracted using Speeded Up Robust Features (SURF) operator of human hand. The hand image for features is acquired using a low cost scanner. The palmprint region extracted is robust to hand translation and rotation on the scanner. The system is tested on IITK database of 200 images and PolyU database of 7751 images. The system is found to be robust with respect to translation and rotation. It has FAR 0.02%, FRR 0.01% and accuracy of 99.98% and can be a suitable system for civilian applications and high-security environments.

  13. Reproduction and recruitment patterns of the surf clam Donax serra ...

    African Journals Online (AJOL)

    Reproduction and recruitment patterns of the surf clam Donax serra (Bivalvia, Donacidae) on two ... Keywords: condition index, Donax serra, histology, Namibia, recruitment, reproduction, sandy beach ecology ... AJOL African Journals Online.

  14. Surface Wave Focusing and Acoustic Communications in the Surf Zone

    National Research Council Canada - National Science Library

    Preisig, James

    2004-01-01

    The forward scattering of acoustic signals off of shoaling surface gravity waves in the surf zone results in a time-varying channel impulse response that is characterized by intense, rapidly fluctuating arrivals...

  15. La importancia del patrocinio deportivo : el surf como última tendencia

    OpenAIRE

    Lvov a Zemlianskaia,Victoria

    2015-01-01

    Se pretende dar a conocer el motivo del constante incremento del patrocinio deportivo, concretamente en el mundo del surf. Esta estrategia de marketing es empleada por muchas marcas como clave del éxito en la diferenciación

  16. A role for Heparan Sulfate in Viral Surfing

    Science.gov (United States)

    Oh, Myung-Jin; Akhtar, Jihan; Desai, Prashant; Shukla, Deepak

    2009-01-01

    Heparan sulfate (HS) moieties on cell surfaces are known to provide attachment sites for many viruses including herpes simplex virus type-1 (HSV-1). Here we demonstrate that cells respond to HSV-1 infection by promoting filopodia formation. Filopodia express HS and are subsequently utilized for the transport of HSV-1 virions to cell bodies in a surfing-like phenomenon, which is facilitated by the underlying actin cytoskeleton and is regulated by transient activation of a small Rho GTPase, Cdc42. We also demonstrate that interaction between a highly conserved herpesvirus envelope glycoprotein B (gB) and HS is required for surfing. A HSV-1 mutant that lacks gB fails to surf and quantum-dots conjugated with gB demonstrate surfing-like movements. Our data demonstrates a novel use of a common receptor, HS, which could also be exploited by multiple viruses and quite possibly, many additional ligands for transport along the plasma membrane. PMID:19909728

  17. A role for heparan sulfate in viral surfing

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Myung-Jin; Akhtar, Jihan [Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612 (United States); Desai, Prashant [Viral Oncology Program, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, 1650 Orleans Street, Baltimore, MD 21231 (United States); Shukla, Deepak, E-mail: dshukla@uic.edu [Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612 (United States); Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612 (United States)

    2010-01-01

    Heparan sulfate (HS) moieties on cell surfaces are known to provide attachment sites for many viruses including herpes simplex virus type-1 (HSV-1). Here, we demonstrate that cells respond to HSV-1 infection by enhancing filopodia formation. Filopodia express HS and are subsequently utilized for the transport of HSV-1 virions to cell bodies in a surfing-like phenomenon, which is facilitated by the underlying actin cytoskeleton and is regulated by transient activation of a small Rho GTPase, Cdc42. We also demonstrate that interaction between a highly conserved herpesvirus envelope glycoprotein B (gB) and HS is required for surfing. A HSV-1 mutant that lacks gB fails to surf and quantum dots conjugated with gB demonstrate surfing-like movements. Our data demonstrates a novel use of a common receptor, HS, which could also be exploited by multiple viruses and quite possibly, many additional ligands for transport along the plasma membrane.

  18. Optimization of suspension smelting technology by computer simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lilius, K; Jokilaakso, A; Ahokainen, T; Teppo, O; Yongxiang, Yang [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

    1997-12-31

    An industrial-scale flash smelting furnace and waste-heat boilers have been modelled by using commercial Computational-Fluid-Dynamics software. The work has proceeded from cold gas flow to heat transfer, combustion, and two-phase flow simulations. In the present study, the modelling task has been divided into three sub-models: (1) the concentrate burner, (2) the flash smelting furnace (reaction shaft and uptake shaft), and (3) the waste-heat boiler. For the concentrate burner, the flow of the process gas and distribution air together with the concentrate or a feed mixture was simulated. Eulerian - Eulerian approach was used for the carrier gas-phase and the dispersed particle-phase. A large parametric study was carried out by simulating a laboratory scale burner with varying turbulence intensities and then extending the simulations to the industrial scale model. For the flash smelting furnace, the simulation work concentrated on gas and gas-particle two-phase flows, as well as the development of combustion model for sulphide concentrate particles. Both Eulerian and Lagrangian approaches have been utilised in describing the particle phase and the spreading of the concentrate in the reaction shaft as well as the particle tracks have been obtained. Combustion of sulphides was first approximated with gaseous combustion by using a built-in combustion model of the software. The real oxidation reactions of the concentrate particles were then coded as a user-defined sub-routine and that was tested with industrial flash smelting cases. For the waste-heat boiler, both flow and heat transfer calculations have been carried out for an old boiler and a modified boiler SULA 2 Research Programme; 23 refs.

  19. Nonmetallic inclusions in carbon steel smelted in plasma furnace

    Energy Technology Data Exchange (ETDEWEB)

    Shengelaya, I B; Kostyakov, V N; Nodiy, T K; Imerlishvili, V G; Gavisiani, A G [AN Gruzinskoj SSR, Tbilisi. Inst. Metallurgii

    1979-01-01

    A complex investigation on nonmetallic inclusions in carbon cast iron, smelted in plasma furnace in argon atmosphere and cast partly in the air and partly in argon atmosphere, has been carried out. As compared to open-hearth furnace carbon steel, the test metal was found to contain more oxide inclusions and nitrides; besides, in chromium-containing metal, chromium nitrides form the larger part of nitrides.

  20. Optimization of suspension smelting technology by computer simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lilius, K.; Jokilaakso, A.; Ahokainen, T.; Teppo, O.; Yang Yongxiang [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

    1996-12-31

    An industrial-scale flash smelting furnace and waste-heat boilers have been modelled by using commercial Computational-Fluid-Dynamics software. The work has proceeded from cold gas flow to heat transfer, combustion, and two-phase flow simulations. In the present study, the modelling task has been divided into three sub-models: (1) the concentrate burner, (2) the flash smelting furnace (reaction shaft and uptake shaft), and (3) the waste-heat boiler. For the concentrate burner, the flow of the process gas and distribution air together with the concentrate or a feed mixture was simulated. Eulerian - Eulerian approach was used for the carrier gas-phase and the dispersed particle-phase. A large parametric study was carried out by simulating a laboratory scale burner with varying turbulence intensities and then extending the simulations to the industrial scale model. For the flash smelting furnace, the simulation work concentrated on gas and gas-particle two-phase flows, as well as the development of combustion model for sulphide concentrate particles. Both Eulerian and Lagrangian approaches have been utilised in describing the particle phase and the spreading of the concentrate in the reaction shaft as well as the particle tracks have been obtained. Combustion of sulphides was first approximated with gaseous combustion by using a built-in combustion model of the software. The real oxidation reactions of the concentrate particles were then coded as a user-defined sub-routine and that was tested with industrial flash smelting cases. For the waste-heat boiler, both flow and heat transfer calculations have been carried out for an old boiler and a modified boiler SULA 2 Research Programme; 23 refs.

  1. Design requirements for a metal-smelting facility

    International Nuclear Information System (INIS)

    Williams, L.C.; Mack, J.E.

    1982-01-01

    Functional requirements for the smelting of metal scrap contaminated with low-enriched uranium in a Metal Smelting Faclity (MSF) have been determined. The process will be designed to smelt ferrous metal scrap that has accumulated at the Oak Ridge Gaseous Diffusion Plant (ORGDP) into one-ton ingots at a rate of 40 ingots per day (10,000 tons/year). Total scrap inventories at the ORGDP are currently estimated at 28,000 tons. The diffusion plant scrap is primarily contaminated with 100 to 200 ppm U at an enrichment of 0.5 to 1.5% 235 U. The scrap is considered special nuclear material (SNM) and cannot be handled by commercial smelters without specific licensing. Slagging will be performed to remove contaminants from the metal and concentrate them in the slag. Process systems will include scrap handling, size reduction, preheating and charging, melting and slagging, ingot casting and storage, and fume exhaust. The MSF has been proposed for FY 1984 line item funding

  2. Extracting phosphoric iron under laboratorial conditions smelting bog iron ores

    International Nuclear Information System (INIS)

    Török, B; Thiele, A

    2013-01-01

    In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well

  3. Directly smelted lead-tin alloys: A historical perspective

    Science.gov (United States)

    Dube, R. K.

    2010-08-01

    This paper discusses evidence related to the genesis and occurrence of mixed lead-tin ore deposit consisting of cassiterite and the secondary minerals formed from galena. These evidences belong to a very long time period ranging from pre-historic to as late as the nineteenth century a.d. This type of mixed ore deposits was smelted to prepare lead-tin alloys. The composition of the alloy depended on the composition of the starting ore mixture. A nineteenth century evidence for the production of directly smelted lead-tin alloys in southern Thailand is discussed. A unique and rather uncommon metallurgical terminology in Sanskrit language— Nāgaja—was introduced in India for the tin recovered from impure lead. This suggests that Indians developed a process for recovering tin from lead-tin alloys, which in all probability was based on the general principle of fire refining. It has been shown that in the context of India the possibility of connection between the word Nāgaja and the directly smelted lead-tin alloys cannot be ruled out.

  4. Designing of Synergistic Waste Mixtures for Multiphase Reactive Smelting

    Directory of Open Access Journals (Sweden)

    Vaso Manojlović

    2016-06-01

    Full Text Available Electric arc furnace (EAF dust, together with a mill scale and coke were smelted in a laboratory electric arc furnace. These metallurgical wastes consist of a many different phases and elements, making the reaction process complex. Thermo-chemical analysis of the reactions in metal, slag, and gas phases was done, and used for modeling of the mixture composition and energy consumption required for smelting. Modelling was performed with the software named RikiAlC. The crude ZnO, slag, and metal phase were analyzed using the atomic absorption spectrometry (AAS, the optical emission spectrometry with inductively coupled plasma (ICP-OES, the X-ray diffraction (XRD, the scanning electron microscopy (SEM equipped with energy dispersive spectrometry (EDS, and reflected and transmitted light microscopy. Also, in order to follow the behavior of this process the exhausted gases were monitored. The synergetic effects of the designed mixture may be recognized in minimizing energy consumption for the smelting process, improving the product yield efficiency, and reducing the negative environmental effects.

  5. Mercury distribution characteristics in primary manganese smelting plants

    International Nuclear Information System (INIS)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-01-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1–99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. - Graphical abstract: 1. Lack of data on mercury (Hg) distribution in manganese smelters. 2. Mass distribution of Hg released from 3 plants (as normalized values) were made as follows by measurements. 3. Information of distribution of Hg in Manganese smelters would be used for emission in to air and releases to other streams for the nation and globe in UNEP mercury report. - Highlights: • The mass balance study by on-site measurement from primary manganese smelting plants was made at first time in the world. • Hg distribution and main input and release pathways of Hg from primary manganese smelting plants could be found as the first time. • Gas temperature in bag filter affects Hg behavior and speciation changes in APCDs. • National inventory of Hg emssion has been updated with new data. - Mercury distribution in manganese smelting plant was investigated as the first measurements at commercial plants in the world. National Hg release

  6. The Effect of a Single Bout of Surfing on Exercise-Induced Affect.

    Science.gov (United States)

    Pittsinger, Ryan; Kress, Jeff; Crussemeyer, Jill

    2017-01-01

    Exercise-induced affect (EIA) has been well documented and is often composed of positive affect, negative affect, tranquility, and fatigue. Research on EIA has focused on mainstream sports such as running, walking, or cycling; however, no research has evaluated the influence of action sports participation in activities such surfing on EIA. The current study examined the effect of a single 30-min surfing bout on EIA in 107 adult volunteers. An additional purpose was if change in affect was similar based on surfing history, surfing frequency, and surfing skill level. To assess EIA, each participant completed the Physical Activity Affect Scale (PAAS) prior to and immediately following the 30-min surf session. Dependent t -tests were used to examine differences between pre- and post-test EIA. For the secondary purpose, a change score (PAAS posttest-PAAS pretest) was computed for each subscale. One-way ANOVAs were performed to determine differences among comparisons of surfing history, surfing frequency, and surfing skill level, and the change score for each of the 4 subscales. EIA was significantly altered by surfing, with significant improvements in positive affect and tranquility, and significant reductions in negative affect and fatigue. There were no significant differences among surfing history, surfing frequency, and surfing skill level, and positive affect, negative affect or tranquility. However, there were significant differences between fatigue and surfing history, surfing frequency, and surfing skill level. The results indicate that a single 30-min surfing bout may provide positive benefits for the participant. Implications for future surfing research and EIA are discussed.

  7. The Effect of a Single Bout of Surfing on Exercise-Induced Affect

    Science.gov (United States)

    PITTSINGER, RYAN; KRESS, JEFF; CRUSSEMEYER, JILL

    2017-01-01

    Exercise-induced affect (EIA) has been well documented and is often composed of positive affect, negative affect, tranquility, and fatigue. Research on EIA has focused on mainstream sports such as running, walking, or cycling; however, no research has evaluated the influence of action sports participation in activities such surfing on EIA. The current study examined the effect of a single 30-min surfing bout on EIA in 107 adult volunteers. An additional purpose was if change in affect was similar based on surfing history, surfing frequency, and surfing skill level. To assess EIA, each participant completed the Physical Activity Affect Scale (PAAS) prior to and immediately following the 30-min surf session. Dependent t-tests were used to examine differences between pre- and post-test EIA. For the secondary purpose, a change score (PAAS posttest-PAAS pretest) was computed for each subscale. One-way ANOVAs were performed to determine differences among comparisons of surfing history, surfing frequency, and surfing skill level, and the change score for each of the 4 subscales. EIA was significantly altered by surfing, with significant improvements in positive affect and tranquility, and significant reductions in negative affect and fatigue. There were no significant differences among surfing history, surfing frequency, and surfing skill level, and positive affect, negative affect or tranquility. However, there were significant differences between fatigue and surfing history, surfing frequency, and surfing skill level. The results indicate that a single 30-min surfing bout may provide positive benefits for the participant. Implications for future surfing research and EIA are discussed. PMID:29170700

  8. Reassessment of the predatory effects of rainbow smelt on ciscoes in Lake Superior

    Science.gov (United States)

    Myers, Jared T.; Jones, Michael L.; Stockwell, Jason D.; Yule, Daniel L.

    2009-01-01

    Evidence from small lakes suggests that predation on larval ciscoes Coregonus artedi by nonnative rainbow smelt Osmerus mordax can lead to cisco suppression or extirpation. However, evidence from larger lakes has led to equivocal conclusions. In this study, we examine the potential predation effects of rainbow smelt in two adjacent but contrasting embayments in Lake Superior (Thunder and Black bays, Ontario). During May 2006, we sampled the ichthyoplankton, pelagic fish communities, and diet composition of rainbow smelt in both bays. Using acoustics and midwater trawling, we estimated rainbow smelt densities to be 476 ± 34/ha (mean ± SE) in Thunder Bay and 3,435 ± 460/ha in Black Bay. We used a bioenergetics model to estimate the proportion of cisco larvae consumed by rainbow smelt. Our results suggest that predation by rainbow smelt accounts for 15–52% and 37–100% of the mortality of larval ciscoes in Thunder and Black bays, respectively, depending on the predator feeding rate and the scale of predator–prey overlap. We also examined the sensitivity of past conclusions (based on 1974 field collections) to assumptions of temporal overlap between rainbow smelt and larval ciscoes and estimates of rainbow smelt abundance derived from bottom trawl samples. After adjusting these parameters to reflect current understanding, we found that the previous predation estimates may have been conservative. We conclude that rainbow smelt may have been a more important contributor to the demise and slow recovery of ciscoes in Lake Superior than previously thought.

  9. The 'surf zone' in the stratosphere

    Science.gov (United States)

    McIntyre, M. E.; Palmer, T. N.

    Synoptic, coarse-grain, isentropic maps of Ertel's potential vorticity Q for the northern middle stratosphere, estimated using a large-Richardson-number approximation, are presented for a number of days in January-February 1979, together with some related isentropic trajectory calculations The effects of substituting FGGE for NMC base data are noted, as well as some slight corrections to maps published earlier. The combined evidence from the observations and from dynamical models strongly indicates the existence of planetary-wave breaking, a process in which material contours are rapidly and irreversibly deformed. In the winter stratosphere this occurs most spectacularly in a gigantic 'nonlinear critical layer', or 'surf zone', which surrounds the main polar vortex, and which tends to erode the vortex when wave amplitudes become large. Some of the FGGE-based Q maps suggest that we may be seeing glimpses of local dynamical instabilities and vortex-rollup phenomena within breaking planetary waves. Related phenomena in the troposphere are discussed. An objective definition of the area A( t) of the main vortex, as it appears on isentropic Q maps, is proposed. A smoothed time series of daily values of A( t) should be a statistically powerful 'circulation index' for the state of the winter-time middle stratosphere, which avoids the loss of information incurred by Eulerian space and time averaging.

  10. Ecological factors affecting Rainbow Smelt recruitment in the main basin of Lake Huron, 1976-2010

    Science.gov (United States)

    O'Brien, Timothy P.; Taylor, William W.; Roseman, Edward F.; Madenjian, Charles P.; Riley, Stephen C.

    2014-01-01

    Rainbow Smelt Osmerus mordax are native to northeastern Atlantic and Pacific–Arctic drainages and have been widely introduced throughout North America. In the Great Lakes region, Rainbow Smelt are known predators and competitors of native fish and a primary prey species in pelagic food webs. Despite their widespread distribution, importance as a prey species, and potential to negatively interact with native fish species, there is limited information concerning stock–recruitment relationships for Rainbow Smelt. To better understand recruitment mechanisms, we evaluated potential ecological factors determining recruitment dynamics for Rainbow Smelt in Lake Huron using data from bottom trawl catches. We specifically evaluated influence of stock size, environmental factors (water temperature, lake levels, and precipitation), and salmonine predation on the production of age-0 recruits from 1976 to 2010. Rainbow Smelt recruitment was negatively related to stock size exceeding 10 kg/ha, indicating that compensatory, density-dependent mortality from cannibalism or intraspecific competition was an important factor related to the production of age-0 recruits. Recruitment was positively related to spring precipitation suggesting that the amount of stream-spawning habitat as determined by precipitation was important for the production of strong Rainbow Smelt recruitment. Additionally, density of age-0 Rainbow Smelt was positively related to Lake Trout Salvelinus namaycush abundance. However, spawning stock biomass of Rainbow Smelt, which declined substantially from 1989 to 2010, was negatively associated with Lake Trout catch per effort suggesting predation was an important factor related to the decline of age-2 and older Rainbow Smelt in Lake Huron. As such, we found that recruitment of Rainbow Smelt in Lake Huron was regulated by competition with or cannibalism by older conspecifics, spring precipitation influencing stream spawning habitats, and predation by Lake Trout on

  11. Stopover habitats of spring migrating surf scoters in southeast Alaska

    Science.gov (United States)

    Lok, E.K.; Esler, Daniel; Takekawa, John Y.; De La Cruz, S.W.; Sean, Boyd W.; Nysewander, D.R.; Evenson, J.R.; Ward, D.H.

    2011-01-01

    Habitat conditions and nutrient reserve levels during spring migration have been suggested as important factors affecting population declines in waterfowl, emphasizing the need to identify key sites used during spring and understand habitat features and resource availability at stopover sites. We used satellite telemetry to identify stopover sites used by surf scoters migrating through southeast Alaska during spring. We then contrasted habitat features of these sites to those of random sites to determine habitat attributes corresponding to use by migrating scoters. We identified 14 stopover sites based on use by satellite tagged surf scoters from several wintering sites. We identified Lynn Canal as a particularly important stopover site for surf scoters originating throughout the Pacific winter range; approximately half of tagged coastally migrating surf scoters used this site, many for extended periods. Stopover sites were farther from the mainland coast and closer to herring spawn sites than random sites, whereas physical shoreline habitat attributes were generally poor predictors of site use. The geography and resource availability within southeast Alaska provides unique and potentially critical stopover habitat for spring migrating surf scoters. Our work identifies specific sites and habitat resources that deserve conservation and management consideration. Aggregations of birds are vulnerable to human activity impacts such as contaminant spills and resource management decisions. This information is of value to agencies and organizations responsible for emergency response planning, herring fisheries management, and bird and ecosystem conservation. Copyright ?? 2011 The Wildlife Society.

  12. DIOPS: A PC-Based Wave, Tide and Surf Prediction System

    National Research Council Canada - National Science Library

    Allard, Richard; Dykes, James; Kaihatu, James; Wakeham, Dean

    2005-01-01

    The Distributed Integrated Ocean Prediciton System (DIOPS) is a PC-based wave tide and surf prediction system designed to provide DoD accurate and timely surf predictions for essentially any world-wide location...

  13. Goddard and Caldwell: Oahu, Hawaii surf observation data set for 1968 - 2004 (NODC Accession 0001754)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surf reports are typically made several times per day at select locations around Oahu, primarily by Honolulu City and County lifeguards and the Surf News Network,...

  14. Goddard and Caldwell Oahu, Hawaii Surf Observation Dataset for 1968-2004 (NODC Accession 0001754)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surf reports are typically made several times per day at select locations around Oahu, primarily by Honolulu City and County lifeguards and the Surf News Network,...

  15. Moessbauer study of ancient iron smelting slag in Japan

    International Nuclear Information System (INIS)

    Nakanishi, A.

    2008-01-01

    For an investigation of the ancient iron manufacturing technique, a reproducing experiment was carried out by archaeologists, where ancient type of iron smelting furnace was built and iron sand with high titanium contents was used as the raw material. During the operation of furnace, a large amount of slag flowed away from the furnace. In order to investigate the possibility for the estimation about the operative condition of furnace and the raw material, 57 Fe Moessbauer spectroscopy was applied for characterizing these slags and it was found that these slags mainly consisted of ferropseudobrookite (FeTi 2 O 5 ).

  16. State of the art of smelting lead-acid battery scrap

    Energy Technology Data Exchange (ETDEWEB)

    Melin, A

    1977-02-01

    A discussion is given of the economic importance of lead recovery and of scrap recycling in the battery industry. Various possibiliies of processing battery scrap, either by direct smelting or by smelting after preparaton are discussed, and the BBU, the Stolberger, and the Tonnolli methods are compared

  17. EVALUATION OF SIFT AND SURF FOR VISION BASED LOCALIZATION

    Directory of Open Access Journals (Sweden)

    X. Qu

    2016-06-01

    Full Text Available Vision based localization is widely investigated for the autonomous navigation and robotics. One of the basic steps of vision based localization is the extraction of interest points in images that are captured by the embedded camera. In this paper, SIFT and SURF extractors were chosen to evaluate their performance in localization. Four street view image sequences captured by a mobile mapping system, were used for the evaluation and both SIFT and SURF were tested on different image scales. Besides, the impact of the interest point distribution was also studied. We evaluated the performances from for aspects: repeatability, precision, accuracy and runtime. The local bundle adjustment method was applied to refine the pose parameters and the 3D coordinates of tie points. According to the results of our experiments, SIFT was more reliable than SURF. Apart from this, both the accuracy and the efficiency of localization can be improved if the distribution of feature points are well constrained for SIFT.

  18. Car surfing: an uncommon cause of traumatic injury.

    Science.gov (United States)

    Peterson, T; Timberlake, G; Yeager, A; Jadali, M; Royer, K

    1999-02-01

    Car surfing is an infrequent cause of traumatic injuries treated by emergency physicians. This very dangerous activity can result in serious injury or death. We report 5 cases of injuries caused by car surfing seen at our hospital during 1996 and 1997. All involved head injuries after a fall from a moving motor vehicle. There were 3 male and 2 female patients, and 3 cases were fatal. Health care providers should be aware of this type of injury and support efforts to prevent it.

  19. Émergences et diffusions mondiales du surf

    OpenAIRE

    Coëffé, Vincent; Guibert, Christophe; Taunay, Benjamin

    2013-01-01

    La diffusion du surf à travers le monde illustre les dimensions matérielles et idéelles d’un processus singulier qui dépasse la simple question des règles sportives et des possibilités économiques de pratique. La problématique de la mondialisation du surf – et donc de ses « codages » symboliques à travers le monde – contribue ainsi à questionner les sports comme exemples de processus d’appropriation des pratiques et des normes culturelles qui leur sont associées. Sont ainsi analysées les émer...

  20. Copper smelting and sediment pollution in Bronze Age China.

    Science.gov (United States)

    Zhang, S.; Dong, G.

    2017-12-01

    The emergence and diffusion of metallurgical technology had tremendous environmental consequence, however, the spatial-temporal consequences of the metallurgy during Bronze Age are not clear in China. Here, Xray fluorescence (XRF) measurement and principal component analysis (PCA) were conducted on heavy metal element (Cu, Ni, Pb, Zn, Cr and As) concentrations (HMEC) of natural and anthropogenic sediment samples systematically collected from 22 late Neolithic-Bronze Age sites in Hexi corridor to explore the potential for subcontinental-wide changes in soil geochemistry. We place this data within the context of the Cu concentrations in lacustrine sediments located near smelting and mining centers in Bronze Age China. Our results show that variation of HMEC in anthropogenic sediment in Hexi corridor is contemporaneous with the increases of the Cu concentrations in lacustrine sediment around 4000 BP. Comparative data suggests the metallurgical production diffused from the Hexi corridor to central and southwestern China around 3600 BP. We argue that sediment pollution is not an isolated phenomenon during the Bronze Age China, but rather occurred on regional scales and is closely related to the intensity of smelting activities.

  1. Preparation of Inconel 740 superalloy by electron beam smelting

    Energy Technology Data Exchange (ETDEWEB)

    You, Xiaogang [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China); Tan, Yi, E-mail: tanyi@dlut.edu.cn [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China); You, Qifan; Shi, Shuang; Li, Jiayan [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China); Ye, Fei [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Wei, Xin [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China)

    2016-08-15

    A novel method, namely electron beam smelting (EBS) technology was used to prepare the Inconel 740 superalloy. The microstructures, hardness and oxidation behavior were characterized and compared with the traditionally prepared Inconel 740 superalloy. The results imply that the solution treatment gives rise to the coarsening of γ′ precipitates, with further aging treatment, the γ′ precipitates with size of less than 30 nm are distributed dispersively in the matrix, leading to a decreasing of the lattice parameters and an increasing of the misfit. The γ′ precipitates result in shearing mechanism of weakly pair coupling. The EBS 740 superalloy produces better properties than that prepared in the traditional method in both precipitation strengthening effect and oxidation resistance. - Highlights: • Electron beam smelting, a new method, was used to prepare the Inconel 740 superalloy. • The EBS 740 shows higher strengthening effect than 740 made in traditional method. • The EBS 740 shows better oxidation resistance than traditional 740. • It shows application prospect of EBS technology in preparing Ni-base superalloys.

  2. Droplets move over viscoelastic substrates by surfing a ridge

    NARCIS (Netherlands)

    Karpitschka, S.; Das, S.; van Gorcum, M.; Perrin, H.; Andreotti, B.; Snoeijer, J.H.

    2015-01-01

    Liquid drops on soft solids generate strong deformations below the contact line, resulting from a balance of capillary and elastic forces. The movement of these drops may cause strong, potentially singular dissipation in the soft solid. Here we show that a drop on a soft substrate moves by surfing a

  3. SurfCut: Free-Boundary Surface Extraction

    KAUST Repository

    Algarni, Marei Saeed Mohammed; Sundaramoorthi, Ganesh

    2016-01-01

    We present SurfCut, an algorithm for extracting a smooth simple surface with unknown boundary from a noisy 3D image and a seed point. In contrast to existing approaches that extract smooth simple surfaces with boundary, our method requires less user

  4. SURF'S UP! – Protein classification by surface comparisons

    Indian Academy of Sciences (India)

    Prakash

    encounter large protein families with only a few members of ... server for analysis of functional relationships in protein families, as inferred from protein surface maps comparison ... features, SURF'S UP! can work with models obtained from comparative modelling. ... 1997) or, if the user is confident in the quality of automated.

  5. Modeling and Simulation for a Surf Zone Robot

    Science.gov (United States)

    2012-12-14

    Figure 1.6: A picture Carmel River State Beach near Monterey, California showing a typical surf zone enviroment . Features include submerged and exposed...picture of the enviroment [34]. Another benefit that will be gained from the use of ROS for navigation is the direct integration of Gazebo and the

  6. Dorsal finger texture recognition: Investigating fixed-length SURF

    DEFF Research Database (Denmark)

    Hartung, Daniel; Kückelhahn, Jesper

    2012-01-01

    We seek to create fixed-length features from dorsal finger skin images extracted by the SURF interest point detector to combine it in the privacy enhancing helper data scheme. The source of the biometric samples is the GUC45 database which features finger vein, fingerprint and dorsal finger skin...

  7. Cross-shore currents in the surf zone

    DEFF Research Database (Denmark)

    Aagaard, Troels; Vinther, Niels

    2008-01-01

      While the dynamics and kinematics of various types of mean cross-shore current flows in the surf zone (undertow and rip currents) are fairly well understood, the causes for transitions occurring between these two types of mean circulation patterns remain obscure. On longshore barred beaches...

  8. Tracking image features with PCA-SURF descriptors

    CSIR Research Space (South Africa)

    Pancham, A

    2015-05-01

    Full Text Available IAPR International Conference on Machine Vision Applications, May 18-22, 2015, Tokyo, JAPAN Tracking Image Features with PCA-SURF Descriptors Ardhisha Pancham CSIR, UKZN South Africa apancham@csir.co.za Daniel Withey CSIR South Africa...

  9. Juveniles, food and the surf zone habitat: implications for teleost ...

    African Journals Online (AJOL)

    The length composition, abundance patterns and feeding habits of ... recorded off King's Beach only the aforementioned species ..... Christensen (1978) gives the distribution of the streepie, .... plankton in the surf zone and inshore waters of the Eastern .... abundance and diversity of the Swartkops estuary ichthyofauna.

  10. Anthropometric and Performance Perspectives of Female Competitive Surfing

    Directory of Open Access Journals (Sweden)

    Barlow Matthew John

    2016-09-01

    Full Text Available Purpose. To evaluate the anthropometric profiles of female surfers and to identify whether any anthropometrical factors might predict competitive ranking. Secondly, to evaluate the activity profile of female competitive surfing with respect to environmental conditions using Global Positioning System (GPS derived measures.

  11. Enrichment of Gold in Antimony Matte by Direct Smelting of Refractory Gold Concentrate

    Science.gov (United States)

    Yang, Tianzu; Xie, Boyi; Liu, Weifeng; Zhang, Duchao; Chen, Lin

    2018-04-01

    Conventional cyanidation technology achieves low gold recovery when used to process refractory gold concentrate. Based on the geochemical characteristics of gold deposit mineralization, a new method is proposed herein for gold enrichment in antimony matte by smelting of refractory gold concentrate. The effects of the FeO/SiO2 and CaO/SiO2 ratios, smelting temperature, and smelting time on the gold recovery were investigated in detail. The optimum conditions were determined to be FeO/SiO2 ratio of 1.2, CaO/SiO2 ratio of 0.4, smelting temperature of 1200°C, and smelting time of 45 min. The gold content in antimony matte and smelting slag was 96.68 and 1.13 g/t, respectively. The gold, antimony, and arsenic recovery was 97.72%, 26.89%, and 6.56%, respectively, with most of the antimony and arsenic volatilized into dust. Mineral liberation analyzer results showed that the antimony matte mainly consisted of FeS and FeO, with three phases, viz. FeAs, SbAs, and AuSb, embedded between them, indicating that gold was easily enriched with antimony and arsenic during smelting of refractory gold concentrate.

  12. Enrichment of Gold in Antimony Matte by Direct Smelting of Refractory Gold Concentrate

    Science.gov (United States)

    Yang, Tianzu; Xie, Boyi; Liu, Weifeng; Zhang, Duchao; Chen, Lin

    2018-06-01

    Conventional cyanidation technology achieves low gold recovery when used to process refractory gold concentrate. Based on the geochemical characteristics of gold deposit mineralization, a new method is proposed herein for gold enrichment in antimony matte by smelting of refractory gold concentrate. The effects of the FeO/SiO2 and CaO/SiO2 ratios, smelting temperature, and smelting time on the gold recovery were investigated in detail. The optimum conditions were determined to be FeO/SiO2 ratio of 1.2, CaO/SiO2 ratio of 0.4, smelting temperature of 1200°C, and smelting time of 45 min. The gold content in antimony matte and smelting slag was 96.68 and 1.13 g/t, respectively. The gold, antimony, and arsenic recovery was 97.72%, 26.89%, and 6.56%, respectively, with most of the antimony and arsenic volatilized into dust. Mineral liberation analyzer results showed that the antimony matte mainly consisted of FeS and FeO, with three phases, viz. FeAs, SbAs, and AuSb, embedded between them, indicating that gold was easily enriched with antimony and arsenic during smelting of refractory gold concentrate.

  13. Strategic Management at Mormaii - the Brazilian Surf Industry Leader

    Directory of Open Access Journals (Sweden)

    Marcos Abilio Bosquetti

    2017-01-01

    Full Text Available The sport of surfing has been growing rapidly in popularity worldwide and Brazil is among the countries with the largest surfing population, behind the United States and Australia, however, multinational surf companies are rushing in emerging markets like Brazil to find new opportunities for growth. This paper intends to provide insights on how local companies in these markets can overcome and even take advantage of differences with global competitors by re-thinking their core competencies and business models. Therefore, empirical research applying qualitative case study methodology was developed to investigate the role of strategy in the surf industry - a fairly unexplored research topic. Semi-structured in-depth interviews with the founder and CEO and the executive directors at the Brazilian surf industry leader - Mormaii, were conducted to understand how the 4-decade local company found its way to success. Although the theories: RBV, Core Competencies, and Dynamic Capabilities complement each other and help to explain firms’ performance and strategic choices, in empirical studies strategy has been analyzed only by one or another theory. Therefore, the simultaneous use of these three theories intended to fill this gap in the literature and bring more consistency to the discussion of this case study. As a result, this empirical study illustrates the RBV perspective, which stems from the principle that the source of firms’ competitive advantage lies in their internal resources and capabilities, rather than simply evaluating environmental opportunities and threats in conducting business. It also highlights the role that core competence and dynamic capabilities play in the company’s virtuous circle of sustainable growth and provides practitioners clues for re-thinking their strategies.

  14. Adaptive PCA based fault diagnosis scheme in imperial smelting process.

    Science.gov (United States)

    Hu, Zhikun; Chen, Zhiwen; Gui, Weihua; Jiang, Bin

    2014-09-01

    In this paper, an adaptive fault detection scheme based on a recursive principal component analysis (PCA) is proposed to deal with the problem of false alarm due to normal process changes in real process. Our further study is also dedicated to develop a fault isolation approach based on Generalized Likelihood Ratio (GLR) test and Singular Value Decomposition (SVD) which is one of general techniques of PCA, on which the off-set and scaling fault can be easily isolated with explicit off-set fault direction and scaling fault classification. The identification of off-set and scaling fault is also applied. The complete scheme of PCA-based fault diagnosis procedure is proposed. The proposed scheme is first applied to Imperial Smelting Process, and the results show that the proposed strategies can be able to mitigate false alarms and isolate faults efficiently. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Prevalence of Pterygia in Hawaii: Examining Cumulative Surfing Hours as a Risk Factor.

    Science.gov (United States)

    Lin, Alexander D; Miles, Ku'ulei; Brinks, Mitchel V

    2016-08-01

    To examine the association between surfing and pterygium prevalence in Hawaii. A convenience sampling was performed at four beaches on the island of Oahu, Hawaii. A total of 169 individuals were interviewed and underwent penlight examination to assess grade and extent of pterygium. Of 169 participants aged 18-80 years, 88 non-surfers, 41 occasional surfers, 15 recreational surfers and 25 surfing enthusiasts were identified based on their lifetime surfing hours. Overall, 19 participants were found to have pterygia (28 pterygia total) including two non-surfers (2.3%), five occasional surfers (12.2%), three recreational surfers (20.0%), and nine enthusiast surfers (36.0%). Variables associated with pterygium prevalence were lifetime surfing hours (p surfing hours as the primary explanatory variable. After adjustment for confounders, a significant linear relationship was observed between chord length and lifetime surfing hours (p = 0.01). Surfing was associated with an increased pterygium prevalence and trend towards an association with increased pterygium severity. Increased risk of exposure to wind, particle irritation, and ultraviolet (UV) radiation while surfing may contribute to pterygium development. Implications for public health include promoting UV protective eyewear during surfing, in addition to raising awareness about the association of pterygia and the sport of surfing.

  16. Delta smelt: Life history and decline of a once abundant species in the San Francisco Estuary

    Science.gov (United States)

    Moyle, Peter B.; Brown, Larry R.; Durand, John R; Hobbs, James A.

    2016-01-01

    This paper reviews what has been learned about Delta Smelt and its status since the publication of The State of Bay-Delta Science, 2008 (Healey et al. 2008). The Delta Smelt is endemic to the upper San Francisco Estuary. Much of its historic habitat is no longer available and remaining habitat is increasingly unable to sustain the population. As a listed species living in the central node of California’s water supply system, Delta Smelt has been the focus of a large research effort to understand causes of decline and identify ways to recover the species. Since 2008, a remarkable record of innovative research on Delta Smelt has been achieved, which is summarized here. Unfortunately, research has not prevented the smelt’s continued decline, which is the result of multiple, interacting factors. A major driver of decline is change to the Delta ecosystem from water exports, resulting in reduced outflows and high levels of entrainment in the large pumps of the South Delta. Invasions of alien species, encouraged by environmental change, have also played a contributing role in the decline. Severe drought effects have pushed Delta Smelt to record low levels in 2014–2015. The rapid decline of the species and failure of recovery efforts demonstrate an inability to manage the Delta for the “co-equal goals” of maintaining a healthy ecosystem and providing a reliable water supply for Californians. Diverse and substantial management actions are needed to preserve Delta Smelt.

  17. An Aerial Video Stabilization Method Based on SURF Feature

    Directory of Open Access Journals (Sweden)

    Wu Hao

    2016-01-01

    Full Text Available The video captured by Micro Aerial Vehicle is often degraded due to unexpected random trembling and jitter caused by wind and the shake of the aerial platform. An approach for stabilizing the aerial video based on SURF feature and Kalman filter is proposed. SURF feature points are extracted in each frame, and the feature points between adjacent frames are matched using Fast Library for Approximate Nearest Neighbors search method. Then Random Sampling Consensus matching algorithm and Least Squares Method are used to remove mismatching points pairs, and estimate the transformation between the adjacent images. Finally, Kalman filter is applied to smooth the motion parameters and separate Intentional Motion from Unwanted Motion to stabilize the aerial video. Experiments results show that the approach can stabilize aerial video efficiently with high accuracy, and it is robust to the translation, rotation and zooming motion of camera.

  18. Surf zone Exchange on a Rip Channeled Beach

    Science.gov (United States)

    Reniers, A.; Macmahan, J.

    2008-12-01

    The dispersion and surf zone exchange of GPS-equipped surface drifters observed during the Rip Current EXperiment (RCEX) is examined with help of Lagrangian Coherent Structures (LCSs). LCSs allow for the detection of transport barriers in unsteady flows and are typically applied to shelf-scale circulation systems. Here LCSs are specifically computed to detect the effects of surfzone-originated Very Low Frequency motions (VLFs) with O(10) minute time scale on the cross-shore exchange of floating material using numerical model calculations of the Lagrangian surface velocity at the wave group timescale. After verification with RCEX field observations, the model is run for a range of environmental conditions experienced during the field experiment to assess the effects of VLFs on the cross-shore surf zone exchange. Results are relevant for (but not restricted to) sediment and nutrient exchange, human health, water clarity, and swimmer safety.

  19. Monitoring system specifications: retrieval of surf from a salt repository

    International Nuclear Information System (INIS)

    1980-01-01

    The task of developing specifications for a reference monitoring system determined by repository environmental conditions, retrieval operations, and federal regulatory criteria is discussed. The monitoring system specified in this report is capable of measuring (1) package position and orientation, (2) vault deformation, (3) brine accumulation, (4) spent fuel dissolution, (5) temperature, (6) nuclear radiation, and (7) package condition with sufficient accuracy to provide data input to a general risk assessment model. In order to define a monitoring system which can provide probabilistic data on radiological risk to operating personnel and the general public for a salt mine repository, the following information is required: (1) a complete design of the salt SURF repository including inventory, density and waste package design details; (2) probalistic failure rate data on containment integrity of the SURF waste package; (3) probabilistic failure rate data on the monitoring system components

  20. SURF IA Conflict Detection and Resolution Algorithm Evaluation

    Science.gov (United States)

    Jones, Denise R.; Chartrand, Ryan C.; Wilson, Sara R.; Commo, Sean A.; Barker, Glover D.

    2012-01-01

    The Enhanced Traffic Situational Awareness on the Airport Surface with Indications and Alerts (SURF IA) algorithm was evaluated in a fast-time batch simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center. SURF IA is designed to increase flight crew situation awareness of the runway environment and facilitate an appropriate and timely response to potential conflict situations. The purpose of the study was to evaluate the performance of the SURF IA algorithm under various runway scenarios, multiple levels of conflict detection and resolution (CD&R) system equipage, and various levels of horizontal position accuracy. This paper gives an overview of the SURF IA concept, simulation study, and results. Runway incursions are a serious aviation safety hazard. As such, the FAA is committed to reducing the severity, number, and rate of runway incursions by implementing a combination of guidance, education, outreach, training, technology, infrastructure, and risk identification and mitigation initiatives [1]. Progress has been made in reducing the number of serious incursions - from a high of 67 in Fiscal Year (FY) 2000 to 6 in FY2010. However, the rate of all incursions has risen steadily over recent years - from a rate of 12.3 incursions per million operations in FY2005 to a rate of 18.9 incursions per million operations in FY2010 [1, 2]. The National Transportation Safety Board (NTSB) also considers runway incursions to be a serious aviation safety hazard, listing runway incursion prevention as one of their most wanted transportation safety improvements [3]. The NTSB recommends that immediate warning of probable collisions/incursions be given directly to flight crews in the cockpit [4].

  1. Fatal accidents due to train surfing in Berlin.

    Science.gov (United States)

    Strauch, H; Wirth, I; Geserick, G

    1998-06-08

    This study was undertaken for the purpose of analysing under the aspect of legal medicine, fatal accidents due to train surfing in the local transport system of Berlin (S-Bahn and underground). The period of investigation was from 1989 through 1995, with 41 train surfing accidents, among them 18 with fatal outcome. Evaluation included those 14 deaths which were forensically autopsied. It was based on autopsy records of Berlin-based university institutes (Humboldt University and Free University) as well as the Brandenburg State Institute of Legal Medicine. Also used were data obtained from the Berlin Transport Police Record. The casualties were aged between 13 and 25 years, most of them between 16 and 20. The male-female gender ratio was 13:1. Accidents occurred above all in the warmer season of the year, most of them between 20:00 h and midnight. More than 50% of all cases were affected by alcohol, but centrally acting medicaments or other addictive drugs were not noticed at all. Most of the fatal accidents occurred to users of the Berlin S-Bahn network. Older train models were the preferred surfing objects due to their structural peculiarities. Collision with close-to-track obstacles and slipping from the train proved to be the major sources of danger. An analysis of injuries revealed polytraumatisation but for one exception, with craniocerebral injuries being the most common and severest events. The longest survival time amounted to 24 h. As the psychosocial causes of high-risk behaviour of adolescents will hardly be controllable, withdrawal of technical, that is structural design possibilities appears to be the most important approach to prevention of accidents in the future. This demand is met by the new series of the Berlin S-Bahn. The model of the old series, suitable for surfing, still accounts for about 10% of the rolling stock and is to be decommissioned in 1998.

  2. 'CouchSurfing' : explorations in cosmopolitanism, trust, and resistance

    OpenAIRE

    Shapiro, Josh D.

    2012-01-01

    This dissertation is based on qualitative and quantitative research conducted via a case study of CouchSurfing.org, a hybrid online/offline hospitality exchange network that enables travelers to locate locals who offer them free accommodation. Chapter one begins with a statistical analysis of CouchSurfers to determine if they hold a cosmopolitan orientation. My analysis incorporates nationally representative samples from 21 different countries, over 1400 CouchSurfers, and 74,000 respondents t...

  3. Selected programs at the new SURF III electron storage ring

    International Nuclear Information System (INIS)

    Furst, Mitchell L.; Arp, Uwe; Cauchon, Gilles P.; Graves, Rossie M.; Hamilton, Andrew D.; Hughey, Lanny R.; Lucatorto, Thomas B.; Tarrio, Charles

    2000-01-01

    The conversion of the electron storage ring at NIST (the National Institute of Standards and Technology) to SURF III (the Synchrotron Ultraviolet Radiation Facility) has resulted in a significant improvement to the azimuthal uniformity of the magnetic field as well as the capability for operating at higher beam energies. Measurements of magnetic field strength revealed azimuthal uniformity of better than ±0.05% at field strengths equivalent to operating energies of 52 MeV to 417 MeV. Initial operation is restricted to energies up to 331 MeV due to temporary limitations in the rf transmission system. Even at 331 MeV there is already a significant extension of the usable short wavelength range of the synchrotron radiation as compared to the range available at the 284 MeV operating energy of SURF II. These and other improvements have a major impact on SURF programs including: the Nanodetector, a conversion microscope which is a prototype real-time imaging system for EUV (extreme ultraviolet) lithography; the Spectrometer Calibration Beamline, used for high-accuracy absolute calibration of spectrometers; and the National EUV Reflectometry Facility, used to measure optical constants of thin-film multilayer optics

  4. NBS SURF 11: A small versatile synchrotron light source

    International Nuclear Information System (INIS)

    Rakowsky, G.

    1981-01-01

    Synchrotron radiation sources do not have to be large multi-megadollar installations. SURF II is based on a compact electron storage ring with a radius of only 0.84 m, an operating energy of 250 MeV, and useful light output down to 5 nm. Small beam size, high brightness and wide-angle light ports give SURF II unique capabilities. Presently five beamlines are instrumented and operational, supporting experiments in atomic and molecular physics, surface science and materials studies, as well as providing optical calibration services. Nearing completion is a large facility for calibrating optical instruments, especially those intended for space flight. The capability of determining the absolute light flux emitted by SURF II has recently been improved and is now operational. The technique employs ultralinear silicon photodiodes to detect and count individual electrons in the stored beam. Other user conveniences include close access to the machine, flexible scheduling and close interaction with the operations staff. The machine's simplicity contributes to reliability and a high ratio of beamtime to downtime

  5. The Role of Core Stability in Surfing : According to a Delphi Panel

    OpenAIRE

    Airaksinen, Liisa

    2013-01-01

    Core stability has been widely discussed in physiotherapy. Yet, no consensus has been reached on the anatomy, tasks or benefits of core stability. Good core stability has been proven to decrease low-back pain and prevent specifically female athletes’ from getting lower extremity injuries. Surfing has become an extremely popular sport. As a surfer I am intrigued to know what the exact role of core stability in surfing is. There are a limited number of studies on surfing and most of...

  6. Mercury distribution characteristics in primary manganese smelting plants.

    Science.gov (United States)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-08-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1-99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. Copyright © 2017. Published by Elsevier Ltd.

  7. Status of rainbow smelt in the U.S. waters of Lake Ontario, 2013

    Science.gov (United States)

    Weidel, Brian C.; Connerton, Michael J.

    2014-01-01

    Rainbow Smelt Osmerus mordax are the second most abundant pelagic prey fish in Lake Ontario after Alewife Alosa psuedoharengus. The 2013, USGS/NYSDEC bottom trawl assessment indicated the abundance of Lake Ontario age-1 and older Rainbow Smelt decreased by 69% relative to 2012. Length frequency-based age analysis indicated that age-1 Rainbow Smelt constituted approximately 50% of the population, which is similar to recent trends where the proportion of age-1 has ranged from 95% to 42% of the population. While they constituted approximately half of the catch, the overall abundance index for age 1 was one of the lowest observed in the time series, potentially a result of cannibalism from the previous year class. Combined data from all bottom trawl assessments along the southern shore and eastern basin indicate the proportion of the fish community that is Rainbow Smelt has declined over the past 30 years. In 2013 the proportion of the pelagic fish catch (only pelagic species) that was Rainbow Smelt was the second lowest in the time series at 3.1%. Community diversity indices, based on bottom trawl catches, indicate that Lake Ontario fish community diversity, as assessed by bottom trawls, has sharply declined over the past 36 years and in 2013 the index was the lowest value in the time series. Much of this community diversity decline is driven by changes in the pelagic fish community and dominance of Alewife.

  8. Reaction Mechanism and Distribution Behavior of Arsenic in the Bottom Blown Copper Smelting Process

    Directory of Open Access Journals (Sweden)

    Qinmeng Wang

    2017-08-01

    Full Text Available The control of arsenic, a toxic and carcinogenic element, is an important issue for all copper smelters. In this work, the reaction mechanism and distribution behavior of arsenic in the bottom blown copper smelting process (SKS process were investigated and compared to the flash smelting process. There are obvious differences of arsenic distribution in the SKS process and flash process, resulting from the differences of oxygen potentials, volatilizations, smelting temperatures, reaction intensities, and mass transfer processes. Under stable production conditions, the distributions of arsenic among matte, slag, and gas phases are 6%, 12%, and 82%, respectively. Less arsenic is reported in the gas phase with the flash process than with the SKS process. The main arsenic species in gas phase are AsS (g, AsO (g, and As2 (g. Arsenic exists in the slag predominantly as As2O3 (l, and in matte as As (l. High matte grade is harmful to the elimination of arsenic to gas. The changing of Fe/SiO2 has slight effects on the distributions of arsenic. In order to enhance the removal of arsenic from the SKS smelting system to the gas phase, low oxygen concentration, low ratios of oxygen/ore, and low matte grade should be chosen. In the SKS smelting process, no dust is recycled, and almost all dust is collected and further treated to eliminate arsenic and recover valuable metals by other process streams.

  9. Mathematical model of whole-process calculation for bottom-blowing copper smelting

    Science.gov (United States)

    Li, Ming-zhou; Zhou, Jie-min; Tong, Chang-ren; Zhang, Wen-hai; Li, He-song

    2017-11-01

    The distribution law of materials in smelting products is key to cost accounting and contaminant control. Regardless, the distribution law is difficult to determine quickly and accurately by mere sampling and analysis. Mathematical models for material and heat balance in bottom-blowing smelting, converting, anode furnace refining, and electrolytic refining were established based on the principles of material (element) conservation, energy conservation, and control index constraint in copper bottom-blowing smelting. Simulation of the entire process of bottom-blowing copper smelting was established using a self-developed MetCal software platform. A whole-process simulation for an enterprise in China was then conducted. Results indicated that the quantity and composition information of unknown materials, as well as heat balance information, can be quickly calculated using the model. Comparison of production data revealed that the model can basically reflect the distribution law of the materials in bottom-blowing copper smelting. This finding provides theoretical guidance for mastering the performance of the entire process.

  10. E-based Humanities and E-humanities on a SURF platform

    NARCIS (Netherlands)

    Kircz, J.G.

    2004-01-01

    As of 2003, SURF enables three platforms: ICT and Research, Education, and Organisation. Within these programmes, SURF has funds available to promote ICT innovations. Innovation is not an easy notion to explain. Too often we encounter new wine in old bottles and changes in vocabulary frequently

  11. Parents' Perspectives on Surf Therapy for Children with Disabilities

    Science.gov (United States)

    Moore, Adam M.; Clapham, Emily D.; Deeney, Theresa A.

    2018-01-01

    This qualitative study was designed to understand parents' perceptions of their children's participation in an inclusive surf therapy programme in the United States. Ten parents and one caregiver were interviewed about theirs and their children's experience in the surf programme. Parent discussions centred on the child, parent/caregiver,…

  12. Social Networking Sites' Influence on Travelers' Authentic Experience a Case Study of Couch Surfing

    Science.gov (United States)

    Liu, Xiao

    2013-01-01

    This study explored travelers' experiences in the era of network hospitality 2.0 using CouchSurfing.org as a case study. The following research questions guided this study: 1) what experience does CouchSurfing create for travelers before, during and after their travel? 2) how does couch surfers' experience relate to authenticity in context of…

  13. PENGEMBANGAN SELANCAR (SURFING MELALUI PEMBERDAYAAN MASYARAKAT (COMMUNITY BASED DEVELOPMENT DI KAWASAN WISATA PANTAI KUTA, KABUPATEN BADUNG

    Directory of Open Access Journals (Sweden)

    N. L. Henny Andayani

    2014-05-01

    Full Text Available Kuta merupakan salah satu kawasan wisata di Kabupaten Badung yang dilengkapi dengan beragam fasilitas wisata, seperti restoran, bar, hotel, laundry, dan money changer. Keberadaan kawasan wisata Kuta tidak terlepas dari atraksi wisata utama berupa keindahan pantai dengan pasir putihnya. Beragam aktifitas wisata seperti berjemur, dan surfing, dapat dilakukan di Kuta. Penelitian ini bertujuan untuk (1 Mengetahui keterlibatan dan peran serta masyarakat local dalam pengembangan potensi wisata selancar (surfing selama ini (2 Mengetahui strategi pengembangan aktifitas wisata selancar (surfing sebagai daya tarik wisata baharí/tirta di Bali dengan memberdayakan masyarakat lokal. Pendekatan yang dilakukan dalam penelitian ini adalah pendekatan kualitatif dengan menggunakan teknik pengumpulan data, wawancara, observasi dan studi dokumentasi. Data yang diperoleh selanjutnya dianalisis dengan matriks internal eksternal dan dilanjutkan dengan analisis SWOT. Hasil penelitian menunjukkan bahwa peran serta dan keikutsertaan masyarakat lokal dalam pengembangan selancar (surfing di kawasan wisata Kuta masih sedikit. Para pelaku dan investor mayoritas berasal dari luar wilayah Kuta. Berdasarkan analisis SWOT didapatkan strategi alternatif yang perlu dikembangkan di Kuta, antara lain: pengembangan surfing berbasis masyarakat lokal di kawasan Kuta, pengembangan usaha jasa pelayanan surfing yang dimiliki dan dikelola oleh masyarakat lokal, strategi peningkatan keamanan dan kenyamanan bagi wisatawan yang melakukan kegiatan surfing di Kawasan Kuta, dan strategi pengembangan kelembagaan terhadap kegiatan surfing.

  14. Comparison of risks due to HLW and SURF repositories in bedded salt

    International Nuclear Information System (INIS)

    Chu, M.S.Y.; Ortiz, N.R.; Wahi, K.K.

    1983-01-01

    A methodology was developed for use in the analysis of risks from geologic disposal of nuclear wastes. This methodology is applied to two conceptual nuclear waste repositories in bedded salt containing High-Level Waste (HLW) and Spent Un-Reprocessed Fuel (SURF), respectively. A comparison of the risk estimated from the HLW and SURF repositories is presented

  15. Cultural boundary surfing in mental health nursing: a creative narration.

    Science.gov (United States)

    Kidd, Jacquie

    2010-01-01

    In the mental health context, nurses navigate multifaceted boundaries every day in an effort to develop and maintain the therapeutic relationship; an endeavour that is breathtaking in its complexity. In this paper, I adopt an unconventional form of writing to explore the individual nature of cultural boundaries, and uncover hidden messages that impact on our efforts to build connections across cultures and ethnicities in mental health settings. Presented as a play, the conversation between protagonists explores cultural competence alongside the notion of 'discovery', and the potential of the Tidal Model to provide a vehicle for successful cultural boundary surfing.

  16. Smelting reduction of MgO in molten slag by liquid ferrosilicon

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Q.; Gao, J.; Chen, X.; Wei, X.

    2016-10-01

    The smelting reduction of magnesium oxide was researched in this paper. The effect of molten slag composition and reduction temperature on percent reduction of magnesium oxide were discussed, and kinetics of smelting reduction of magnesium oxide in molten slag was studied. The results showed that the reduction extent of magnesium oxide increased by increasing either one of the following factors: the initial mass ratio of Al{sub 2}O{sub 3}/SiO{sub 2}, the addition of CaF{sub 2}, the initial molar ratio of Si/2MgO, and reaction temperature. The overall smelting reduction was controlled by mass transfer in slag with an apparent activation energy 586 kJ mol{sup -}1. (Author)

  17. Development and Application of SKSSIM Simulation Software for the Oxygen Bottom Blown Copper Smelting Process

    Directory of Open Access Journals (Sweden)

    Qinmeng Wang

    2017-10-01

    Full Text Available The oxygen bottom blown copper smelting process (SKS process is a newly developed intense smelting process, which has been widely applied to copper production in China. A multiphase equilibrium model for the SKS process was established based on its mechanism characteristics and the principle of Gibbs energy minimization, and an efficient simulation software—SKSSIM (SKS Simulation—was developed based on the model. Industrial data from the SKS process were used to compare with the calculated data from the SKSSIM software. The calculated data on the compositions of slag and matte as well as the distribution ratios of minor elements (such as Pb, Zn, As, Sb and Bi among the slags, mattes and off-gases were in good agreement with the actual plant data. Accordingly, the SKSSIM simulation software has the potentail to be used for the prediction of smelting production and for optimizing the operating parameters of the SKS process.

  18. Energy Consumption in Copper Smelting: A New Asian Horse in the Race

    Science.gov (United States)

    Coursol, P.; Mackey, P. J.; Kapusta, J. P. T.; Valencia, N. Cardona

    2015-05-01

    After a marked improvement in energy consumption in copper smelting during the past few decades, technology development has been slowing down in the Americas and in Europe. Innovation, however, is still required to further reduce energy consumption while complying with stringent environmental regulations. The bottom blowing smelting technology being developed in China shows success and promise. The general configuration of the bath smelting vessel, the design of high-pressure injectors, and the concentrate addition system are described and discussed in this article with respect to those used in other technologies. The bottom blowing technology is shown to be operating at a temperature in the range of 1160-1180°C, which is the lowest reported temperature range for a modern copper smelting process. In this article, it is suggested that top feeding of filter cake concentrate, which is also used in other technologies, has a positive effect in reducing the oxidation potential of the slag ( p(O2)) while increasing the FeS solubility in slag. This reduction in p(O2) lowers the magnetite liquidus of the slag, while the increased solubility of FeS in slag helps toward reaching very low copper levels in flotation slag tailings. The application of high-pressure injectors allows for the use of high levels of oxygen enrichment with no requirements for punching. Using a standard modeling approach from the authors' previous studies, this article discusses these aspects and compares the energy consumption of the bottom blowing technology with that of other leading flash and bath smelting technologies, namely: flash smelting, Noranda/Teniente Converter, TSL (Isasmelt [Glencore Technology Pty. Ltd., Brisbane, Queensland, Australia]/Outotec), and the Mitsubishi Process (Mitsubishi Materials Corporation, Tokyo, Japan).

  19. Habitat use by larval fishes in a temperate South African surf zone

    Science.gov (United States)

    Watt-Pringle, Peter; Strydom, Nadine A.

    2003-12-01

    Larval fishes were sampled in the Kwaaihoek surf zone on the south east coast of South Africa. On six occasions between February and May 2002, larval fishes were collected in two habitat types identified in the inner surf zone using a modified beach-seine net. The surf zone habitats were classified as either sheltered trough areas or adjacent exposed surf areas. Temperature, depth and current measurements were taken at all sites. Trough habitats consisted of a depression in surf topography characterised by reduced current velocities and greater average depth than adjacent surf areas. In total, 325 larval fishes were collected. Of these, 229 were collected in trough and 96 in surf habitats. At least 22 families and 37 species were represented in the catch. Dominant families were the Mugilidae, Sparidae, Atherinidae, and Engraulidae. Dominant species included Liza tricuspidens and Liza richardsonii (Mugilidae), Rhabdosargus holubi and Sarpa salpa (Sparidae), Atherina breviceps (Atherinidae) and Engraulis japonicus (Engraulide). Mean CPUE of postflexion larvae of estuary-dependent species was significantly greater in trough areas. The proportion of postflexion larval fishes in trough habitat was significantly greater than that of preflexion stages, a result that was not apparent in surf habitat sampled. CPUE of postflexion larvae of estuary-dependent fishes was negatively correlated with current magnitude and positively correlated with habitat depth. Mean body length of larval fishes was significantly greater in trough than in surf habitats. These results provide evidence that the CPUE of postflexion larvae of estuary-dependent fishes is higher in trough habitat in the surf zone and this may be indicative of active habitat selection for areas of reduced current velocity/wave action. The implications of this behaviour for estuarine recruitment processes are discussed.

  20. A study on the smelting of electrolytically reduced spent fuel by using surrogates

    International Nuclear Information System (INIS)

    Hur, Jin-Mok; Jeong, Myoung-Soo; Cho, Soo-Haeng; Seo, Chung-Seok; Park, Seong-Won

    2005-01-01

    A smelting as a part of the advanced spent fuel conditioning process (ACP) was studied by using surrogate materials. Residual salts including LiCl-Li 2 O were successfully separated from the metal components by an evaporation at 950degC. The melting of the metal was characterized, especially by considering the oxidation of the fine metal particles. The operation procedure of the smelting was set up as 1) removal of residual salts, 2) melting of the metal powder, and 3) a solidification of the melted mass to an ingot. (author)

  1. Notes from the Field: Acute Mercury Poisoning After Home Gold and Silver Smelting--Iowa, 2014.

    Science.gov (United States)

    Koirala, Samir; Leinenkugel, Kathy

    2015-12-18

    In March 2014, a man, aged 59 years, who lived alone and had been using different smelting techniques viewed on the Internet to recover gold and silver from computer components, was evaluated at a local emergency department for shortness of breath, tremors, anorexia, and generalized weakness. During the smelting processes, he had used hydrogen peroxide, nitric acid, muriatic acid, and sulfuric acid purchased from local stores or Internet retailers. For protection, he wore a military gas mask of unknown type. The mask was used with filter cartridges, but their effectiveness against chemical fumes was not known.

  2. Respiratory Problems Associated with Surfing in Coastal Waters.

    Science.gov (United States)

    O'Halloran, Chris; Silver, Mary W; Lahiff, Maureen; Colford, John

    2017-03-01

    A pilot project was conducted to examine the health status and possible adverse health effects associated with seawater exposure (microbial water-quality indicators and phytoplankton abundance and their toxins) of surfers in Monterey Bay, Central California coastal waters. Forty-eight surfers enrolled in the study and completed an initial health background survey and weekly health surveys online using Survey Monkey. Descriptive statistics and generalized estimating equation, a regression technique, were used to identify longitudinal and correlated results. The surfers were predominately Caucasian, male, and physically active. They surfed approximately 4 h a week. Their average age was 34 years. The data indicated that the surfers were generally "healthy," with a low prevalence of diabetes, high cholesterol, and hypertension. Their most common health problems were allergies and asthma. During the study, 10% of the surfers reported gastrointestinal symptoms and 29% reported upper respiratory symptoms. This study suggests surfers were significantly more likely to report upper respiratory symptoms when they had a history of allergies, housemates with upper respiratory symptoms, and/or a history of previous adverse health symptoms while surfing during a "red tide" (an event often associated with the presence of phytoplankton toxins). Additionally, female surfers reported upper respiratory symptoms more than males.

  3. Evaluation of a 3% surf solution (surf field mastitis test) for the diagnosis of subclinical bovine and bubaline mastitis.

    Science.gov (United States)

    Muhammad, Ghulam; Naureen, Abeera; Asi, Muhammad Nadeem; Saqib, Muhammad; Fazal-ur-Rehman

    2010-03-01

    To evaluate a 3% solution of household detergent viz., Surf Excel (Surf field mastitis test, SFMT) vis-à-vis California mastitis test (CMT), Whiteside test (WST), somatic cell counts (SCC; cut off limit = 5 x 10(5) cells per millilitre) and bacteriological cultures for the detection of subclinical mastitis in quarter foremilk samples (n=800) of dairy cows and buffaloes. Culture and SCC were used as gold standards. All tests were evaluated parallel and serial patterns. The sensitivities of SFMT, SCC, culture, CMT and WST in parallel testing were 72.82, 81.55, 87.38, 75.73 and 54.37%, respectively in cows, while 66.22, 79.73, 82.43, 70.27 and 50.00, respectively in buffaloes. SFMT was significantly (pnegative predictive values of SFMT (93.50 in cow; 96.35 in buffaloes) differed non-significantly from that of CMT (94.02 in cow; 96.15 in buffaloes). The kappa index between the tests was moderate to perfect both in parallel (0.54 to >0.80) and serial (0.58 to >0.8) testing. On the basis of closely similar diagnostic efficiency of SFMT to CMT in terms of sensitivity, specificity, predictive values and kappa index together with inexpensive and ready availability of SFMT reagent, it tempting to suggest that SFMT can be use as a cheaper, user-friendly alternative animal-side subclinical mastitis diagnostic test in poor countries.

  4. Data on cytochrome c oxidase assembly in mice and human fibroblasts or tissues induced by SURF1 defect

    Directory of Open Access Journals (Sweden)

    Nikola Kovářová

    2016-06-01

    Full Text Available This paper describes data related to a research article entitled “Tissue- and species-specific differences in cytochrome c oxidase assembly induced by SURF1 defects” [1]. This paper includes data of the quantitative analysis of individual forms of respiratory chain complexes I, III and IV present in SURF1 knockout (SURF1−/− and control (SURF1+/+ mouse fibroblasts and tissues and in fibroblasts of human control and patients with SURF1 gene mutation. Also it includes data demonstrating response of complex IV, cytochrome c oxidase (COX, to reversible inhibition of mitochondrial translation in SURF1−/− mouse and SURF1 patient fibroblast cell lines.

  5. Injuries resulting from car surfing--United States, 1990-2008.

    Science.gov (United States)

    2008-10-17

    "Car surfing" is a term introduced in the mid-1980s to describe a thrill-seeking activity that involves riding on the exterior of a moving motor vehicle while it is being driven by another person. Although reports of car-surfing injuries have been published in the United States, no study to date has analyzed these events from a national perspective. Because traditional public health datasets do not collect morbidity or mortality data on this practice, CDC searched U.S. newspaper reports to provide an initial characterization of car-surfing injuries on a national scale. That analysis identified 58 reports of car-surfing deaths and 41 reports of nonfatal injury from 1990 through August 2008. Most reports of car-surfing injuries came from newspapers in the Midwest and South (75%), and most of the injuries were among males (70%) and persons aged 15-19 years (69%). The first identified newspaper reports about car-surfing injuries were published in the early 1990s, and new reports have been published every year since then. Parents and teens should be aware of the potentially lethal consequences of car surfing, which can occur even at low vehicle speeds, sometimes resulting from unanticipated movements of the vehicle, such as swerving or braking.

  6. An analytical model for non-conservative pollutants mixing in the surf zone.

    Science.gov (United States)

    Ki, Seo Jin; Hwang, Jin Hwan; Kang, Joo-Hyon; Kim, Joon Ha

    2009-01-01

    Accurate simulation of the surf zone is a prerequisite to improve beach management as well as to understand the fundamentals of fate and transport of contaminants. In the present study, a diagnostic model modified from a classic solute model is provided to illuminate non-conservative pollutants behavior in the surf zone. To readily understand controlling processes in the surf zone, a new dimensionless quantity is employed with index of kappa number (K, a ratio of inactivation rate to transport rate of microbial pollutant in the surf zone), which was then evaluated under different environmental frames during a week simulation period. The sensitivity analysis showed that hydrodynamics and concentration gradients in the surf zone mostly depend on n (number of rip currents), indicating that n should be carefully adjusted in the model. The simulation results reveal, furthermore, that large deviation typically occurs in the daytime, signifying inactivation of fecal indicator bacteria is the main process to control surf zone water quality during the day. Overall, the analytical model shows a good agreement between predicted and synthetic data (R(2) = 0.51 and 0.67 for FC and ENT, respectively) for the simulated period, amplifying its potential use in the surf zone modelling. It is recommended that when the dimensionless index is much larger than 0.5, the present modified model can predict better than the conventional model, but if index is smaller than 0.5, the conventional model is more efficient with respect to time and cost.

  7. Reductions in Sprint Paddling Ability and Countermovement Jump Performance After Surfing Training.

    Science.gov (United States)

    Secomb, Josh L; Sheppard, Jeremy M; Dascombe, Ben J

    2015-07-01

    The present study aimed to determine whether any meaningful change in a surfer's sprint paddling ability and countermovement jump (CMJ) performance developed after a 2-hour surfing training session and also whether any physical demands of the surfing session were related to the resultant changes in the capacities. Fifteen competitive male surfing athletes (age, 22.1 ± 3.9 years; height, 175.4 ± 6.4 cm; body mass, 72.5 ± 7.7 kg) performed a 2-hour surfing training session, with 15-m sprint paddle and CMJ trials performed both before and after the surfing session. Pre- to posttesting measures were analyzed using magnitude-based inferences. Likely declines were observed in the velocity achieved at the 5-, 10-, and 15-m splits of the 15-m sprint paddle, as well as peak velocity. Similarly, likely declines were calculated for CMJ peak force, relative peak force, and jump height. Furthermore, large correlations were calculated between presurfing session peak velocity and the change in 5, 10, 15 m, and peak velocity of the 15-m sprint paddle and total distance covered, wave riding bouts, and success rate. Surfing athletes and coaches may need to consider implementing shorter duration training sessions to reduce the decline in sprint paddling ability and CMJ performance. Furthermore, surfing athletes should possess highly developed sprint paddling ability because this may allow them to undertake a greater workload and catch more waves, which will increase the opportunity for technical refinement of maneuvers and skill acquisition.

  8. Global assessment of surfing conditions: seasonal, interannual and long-term variability

    Science.gov (United States)

    Espejo, A.; Losada, I.; Mendez, F.

    2012-12-01

    International surfing destinations owe a great debt to specific combinations of wind-wave, thermal conditions and local bathymetry. As surf quality depends on a vast number of geophysical variables, a multivariable standardized index on the basis of expert judgment is proposed to analyze surf resource in a worldwide domain. Data needed is obtained by combining several datasets (reanalyses): 60-year satellite-calibrated spectral wave hindcast (GOW, WaveWatchIII), wind fields from NCEP/NCAR, global sea surface temperature from ERSST.v3b, and global tides from TPXO7.1. A summary of the global surf resource is presented, which highlights the high degree of variability in surfable events. According to general atmospheric circulation, results show that west facing low to middle latitude coasts are more suitable for surfing, especially those in Southern Hemisphere. Month to month analysis reveals strong seasonal changes in the occurrence of surfable events, enhancing those in North Atlantic or North Pacific. Interannual variability is investigated by comparing occurrence values with global and regional climate patterns showing a great influence at both, global and regional scales. Analysis of long term trends shows an increase in the probability of surfable events over the west facing coasts on the planet (i.e. + 30 hours/year in California). The resulting maps provide useful information for surfers and surf related stakeholders, coastal planning, education, and basic research.; Figure 1. Global distribution of medium quality (a) and high quality surf conditions probability (b).

  9. Migration of diadromous and landlocked smelt populations studies by otolith geochemistry

    NARCIS (Netherlands)

    Phung, A.T.; Tulp, I.Y.M.; Baeyens, W.; Elskens, M.; Leermakers, M.; Gao, Y.

    2015-01-01

    Laser ablation inductively coupled mass spectrometry (LA-ICPMS) was used to determine Sr and Ba profiles along the growth axis of otholiths of European smelt caught in the Wadden Sea, the IJsselmeer and the Markermeer and to investigate the migration behaviour of the fish between the freshwater

  10. RISK ASSESSMENT AND REMEDIATION OF SOILS CONTAMINATED BY MINING AND SMELTING OF LEAD, ZINC AND CADMIUM

    Science.gov (United States)

    Mining nd smelting of Pb, Zn and Cd ores have caused widespread soil contamination in many countries. In locations with severe soil contamination, and strongly acidic soil or mine waste, ecosystems are devastated. Research has shown that An phytotoxicity, Pb-induced phosphate def...

  11. Reductive-sulfurizing smelting treatment of smelter slag for copper and cobalt recovery

    Directory of Open Access Journals (Sweden)

    Li Y.

    2018-01-01

    Full Text Available Recovery of copper and cobalt from smelter slag using reductive-sulfurizing smelting method was performed in this study. The effects of reductive agent (coke, sulfurizing agent (pyrite, slag modifier (CaO and smelting temperature and duration on the extractive efficiencies of Cu, Co and Fe were discussed. The phase compositions and microstructure of the materials, copper-cobalt matte and cleaned slag were determined. The results showed that copper and cobalt contents in cleaned slag could decrease averagely to 0.18% and 0.071% respectively after cleaning. 91.99% Cu and 92.94% Co and less than 38.73% Fe were recovered from the smelter slag under the optimum conditions: 6 wt.% coke, 20 wt.% pyrite and 6 wt.% CaO addition to the smelter slag, smelting temperature of 1350°C and smelting duration of 3h. The addition of CaO can increase the selectivity of Co recovery. The cleaning products were characterized by XRD and SEM-EDS analysis. The results showed that the main phases of copper-cobalt matte were iron sulfide (FeS, geerite (Cu8S5, iron cobalt sulfide (Fe0.92Co0.08S and Fe-Cu-Co alloy. The cleaned slag mainly comprised fayalite (Fe2SiO4, hedenbergite (CaFe(Si2O6 and magnetite (Fe3O4.

  12. Effects of a reducer type on copper flash smelting slag decopperisation

    Directory of Open Access Journals (Sweden)

    B. Oleksiak

    2015-01-01

    Full Text Available In the paper, results of investigations on coke dust, anthracite dust and coal flotation concentrate application in the technology of copper flash smelting slag processing are presented. The results show that the selected reducers can be used as substitutes for the conventional coke.

  13. [Limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou].

    Science.gov (United States)

    Lin, Wen-Jie; Xiao, Tang-Fu; Ao, Zi-Qiang; Xing, Jun; Ma, Huan-Cheng; Hu, Ting-Xing

    2007-03-01

    With indigenous zinc smelting waste residue, contaminated soil and background soil as test substrates, a pot experiment was conducted to study the growth characteristics of Lolium perenne and Trifolium pretense on these substrates. The results showed that the major limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou were the salt-alkali stress and the lower contents of organic matter, total N, available N and total K. The heavy metals in waste residue had a high concentration, but their available forms only occupied a small proportion, with low toxicity to plant but having potential harmful risk. Contaminated soil had lower concentrations of heavy metals than waste residue, but its contained heavy metals were more in available form. The constraints of revegetation on contaminated soil were the toxicity of heavy metals and the low contents of available P and K. Mixing contaminated soil with zinc smelting waste residue could be one of the effective approaches for the substrate amendment in indigenous zinc smelting areas.

  14. Distribution and health risk assessment to heavy metals near smelting and mining areas of Hezhang, China.

    Science.gov (United States)

    Briki, Meryem; Zhu, Yi; Gao, Yang; Shao, Mengmeng; Ding, Huaijian; Ji, Hongbing

    2017-08-19

    Mining and smelting areas in Hezhang have generated a large amount of heavy metals into the environment. For that cause, an evaluative study on human exposure to heavy metals including Co, Ni, Cu, Zn, Cr, As, Cd, Pb, Sb, Bi, Be, and Hg in hair and urine was conducted for their concentrations and correlations. Daily exposure and non-carcinogenic and carcinogenic risk were estimated. Sixty-eight scalp hair and 66 urine samples were taken from participants of different ages (6-17, 18-40, 41-60, and ≥ 65 years) living in the vicinity of an agricultural soil near mine and smelting areas. The results compared to the earlier studies showed an elevated concentration of Pb, Be, Bi, Co, Cr, Ni, Sb, and Zn in hair and urine. These heavy metals were more elevated in mining than in smelting. Considering gender differences, females were likely to be more affected than male. By investigating age differences in this area, high heavy metal concentrations in male's hair and urine existed in age of 18-40 and ≥ 66, respectively. However, females did not present homogeneous age distribution. Hair and urine showed a different distribution of heavy metals in different age and gender. In some cases, significant correlation was found between heavy metals in hair and urine (P > 0.05 and P > 0.01) in mining area. The estimated average daily intake of heavy metals in vegetables showed a great contribution compared to the soil and water. Non-carcinogenic and carcinogenic risk values of total pathways in mining and smelting areas were higher than 1 and exceeded the acceptable levels. Thus, the obtained data might be useful for further studies. They can serve as a basis of comparison and assessing the effect of simultaneous exposure from heavy metals in mining and smelting areas, and potential health risks from exposure to heavy metals in vegetables need more consideration.

  15. Interactions between hatch dates, growth rates, and mortality of Age-0 native Rainbow Smelt and nonnative Alewife in Lake Champlain

    Science.gov (United States)

    Parrish, Donna; Simonin, Paul W.; Rudstam, Lars G.; Pientka, Bernard; Sullivan, Patrick J.

    2016-01-01

    Timing of hatch in fish populations can be critical for first-year survival and, therefore, year-class strength and subsequent species interactions. We compared hatch timing, growth rates, and subsequent mortality of age-0 Rainbow Smelt Osmerus mordax and Alewife Alosa pseudoharengus, two common open-water fish species of northern North America. In our study site, Lake Champlain, Rainbow Smelt hatched (beginning May 26) almost a month earlier than Alewives (June 20). Abundance in the sampling area was highest in July for age-0 Rainbow Smelt and August for age-0 Alewives. Late-hatching individuals of both species grew faster than those hatching earlier (0.6 mm/d versus 0.4 for Rainbow Smelt; 0.7 mm/d versus 0.6 for Alewives). Mean mortality rate during the first 45 d of life was 3.4%/d for age-0 Rainbow Smelt and was 5.5%/d for age-0 Alewives. Alewife mortality rates did not differ with hatch timing but daily mortality rates of Rainbow Smelt were highest for early-hatching fish. Cannibalism is probably the primary mortality source for age-0 Rainbow Smelt in this lake. Therefore, hatching earlier may not be advantageous because the overlap of adult and age-0 Rainbow Smelt is highest earlier in the season. However, Alewives, first documented in Lake Champlain in 2003, may increase the mortality of age-0 Rainbow Smelt in the summer, which should favor selection for earlier hatching.

  16. SurfCut: Surfaces of Minimal Paths From Topological Structures

    KAUST Repository

    Algarni, Marei Saeed Mohammed

    2018-03-05

    We present SurfCut, an algorithm for extracting a smooth, simple surface with an unknown 3D curve boundary from a noisy image and a seed point. Our method is built on the novel observation that certain ridge curves of a function defined on a front propagated using the Fast Marching algorithm lie on the surface. Our method extracts and cuts these ridges to form the surface boundary. Our surface extraction algorithm is built on the novel observation that the surface lies in a valley of the distance from Fast Marching. We show that the resulting surface is a collection of minimal paths. Using the framework of cubical complexes and Morse theory, we design algorithms to extract these critical structures robustly. Experiments on three 3D datasets show the robustness of our method, and that it achieves higher accuracy with lower computational cost than state-of-the-art.

  17. SurfCut: Surfaces of Minimal Paths From Topological Structures

    KAUST Repository

    Algarni, Marei Saeed Mohammed

    2017-04-30

    We present SurfCut, an algorithm for extracting a smooth, simple surface with an unknown 3D curve boundary from a noisy 3D image and a seed point. Our method is built on the novel observation that certain ridge curves of a function defined on a front propagated using the Fast Marching algorithm lie on the surface. Our method extracts and cuts these ridges to form the surface boundary. Our surface extraction algorithm is built on the novel observation that the surface lies in a valley of the distance from Fast Marching. We show that the resulting surface is a collection of minimal paths. Using the framework of cubical complexes and Morse theory, we design algorithms to extract these critical structures robustly. Experiments on three 3D datasets show the robustness of our method, and that it achieves higher accuracy with lower computational cost than state-of-the-art.

  18. SurfCut: Free-Boundary Surface Extraction

    KAUST Repository

    Algarni, Marei Saeed Mohammed

    2016-09-15

    We present SurfCut, an algorithm for extracting a smooth simple surface with unknown boundary from a noisy 3D image and a seed point. In contrast to existing approaches that extract smooth simple surfaces with boundary, our method requires less user input, i.e., a seed point, rather than a 3D boundary curve. Our method is built on the novel observation that certain ridge curves of a front propagated using the Fast Marching algorithm are likely to lie on the surface. Using the framework of cubical complexes, we design a novel algorithm to robustly extract such ridge curves and form the surface of interest. Our algorithm automatically cuts these ridge curves to form the surface boundary, and then extracts the surface. Experiments show the robustness of our method to errors in the data, and that we achieve higher accuracy with lower computational cost than comparable methods. © Springer International Publishing AG 2016.

  19. Territorial disputes, identity conflicts, and violence in surfing

    Directory of Open Access Journals (Sweden)

    Marília Martins Bandeira

    2014-03-01

    Full Text Available Aggressive manifestations of localism are a current concern among surfers and are becoming well known as a result of specialized media. The objective of this paper was to investigate this phenomenon through the examination of a specific case and empirical fieldwork that was conducted for an ethnography of São Paulo surfers. The data were obtained via participant observations and open interviews. The results indicate that conflicts generally begin as disputes over the best waves. Surfing has a general rule of "wave priority criteria," based on spatial positioning. However, this universal rule may be intentionally broken depending on surfers' sociability. Ethnic and class differences based on historical processes can exist in oppositional relationships among surfers and are manifested by categories of accusation or identity (in São Paulo's case, local, haole, roots,prego,and playboy. However, this category attribution is contextual and interchangeable because surfers circulate between groups and beaches while searching for waves.

  20. ON PREDICTING INFRAGRAVITY ENERGY IN THE SURF ZONE.

    Science.gov (United States)

    Sallenger,, Asbury H.; Holman, Robert A.; Edge, Billy L.

    1985-01-01

    Flow data were obtained in the surf zone across a barred profile during a storm. RMS cross-shore velocities due to waves in the intragravity band (wave periods greater than 20 s) had maxima in excess of 0. 5 m/s over the bar crest. For comparison to measured spectra, synthetic spectra of cross-shore flow were computed using measured nearshore profiles. The structure, in the infragravity band, of these synthetic spectra corresponded reasonably well with the structure of the measured spectra. Total variances of measured cross-shore flow within the infragravity band were nondimensionalized by dividing by total infragravity variances of synthetic spectra. These nondimensional variances were independent of distance offshore and increased with the square of the breaker height. Thus, cross-shore flow due to infragravity waves can be estimated with knowledge of the nearshore profile and incident wave conditions. Refs.

  1. On analyzing colour constancy approach for improving SURF detector performance

    Science.gov (United States)

    Zulkiey, Mohd Asyraf; Zaki, Wan Mimi Diyana Wan; Hussain, Aini; Mustafa, Mohd. Marzuki

    2012-04-01

    Robust key point detector plays a crucial role in obtaining a good tracking feature. The main challenge in outdoor tracking is the illumination change due to various reasons such as weather fluctuation and occlusion. This paper approaches the illumination change problem by transforming the input image through colour constancy algorithm before applying the SURF detector. Masked grey world approach is chosen because of its ability to perform well under local as well as global illumination change. Every image is transformed to imitate the canonical illuminant and Gaussian distribution is used to model the global change. The simulation results show that the average number of detected key points have increased by 69.92%. Moreover, the average of improved performance cases far out weight the degradation case where the former is improved by 215.23%. The approach is suitable for tracking implementation where sudden illumination occurs frequently and robust key point detection is needed.

  2. SurfCut: Surfaces of Minimal Paths From Topological Structures

    KAUST Repository

    Algarni, Marei Saeed Mohammed; Sundaramoorthi, Ganesh

    2018-01-01

    We present SurfCut, an algorithm for extracting a smooth, simple surface with an unknown 3D curve boundary from a noisy image and a seed point. Our method is built on the novel observation that certain ridge curves of a function defined on a front propagated using the Fast Marching algorithm lie on the surface. Our method extracts and cuts these ridges to form the surface boundary. Our surface extraction algorithm is built on the novel observation that the surface lies in a valley of the distance from Fast Marching. We show that the resulting surface is a collection of minimal paths. Using the framework of cubical complexes and Morse theory, we design algorithms to extract these critical structures robustly. Experiments on three 3D datasets show the robustness of our method, and that it achieves higher accuracy with lower computational cost than state-of-the-art.

  3. Estuary-dependence of larval fishes in a non-estuary associated South African surf zone: evidence for continuity of surf assemblages

    Science.gov (United States)

    Strydom, Nadine A.; d'Hotman, Bruce D.

    2005-04-01

    Larval fishes were collected in the Cape Padrone surf zone on the southeast coast of South Africa, using a modified small-mesh seine net. The aim of the study was to assess the composition of fish larvae, with respect to their association with estuaries, in a surf zone that was not in close proximity to an estuary (>5 km). Sampling took place bimonthly during diurnal spring low tides between March and July 2003. In total, 544 fish were caught in the surf zone, comprising 14 families represented by 19 positively identified species, as well as an additional two species that were differentiated but remain unidentified. The families Mugilidae (65%) and Sparidae (26%) dominated the larval catch. The majority of larval fishes caught were in the postflexion stage of development, although some early juveniles were also caught. Body lengths of fish larvae ranged between 2 and 28 mm, with the majority of larvae at the recruitment size for the species. A high proportion of the fish species caught were estuary-dependent. Estuary-dependent marine fish larvae (categories I, II and IV) comprised 68% of total catch by species and 98% by number of individuals. Exclusively marine species (category III) were encountered in low numbers in the surf. The present study provides evidence for continuity in temperate South African surf zones in terms of domination by estuary-dependent larvae and reasons for this pattern are discussed.

  4. Military personnel recognition system using texture, colour, and SURF features

    Science.gov (United States)

    Irhebhude, Martins E.; Edirisinghe, Eran A.

    2014-06-01

    This paper presents an automatic, machine vision based, military personnel identification and classification system. Classification is done using a Support Vector Machine (SVM) on sets of Army, Air Force and Navy camouflage uniform personnel datasets. In the proposed system, the arm of service of personnel is recognised by the camouflage of a persons uniform, type of cap and the type of badge/logo. The detailed analysis done include; camouflage cap and plain cap differentiation using gray level co-occurrence matrix (GLCM) texture feature; classification on Army, Air Force and Navy camouflaged uniforms using GLCM texture and colour histogram bin features; plain cap badge classification into Army, Air Force and Navy using Speed Up Robust Feature (SURF). The proposed method recognised camouflage personnel arm of service on sets of data retrieved from google images and selected military websites. Correlation-based Feature Selection (CFS) was used to improve recognition and reduce dimensionality, thereby speeding the classification process. With this method success rates recorded during the analysis include 93.8% for camouflage appearance category, 100%, 90% and 100% rates of plain cap and camouflage cap categories for Army, Air Force and Navy categories, respectively. Accurate recognition was recorded using SURF for the plain cap badge category. Substantial analysis has been carried out and results prove that the proposed method can correctly classify military personnel into various arms of service. We show that the proposed method can be integrated into a face recognition system, which will recognise personnel in addition to determining the arm of service which the personnel belong. Such a system can be used to enhance the security of a military base or facility.

  5. Incidence of Ichthyophonus hoferi in Puget Sound fishes and its increase with age of Pacific herring

    Science.gov (United States)

    Hershberger, P.K.; Stick, K.; Bui, B.; Carroll, C.; Fall, B.; Mork, C.; Perry, J.A.; Sweeney, E.; Wittouck, J.; Winton, J.; Kocan, R.

    2002-01-01

    A recent decrease in the mean age of adult Pacific herring Clupea pallasi in Puget Sound was associated with a high prevalence of Ichthyophonus hoferi, a protistan parasite that can be highly pathogenic to Pacific herring. In Puget Sound, high intensities of I. hoferiinfection may be maintained in older cohorts of Pacific herring because the prevalence ofI. hoferi increased with age from 12% among juveniles to 58% among the oldest, age-6 and older cohorts. Low intensities of I. hoferi infection in the region may be maintained in alternative fish hosts, such as surf smelt Hypomesus pretiosus, Puget Sound rockfishSebastes emphaeus, Pacific tomcod Microgadus proximus, and speckled sanddabCithanichthys stigmaeus.

  6. Wave Breaking, Bubble Production and Acoustic Characteristics of the Surf Zone, SIO Component

    National Research Council Canada - National Science Library

    Deane, Grant

    2001-01-01

    .... The purpose of these measurements was to: (1) statistically characterize the surf zone acoustic channel Doppler and time spreads, and acoustic drop-outs, in terms of the incident wave field and (2...

  7. Sustainable Urban Fringes - Connecting Urban and Rural : Final report of the SURF project

    NARCIS (Netherlands)

    Bruijn, de T.J.N.M. (Theo); Haccoû, H.A. (Huib); Leslie, A. (Allison); Lier, G. (Goos); Littlewood, S. (Stephan); Oldejans, R. (Rolf); Thomas, K. (Kevin); Vries, de B.J. (Bauke); Watt, E. (Emma); Wishardt, M. (Michelle)

    2012-01-01

    What happens at the urban edge and the SURF aspiration to influence it? Projects in the urban fringe Urban fringe governance Integrated policy guidelines and approaches towards urban fringe planning and management The future management of the urban fringe

  8. The rate of beneficial mutations surfing on the wave of a range expansion.

    Directory of Open Access Journals (Sweden)

    Rémi Lehe

    Full Text Available Many theoretical and experimental studies suggest that range expansions can have severe consequences for the gene pool of the expanding population. Due to strongly enhanced genetic drift at the advancing frontier, neutral and weakly deleterious mutations can reach large frequencies in the newly colonized regions, as if they were surfing the front of the range expansion. These findings raise the question of how frequently beneficial mutations successfully surf at shifting range margins, thereby promoting adaptation towards a range-expansion phenotype. Here, we use individual-based simulations to study the surfing statistics of recurrent beneficial mutations on wave-like range expansions in linear habitats. We show that the rate of surfing depends on two strongly antagonistic factors, the probability of surfing given the spatial location of a novel mutation and the rate of occurrence of mutations at that location. The surfing probability strongly increases towards the tip of the wave. Novel mutations are unlikely to surf unless they enjoy a spatial head start compared to the bulk of the population. The needed head start is shown to be proportional to the inverse fitness of the mutant type, and only weakly dependent on the carrying capacity. The precise location dependence of surfing probabilities is derived from the non-extinction probability of a branching process within a moving field of growth rates. The second factor is the mutation occurrence which strongly decreases towards the tip of the wave. Thus, most successful mutations arise at an intermediate position in the front of the wave. We present an analytic theory for the tradeoff between these factors that allows to predict how frequently substitutions by beneficial mutations occur at invasion fronts. We find that small amounts of genetic drift increase the fixation rate of beneficial mutations at the advancing front, and thus could be important for adaptation during species invasions.

  9. The Effect of a Single Bout of Surfing on Exercise-Induced Affect

    OpenAIRE

    PITTSINGER, RYAN; KRESS, JEFF; CRUSSEMEYER, JILL

    2017-01-01

    Exercise-induced affect (EIA) has been well documented and is often composed of positive affect, negative affect, tranquility, and fatigue. Research on EIA has focused on mainstream sports such as running, walking, or cycling; however, no research has evaluated the influence of action sports participation in activities such surfing on EIA. The current study examined the effect of a single 30-min surfing bout on EIA in 107 adult volunteers. An additional purpose was if change in affect was sim...

  10. The study of online hospitality exchange : The case of couch surfing network

    OpenAIRE

    Zaki, Taher

    2015-01-01

    The work presented here firstly aims at creating awareness about the whole concept of ‘couch surfing,’ relatively a new phenomenon when seeking ‘alternative’ and inexpensive ways to travel to new destinations. This particular research work outlines the emphasis and prospects of alternative ways to travel nowadays. It then progresses to explaining about the couch surfing idea, how it functions as well as its benefits and criticisms. The theoretical framework of this research is based on the mo...

  11. Surfing depth on a behaviour change website: predictors and effects on behaviour.

    Science.gov (United States)

    Jacobs, Nele; De Bourdeaudhuij, Ilse; Claes, Neree

    2010-03-01

    The primary objectives of the present study were to gain insight into website use and to predict the surfing depth on a behaviour change website and its effect on behaviour. Two hundred eight highly educated adults from the intervention condition of a randomised trial received access to a medical intervention, individual coaching (by e-mail, post, telephone or face-to-face) and a behaviour change website. Website use (e.g. surfing depth, page view duration) was registered. Online questionnaires for physical activity and fat intake were filled out at baseline and after 6 months. Hierarchical linear regression was used to predict surfing depth and its effect on behaviour. Seventy-five per cent of the participants visited the website. Fifty-one and fifty-six per cent consulted the physical activity and fat intake feedback, respectively. The median surfing depth was 2. The total duration of interventions by e-mail predicted deeper surfing (beta=0.36; pSurfing depth did not predict changes in fat intake (beta=-0.07; p=0.45) or physical activity (beta=-0.03; p=0.72). Consulting the physical activity feedback led to more physical activity (beta=0.23; p=0.01). The findings from the present study can be used to guide future website development and improve the information architecture of behaviour change websites.

  12. Simple estimate of entrainment rate of pollutants from a coastal discharge into the surf zone.

    Science.gov (United States)

    Wong, Simon H C; Monismith, Stephen G; Boehm, Alexandria B

    2013-10-15

    Microbial pollutants from coastal discharges can increase illness risks for swimmers and cause beach advisories. There is presently no predictive model for estimating the entrainment of pollution from coastal discharges into the surf zone. We present a novel, quantitative framework for estimating surf zone entrainment of pollution at a wave-dominant open beach. Using physical arguments, we identify a dimensionless parameter equal to the quotient of the surf zone width l(sz) and the cross-flow length scale of the discharge la = M(j) (1/2)/U(sz), where M(j) is the discharge's momentum flux and U(sz) is a representative alongshore velocity in the surf zone. We conducted numerical modeling of a nonbuoyant discharge at an alongshore uniform beach with constant slope using a wave-resolving hydrodynamic model. Using results from 144 numerical experiments we develop an empirical relationship between the surf zone entrainment rate α and l(sz)/(la). The empirical relationship can reasonably explain seven measurements of surf zone entrainment at three diverse coastal discharges. This predictive relationship can be a useful tool in coastal water quality management and can be used to develop predictive beach water quality models.

  13. The greenscape shapes surfing of resource waves in a large migratory herbivore.

    Science.gov (United States)

    Aikens, Ellen O; Kauffman, Matthew J; Merkle, Jerod A; Dwinnell, Samantha P H; Fralick, Gary L; Monteith, Kevin L

    2017-06-01

    The Green Wave Hypothesis posits that herbivore migration manifests in response to waves of spring green-up (i.e. green-wave surfing). Nonetheless, empirical support for the Green Wave Hypothesis is mixed, and a framework for understanding variation in surfing is lacking. In a population of migratory mule deer (Odocoileus hemionus), 31% surfed plant phenology in spring as well as a theoretically perfect surfer, and 98% surfed better than random. Green-wave surfing varied among individuals and was unrelated to age or energetic state. Instead, the greenscape, which we define as the order, rate and duration of green-up along migratory routes, was the primary factor influencing surfing. Our results indicate that migratory routes are more than a link between seasonal ranges, and they provide an important, but often overlooked, foraging habitat. In addition, the spatiotemporal configuration of forage resources that propagate along migratory routes shape animal movement and presumably, energy gains during migration. © 2017 John Wiley & Sons Ltd/CNRS.

  14. Qualitative Task Analysis to Enhance Sports Characterization: A Surfing Case Study

    Directory of Open Access Journals (Sweden)

    Moreira Miguel

    2014-10-01

    Full Text Available The aim of this study was to develop a Matrix of Analysis for Sports Tasks (MAST, regardless of the sports activity, based on practice classification and task analysis. Being this a qualitative research our main question was: in assessing sports’ structure is it possible to make the characterization of any discipline through context and individuals’ behaviours? The sample was within a surf discipline in a competition flowing having 5 of the top 16 Portuguese surfers training together. Based on a qualitative method, studying the surf as the main activity was an interpretative study case. The MAST was applied in four phases: taxonomy; tasks and context description; task analysis; teaching and performance strategies. Its application allowed the activities’ characterization through the observation, surfer’s opinions and bibliographical support. The triangulation of the data was used as an information data treatment. The elements were classified by the challenges proposed to the practitioners and the taxonomy was constituted by the sport activities, group, modality and discipline. Surf is a discipline of surfing which is a sliding sport modality, therefore, a nature sport. In the context description, we had the wave’s components and constraints and the surfboards’ qualities. Through task analysis we obtained a taxonomy of surf manoeuvres. The structural and functional analysis allowed finding solutions for learning of surf techniques with trampoline and skateboards because these fit in sliding sports. MAST makes possible the development of strategies that benefit teaching and performance intervention

  15. Qualitative Task Analysis to Enhance Sports Characterization: A Surfing Case Study

    Science.gov (United States)

    Moreira, Miguel; Peixoto, César

    2014-01-01

    The aim of this study was to develop a Matrix of Analysis for Sports Tasks (MAST), regardless of the sports activity, based on practice classification and task analysis. Being this a qualitative research our main question was: in assessing sports’ structure is it possible to make the characterization of any discipline through context and individuals’ behaviours? The sample was within a surf discipline in a competition flowing having 5 of the top 16 Portuguese surfers training together. Based on a qualitative method, studying the surf as the main activity was an interpretative study case. The MAST was applied in four phases: taxonomy; tasks and context description; task analysis; teaching and performance strategies. Its application allowed the activities’ characterization through the observation, surfer’s opinions and bibliographical support. The triangulation of the data was used as an information data treatment. The elements were classified by the challenges proposed to the practitioners and the taxonomy was constituted by the sport activities, group, modality and discipline. Surf is a discipline of surfing which is a sliding sport modality, therefore, a nature sport. In the context description, we had the wave’s components and constraints and the surfboards’ qualities. Through task analysis we obtained a taxonomy of surf manoeuvres. The structural and functional analysis allowed finding solutions for learning of surf techniques with trampoline and skateboards because these fit in sliding sports. MAST makes possible the development of strategies that benefit teaching and performance intervention. PMID:25414757

  16. Characterization of Activity and Cardiovascular Responses During Surfing in Recreational Male Surfers Between the Ages of 18 and 75 Years Old.

    Science.gov (United States)

    LaLanne, Christine L; Cannady, Michael S; Moon, Joseph F; Taylor, Danica L; Nessler, Jeff A; Crocker, George H; Newcomer, Sean C

    2017-04-01

    Participation in surfing has evolved to include all age groups. Therefore, the purpose of this study was to determine whether activity levels and cardiovascular responses to surfing change with age. Surfing time and heart rate (HR) were measured for the total surfing session and within each activity of surfing (paddling, sitting, wave riding, and miscellaneous). Peak oxygen consumption (VO 2peak ) was also measured during laboratory-based simulated surfboard paddling on a modified swim bench ergometer. VO 2peak decreased with age during simulated paddling (r = -.455, p surfing (p = .837) and time spent within each activity of surfing did not differ with age (n = 160). Mean HR during surfing significantly decreased with age (r = -.231, p = .004). However, surfing HR expressed as a percent of age-predicted maximum increased significantly with age. Therefore, recreational surfers across the age spectrum are achieving intensities and durations that are consistent with guidelines for cardiovascular health.

  17. Age, growth and sex composition of the American smelt Osmerus mordax(Mitchill), of western Lake Superior

    Science.gov (United States)

    Bailey, Merryll M.

    1964-01-01

    This study is based on 4,561 smelt collected in Chequamegon Bay, the Apostle Islands, the Brule River, and Superior Harbor, all in western Lake Superior. Commercial production in the Great Lakes (U.S. and Canada combined) reached a peak of nearly 16 million pounds in 1960. Production in Lake Superior has generally been small but increased during the 1950's to reach 948,000 pounds in 1960. All O-group and spring I-group smelt had scales with sufficient sculpturing to permit detection of the first annulus. Annulus formation began after 6 June in 1960. In 1961, all smelt had completed the annulus by 24 August. The body-scale relation is a straight line with an intercept of -0.9 inch on the axis of fish length. The weight of western Lake Superior smelt increased as the 2.952 power of the length. A large range of length in each age group and resulting overlap of age-groups II-VI made length a poor index of age. Female smelt grew faster than males after the second year and dominated strongly in age-groups IV-VII. Both sexes made their best annual growth in length (3.3 inches) during their second year of life; the largest weight increments (0.74 ounce, males; 0.85 ounce, females) came in the third year. Best production from a commercial pound net in 1961 occurred when the sex ratios of spawning smelt were nearest 50:50. Spawning male smelt were consistently shorter than females and the average lengths of both sexes decreased as the spawning season progressed. Shortest mature smelt of each sex were 5.0 to 5.2 inches but the males are probably the first to reach 100 percent maturity. All year-old smelt were immature. Among 2-year-old fish, 40.7 per cent of the males and 17.7 percent of the females had reached maturity. All smelt more than 2 years old were mature. Ovaries of 10 smelt contained an average of 31,338 eggs for fish 7.3 to 8.8 inches long.

  18. “100 percent fun”: A case study of benefits from cold water surfing in Jæren, Norway

    OpenAIRE

    Elmahdy, Yasmine Mounir

    2015-01-01

    Master's thesis in International hotel and tourism management Norway is steadily progressing towards being a popular cold-water surf destination. The long Norwegian coastline is attracting an increasing number of surfers who surf year round in extreme weather conditions. The aim of this research is to identify the benefits acquired by Norwegian surfers surfing in cold water along the Jæren coast, south the city of Stavanger in Norway. This research adopted a phenomenological approach and q...

  19. Larval nematodes in stomach wall granulomas of smelt Osmerus eperlanus from the German North Sea coast

    OpenAIRE

    Obiekezie, A. I.; Lick, Roland R.; Kerstan, Susanne L.; Möller, Heino

    1992-01-01

    Occurrence of stomach wall granulomas in European smelt was studled at 6 locations along the German North Sea coast. Identification of larval nematodes inhabiting these granulomas is provided for the first time. Three species, isolated by pepsin-HC1 digestion, are involved: Hysterothylacium cf. cornutum, Cosmocephalus obvelatus and Paracuaria tridentata. 72% of all stomachs examined were affected. The ratio of number of granulomas to number of the 3 larval species free in the mesentery was 1:...

  20. The Effect Of Local Coal And Smelting Sponge Iron On Iron Content Of Pig Iron

    Science.gov (United States)

    Oediyani, Soesaptri; Juwita Sari, Pramita; Hadi P, Djoko

    2018-03-01

    The new regulation on mineral resources was announced by Ministry of Energy and Mineral resources (ESDM) of Indonesia at 2014 which it called Permen ESDM No 1/2014. Therefore, this research was conducted to add the value of local iron ores by using smelting technology. The objective of the research is to produce pig iron that meet the requirement of the new regulation of mineral resources such as 90% Fe. First, iron ores and coal mixed together with lime as a flux, then smelted in a Electric Arc Furnace at 1800°C. The process variables are (1; 1.25; 1.5; 1.75; 2.0) and the composition of coal (0.8%, 1.6%, 3.0%). The type of coal that used in this research was bituminous coal from Kalimantan and also the iron ores from Kalimantan. The products of the smelting technology are Pig iron and slag. Both pig iron and slag then analyzed by SEM-EDS to measure the iron content. The result shows that the maximum iron content on pig iron is about 95.04% meanwhile the minimum iron content on slag is about 3.66%. This result achieved at 1.6% coal and 2.0.

  1. Aspects of energy reduction by autogenous copper production in the copper smelting plant Bor

    International Nuclear Information System (INIS)

    Najdenov, Ivan; Raić, Karlo T.; Kokeza, Gordana

    2012-01-01

    This work presents a comparative analysis of the energy consumption during copper production by the “standard” procedure (roasting in a fluo–solid reactor and smelting in a reverberatory furnace) in the Smelting Plant in Bor with modern autogenous procedures. All forms of expended energy were reduced to primary energy or to the same energy form, i.e., to the energy equivalent of the process (EEP), the raw material and the process materials. In addition, the energy equivalent of the process and waste products (water vapour, thermal energy and similar) were balanced. To complete the consumption of all energy generating products in copper production, they were reduced to conditional fuel (coal equivalent = 29.3 MJ/kg). Additionally, this study suggests replacement of the existing technology by an appropriate autogenous procedure and considers the prospects for further development of mining and metallurgy in Bor. Estimates of development perspectives for copper production should be comprehensive, based on complete and relevant data, as well as on real considerations of future development in world production. -- Highlights: ► “Standard” autogenous copper production in the Smelting Plant, Bor, Serbia. ► Comparation of energy consumption in “standard” with other autogenous procedures. ► All forms of energy are reduced to energy equivalent and conditional fuel. ► Replacement of existing technology with the appropriate autogenous procedure. ► Perspectives of further development of mining and metallurgy in Bor.

  2. Inverse boundary design of a radiative smelting furnace with ablative phase change phenomena

    International Nuclear Information System (INIS)

    Farzan, H.; Hosseini Sarvari, S.M.; Mansouri, S.H.

    2016-01-01

    Highlights: • The ablation phenomenon in a reverberatory smelting furnace is simulated numerically. • The results are verified by comparing with exact analytic solution. • Inverse design problem is solved to construct the desired melting rate. • The conjugate gradient method is used to solve the inverse phase change problem. - Abstract: An inverse analysis is employed to control the time rate of heaters in a 2-D smelting furnace to provide the specified radiative heat flux across the design surface to establish a desired melting rate. The design surface in the smelting furnace is the melting surface of the metal concentrate bank, and the melting process is considered to occur as an ablation phenomenon. The net radiation method is used to determine the radiation exchange between the elements of the furnace surfaces and the melting surface. The conjugate gradient method is employed to minimize the objective function, which is the sum of square residuals between the estimated and the desired heat fluxes over the design surface. It is shown that the proposed inverse technique is reliable and accurate for predicting the heater power distribution.

  3. Surf zone entrainment, along-shore transport, and human health implications of pollution from tidal outlets

    Science.gov (United States)

    Grant, S. B.; Kim, J. H.; Jones, B. H.; Jenkins, S. A.; Wasyl, J.; Cudaback, C.

    2005-10-01

    Field experiments and modeling studies were carried out to characterize the surf zone entrainment and along-shore transport of pollution from two tidal outlets that drain into Huntington Beach and Newport Beach, popular public beaches in southern California. The surf zone entrainment and near-shore transport of pollutants from these tidal outlets appears to be controlled by prevailing wave conditions and coastal currents, and fine-scale features of the flow field around the outlets. An analysis of data from dye experiments and fecal indicator bacteria monitoring studies reveals that the along-shore flux of surf zone water is at least 50 to 300 times larger than the cross-shore flux of surf zone water. As a result, pollutants entrained in the surf zone hug the shore, where they travel significant distances parallel to the beach before diluting to extinction. Under the assumption that all surf zone pollution at Huntington Beach originates from two tidal outlets, the Santa Ana River and Talbert Marsh outlets, models of mass and momentum transport in the surf zone approximately capture the observed tidal phasing and magnitude of certain fecal indicator bacteria groups (total coliform) but not others (Escherichia coli and enterococci), implying the existence of multiple sources of, and/or multiple transport pathways for, fecal pollution at this site. The intersection of human recreation and near-shore pollution pathways implies that, from a human health perspective, special care should be taken to reduce the discharge of harmful pollutants from land-side sources of surface water runoff, such as tidal outlets and storm drains.

  4. Green‐wave surfing increases fat gain in a migratory ungulate

    Science.gov (United States)

    Middleton, Arthur D.; Merkle, Jerod A.; McWhirter, Douglas E.; Cook, John G.; Cook, Rachel C.; White, P.J.; Kauffman, Matthew J.

    2018-01-01

    Each spring, migratory herbivores around the world track or ‘surf’ green waves of newly emergent vegetation to distant summer or wet‐season ranges. This foraging tactic may help explain the great abundance of migratory herbivores on many seasonal landscapes. However, the underlying fitness benefits of this life‐history strategy remain poorly understood. A fundamental prediction of the green‐wave hypothesis is that migratory herbivores obtain fitness benefits from surfing waves of newly emergent vegetation more closely than their resident counterparts. Here we evaluate whether this behavior increases body‐fat levels – a critically important correlate of reproduction and survival for most ungulates – in elk Cervus elaphus of the Greater Yellowstone Ecosystem. Using satellite imagery and GPS tracking data, we found evidence that migrants (n = 23) indeed surfed the green wave, occupying sites 12.7 days closer to peak green‐up than residents (n = 16). Importantly, individual variation in surfing may help account for up to 6 kg of variation in autumn body‐fat levels. Our findings point to a pathway for anthropogenic changes to the green wave (e.g. climate change) or migrants’ ability to surf it (e.g. development) to impact migratory populations. To explore this possibility, we evaluated potential population‐level consequences of constrained surfing with a heuristic model. If green‐wave surfing deteriorates by 5–15 days from observed, our model predicts up to a 20% decrease in pregnancy rates, a 2.5% decrease in population growth, and a 30% decrease in abundance over 50 years. By linking green‐wave surfing to fitness and illustrating potential effects on population growth, our study provides new insights into the evolution of migratory behavior and the prospects for the persistence of migratory ungulate populations in a changing world.

  5. Vortex-induced suspension of sediment in the surf zone

    Science.gov (United States)

    Otsuka, Junichi; Saruwatari, Ayumi; Watanabe, Yasunori

    2017-12-01

    A major mechanism of sediment suspension by organized vortices produced under violent breaking waves in the surf zone was identified through physical and computational experiments. Counter-rotating flows within obliquely descending eddies produced between adjacent primary roller vortices induce transverse convergent near-bed flows, driving bed load transport to form regular patterns of transverse depositions. The deposited sediment is then rapidly ejected by upward carrier flows induced between the vortices. This mechanism of vortex-induced suspension is supported by experimental evidence that coherent sediment clouds are ejected where the obliquely descending eddies reach the sea bed after the breaking wave front has passed. In addition to the effects of settling and turbulent diffusion caused by breaking waves, the effect of the vortex-induced flows was incorporated into a suspension model on the basis of vorticity dynamics and parametric characteristics of transverse flows in breaking waves. The model proposed here reasonably predicts an exponential attenuation of the measured sediment concentration due to violent plunging waves and significantly improves the underprediction of the concentration produced by previous models.

  6. Surfing through hyperspace understanding higher universes in six easy lessons

    CERN Document Server

    Pickover, Clifford A

    1999-01-01

    Do a little armchair time-travel, rub elbows with a four-dimensional intelligent life form, or stretch your mind to the furthest corner of an uncharted universe. With this astonishing guidebook, Surfing Through Hyperspace, you need not be a mathematician or an astrophysicist to explore the all-but-unfathomable concepts of hyperspace and higher-dimensional geometry. No subject in mathematics has intrigued both children and adults as much as the idea of a fourth dimension. Philosophers and parapsychologists have meditated on this mysterious space that no one can point to but may be all around us. Yet this extra dimension has a very real, practical value to mathematicians and physicists who use it every day in their calculations. In the tradtion of Flatland, and with an infectious enthusiasm, Clifford Pickover tackles the problems inherent in our 3-D brains trying to visualize a 4-D world, muses on the religious implications of the existence of higher-dimensional consciousness, and urges all curious readers to v...

  7. Spinal cord injury with central cord syndrome from surfing.

    Science.gov (United States)

    Steinfeld, Yaniv; Keren, Yaniv; Haddad, Elias

    2018-01-01

    Central cord syndrome (CCS) is an injury to the center of the spinal cord. It is well known as a hyperextension injury, but it has never been described as a surfing injury. Our report describes this injury in detail. A 35-year-old male novice surfer presented to the emergency department with acute tetraplegia following falling off his surfboard and hitting sea floor at a shallow beach break. He was rescued by a fellow surfer while floating in the sea and unable to raise his head above sea level. Upon arrival at the hospital, tetraplegia and sensory deficits were noted. Radiological investigations showed advanced spinal stenosis at C4-6 levels. T2 magnetic resonance imaging (MRI) demonstrated myelopathy at C5-C6 level. He was diagnosed as having central cord syndrome, treated conservatively, and regained near full neurologic recovery after a month of rehabilitation. Unique sport activities lead to unique injuries. It is important to accurately describe these injuries in order to create protective measures against them. Neurologic injuries in surfers are uncommon. With low-energy trauma, surfer's myelopathy is still the most common diagnosis, but central cord syndrome should be in the differential diagnosis.

  8. Surfing with capillary waves: a survival strategy for trapped bees

    Science.gov (United States)

    Roh, Chris; Gharib, Morteza

    2017-11-01

    Honeybees are able to propel themselves at the water surface. A rapid vibration (30-220 Hz) of wings at the air-water interface results in a locomotion speed of 3-4 cm/s. A mechanism for generating thrust required for achieving and maintaining such speed must be different from their mechanism of flight inasmuch as they are in a different fluid environment. In this study, we present the thrust generating mechanism of the honeybee at the air-water interface. A close observation of the wing's interaction with the water surface showed that the wing does not penetrate nor detach from the water surface. Moreover, the stroke speed of the wing exceeds the minimum capillary wave speed, which signifies that the wing constantly generates the capillary wave by pulling on the surface with its wetted underside. Observation of such interaction suggests that honeybee's locomotion at the water surface resembles surfing on the self-generated capillary wave. A further evidence of described mechanism is explored by constructing a similarly sized mechanical model. This material is based upon work supported by the National Science Foundation under Grant No. CBET-1511414; additional support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469.

  9. Thallium transformation and partitioning during Pb–Zn smelting and environmental implications

    International Nuclear Information System (INIS)

    Liu, Juan; Wang, Jin; Chen, Yongheng; Xie, Xiaofan; Qi, Jianying; Lippold, Holger; Luo, Dinggui; Wang, Chunlin; Su, Longxiao; He, Lucheng; Wu, Qiwei

    2016-01-01

    Thallium (Tl) is a toxic and non-essential heavy metal. Raw Pb–Zn ores and solid smelting wastes from a large Pb–Zn smelting plant – a typical thallium (Tl) pollution source in South China, were investigated in terms of Tl distribution and fractionation. A modified IRMM (Institute for Reference Materials and Measurement, Europe) sequential extraction scheme was applied on the samples, in order to uncover the geochemical behavior and transformation of Tl during Pb–Zn smelting and to assess the potential environmental risk of Tl arising from this plant. Results showed that the Pb–Zn ore materials were relatively enriched with Tl (15.1–87.7 mg kg"−"1), while even higher accumulation existed in the electrostatic dust (3280–4050 mg kg"−"1) and acidic waste (13,300 mg kg"−"1). A comparison of Tl concentration and fraction distribution in different samples clearly demonstrated the significant role of the ore roasting in Tl transformation and mobilization, probably as a result of alteration/decomposition of related minerals followed by Tl release and subsequent deposition/co-precipitation on fine surface particles of the electrostatic dust and acidic waste. While only 10–30% of total Tl amounts was associated with the exchangeable/acid-extractable fraction of the Pb–Zn ore materials, up to 90% of total Tl was found in this fraction of the electrostatic dust and acidic waste. Taking into account the mobility and bioavailability of this fraction, these waste forms may pose significant environmental risk. - Highlights: • Geo-chemical partitioning of Tl in Pb–Zn ores and smelting wastes was investigated. • Significant differences were shown in Tl contents and chemical fractionation. • Over 100-fold enrichment of Tl was found in electrostatic dust and acidic waste. • Ore roasting played a key role in Tl transformation and mobilization. • Tl was mainly bound in the labile fraction of electrostatic dust and acidic waste. - Geo

  10. Improved SURF Algorithm and Its Application in Seabed Relief Image Matching

    Directory of Open Access Journals (Sweden)

    Zhang Hong-Mei

    2017-01-01

    Full Text Available The matching based on seabed relief image is widely used in underwater relief matching navigation and target recognition, etc. However, being influenced by various factors, some conventional matching algorithms are difficult to obtain an ideal result in the matching of seabed relief image. SURF(Speeded Up Robust Features algorithm is based on feature points pair to achieve matching, and can get good results in the seabed relief image matching. However, in practical applications, the traditional SURF algorithm is easy to get false matching, especially when the area’s features are similar or not obvious, the problem is more seriously. In order to improve the robustness of the algorithm, this paper proposes an improved matching algorithm, which combines the SURF, and RANSAC (Random Sample Consensus algorithms. The new algorithm integrates the two algorithms advantages, firstly, the SURF algorithm is applied to detect and extract the feature points then to pre-match. Secondly, RANSAC algorithm is utilized to eliminate mismatching points, and then the accurate matching is accomplished with the correct matching points. The experimental results show that the improved algorithm overcomes the mismatching problem effectively and have better precision and faster speed than the traditional SURF algorithm.

  11. Factors affecting surf zone phytoplankton production in Southeastern North Carolina, USA

    KAUST Repository

    Cahoon, Lawrence B.

    2017-07-15

    Abstract: The biomass and productivity of primary producers in the surf zone of the ocean beach at Wrightsville Beach, North Carolina, USA, were measured during all seasons, along with environmental parameters and nutrient levels. Variation in biomass (chlorophyll a) was associated with temperature. Primary production (PP), measured by in situ 14-C incubations, was a function of chlorophyll a, tide height at the start of incubations, and rainfall in the preceding 24-hr period. Biomass-normalized production (PB) was also a function of tide height and rainfall in the preceding 24-hr period. We interpreted these results as evidence of surf production 1) as combined contributions of phytoplankton and suspended benthic microalgae, which may confound application of simple P-E models to surf zone production, and 2) being regulated by nutrient source/supply fluctuations independently from other factors. Surf zone biomass and production levels are intermediate between relatively high estuarine values and much lower coastal ocean values. Surf zone production may represent an important trophic connection between these two important ecosystems.

  12. Factors affecting surf zone phytoplankton production in Southeastern North Carolina, USA

    KAUST Repository

    Cahoon, Lawrence B.; Bugica, Kalman; Wooster, Michael K.; Dickens, Amanda Kahn

    2017-01-01

    Abstract: The biomass and productivity of primary producers in the surf zone of the ocean beach at Wrightsville Beach, North Carolina, USA, were measured during all seasons, along with environmental parameters and nutrient levels. Variation in biomass (chlorophyll a) was associated with temperature. Primary production (PP), measured by in situ 14-C incubations, was a function of chlorophyll a, tide height at the start of incubations, and rainfall in the preceding 24-hr period. Biomass-normalized production (PB) was also a function of tide height and rainfall in the preceding 24-hr period. We interpreted these results as evidence of surf production 1) as combined contributions of phytoplankton and suspended benthic microalgae, which may confound application of simple P-E models to surf zone production, and 2) being regulated by nutrient source/supply fluctuations independently from other factors. Surf zone biomass and production levels are intermediate between relatively high estuarine values and much lower coastal ocean values. Surf zone production may represent an important trophic connection between these two important ecosystems.

  13. KARAKTERISTIK, MOTIVASI DAN NIAT WISATAWAN SURFING DI PANTAI KECAMATAN KUTA UTARA

    Directory of Open Access Journals (Sweden)

    Ni Putu Windy Pramita

    2017-04-01

    Full Text Available Black sandy beach tourist attraction of Kuta Northen region that is Batu Bolong beach and Batu Mejan beach which has potential a beautifull oncean, sunset, sunbathing and surfingthe purpose of this study was to determinethe characteristics, motivasi, and intentions rating surfing at Kuta Northen beach. The method used observation, questionnaires, interviews, literature study, and documentation. 213 respondens rating surfing with quantitative descriptive and regression linier analisys. The result obtained in this study are based on age characteristics surfing travelers will see the most travelers age between 18-29 years, male gender, country of origin Australia, and is a businessman, a master degree educational level, and marital status is not married. Surfing tourist motivation using push and pull factor with the highest scores on the social interaction. And Intention surfing tourist with the highest score there is positive world of mouth with Variabel tourist have the effect of 13,20% with a probability level of sig. 0,000, the motivation positive and significant efeect on the intention tourist but in small quantities. Therefore to improve the intention tourist come to the beach district of north kuta from the motivation pull and push should also improve the quality of beaches such as keeping the beach becomes the most importans thing that will directly make tourist feel comfortable. advice for managers is to add a lifeguard to keep the beach.

  14. Factors affecting surf zone phytoplankton production in Southeastern North Carolina, USA

    Science.gov (United States)

    Cahoon, Lawrence B.; Bugica, Kalman; Wooster, Michael K.; Dickens, Amanda Kahn

    2017-09-01

    The biomass and productivity of primary producers in the surf zone of the ocean beach at Wrightsville Beach, North Carolina, USA, were measured during all seasons, along with environmental parameters and nutrient levels. Variation in biomass (chlorophyll a) was associated with temperature. Primary production (PP), measured by in situ 14-C incubations, was a function of chlorophyll a, tide height at the start of incubations, and rainfall in the preceding 24-hr period. Biomass-normalized production (PB) was also a function of tide height and rainfall in the preceding 24-hr period. We interpreted these results as evidence of surf production 1) as combined contributions of phytoplankton and suspended benthic microalgae, which may confound application of simple P-E models to surf zone production, and 2) being regulated by nutrient source/supply fluctuations independently from other factors. Surf zone biomass and production levels are intermediate between relatively high estuarine values and much lower coastal ocean values. Surf zone production may represent an important trophic connection between these two important ecosystems.

  15. Computing OpenSURF on OpenCL and General Purpose GPU

    Directory of Open Access Journals (Sweden)

    Wanglong Yan

    2013-10-01

    Full Text Available Speeded-Up Robust Feature (SURF algorithm is widely used for image feature detecting and matching in computer vision area. Open Computing Language (OpenCL is a framework for writing programs that execute across heterogeneous platforms consisting of CPUs, GPUs, and other processors. This paper introduces how to implement an open-sourced SURF program, namely OpenSURF, on general purpose GPU by OpenCL, and discusses the optimizations in terms of the thread architectures and memory models in detail. Our final OpenCL implementation of OpenSURF is on average 37% and 64% faster than the OpenCV SURF v2.4.5 CUDA implementation on NVidia's GTX660 and GTX460SE GPUs, repectively. Our OpenCL program achieved real-time performance (>25 Frames Per Second for almost all the input images with different sizes from 320*240 to 1024*768 on NVidia's GTX660 GPU, NVidia's GTX460SE GPU and AMD's Radeon HD 6850 GPU. Our OpenCL approach on NVidia's GTX660 GPU is more than 22.8 times faster than its original CPU version on Intel's Dual-Core E5400 2.7G on average.

  16. Contamination and human health risk of lead in soils around lead/zinc smelting areas in China.

    Science.gov (United States)

    Lei, Kai; Giubilato, Elisa; Critto, Andrea; Pan, Huiyun; Lin, Chunye

    2016-07-01

    Pb/Zn smelting, an important economic activity in China, has led to heavy environmental pollution. This research reviewed studies on soil Pb contamination at Pb/Zn smelting sites in China published during the period of 2000 to 2015 to clarify the total levels, spatial changes, and health risks for Pb contamination in soils at local and national scales. The results show that Pb contents in surface soils at 58 Pb/Zn smelting sites in China ranged from 7 to 312,452 mg kg(-1) with an arithmetic average, geometric average, and median of 1982, 404, and 428 mg kg(-1), respectively (n = 1011). Surface soil Pb content at these smelting sites decreased from an average of 2466 to 659 mg kg(-1), then to 463 mg kg(-1) as the distance from the smelters increased from 2000 m. With respect to variation with depth, the average soil Pb content at these sites gradually decreased from 986 mg kg(-1) at 0- to 20-cm depth to 144 mg kg(-1) at 80- to 100-cm depth. Approximately 78 % of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites were classified as having high Pb pollution levels. Approximately 34.2 and 7.7 % of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites might pose adverse health effects and high chronic risks to children, respectively. The Pb/Zn smelting sites in the southwest and southeast provinces of China, as well as Liaoning province, were most contaminated and thus should receive priority for remediation.

  17. Scaled photographs of surf over the full range of breaker sizes on the north shore of Oahu and Jaws, Maui, Hawaiian Islands (NODC Accession 0001753)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital surf photographs were scaled using surfers as height benchmarks to estimate the size of the breakers. Historical databases for surf height in Hawaii are...

  18. 76 FR 55566 - Safety Zones; Fireworks Displays and Surfing Events in Captain of the Port Long Island Sound Zone

    Science.gov (United States)

    2011-09-08

    ...-AA00 Safety Zones; Fireworks Displays and Surfing Events in Captain of the Port Long Island Sound Zone... zones for marine events within the Captain of the Port (COTP) Long Island Sound Zone for a surfing event... unless authorized by the COTP Sector Long Island Sound. DATES: This rule is effective in the CFR on...

  19. The State of stress in the Sanford Underground Research Facility (SURF) in Lead South Dakota

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Moo Y. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    As a part of the U.S. Department of Energy (DOE) SubTER (Subsurface Technology and Engineering Research, Development and Demonstration) initiative, University of Wisconsin- Madison, Sandia National Laboratories, and Lawrence Berkeley National Laboratory conducted the Permeability (k) and Induced Seismicity Management for Energy Technologies (kISMET) project. The objectives of the project are to define the in situ status of stress in the Sanford Underground Research Facility (SURF) in Lead, South Dakota and to establish the relations between in situ stress and induced fracture through hydraulically stimulating the fracture. (SURF) in Lead, South Dakota. In situ tests are conducted in a 7.6 cm diameter and 100 long vertical borehole located in the 4850 Level West Access Drift near Davies Campus of SURF (Figure 1). The borehole is located in the zone of Precambrian Metamorphic Schist.

  20. The Research and Application of SURF Algorithm Based on Feature Point Selection Algorithm

    Directory of Open Access Journals (Sweden)

    Zhang Fang Hu

    2014-04-01

    Full Text Available As the pixel information of depth image is derived from the distance information, when implementing SURF algorithm with KINECT sensor for static sign language recognition, there can be some mismatched pairs in palm area. This paper proposes a feature point selection algorithm, by filtering the SURF feature points step by step based on the number of feature points within adaptive radius r and the distance between the two points, it not only greatly improves the recognition rate, but also ensures the robustness under the environmental factors, such as skin color, illumination intensity, complex background, angle and scale changes. The experiment results show that the improved SURF algorithm can effectively improve the recognition rate, has a good robustness.

  1. A Novel Image Retrieval Based on Visual Words Integration of SIFT and SURF.

    Directory of Open Access Journals (Sweden)

    Nouman Ali

    Full Text Available With the recent evolution of technology, the number of image archives has increased exponentially. In Content-Based Image Retrieval (CBIR, high-level visual information is represented in the form of low-level features. The semantic gap between the low-level features and the high-level image concepts is an open research problem. In this paper, we present a novel visual words integration of Scale Invariant Feature Transform (SIFT and Speeded-Up Robust Features (SURF. The two local features representations are selected for image retrieval because SIFT is more robust to the change in scale and rotation, while SURF is robust to changes in illumination. The visual words integration of SIFT and SURF adds the robustness of both features to image retrieval. The qualitative and quantitative comparisons conducted on Corel-1000, Corel-1500, Corel-2000, Oliva and Torralba and Ground Truth image benchmarks demonstrate the effectiveness of the proposed visual words integration.

  2. Environmental Awareness of Surf Tourists: A Case Study in the Algarve

    Directory of Open Access Journals (Sweden)

    Fabia Frank

    2015-06-01

    Full Text Available Even though surf tourism in Portugal is an economic activity with a steady growth rate, there are not many assessment studies available. Using a survey undertaken in surf camps located in the Vila do Bispo County, this study aims to analyse the environmental awareness of surf tourists in the Algarve. Through the New Environmental Paradigm (NEP scale it is shown that the environmental attitudes of respondents are strongly pro-ecological but also reveal some anthropocentric aspects. Tourists were asked about their willingness to pay for an accommodation tax earmarked for environmental protection in the Algarve. The results show that the large majority (86% would be willing to pay, which indicates a high environmental awareness. It is also found that the willingness to pay is related to the nationality, with respondents from Germany, Austria and Switzerland showing a higher willingness to pay.

  3. High resolution satellite image indexing and retrieval using SURF features and bag of visual words

    Science.gov (United States)

    Bouteldja, Samia; Kourgli, Assia

    2017-03-01

    In this paper, we evaluate the performance of SURF descriptor for high resolution satellite imagery (HRSI) retrieval through a BoVW model on a land-use/land-cover (LULC) dataset. Local feature approaches such as SIFT and SURF descriptors can deal with a large variation of scale, rotation and illumination of the images, providing, therefore, a better discriminative power and retrieval efficiency than global features, especially for HRSI which contain a great range of objects and spatial patterns. Moreover, we combine SURF and color features to improve the retrieval accuracy, and we propose to learn a category-specific dictionary for each image category which results in a more discriminative image representation and boosts the image retrieval performance.

  4. Heart Rate Responses of High School Students Participating in Surfing Physical Education.

    Science.gov (United States)

    Bravo, Michelle M; Cummins, Kevin M; Nessler, Jeff A; Newcomer, Sean C

    2016-06-01

    Despite the nation's rising epidemic of childhood obesity and diabetes, schools struggle to promote physical activities that help reduce risks for cardiovascular disease. Emerging data suggest that adopting novel activities into physical education (PE) curriculum may serve as an effective strategy for increasing physical activity in children. The purpose of this investigation was to characterize activity in the water and heart rates (HRs) of high school students participating in surf PE courses. Twenty-four male (n = 20) and female (n = 4) high school students (mean age = 16.7 ± 1.0 years) who were enrolled in surf PE courses at 2 high schools participated in this investigation. Daily measurements of surfing durations, average HR, and maximum HR were made on the students with HR monitors (PolarFT1) over an 8-week period. In addition, HR and activity in the water was evaluated during a single session in a subset of students (n = 11) using a HR monitor (PolarRCX5) and a video camera (Canon HD). Activity and HR were synchronized and evaluated in 5-second intervals during data analyses. The average duration that PE students participated in surfing during class was 61.7 ± 1.0 minutes. Stationary, paddling, wave riding, and miscellaneous activities comprised 42.7 ± 9.5, 36.7 ± 7.9, 2.9 ± 1.4, and 17.8 ± 11.4 percent of the surf session, respectively. The average and maximum HRs during these activities were 131.1 ± 0.9 and 177.2 ± 1.0 b·min, respectively. These data suggest that high school students participating in surf PE attained HRs and durations that are consistent with recommendations with cardiovascular fitness and health. In the future, PE programs should consider incorporating other action sports into their curriculum to enhance cardiovascular health.

  5. SurF: an innovative framework in biosecurity and animal health surveillance evaluation.

    Science.gov (United States)

    Muellner, Petra; Watts, Jonathan; Bingham, Paul; Bullians, Mark; Gould, Brendan; Pande, Anjali; Riding, Tim; Stevens, Paul; Vink, Daan; Stärk, Katharina Dc

    2018-05-16

    Surveillance for biosecurity hazards is being conducted by the New Zealand Competent Authority, the Ministry for Primary Industries (MPI) to support New Zealand's biosecurity system. Surveillance evaluation should be an integral part of the surveillance life cycle, as it provides a means to identify and correct problems and to sustain and enhance the existing strengths of a surveillance system. The surveillance evaluation Framework (SurF) presented here was developed to provide a generic framework within which the MPI biosecurity surveillance portfolio, and all of its components, can be consistently assessed. SurF is an innovative, cross-sectoral effort that aims to provide a common umbrella for surveillance evaluation in the animal, plant, environment and aquatic sectors. It supports the conduct of the following four distinct components of an evaluation project: (i) motivation for the evaluation, (ii) scope of the evaluation, (iii) evaluation design and implementation and (iv) reporting and communication of evaluation outputs. Case studies, prepared by MPI subject matter experts, are included in the framework to guide users in their assessment. Three case studies were used in the development of SurF in order to assure practical utility and to confirm usability of SurF across all included sectors. It is anticipated that the structured approach and information provided by SurF will not only be of benefit to MPI but also to other New Zealand stakeholders. Although SurF was developed for internal use by MPI, it could be applied to any surveillance system in New Zealand or elsewhere. © 2018 2018 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

  6. SURF: Taking Sustainable Remediation from Concept to Standard Operating Procedure (Invited)

    Science.gov (United States)

    Smith, L. M.; Wice, R. B.; Torrens, J.

    2013-12-01

    Over the last decade, many sectors of industrialized society have been rethinking behavior and re-engineering practices to reduce consumption of energy and natural resources. During this time, green and sustainable remediation (GSR) has evolved from conceptual discussions to standard operating procedure for many environmental remediation practitioners. Government agencies and private sector entities have incorporated GSR metrics into their performance criteria and contracting documents. One of the early think tanks for the development of GSR was the Sustainable Remediation Forum (SURF). SURF brings together representatives of government, industry, consultancy, and academia to parse the means and ends of incorporating societal and economic considerations into environmental cleanup projects. Faced with decades-old treatment programs with high energy outputs and no endpoints in sight, a small group of individuals published the institutional knowledge gathered in two years of ad hoc meetings into a 2009 White Paper on sustainable remediation drivers, practices, objectives, and case studies. Since then, SURF has expanded on those introductory topics, publishing its Framework for Integrating Sustainability into Remediation Projects, Guidance for Performing Footprint Analyses and Life-Cycle Assessments for the Remediation Industry, a compendium of metrics, and a call to improve the integration of land remediation and reuse. SURF's research and members have also been instrumental in the development of additional guidance through ASTM International and the Interstate Technology and Regulatory Council. SURF's current efforts focus on water reuse, the international perspective on GSR (continuing the conversations that were the basis of SURF's December 2012 meeting at the National Academy of Sciences in Washington, DC), and ways to capture and evaluate the societal benefits of site remediation. SURF also promotes and supports student chapters at universities across the US

  7. Run-up of tsunamis and long waves in terms of surf-similarity

    DEFF Research Database (Denmark)

    Madsen, Per A.; Fuhrman, David R.

    2008-01-01

    of the surf-similarity parameter and the amplitude to depth ratio determined at some offshore location. We use the analytical expressions to analyze the impact of tsunamis on beaches and relate the discussion to the recent Indian Ocean tsunami from December 26, 2004. An important conclusion is that extreme...... run-up combined with extreme flow velocities occurs for surf-similarity parameters of the order 3-6, and for typical tsunami wave periods this requires relatively mild beach slopes. Next, we compare the theoretical solutions to measured run-up of breaking and non-breaking irregular waves on steep...

  8. A Preliminary Assessment of the SURF Reactive Burn Model Implementation in FLAG

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Carl Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); McCombe, Ryan Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Carver, Kyle [United States Air Force, Washington, DC (United States)

    2017-09-18

    Properly validated and calibrated reactive burn models (RBM) can be useful engineering tools for assessing high explosive performance and safety. Experiments with high explosives are expensive. Inexpensive RBM calculations are increasingly relied on for predictive analysis for performance and safety. This report discusses the validation of Menikoff and Shaw’s SURF reactive burn model, which has recently been implemented in the FLAG code. The LANL Gapstick experiment is discussed as is its’ utility in reactive burn model validation. Data obtained from pRad for the LT-63 series is also presented along with FLAG simulations using SURF for both PBX 9501 and PBX 9502. Calibration parameters for both explosives are presented.

  9. COMPETING FOR WAVES: THE UNJUST REALITY OF WOMEN´S POSITION IN THE WORLD OF SURFING

    OpenAIRE

    İNCE YENİLMEZ, Meltem; ÇELİK, Onur Burak

    2017-01-01

    Throughout the years, women have suffered from oppression delivered by the male chauvinism. This maltreatment was present in every aspect of life, and surf was no exception. Since surfing has existed, it has been thought to be a sport just for men. Has this misconception driven women to avoid the sport at all costs for several years and dedicate themselves to completely different activities? This paper will provide an insight on the evolution of women´s role in this sport. Moreover, the situa...

  10. Smelting reduction of MgO in molten slag by liquid ferrosilicon

    Directory of Open Access Journals (Sweden)

    Tang, Qifeng

    2016-06-01

    Full Text Available The smelting reduction of magnesium oxide was researched in this paper. The effect of molten slag composition and reduction temperature on percent reduction of magnesium oxide were discussed, and kinetics of smelting reduction of magnesium oxide in molten slag was studied. The results showed that the reduction extent of magnesium oxide increased by increasing either one of the following factors: the initial mass ratio of Al2O3/SiO2, the addition of CaF2, the initial molar ratio of Si/2MgO, and reaction temperature. The overall smelting reduction was controlled by mass transfer in slag with an apparent activation energy 586 kJ mol-1.En este trabajo se estudia la reducción de óxido de magnesio. La influencia de la composición de las escorias y de la temperatura de reducción sobre el porcentaje de reducción de óxido de magnesio han sido discutidas, y asimismo se ha estudiado la cinética de la reducción del óxido de magnesio en escorias fundidas. Los resultados muestran que la reducción se incrementa al aumentar alguno de los siguientes factores: la proporción de Al2O3/SiO2, la adición de CaF2, la proporción molar de Si/2MgO y la temperatura de reacción. En general la reducción fue controlada por la transferencia de masa en la escoria con una energía aparente de 586 kJ mol-1.

  11. Thallium transformation and partitioning during Pb-Zn smelting and environmental implications.

    Science.gov (United States)

    Liu, Juan; Wang, Jin; Chen, Yongheng; Xie, Xiaofan; Qi, Jianying; Lippold, Holger; Luo, Dinggui; Wang, Chunlin; Su, Longxiao; He, Lucheng; Wu, Qiwei

    2016-05-01

    Thallium (Tl) is a toxic and non-essential heavy metal. Raw Pb-Zn ores and solid smelting wastes from a large Pb-Zn smelting plant - a typical thallium (Tl) pollution source in South China, were investigated in terms of Tl distribution and fractionation. A modified IRMM (Institute for Reference Materials and Measurement, Europe) sequential extraction scheme was applied on the samples, in order to uncover the geochemical behavior and transformation of Tl during Pb-Zn smelting and to assess the potential environmental risk of Tl arising from this plant. Results showed that the Pb-Zn ore materials were relatively enriched with Tl (15.1-87.7 mg kg(-1)), while even higher accumulation existed in the electrostatic dust (3280-4050 mg kg(-1)) and acidic waste (13,300 mg kg(-1)). A comparison of Tl concentration and fraction distribution in different samples clearly demonstrated the significant role of the ore roasting in Tl transformation and mobilization, probably as a result of alteration/decomposition of related minerals followed by Tl release and subsequent deposition/co-precipitation on fine surface particles of the electrostatic dust and acidic waste. While only 10-30% of total Tl amounts was associated with the exchangeable/acid-extractable fraction of the Pb-Zn ore materials, up to 90% of total Tl was found in this fraction of the electrostatic dust and acidic waste. Taking into account the mobility and bioavailability of this fraction, these waste forms may pose significant environmental risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Environmental impact of early Basque mining and smelting recorded in a high ash minerogenic peat deposit

    International Nuclear Information System (INIS)

    Monna, F.; Galop, D.; Carozza, L.; Tual, M.; Beyrie, A.; Marembert, F.; Chateau, C.; Dominik, J.; Grousset, F.E.

    2004-01-01

    More than four metres of core, covering almost 5000 years of deposition, were collected in a high ash minerogenic peat deposit located in the High Aldudes valley (Basque country), an area well known for its mineral abundance, exploited from Roman Times at least. Although minerogenic peatlands are not generally considered as the best archives to reconstruct past atmospheric metal deposition history, lead isotopic geochemistry demonstrates the integrity of the Pb record at least within the three upper meters; that is to say over the last four millennia. Zn, Cd and Cu may have been widely redistributed either by biological cycling, advective groundwater movements, or diffusional processes. Anthropogenic lead input phases are clearly pinpointed by positive shifts in Pb/Sc ratios with concomitant sharp drops in 206 Pb/ 207 Pb ratios. They are often accompanied by significant declines in tree taxa, interpreted as increasing demand for wood to supply energy for local mining and/or metallurgical operations. Periods of mining and/or smelting activity are identified during Antiquity and Modern Times, and are also confirmed by textual and field evidence. Inputs from the Rio Tinto (Southern Spain), often invoked as a major lead contributor to the European atmosphere during Roman Times, were not detected here. This remote source was probably masked by local inputs. Other mining and/or smelting phases, only suspected by archaeologists, are here identified as early as the Bronze Age. Although the durations of these phases are possibly overestimated because of detrital inputs consequent to the release of lead from polluted soils over a long period of time after major pollutant inputs, the periods at which pollution peaks occur are in good agreement with archaeological knowledge and palaeo-botanical data. The combination of geochemical and palaeo-botanical techniques with field archaeology, therefore provides a powerful tool in studying the interaction of early human societies with

  13. Distinguishing between native and smelted coppers using PIXE spectrometry: a case history from early colonial America

    International Nuclear Information System (INIS)

    Fleming, S.J.; Swann, C.P.

    2000-01-01

    During the recent excavation of a native American village at Governor's Land, in Virginia, two burials were unearthed, each of which contained a jumble of human bones, some fabric and a large number of copper tube beads. PIXE analysis of a representative group of these beads showed that about one-third of them were shaped from pieces of native copper, while the remainder were fashioned from scraps of smelted copper. Since the latter must have come from Europe, these data place the village's occupation in the decade either side of A.D. 1607, when the English first settled at nearby Jamestown

  14. Reduction electric smelting of ferriferrous-titanium concentrates from Gremyakha-Vyrmes deposit

    International Nuclear Information System (INIS)

    Morozov, A.A.

    2002-01-01

    Substantial composition of ilmenite and titanium-magnetite concentrates from Gremyaha-Vyrmes deposit is studied and their reducibility is examined as compared with other similar kids of raw materials. Thermal-physical properties of slag melts (such as toughness and melting ability), formed in reduction smelting of the above-mentioned concentrates for different reduction degree, are determined. These properties characterize the electric thermal transformation process of concentrates as hi-tech one. Features of chemical composition of metal, which is naturally alloyed with vanadium and is produced at the same time are noted. This metal expands the possibilities of complex used of the concentrates of this deposit [ru

  15. Fate of recovery boiler smelt nitrogen in the recovery cycle; Soodakattilan sulan typpiyhdisteitten kaeyttaeytyminen talteenottoprosessissa

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Forssen, M.; Backman, R.; Ek, P.; Hulden, S.G.; Kilpinen, P.; Kymaelaeinen, M.; Malm, H. [Aabo Akademi, Turku (Finland). Combustion Chemistry Research Group

    1997-10-01

    The purpose of this project is to study the fate of the nitrogen bound in the inorganic smelt after it enters the dissolving tank. Of special interest is to find in what form this nitrogen can be found further down in the recovery process and especially in what form it can be removed from the process. The aim is to clarify if the nitrogen can be a potential problem in the process or if it can become a potential emission. The work is divided into choosing methods for the analysis of different nitrogen species, collection and analysis of mill samples, laboratory studies and theoretical studies on nitrogen chemistry in alkaline solutions and reporting

  16. Pressure Gradients in the Inner Surf and Outer Swash Zone

    Science.gov (United States)

    Kidwell, A.; Puleo, J. A.; Torres-Freyermuth, A.

    2010-12-01

    The swash zone is a highly dynamic region of the beach profile. Although there has been significant progression in understanding the complex hydrodynamics of the swash zone, an improvement in the understanding of the sediment transport mechanisms deserves further investigation. Prior studies have demonstrated that the existing formulations derived from the energetics-type formulation do not accurately and consistently predict sediment transport. Thus, measurements and numerical modeling can contribute in the improvement of the current predictive capability of sediment transport. A potential enhancement to nearshore sediment transport is the horizontal pressure gradient. However, measuring the dynamic pressure gradient in nearshore flows is a difficult task. For instance, standard pressure sensors are generally ill-suited for this type of measurement in shallow swash flows due to the obstructing size of the sensor and the potential for flow interference. With improved measurement apparati and techniques, it is possible to obtain measurements of the horizontal pressure gradient. Our current research includes laboratory and numerical model investigation of the horizontal pressure gradient in the inner surf and outer swash zone. An inexpensive differential pressure gauge is employed allowing for a pressure port on the order of 2 mm diameter. Four pressure sensor pairs are installed 1 cm above the bed with a cross-shore spacing of 8 cm. The sensors are deployed just outside of and at various locations within the outer swash zone to determine spatio-temporal pressure variations. The measurement of total pressure coupled with the corresponding free surface measurements from co-located capacitance wave gauges yields time series of the hydrostatic and dynamic pressure and pressure gradients. A VOF-type RANS model is employed in this investigation. Firstly, the numerical model is validated with swash measurements. Then, model simulations will be performed in order to

  17. Cold-rolled sheets production of stainless martensite-ageing steel smelted by vacuum arc and electroslag techniques

    Energy Technology Data Exchange (ETDEWEB)

    Rivkin, A A; Grishkov, A I; Suslin, A P; Nesterenko, A A; Lola, V N [Tsentral' nyj Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii, Moscow (USSR)

    1975-05-01

    In cooperation with a number of metallurgical works the production of a high strength sheet stainless maraging steel EHP678 (000KH11N10M2T) has been tested by rolling cylindrical ingots of vacuum arc smelting at the blooming (the mass of rough ingots was 5.1 to 6.0 t, that of cleaned ingots - 3.8 to 5.1 t) or rectangular ingots of electroslag smelting (13 t) at the slabbing. The recommended regimes of heating and deformation are much similar to those used for the steel-KH18N10T. The output of valid cold-rolled sheets proved to be rather low (0.24 t/t for the vacuum arc smelting and 0.30 t/t for the electroslag smelting) mainly due to the losses on cleaning and a considerable portion of wrong-size slabs. The data are presented on the steel-EHP678 properties after various heat treatments. For the production of wide cold-rolled sheets of the steel EHP678 it is recommended to use steelmaking procedure with electroslag smelting including open-hearth melting in arc furnaces, rolling of ingots at the slabbing with heating up to 1260-1280 deg C (hold-up of 4.5 to 5 hrs); electroslag smelting for rectangular section slabs, rolling of ingots of electroslag smelting at the slabbing with their heating up to 1250 deg C (hold-up of 5.5 to 6 hrs), rolling at the 1680-type mill with heating up to 1250-1260 deg C (hold-up of 4 to 4.5 hrs ensuring the rolling temperature after a rough group not below 1100 deg C), quenching of hot-rolled sheets heating up to 920-940 deg C (hold-up of 3 to 3.5 min/mm), shot peening of sheets for descaling (provided the respective equipment is available) with a subsequent short-time pickling in an acid solution and cold rolling with a summary deformation of 35 to 45 %. The steelmaking with the electroslag smelting is much more profitable as regards to the fine technology of number of the main procedures, convenient cooperation of the works and a considerably greater output of the final products out of one ton of the steel produced.

  18. Sodium Silicate Gel Effect on Cemented Tailing Backfill That Contains Lead-Zinc Smelting Slag at Early Ages

    OpenAIRE

    Guo, Lijie; Li, Wenchen; Yang, Xiaocong; Xu, Wenyuan

    2018-01-01

    This paper presents the results of an experimental study on the priming effect of sodium silicate gel (SS) on cemented tailing backfill (CTB) that contains lead-zinc smelting slag. CTB and cemented paste (CP) containing lead-zinc smelting slag samples with SS of 0 and 0.4% of the mass of the slag were prepared and cured at 20°C for 1, 3, 7, and 28 days. Mechanical test and pore structure analyses were performed on the studied CTB samples, microstructural analyses (X-ray diffraction analysis a...

  19. Successional change in the Lake Superior fish community: population trends in ciscoes, rainbow smelt, and lake trout, 1958-2008

    Science.gov (United States)

    Gorman, Owen T.

    2012-01-01

    The Lake Superior fish community underwent massive changes in the second half of the 20th century. Those changes are largely reflected in changes in abundance of the adults of principal prey species, the ciscoes (Coregonus spp.), the invasive rainbow smelt (Osmerus mordax), and the principal predator, lake trout (Salvelinus namaycush). To better understand changes in species abundances, a comprehensive series of gillnet and bottom trawl data collected from 1958 to 2008 were examined. In the late 1950s/early 1960s, smelt abundance was at its maximum, wild lake trout was at its minimum, and an abundance of hatchery lake trout was increasing rapidly. The bloater (Coregonus hoyi) was the prevalent cisco in the lake; abundance was more than 300% greater than the next most abundant cisco, shortjaw cisco (C. zenithicus), followed by kiyi (C. kiyi) and lake cisco (C. artedi). By the mid-1960s, abundance of hatchery lake trout was nearing maximum, smelt abundance was beginning to decline, and abundances of all ciscoes declined, but especially that of shortjaw cisco and kiyi. By the late 1970s, recovery of wild lake trout stocks was well underway and abundances of hatchery lake trout and smelt were declining and the ciscoes were reaching their nadir. During 1980–1990, the fish community underwent a dramatic shift in organization and structure. The rapid increase in abundance of wild lake trout, concurrent with a rapid decline in hatchery lake trout, signaled the impending recovery. Rainbow smelt abundance dropped precipitously and within four years, lake cisco and bloater populations rebounded on the heels of a series of strong recruitment events. Kiyi populations showed signs of recovery by 1989, and shortjaw by 2000, though well below historic maximum abundances. High abundance of adult smelt prior to 1980 appears to be the only factor linked to recruitment failure in the ciscoes. Life history traits of the cisco species were examined to better understand their different

  20. Field Observations of Surf Zone-Inner Shelf Exchange on a Rip-Channeled Beach

    NARCIS (Netherlands)

    Brown, J.A.; MacMahan, J.H.; Reniers, A.J.H.M.; Thornton, E.B.

    2015-01-01

    Cross-shore exchange between the surf zone and the inner shelf is investigated using Lagrangian and Eulerian field measurements of rip current flows on a rip-channeled beach in Sand City, California. Surface drifters released on the inner shelf during weak wind conditions moved seaward due to rip

  1. Surf zone fish diet as an indicator of environmental and anthropogenic influences

    Science.gov (United States)

    Costa, Leonardo Lopes; Zalmon, Ilana Rosental

    2017-10-01

    Changes in species' abundance have been used as indicators of environmental and anthropogenic disturbances. However, sublethal, e.g., diet, changes should be detected before some alterations in the composition and structure of fish assemblages occur as a result of ecological negative impacts. The objective of the present study was to assess possible changes in surf zone fish diet in response to environmental and anthropogenic disturbances. Surf zone fish were sampled and their stomach contents were analyzed on two sandy beaches under different levels of human pressure in Southeastern Brazil. Habitat variables related to seasonality, food availability, anthropogenic disturbance, upwelling and river influence were measured as follows: (1) wave height; (2) water temperature; (3) intertidal macroinvertebrates abundance; (4) solid waste amount; (5) salinity; (6) particulate organic carbon (POC) and (7) chlorophyll a (Chl a). Our results showed the influence of seasonality, prey abundance and hydrodynamics in prey selection, and diet overlap between typical surf zone residents. A literature search was also performed and it shows that insects and Emerita brasiliensis eggs, which were the main food item consumed by some surf zone fish at urbanized Brazilian beaches, are unusual worldwide. Furthermore, solid waste was related to high consumption of insects by pompanos fish in urbanized areas, suggesting that this fish diet could be a sublethal indicator of human impact on sandy beaches.

  2. A generative Bezier curve model for surf-zone tracking in coastal image sequences

    CSIR Research Space (South Africa)

    Burke, Michael G

    2017-09-01

    Full Text Available This work introduces a generative Bezier curve model suitable for surf-zone curve tracking in coastal image sequences. The model combines an adaptive curve parametrised by control points governed by local random walks with a global sinusoidal motion...

  3. The effects of surfing and the natural environment on the well-being of combat veterans.

    Science.gov (United States)

    Caddick, Nick; Smith, Brett; Phoenix, Cassandra

    2015-01-01

    Although researchers have identified the benefits of physical activity on well-being, there is little evidence concerning the effects of nature-based physical activity. We investigated the effect of one nature-based activity-surfing-on the well-being of combat veterans experiencing posttraumatic stress disorder (PTSD). We conducted interviews and participant observations with a group of combat veterans belonging to a United Kingdom-based veterans' surfing charity. Our primary analytical approach was dialogical narrative analysis. Based on our rigorous analysis and findings, we suggest that surfing facilitated a sense of respite from PTSD. Respite was a fully embodied feeling of release from suffering that was cultivated through surfing and shaped by the stories veterans told of their experiences. We significantly extend previous knowledge on physical activity, combat veterans, and PTSD by highlighting how nature-based physical activity, encapsulated in the conceptual notion of the "blue gym," can promote well-being among combat veterans. © The Author(s) 2014.

  4. The Ocean as a Unique Therapeutic Environment: Developing a Surfing Program

    Science.gov (United States)

    Clapham, Emily D.; Armitano, Cortney N.; Lamont, Linda S.; Audette, Jennifer G.

    2014-01-01

    Educational aquatic programming offers necessary physical activity opportunities to children with disabilities and the benefits of aquatic activities are more pronounced for children with disabilities than for their able-bodied peers. Similar benefits could potentially be derived from surfing in the ocean. This article describes an adapted surfing…

  5. Study on Low Illumination Simultaneous Polarization Image Registration Based on Improved SURF Algorithm

    Science.gov (United States)

    Zhang, Wanjun; Yang, Xu

    2017-12-01

    Registration of simultaneous polarization images is the premise of subsequent image fusion operations. However, in the process of shooting all-weather, the polarized camera exposure time need to be kept unchanged, sometimes polarization images under low illumination conditions due to too dark result in SURF algorithm can not extract feature points, thus unable to complete the registration, therefore this paper proposes an improved SURF algorithm. Firstly, the luminance operator is used to improve overall brightness of low illumination image, and then create integral image, using Hession matrix to extract the points of interest to get the main direction of characteristic points, calculate Haar wavelet response in X and Y directions to get the SURF descriptor information, then use the RANSAC function to make precise matching, the function can eliminate wrong matching points and improve accuracy rate. And finally resume the brightness of the polarized image after registration, the effect of the polarized image is not affected. Results show that the improved SURF algorithm can be applied well under low illumination conditions.

  6. Deleterious mutations can surf to high densities on the wave front of an expanding population.

    Science.gov (United States)

    Travis, Justin M J; Münkemüller, Tamara; Burton, Olivia J; Best, Alex; Dytham, Calvin; Johst, Karin

    2007-10-01

    There is an increasing recognition that evolutionary processes play a key role in determining the dynamics of range expansion. Recent work demonstrates that neutral mutations arising near the edge of a range expansion sometimes surf on the expanding front leading them rather than that leads to reach much greater spatial distribution and frequency than expected in stationary populations. Here, we extend this work and examine the surfing behavior of nonneutral mutations. Using an individual-based coupled-map lattice model, we confirm that, regardless of its fitness effects, the probability of survival of a new mutation depends strongly upon where it arises in relation to the expanding wave front. We demonstrate that the surfing effect can lead to deleterious mutations reaching high densities at an expanding front, even when they have substantial negative effects on fitness. Additionally, we highlight that this surfing phenomenon can occur for mutations that impact reproductive rate (i.e., number of offspring produced) as well as mutations that modify juvenile competitive ability. We suggest that these effects are likely to have important consequences for rates of spread and the evolution of spatially expanding populations.

  7. Clay-oil flocculation during surf washing at the Sea Empress incident

    International Nuclear Information System (INIS)

    Wood, P.; Lunel, T.; Bailey, N.; Lee, K.

    1997-01-01

    Results of investigations into clay-oil flocculation during surf washing of oiled cobbles at Marros Beach, as a response to oiling during the Sea Empress incident, were summarized. Stranded oil on the cobble storm beach was found to associate with fine minerals and form flocs when introduced into sea water. The emulsions persisted for about 14 days after the oiling, after which it begun to disintegrate. After 50 days the remaining emulsion was found to be unstable and penetrated the beach to depths of up to three meters. Since no evidence of biodegradation was found during this period, oil reduction was attributed to sheening, facilitated by tidal fluctuations. Surf washing operation was undertaken over a seven day period beginning 47 days after the spill. Some 8150 tonnes of oiled cobbles were moved a distance of between 12 and 18 m seaward along a length of 850 m. Analysis of samples after two days following surf washing showed that oil concentration did not exceed 22 ppm, compared to 700 ppm before relocation. The significant reduction was considered to have been the result of enhanced oil dispersion coupled with the effects of the surf washing operations. 10 refs., 7 tabs., 10 figs

  8. Seabed Gradient Controlling Onshore Transport Rates of Surf Sand during Beach Retreat by Sea Level Rise

    Science.gov (United States)

    Lee, Hee Jun; Yi, Hi-Il

    2018-03-01

    A simple relationship is proposed for the onshore transport rates of surf-zone sand to evaluate the beach retreat caused by sea level rise. It suggests that the preservation potential of surf sand is proportional inversely to the seabed gradient during beach retreat. According to this relationship, the erosional remnants of surf sand would be more readily developed on a gentler shelf collectively as transgressive sand sheets. This finding may explain the previous studies regarding the Korean shelves that proposed that the Holocene transgressive sand sheets (HTSS) occur not in the steep eastern shelf but in the gentle western shelf. In line with such presence/absence of the HTSS are the results from some coastal seismic profiles obtained in the present study. The profiles indicate that sand deposits are restricted within the nearshore in the eastern coast, whereas they are persistently traceable to the offshore HTSS in the western coast. Tide is proven to have a negligible influence on the total duration of surf-zone processes. This study may be useful in predicting the consequences of the beach retreat that takes place worldwide as sea levels rise as a result of global warming.

  9. Investigation of the particulate derived from indigenous zinc smelting using the nuclear analytical technique

    International Nuclear Information System (INIS)

    Zhu Guanghua

    1995-12-01

    The air particulate samples at the site of indigenous zinc smelting in south of China, using an 8-stage cascade impactor have been collected. The elemental concentrations of the samples were analyzed by PIXE (Particle Induced X-ray Emission) method. As a result, the mass concentrations of more than 17 elements and their size distribution spectra were obtained. Then the data were analyzed by the absolute principal component analysis (APCA) to evaluate principal components and the percent variance explained by them. From the elemental size distribution spectra, three kinds of patterns were found that they corresponded to the tree principal components and suggested that they were from ore vapor, coal burning and soil dust. Based on the elemental size distribution spectra and a deposit model the deposited amounts for several elements in a human's lung during a day were calculated and compared with that of other places. It is shown that the air quality was heavily degraded at the site of indigenous zinc smelting. (5 refs., 3 figs., 2 tabs.)

  10. Modelling of chalcopyrite oxidation reactions in the Outokumpu flash smelting process

    Energy Technology Data Exchange (ETDEWEB)

    Ahokainen, T.; Jokilaakso, A. [Helsinki Univ. of Technology, Otaniemi (Finland)

    1996-12-31

    A mathematical model for simulating oxidation reactions of chalcopyrite particles together with momentum, heat and mass transfer between particle and gas phase in a flash smelting furnace reaction shaft is presented. In simulation, the equations governing the gas flow are solved numerically with a commercial fluid flow package, Phoenics. The particle phase is introduced into the gas flow by a Particle Source In Cell (PSIC) - technique, where a number of discrete particles is tracked in a gas flow and the relevant source terms for momentum, mass, and heat transfer are added to the gas phase equations. The gas phase equations used are elliptic in nature and the fluid turbulence is described by the (k-{epsilon}) -model. Thermal gas phase radiation is simulated with a six-flux radiation model. The chemical reactions of concentrate particles are assumed to happen at two sharp interfaces, and a shrinking core model is applied to describe the mass transfer of chemical species through the reaction product layer. In a molten state, the oxygen consumption is controlled by a film penetration concept. The reacting concentrate particles are a mixture of chalcopyrite and silica. Also a certain amount of pure inert silica is fed to the process as flux. In the simulations the calculation domain includes the concentrate burner and a cylindrical reaction shaft of an industrial scale flash smelting furnace. Some examples about the simulations carried out by the combustion model are presented. (author)

  11. Synthesis of cobalt alloy through smelting method and its characterization as prosthesis bone implant

    International Nuclear Information System (INIS)

    Aminatun,; Putri, N.S Efinda; Indriani, Arista; Himawati, Umi; Hikmawati, Dyah; Suhariningsih

    2014-01-01

    Cobalt-based alloys are widely used as total hip and knee replacements because of their excellent properties, such as corrosion resistance, fatigue strength and biocompatibility. In this work, cobalt alloys with variation of Cr (28.5; 30; 31.5; 33, and 34.5% wt) have been synthesized by smelting method began with the process of compaction, followed by smelting process using Tri Arc Melting Furnace at 200A. Continued by homogenization process at recrystallization temperature (1250° C) for 3 hours to allow the atoms diffuses and transform into γ phase. The next process is rolling process which is accompanied by heating at 1200° C for ± 15 minutes and followed by quenching. This process is repeated until the obtained thickness of ± 1 mm. The evaluated material properties included microstructure, surface morphology, and hardness value. It was shown that microstructure of cobalt alloys with variation of Cr is dominant by γ phase, thus making the entire cobalt alloys have high hardness. It was also shown from the surface morphology of entire cobalt alloys sample indicated the whole process of synthesis that had good solubility were at flat surface area. Hardness value test showed all of cobalt alloys sample had high hardness, just variation of 33% Cr be in the range of ASTMF75, it were 345,24 VHN which is potential to be applied as an implant prosthesis

  12. Smelting of high-quality boiler steel in large-load arc furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Kablukovskij, A F; Breus, V M; Tyurin, E I; Khristich, V D; Dumchev, Ya P [Tsentral' nyj Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii, Moscow (USSR)

    1975-02-01

    High-grade steel can be obtained in large-capacity furnaces if the smelting technology used takes account of the size of the aggregates, the course of the metal fusion process, interaction with slag, furnace atmosphere, reducing agents, and other process characteristics. 12Kh1MF boiler steel smelted in a 100-ton electric arc furnace by an oxidizing process with oxygen bath blow and cast by the siphon method into 6.5-ton ingots using a slag-forming mixture (240 mm diameter billets and 219 to 245 mm diameter tubes) is satisfactory with regard to macro and microstructure, oxygen and nonmetallic oxide inclusion content, and mechanical properties. The stress rupture strength of 10/sup 5/ h at 570/sup 0/C is similar to that of open-hearth steel. Sulfides larger than a 3.5 spheroid have been detected in it. The nitrogen content of the electric steel is 0.0090 to 0.0120%, which is somewhat greater than usual in open-hearth metal. Of the oxygen inclusions in the steel, spinel-alumina predominates. Large inclusions were represented mainly by brittle silicates which appeared to be of exogenous origin.

  13. Application of PAH concentration profiles in lake sediments as indicators for smelting activity.

    Science.gov (United States)

    Warner, Wiebke; Ruppert, Hans; Licha, Tobias

    2016-09-01

    The ability of lake sediment cores to store long-term anthropogenic pollution establishes them as natural archives. In this study, we focus on the influence of copper shale mining and smelting in the Mansfeld area of Germany, using the depth profiles of two sediment cores from Lake Süßer See. The sediment cores provide a detailed chronological deposition history of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in the studied area. Theisen sludge, a fine-grained residue from copper shale smelting, reaches the lake via deflation by wind or through riverine input; it is assumed to be the main source of pollution. To achieve the comparability of absolute contaminant concentrations, we calculated the influx of contaminants based on the sedimentation rate. Compared to the natural background concentrations, PAHs are significantly more enriched than heavy metals. They are therefore more sensitive and selective for source apportionment. We suggest two diagnostic ratios of PAHs to distinguish between Theisen sludge and its leachate: the ratio fluoranthene to pyrene ~2 and the ratio of PAH with logKOW5.7 converging to an even lower value than 2.3 (the characteristic of Theisen sludge) to identify the particulate input in lake environments. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Modelling of chalcopyrite oxidation reactions in the Outokumpu flash smelting process

    Energy Technology Data Exchange (ETDEWEB)

    Ahokainen, T; Jokilaakso, A [Helsinki Univ. of Technology, Otaniemi (Finland)

    1997-12-31

    A mathematical model for simulating oxidation reactions of chalcopyrite particles together with momentum, heat and mass transfer between particle and gas phase in a flash smelting furnace reaction shaft is presented. In simulation, the equations governing the gas flow are solved numerically with a commercial fluid flow package, Phoenics. The particle phase is introduced into the gas flow by a Particle Source In Cell (PSIC) - technique, where a number of discrete particles is tracked in a gas flow and the relevant source terms for momentum, mass, and heat transfer are added to the gas phase equations. The gas phase equations used are elliptic in nature and the fluid turbulence is described by the (k-{epsilon}) -model. Thermal gas phase radiation is simulated with a six-flux radiation model. The chemical reactions of concentrate particles are assumed to happen at two sharp interfaces, and a shrinking core model is applied to describe the mass transfer of chemical species through the reaction product layer. In a molten state, the oxygen consumption is controlled by a film penetration concept. The reacting concentrate particles are a mixture of chalcopyrite and silica. Also a certain amount of pure inert silica is fed to the process as flux. In the simulations the calculation domain includes the concentrate burner and a cylindrical reaction shaft of an industrial scale flash smelting furnace. Some examples about the simulations carried out by the combustion model are presented. (author)

  15. Thermodynamic Analysis of Oxygen-Enriched Direct Smelting of Jamesonite Concentrate

    Science.gov (United States)

    Zhang, Zhong-Tang; Dai, Xi; Zhang, Wen-Hai

    2017-12-01

    Thermodynamic analysis of oxygen-enriched direct smelting of jamesonite concentrate is reported in this article. First, the occurrence state of lead, antimony and other metallic elements in the smelting process was investigated theoretically. Then, the verification test was carried out. The results indicate that lead and antimony mainly exist in the alloy in the form of metallic lead and metallic antimony. Simultaneously, lead and antimony were also oxidized into the slag in the form of lead-antimony oxide. Iron and copper could be oxidized into the slag in the form of oxides in addition to combining with antimony in the alloy, while zinc was mainly oxidized into the slag in the form of zinc oxide. The verification test indicates that the main phases in the alloy contain metallic lead, metallic antimony and a small amount of Cu2Sb, FeSb2 intermetallic compounds, and the slag is mainly composed of kirschsteinite, fayalite and zinc oxide, in agreement with the thermodynamic analysis.

  16. Two-Dimensional Physical and CFD Modelling of Large Gas Bubble Behaviour in Bath Smelting Furnaces

    Directory of Open Access Journals (Sweden)

    Yuhua Pan

    2010-09-01

    Full Text Available The behaviour of large gas bubbles in a liquid bath and the mechanisms of splash generation due to gas bubble rupture in high-intensity bath smelting furnaces were investigated by means of physical and mathematical (CFD modelling techniques. In the physical modelling work, a two-dimensional Perspex model of the pilot plant furnace at CSIRO Process Science and Engineering was established in the laboratory. An aqueous glycerol solution was used to simulate liquid slag. Air was injected via a submerged lance into the liquid bath and the bubble behaviour and the resultant splashing phenomena were observed and recorded with a high-speed video camera. In the mathematical modelling work, a two-dimensional CFD model was developed to simulate the free surface flows due to motion and deformation of large gas bubbles in the liquid bath and rupture of the bubbles at the bath free surface. It was concluded from these modelling investigations that the splashes generated in high-intensity bath smelting furnaces are mainly caused by the rupture of fast rising large gas bubbles. The acceleration of the bubbles into the preceding bubbles and the rupture of the coalescent bubbles at the bath surface contribute significantly to splash generation.

  17. Exploring Critical Alternatives for Youth Development through Lifestyle Sport: Surfing and Community Development in Aotearoa/New Zealand

    Directory of Open Access Journals (Sweden)

    Belinda Wheaton

    2017-12-01

    Full Text Available While competition-based team sports remain dominant in community and sport-for-development programs, researchers are exploring the value of alternative, less “sportized” activities such as lifestyle/action sports. In this paper, we explore the ways in which surfing is being used in development programs in Aotearoa/New Zealand, examining the perceived social benefits and impact. Our methods involved: (a mapping the range of surfing projects; and (b 8 in-depth interviews with program personnel. Widespread conviction in the positive developmental benefits of surfing was evident, and that surfing had a “special” capacity to reform or heal those who participate in it. However, the ways in which individuals’ self-developments were promoted appear to be following the traditional sport/youth development path. They focus on policies aimed at improved life chances, equipping youth with the tools for self-improvement and self-management, inculcating self-governance and self-reliance. However, a counter narrative co-existed, highlighting surfing as a freeing experience, which, rather than restoring social order, works to instigate a personal transformation or awakening. Despite the range of challenges presented by surfing as a tool for positive development, surfing presents a potentially “critical alternative” which if sport-for-development programs are to be a form of social change, we should remain open to exploring.

  18. Identification of an evolutionary conserved SURF-6 domain in a family of nucleolar proteins extending from human to yeast

    International Nuclear Information System (INIS)

    Polzikov, Mikhail; Zatsepina, Olga; Magoulas, Charalambos

    2005-01-01

    The mammalian SURF-6 protein is localized in the nucleolus, yet its function remains elusive in the recently characterized nucleolar proteome. We discovered by searching the Protein families database that a unique evolutionary conserved SURF-6 domain is present in the carboxy-terminal of a novel family of eukaryotic proteins extending from human to yeast. By using the enhanced green fluorescent protein as a fusion protein marker in mammalian cells, we show that proteins from distantly related taxonomic groups containing the SURF-6 domain are localized in the nucleolus. Deletion sequence analysis shows that multiple regions of the SURF-6 protein are capable of nucleolar targeting independently of the evolutionary conserved domain. We identified that the Saccharomyces cerevisiae member of the SURF-6 family, named rrp14 or ykl082c, has been categorized in yeast databases to interact with proteins involved in ribosomal biogenesis and cell polarity. These results classify SURF-6 as a new family of nucleolar proteins in the eukaryotic kingdom and point out that SURF-6 has a distinct domain within the known nucleolar proteome that may mediate complex protein-protein interactions for analogous processes between yeast and mammalian cells

  19. ImageSURF: An ImageJ Plugin for Batch Pixel-Based Image Segmentation Using Random Forests

    Directory of Open Access Journals (Sweden)

    Aidan O'Mara

    2017-11-01

    Full Text Available Image segmentation is a necessary step in automated quantitative imaging. ImageSURF is a macro-compatible ImageJ2/FIJI plugin for pixel-based image segmentation that considers a range of image derivatives to train pixel classifiers which are then applied to image sets of any size to produce segmentations without bias in a consistent, transparent and reproducible manner. The plugin is available from ImageJ update site http://sites.imagej.net/ImageSURF/ and source code from https://github.com/omaraa/ImageSURF. Funding statement: This research was supported by an Australian Government Research Training Program Scholarship.

  20. Sampling uncharted waters: Examining rearing habitat of larval Longfin Smelt (Spirinchus thaleichthys) in the upper San Francisco Estuary

    Science.gov (United States)

    Grimaldo, Lenny; Feyrer, Frederick; Burns, Jillian; Maniscalco, Donna

    2017-01-01

    The southern-most reproducing Longfin Smelt population occurs in the San Francisco Estuary, California, USA. Long-term monitoring of estuarine habitat for this species has generally only considered deep channels, with little known of the role shallow waters play in supporting their early life stage. To address the need for focused research on shallow-water habitat, a targeted study of Longfin Smelt larvae in littoral habitat was conducted to identify potential rearing habitats during 2013 and 2014. Our study objectives were to (1) determine if larval densities vary between littoral habitats (tidal slough vs. open-water shoal), (2) determine how larval densities in littoral habitats vary with physicochemical and biological attributes, (3) determine if larval densities vary between littoral habitats and long-term monitoring channel collections, and (4) determine what factors predict larval rearing distributions from the long-term monitoring channel collections. Larval densities did not vary between littoral habitats but they did vary between years. Water temperature, salinity, and chlorophyll a were found important in predicting larval densities in littoral habitats. Larval densities do not vary between littoral and channel surveys; however, the analysis based on channel data suggests that Longfin Smelt are hatching and rearing in a much broader region and under higher salinities (∼2–12 psu) than previously recognized. Results of this study indicate that conservation efforts should consider how freshwater flow, habitat, climate, and food webs interact as mechanisms that influence Longfin Smelt recruitment in estuarine environments.

  1. The recovery of Zn and Pb and the manufacture of lightweight bricks from zinc smelting slag and clay.

    Science.gov (United States)

    Hu, Huiping; Deng, Qiufeng; Li, Chao; Xie, Yue; Dong, Zeqin; Zhang, Wei

    2014-04-30

    Novel lightweight bricks have been produced by sintering mixes of zinc smelting slag and clay. A two-stage sintered process has been proposed to recovery of Zn and Pb and reutilization of the zinc smelting slag. In the first stage of the process, called reduction and volatilization procedure, zinc and lead were reduced by the carbon contained in the zinc smelting slag and volatilized into the dust, and the dust can be used as a secondary zinc resource. In the second stage of the process, called oxidation sintering procedure, a lightweight brick was produced. Samples containing up to 60 wt.% zinc smelting slag and 40 wt.% kaolin clay were reduced at 1050°C for 6h, and then sintered at 1050°C for 4h. The recoveries of Zn and Pb from the brick are 94.5 ± 0.6% and 97.6 ± 0.2%, respectively. Low bulk density (1.42 g cm(-3)) and relatively high compressive strength (2 2MPa) sintered bricks were produced, and the leaching toxicity of the sintered bricks was below the regulatory thresholds of Chinese National Standards. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Karyotype and chromosomal characteristics of Ag-NOR sites and 5S rDNA in European smelt, Osmerus eperlanus

    Czech Academy of Sciences Publication Activity Database

    Ocalewicz, K.; Hliwa, P.; Krol, J.; Rábová, Marie; Stabinski, R.; Ráb, Petr

    2007-01-01

    Roč. 131, - (2007), s. 29-35 ISSN 0016-6707 R&D Projects: GA AV ČR IAA6045405; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z50450515 Keywords : chromosome banding * cytotaxonomy of smelt * fish cytogenetics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.396, year: 2007

  3. Trace element partitioning and soil particle characterisation around mining and smelting areas at Tharsis, Riotinto and Huelva, SW Spain

    Energy Technology Data Exchange (ETDEWEB)

    Chopin, E.I.B. [School of Human and Environmental Sciences, University of Reading (United Kingdom)]. E-mail: edith.chopin@univ-reims.fr; Alloway, B.J. [School of Human and Environmental Sciences, University of Reading (United Kingdom)

    2007-02-15

    Trace elements may present an environmental hazard in the vicinity of mining and smelting activities. However, the factors controlling trace element distribution in soils around ancient and modern mining and smelting areas are not always clear. Tharsis, Riotinto and Huelva are located in the Iberian Pyrite Belt in SW Spain. Tharsis and Riotinto mines have been exploited since 2500 B.C., with intensive smelting taking place. Huelva, established in 1970 and using the Flash Furnace Outokumpu process, is currently one of the largest smelter in the world. Pyrite and chalcopyrite ore have been intensively smelted for Cu. However, unusually for smelters and mines of a similar size, the elevated trace element concentrations in soils were found to be restricted to the immediate vicinity of the mines and smelters, being found up to a maximum of 2 km from the mines and smelters at Tharsis, Riotinto and Huelva. Trace element partitioning (over 2/3 of trace elements found in the residual immobile fraction of soils at Tharsis) and soil particles examination by SEM-EDX showed that trace elements were not adsorbed onto soil particles, but were included within the matrix of large trace element-rich Fe silicate slag particles (i.e. 1 mm o at least 1 wt.% As, Cu and Zn, and 2 wt.% Pb). Slag particle large size (1 mm o) was found to control the geographically restricted trace element distribution in soils at Tharsis, Riotinto and Huelva, since large heavy particles could not have been transported long distances. Distribution and partitioning indicated that impacts to the environment as a result of mining and smelting should remain minimal in the region.

  4. Polychlorinated dibenzo-p-dioxin and dibenzofuran and polychlorinated biphenyl emissions from different smelting stages in secondary copper metallurgy.

    Science.gov (United States)

    Hu, Jicheng; Zheng, Minghui; Nie, Zhiqiang; Liu, Wenbin; Liu, Guorui; Zhang, Bing; Xiao, Ke

    2013-01-01

    Secondary copper production has received much attention for its high emissions of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) reported in previous studies. These studies focused on the estimation of total PCDD/F and polychlorinated biphenyl (PCB) emissions from secondary copper smelters. However, large variations in PCDD/F and PCB emissions reported in these studies were not analyzed and discussed further. In this study, stack gas samples at different smelting stages (feeding-fusion, oxidation and deoxidization) were collected from four plants to investigate variations in PCDD/F and PCB emissions and characteristics during the secondary copper smelting process. The results indicate that PCDD/F emissions occur mainly at the feeding-fusion stage and these emissions contribute to 54-88% of the total emissions from the secondary copper smelting process. The variation in feed material and operating conditions at different smelting stages leads to the variation in PCDD/F emissions during the secondary copper smelting process. The total PCDD/F and PCB discharge (stack gas emission+fly ash discharge) is consistent with the copper scrap content in the raw material in the secondary copper smelters investigated. On a production basis of 1 ton copper, the total PCDD/F and dl-PCB discharge was 102, 24.8 and 5.88 μg TEQ t(-1) for the three plants that contained 100%, 30% and 0% copper scrap in their raw material feed, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Bubble Clouds and their Transport within the Surf Zone as Measured with a Distributed Array of Upward-Looking Sonars

    National Research Council Canada - National Science Library

    Dahl, Peter

    2000-01-01

    ... in the surf zone and the effects of these bubbles on acoustic propagation. This paper discusses data gathered by the Applied Physics Laboratory, University of Washington, using a set of four upward-looking sonars (frequency 240 kHz...

  6. Spatially Uniform ReliefF (SURF for computationally-efficient filtering of gene-gene interactions

    Directory of Open Access Journals (Sweden)

    Greene Casey S

    2009-09-01

    Full Text Available Abstract Background Genome-wide association studies are becoming the de facto standard in the genetic analysis of common human diseases. Given the complexity and robustness of biological networks such diseases are unlikely to be the result of single points of failure but instead likely arise from the joint failure of two or more interacting components. The hope in genome-wide screens is that these points of failure can be linked to single nucleotide polymorphisms (SNPs which confer disease susceptibility. Detecting interacting variants that lead to disease in the absence of single-gene effects is difficult however, and methods to exhaustively analyze sets of these variants for interactions are combinatorial in nature thus making them computationally infeasible. Efficient algorithms which can detect interacting SNPs are needed. ReliefF is one such promising algorithm, although it has low success rate for noisy datasets when the interaction effect is small. ReliefF has been paired with an iterative approach, Tuned ReliefF (TuRF, which improves the estimation of weights in noisy data but does not fundamentally change the underlying ReliefF algorithm. To improve the sensitivity of studies using these methods to detect small effects we introduce Spatially Uniform ReliefF (SURF. Results SURF's ability to detect interactions in this domain is significantly greater than that of ReliefF. Similarly SURF, in combination with the TuRF strategy significantly outperforms TuRF alone for SNP selection under an epistasis model. It is important to note that this success rate increase does not require an increase in algorithmic complexity and allows for increased success rate, even with the removal of a nuisance parameter from the algorithm. Conclusion Researchers performing genetic association studies and aiming to discover gene-gene interactions associated with increased disease susceptibility should use SURF in place of ReliefF. For instance, SURF should be

  7. Drones at the Beach - Surf Zone Monitoring Using Rotary Wing Unmanned Aerial Vehicles

    Science.gov (United States)

    Rynne, P.; Brouwer, R.; de Schipper, M. A.; Graham, F.; Reniers, A.; MacMahan, J. H.

    2014-12-01

    We investigate the potential of rotary wing Unmanned Aerial Vehicles (UAVs) to monitor the surf zone. In recent years, the arrival of lightweight, high-capacity batteries, low-power electronics and compact high-definition cameras has driven the development of commercially available UAVs for hobbyists. Moreover, the low operation costs have increased their potential for scientific research as these UAVs are extremely flexible surveying platforms. The UAVs can fly for ~12 min with a mean loiter radius of 1 - 3.5 m and a mean loiter error of 0.75 - 4.5 m, depending on the environmental conditions, flying style, battery type and vehicle type. Our experiments using multiple, alternating UAVs show that it is possible to have near continuous imagery data with similar Fields Of View. The images obtained from the UAVs (Fig. 1a), and in combination with surveyed Ground Control Points (GCPs) (Fig. 1b, red squares and white circles), can be geo-rectified (Fig. 1c) to pixel resolution between 0.01 - 1 m and a reprojection error, i.e. the difference between the surveyed GPS location of a GCP and the location of the GCP obtained from the geo-rectified image, of O(1 m). These geo-rectified images provide data on a variety of coastal aspects, such as beach width (Wb(x,t)), surf zone width (Wsf(x,t)), wave breaking location (rectangle B), beach usage (circle C) and location of dune vegegation (rectangle D), amongst others. Additionally, the possibility to have consecutive, high frequency (up to 2 Hz) rectified images makes the UAVs a great data instrument for spatially and temporally variable systems, such as the surf zone. Our first observations with the UAVs reveal the potential to quickly obtain surf zone and beach characteristics in response to storms or for day to day beach information, as well as the scientific pursuits of surf zone kinematics on different spatial and temporal scales, and dispersion and advection estimates of pollutants/dye. A selection of findings from

  8. Car surfing: an underreported mechanism of serious injury in children and adolescents.

    Science.gov (United States)

    Geiger, J D; Newsted, J; Drongowski, R A; Lelli, J L

    2001-01-01

    Car surfing, in which participants stand on top of a moving vehicle as though it were a surfboard, has been reported as a cause of traumatic injury in only 5 cases in the literature. Over the last 8 years, however, the authors have treated 26 children, primarily adolescents, for injuries resulting from car surfing. This report describes the injuries and outcomes of this potentially underreported mechanism of injury. Medical records of 26 patients treated for car surfing injuries between 1991 and 1999 were reviewed. Demographics, hospital course, and type and severity of injuries were analyzed. Eighteen boys (69%) and 8 girls (31%) with an average age of 15.7+/-3.4 years (range, 6 to 22) have presented with injuries related to car surfing. All patients had fallen from the hood, roof, or trunk of a moving motor vehicle, the majority falling from the hood (n = 13; 50%). Injury severity was evaluated using the Injury Severity Scores (ISS; 12.4+/-6.5), Revised Trauma Score (RTS; 7.5+/- 1.1) and Glasgow Coma Score (GCS; 13.5+/-3.2). Injury severity was equivalent between boys and girls (P>.05). Central nervous system injuries predominated, with closed head injuries occurring in 22 (85%) and loss of consciousness in 10 (39%). Skull fractures occurred in 11 (42%) and intracranial bleeding in 9 (35%). Long-term cognitive rehabilitation was necessary in 22 (85%) patients. Three patients (12%) had spinal column fractures, with 2 (8%) suffering permanent paralysis. Two extremity (8%) and 3 (11.7%) pelvic fractures occurred. Most patients (73%) suffered significant skin and soft tissue injuries. Two patients (8%) presented with solid visceral injuries, and 1 child died. Car surfing is an extremely high-risk behavior in children and adolescents that leads to significant morbidity, long-term disability, and is potentially fatal. The incidence of car surfing may be greater than has been reported previously; therefore, prevention programs aimed at discouraging this high

  9. Cytochrome C oxydase deficiency: SURF1 gene investigation in patients with Leigh syndrome.

    Science.gov (United States)

    Maalej, Marwa; Kammoun, Thouraya; Alila-Fersi, Olfa; Kharrat, Marwa; Ammar, Marwa; Felhi, Rahma; Mkaouar-Rebai, Emna; Keskes, Leila; Hachicha, Mongia; Fakhfakh, Faiza

    2018-03-18

    Leigh syndrome (LS) is a rare progressive neurodegenerative disorder occurring in infancy. The most common clinical signs reported in LS are growth retardation, optic atrophy, ataxia, psychomotor retardation, dystonia, hypotonia, seizures and respiratory disorders. The paper reported a manifestation of 3 Tunisian patients presented with LS syndrome. The aim of this study is the MT[HYPHEN]ATP6 and SURF1 gene screening in Tunisian patients affected with classical Leigh syndrome and the computational investigation of the effect of detected mutations on its structure and functions by clinical and bioinformatics analyses. After clinical investigations, three Tunisian patients were tested for mutations in both MT-ATP6 and SURF1 genes by direct sequencing followed by in silico analyses to predict the effects of sequence variation. The result of mutational analysis revealed the absence of mitochondrial mutations in MT-ATP6 gene and the presence of a known homozygous splice site mutation c.516-517delAG in sibling patients added to the presence of a novel double het mutations in LS patient (c.752-18 A > C/c. c.751 + 16G > A). In silico analyses of theses intronic variations showed that it could alters splicing processes as well as SURF1 protein translation. Leigh syndrome (LS) is a rare progressive neurodegenerative disorder occurring in infancy. The most common clinical signs reported in LS are growth retardation, optic atrophy, ataxia, psychomotor retardation, dystonia, hypotonia, seizures and respiratory disorders. The paper reported a manifestation of 3 Tunisian patients presented with LS syndrome. The aim of this study is MT-ATP6 and SURF1 genes screening in Tunisian patients affected with classical Leigh syndrome and the computational investigation of the effect of detected mutations on its structure and functions. After clinical investigations, three Tunisian patients were tested for mutations in both MT-ATP6 and SURF1 genes by direct sequencing followed by in

  10. Trace elements in rainwater and dry deposition around a smelting complex

    Energy Technology Data Exchange (ETDEWEB)

    Beavington, F

    1977-06-01

    A number of plastic raingauges were set up at various distances around a smelting complex (copper smelter and steelworks) in Wollongong, Australia, to determine the pattern of total atmospheric deposition (rainwater and dry deposition) of copper, zinc, lead, cadmium, iron and manganese. At the site nearest the smelter, total deposition of these metals (6N HCl soluble) in kg/ha over a period of twelve months was 30.7 copper, 8.4 zinc, 4.7 lead, 0.19 cadmium, 42.6 iron and 1.5 manganese. These levels were considerably higher than at a distant rural site where background levels were similar to those reported for the United Kingdom. The pattern of deposition of metals over Wollongong accords with levels of metals previously reported in surface soil, herbage and leaf vegetables.

  11. Lance for fuel and oxygen injection into smelting or refining furnace

    Science.gov (United States)

    Schlichting, Mark R.

    1994-01-01

    A furnace 10 for smelting iron ore and/or refining molten iron 20 is equipped with an overhead pneumatic lance 40, through which a center stream of particulate coal 53 is ejected at high velocity into a slag layer 30. An annular stream of nitrogen or argon 51 enshrouds the coal stream. Oxygen 52 is simultaneously ejected in an annular stream encircling the inert gas stream 51. The interposition of the inert gas stream between the coal and oxygen streams prevents the volatile matter in the coal from combusting before it reaches the slag layer. Heat of combustion is thus more efficiently delivered to the slag, where it is needed to sustain the desired reactions occurring there. A second stream of lower velocity oxygen can be delivered through an outermost annulus 84 to react with carbon monoxide gas rising from slag layer 30, thereby adding still more heat to the furnace.

  12. Statistical modeling of copper losses in the silicate slag of the sulfide concentrate smelting process

    Directory of Open Access Journals (Sweden)

    Savic Marija V.

    2015-09-01

    Full Text Available This article presents the results of the statistical modeling of copper losses in the silicate slag of the sulfide concentrates smelting process. The aim of this study was to define the correlation dependence of the degree of copper losses in the silicate slag on the following parameters of technological processes: SiO2, FeO, Fe3O4, CaO and Al2O3 content in the slag and copper content in the matte. Multiple linear regression analysis (MLRA, artificial neural networks (ANNs and adaptive network based fuzzy inference system (ANFIS were used as tools for mathematical analysis of the indicated problem. The best correlation coefficient (R2 = 0.719 of the final model was obtained using the ANFIS modeling approach.

  13. Composition, Shell Strength, and Metabolizable Energy of Mulinia lateralis and Ischadium recurvum as Food for Wintering Surf Scoters (Melanitta perspicillata.

    Directory of Open Access Journals (Sweden)

    Alicia M Wells-Berlin

    Full Text Available Decline in surf scoter (Melanitta perspicillata waterfowl populations wintering in the Chesapeake Bay has been associated with changes in the availability of benthic bivalves. The Bay has become more eutrophic, causing changes in the benthos available to surf scoters. The subsequent decline in oyster beds (Crassostrea virginica has reduced the hard substrate needed by the hooked mussel (Ischadium recurvum, one of the primary prey items for surf scoters, causing the surf scoter to switch to a more opportune species, the dwarf surfclam (Mulinia lateralis. The composition (macronutrients, minerals, and amino acids, shell strength (N, and metabolizable energy (kJ of these prey items were quantified to determine the relative foraging values for wintering scoters. Pooled samples of each prey item were analyzed to determine composition. Shell strength (N was measured using a shell crack compression test. Total collection digestibility trials were conducted on eight captive surf scoters. For the prey size range commonly consumed by surf scoters (6-12 mm for M. lateralis and 18-24 mm for I. recurvum, I. recurvum contained higher ash, protein, lipid, and energy per individual organism than M. lateralis. I. recurvum required significantly greater force to crack the shell relative to M. lateralis. No difference in metabolized energy was observed for these prey items in wintering surf scoters, despite I. recurvum's higher ash content and harder shell than M. lateralis. Therefore, wintering surf scoters were able to obtain the same amount of energy from each prey item, implying that they can sustain themselves if forced to switch prey.

  14. Exploring Critical Alternatives for Youth Development through Lifestyle Sport: Surfing and Community Development in Aotearoa/New Zealand

    OpenAIRE

    Belinda Wheaton; Georgina Roy; Rebecca Olive

    2017-01-01

    While competition-based team sports remain dominant in community and sport-for-development programs, researchers are exploring the value of alternative, less “sportized” activities such as lifestyle/action sports. In this paper, we explore the ways in which surfing is being used in development programs in Aotearoa/New Zealand, examining the perceived social benefits and impact. Our methods involved: (a) mapping the range of surfing projects; and (b) 8 in-depth interviews with program personne...

  15. Geochemical Study on an Abandoned Copper Smelting Plant Using Rare Earth Elements

    Science.gov (United States)

    Sun, S. H.

    2017-12-01

    The Shuei Nan Dong Copper Smelting Plant smelting is located on the northern coast of New Taipei City, Taiwan. The plant built in 1906 for but has been shut down since 1987. However, the watershed is continuing to discharge acid mine water into the sea; and, the acid mine drainage releases high amounts of sulfate, heavy metals without any treatment. In this study, the water samples were sequentially collected along the main channel and its tributaries in the watershed. The results of hydrochemical analysis show that the untreated inflow water can be characterized with low pH value of 80% of the total variance and almost all chemical components have high loadings in the PC. Therefore, the hydrochemical properties in the watershed are mainly dominated by the mixing process between main channel and the major tributary but the geochemical reactions during flow down the channel is insignificant. Rare earth elements (REE) are an excellent tracer, which can indicate sources of chemical components and geochemical reactions in water. The analysis results demonstrate two distinct REE patterns. The water with low REE can be characterized by prominent Eu positive anomaly and Ce negative anomaly, which may result from the alteration of Na-plagioclase in sandstone and oxidation reaction when contact with air, respectively. On the contrary, the water with high REE shows only minor Ce negative anomaly and insignificant Eu positive anomaly. In addition, there is an enrichment of middle REE in high-REE water, which is quite different with the REE pattern of pyrite. According to the Grawunder's study (2014), it corresponds to the complexation to sulphite during pyrite oxidation. It is worth noting that REE show no considerable fractionation along the channel and confirms the results from PCA. It can be derived that the water may not reached equilibrium condition. A simple aerated retention pool could dramatically reduce the pollutants due to coprecipitation of iron oxide and aluminum

  16. Decreased in vitro mitochondrial function is associated with enhanced brain metabolism, blood flow, and memory in Surf1-deficient mice

    Science.gov (United States)

    Lin, Ai-Ling; Pulliam, Daniel A; Deepa, Sathyaseelan S; Halloran, Jonathan J; Hussong, Stacy A; Burbank, Raquel R; Bresnen, Andrew; Liu, Yuhong; Podlutskaya, Natalia; Soundararajan, Anuradha; Muir, Eric; Duong, Timothy Q; Bokov, Alex F; Viscomi, Carlo; Zeviani, Massimo; Richardson, Arlan G; Van Remmen, Holly; Fox, Peter T; Galvan, Veronica

    2013-01-01

    Recent studies have challenged the prevailing view that reduced mitochondrial function and increased oxidative stress are correlated with reduced longevity. Mice carrying a homozygous knockout (KO) of the Surf1 gene showed a significant decrease in mitochondrial electron transport chain Complex IV activity, yet displayed increased lifespan and reduced brain damage after excitotoxic insults. In the present study, we examined brain metabolism, brain hemodynamics, and memory of Surf1 KO mice using in vitro measures of mitochondrial function, in vivo neuroimaging, and behavioral testing. We show that decreased respiration and increased generation of hydrogen peroxide in isolated Surf1 KO brain mitochondria are associated with increased brain glucose metabolism, cerebral blood flow, and lactate levels, and with enhanced memory in Surf1 KO mice. These metabolic and functional changes in Surf1 KO brains were accompanied by higher levels of hypoxia-inducible factor 1 alpha, and by increases in the activated form of cyclic AMP response element-binding factor, which is integral to memory formation. These findings suggest that Surf1 deficiency-induced metabolic alterations may have positive effects on brain function. Exploring the relationship between mitochondrial activity, oxidative stress, and brain function will enhance our understanding of cognitive aging and of age-related neurologic disorders. PMID:23838831

  17. Characterization of breeding habitats for black and surf scoters in the eastern boreal forest and subarctic regions of Canada

    Science.gov (United States)

    Perry, M.C.; Kidwell, D.M.; Wells, A.M.; Lohnes, E.J.R.; Osenton, P.C.; Altmann, S.H.; Hanson, Alan; Kerekes, Joseph; Paquet, Julie

    2006-01-01

    We analyzed characteristics of wetland habitats used by breeding black scoters (Melanitta nigra) and surf scoters (M. perspicillata) in the eastern boreal forest and subarctic regions of Canada based on satellite telemetry data collected in the spring and summer. During 2002 and 2004, nine black scoters (four males, five females) were tracked to breeding areas in Quebec, Manitoba, and Northwest Territories. In addition, in 2001?04, seven surf scoters (three males, four females) were tracked to breeding areas in Labrador, Quebec, Northwest Territories, and Nunavut. Based on satellite telemetry data, locations of black and surf scoters in breeding areas were not significantly different in regard to latitude and longitude. Presumed breeding areas were manually plotted on topographic maps and percent cover type and water were estimated. Breeding habitat of black scoters was significantly different than that for surf scoters, with black scoters mainly using open (tundra) areas (44%) and surf scoters using mainly forest areas (66%). Surf scoters presumed breeding areas were at significantly higher elevations than areas used by black scoters. Some breeding areas were associated with islands, but the role of islands for breeding areas is equivocal. These results aid in the identification of potentially critical breeding areas and provide a baseline classification of breeding habitats used by these two species.

  18. SurfKin: an ab initio kinetic code for modeling surface reactions.

    Science.gov (United States)

    Le, Thong Nguyen-Minh; Liu, Bin; Huynh, Lam K

    2014-10-05

    In this article, we describe a C/C++ program called SurfKin (Surface Kinetics) to construct microkinetic mechanisms for modeling gas-surface reactions. Thermodynamic properties of reaction species are estimated based on density functional theory calculations and statistical mechanics. Rate constants for elementary steps (including adsorption, desorption, and chemical reactions on surfaces) are calculated using the classical collision theory and transition state theory. Methane decomposition and water-gas shift reaction on Ni(111) surface were chosen as test cases to validate the code implementations. The good agreement with literature data suggests this is a powerful tool to facilitate the analysis of complex reactions on surfaces, and thus it helps to effectively construct detailed microkinetic mechanisms for such surface reactions. SurfKin also opens a possibility for designing nanoscale model catalysts. Copyright © 2014 Wiley Periodicals, Inc.

  19. Experimental and numerical investigation of the internal kinetics of a surf-zone plunging breaker

    DEFF Research Database (Denmark)

    Emarat, Narumon; Forehand, David I.M.; Christensen, Erik Damgaard

    2012-01-01

    Over the last couple of decades both the qualitative and quantitative understanding of breaking waves in the surf zone have greatly increased. This is due to the advances in experimental and numerical techniques. However, few comparisons between these two different investigative techniques...... for surfzone breaking waves have been reported. In this study, a comparison is made between the experimental and numerical investigation of the internal kinematics of a surf-zone plunging breaker. The full-field velocity measuring technique known as Particle Image Velocimetry (PIV) is used in the experiments...... was found for all comparisons: free-surface elevations, velocity vector maps, velocity profiles and velocity-magnitude contours. However, some small discrepancies were observed. In the free-surface elevation comparisons, a slight time lag was observed in the numerical results and it is suggested...

  20. A change detection method for remote sensing image based on LBP and SURF feature

    Science.gov (United States)

    Hu, Lei; Yang, Hao; Li, Jin; Zhang, Yun

    2018-04-01

    Finding the change in multi-temporal remote sensing image is important in many the image application. Because of the infection of climate and illumination, the texture of the ground object is more stable relative to the gray in high-resolution remote sensing image. And the texture features of Local Binary Patterns (LBP) and Speeded Up Robust Features (SURF) are outstanding in extracting speed and illumination invariance. A method of change detection for matched remote sensing image pair is present, which compares the similarity by LBP and SURF to detect the change and unchanged of the block after blocking the image. And region growing is adopted to process the block edge zone. The experiment results show that the method can endure some illumination change and slight texture change of the ground object.

  1. Sobre as ondas: surfe, juventude e cultura no Rio de Janeiro dos anos 1960

    Directory of Open Access Journals (Sweden)

    Cleber Dias

    2012-06-01

    Full Text Available Na segunda metade do século XX, torna-se explícita a influência mundial dos Estados Unidos no âmbito esportivo. A disseminação de práticas que possuíam marcas culturais norte-americanas, como é o caso do surfe, não deve ser considerada, contudo, somente como resultado de uma imposição unilateral: há múltiplas apropriações locais que dizem muito sobre o contexto do receptor. Partindo dessa consideração, este artigo objetiva discutir a apreensão do surfe no Rio de Janeiro dos anos 1960. Buscamos debater como a modalidade foi operada como marcador de identidades a partir de vinculações a certas noções de juventude e estilo de vida.

  2. The positive impact of structured surfing courses on the wellbeing of vulnerable young people.

    Science.gov (United States)

    Godfrey, Cath; Devine-Wright, Hannah; Taylor, Joe

    2015-01-01

    Involvement in positive leisure activities is a key way for young people to develop resilience and social and emotional skills. This paper outlines the evaluation of a six-week surfing intervention, the Wave Project, which aimed to boost wellbeing and confidence among 84 young people aged eight to 18, all of whom faced mental health issues or social exclusion. The intervention resulted in a significant and sustained increase in wellbeing. One year later, 70% of clients regularly attend a surf club and many have become trained as session volunteers. Parents and referrers noticed an increase in positive attitude and better communication, as well as improved self-management and behaviour at both home and school It is concluded that the Wave Project provides a demonstrable and cost-effective way to deliver mental health care, mentoring and social integration of young people. Further service evaluation of accessibility and long-term outcomes is also recommended.

  3. InterProSurf: a web server for predicting interacting sites on protein surfaces

    Science.gov (United States)

    Negi, Surendra S.; Schein, Catherine H.; Oezguen, Numan; Power, Trevor D.; Braun, Werner

    2009-01-01

    Summary A new web server, InterProSurf, predicts interacting amino acid residues in proteins that are most likely to interact with other proteins, given the 3D structures of subunits of a protein complex. The prediction method is based on solvent accessible surface area of residues in the isolated subunits, a propensity scale for interface residues and a clustering algorithm to identify surface regions with residues of high interface propensities. Here we illustrate the application of InterProSurf to determine which areas of Bacillus anthracis toxins and measles virus hemagglutinin protein interact with their respective cell surface receptors. The computationally predicted regions overlap with those regions previously identified as interface regions by sequence analysis and mutagenesis experiments. PMID:17933856

  4. Model comparisons of the reactive burn model SURF in three ASC codes

    Energy Technology Data Exchange (ETDEWEB)

    Whitley, Von Howard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stalsberg, Krista Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reichelt, Benjamin Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Shipley, Sarah Jayne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-12

    A study of the SURF reactive burn model was performed in FLAG, PAGOSA and XRAGE. In this study, three different shock-to-detonation transition experiments were modeled in each code. All three codes produced similar model results for all the experiments modeled and at all resolutions. Buildup-to-detonation time, particle velocities and resolution dependence of the models was notably similar between the codes. Given the current PBX 9502 equations of state and SURF calibrations, each code is equally capable of predicting the correct detonation time and distance when impacted by a 1D impactor at pressures ranging from 10-16 GPa, as long as the resolution of the mesh is not too coarse.

  5. Discriminative region extraction and feature selection based on the combination of SURF and saliency

    Science.gov (United States)

    Deng, Li; Wang, Chunhong; Rao, Changhui

    2011-08-01

    The objective of this paper is to provide a possible optimization on salient region algorithm, which is extensively used in recognizing and learning object categories. Salient region algorithm owns the superiority of intra-class tolerance, global score of features and automatically prominent scale selection under certain range. However, the major limitation behaves on performance, and that is what we attempt to improve. By reducing the number of pixels involved in saliency calculation, it can be accelerated. We use interest points detected by fast-Hessian, the detector of SURF, as the candidate feature for saliency operation, rather than the whole set in image. This implementation is thereby called Saliency based Optimization over SURF (SOSU for short). Experiment shows that bringing in of such a fast detector significantly speeds up the algorithm. Meanwhile, Robustness of intra-class diversity ensures object recognition accuracy.

  6. The Design and Implementation of a Prototype Surf-Zone Robot for Waterborne Operations

    Science.gov (United States)

    2015-12-01

    Measurement Unit IR Infrared MC Mission Complexity MONTe Mobility over Non-Trivial Terrain MOSART Mobile Surf-zone Amphibious Robot NIST... rubber coating (Plasti-Dip) and a liquid repellent treatment (Rust-Oleum Never Wet–multisurface). An FDM sparse part T5 was coated as depicted in Figure...Coating Process on FDM Part T5 Figure 15. (a) FDM part with two layers of black rubber coating (first coating), (b) FDM part with liquid repelling

  7. "Sub-Surf Rocks"! An A-Level Resource Developed through an Industry-Education Collaboration

    Science.gov (United States)

    Mather, Hazel

    2012-01-01

    A free internet resource called "Sub-Surf Rocks"! was launched in 2010. Its aim is to use seismic data obtained by the oil industry for enhancing the teaching of structural and economic geology at A-level (ages 16-18) in the UK. Seismic data gives a unique insight into the sub-surface and the many high-quality images coupled with…

  8. Tissue- and species-specific differences in cytochrome c oxidase assembly induced by SURF1 defects

    Czech Academy of Sciences Publication Activity Database

    Kovářová, Nikola; Pecina, Petr; Nůsková, Hana; Vrbacký, Marek; Zeviani, M.; Mráček, Tomáš; Viscomi, C.; Houštěk, Josef

    2016-01-01

    Roč. 1862, č. 4 (2016), s. 705-715 ISSN 0925-4439 R&D Projects: GA ČR(CZ) GB14-36804G; GA MŠk(CZ) LL1204; GA MZd(CZ) NT12370 Institutional support: RVO:67985823 Keywords : cytochrome c oxidase * respiratory supercomplexes * leigh syndrome * SURF1−/− mouse knockout * doxycycline * pulse-chase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.476, year: 2016

  9. Baseline Measurements of Shoulder Surfing Analysis and Comparability for Smartphone Unlock Authentication

    Science.gov (United States)

    2017-05-22

    In this research, we explore a novel approach to measuring the susceptibility of smarthphone unlock authentication to shoulder surfing attacks. We...have created a series of video recordings where researchers enter authentication sequences into mobile devices (e.g. PINs, graphical patterns with...and played the role of attackers, viewing video-recorded footage of PIN and graphical pattern authentication input with various camera angles, hand

  10. Adaptation of respiratory chain biogenesis to cytochrome c oxidase deficiency caused by SURF1 gene mutations

    Czech Academy of Sciences Publication Activity Database

    Kovářová, Nikola; Vrbacká-Čížková, Alena; Pecina, Petr; Stránecký, V.; Pronicka, E.; Kmoch, S.; Houštěk, Josef

    2012-01-01

    Roč. 1822, č. 7 (2012), s. 1114-1124 ISSN 0925-4439 R&D Projects: GA MZd(CZ) NS9759; GA MZd(CZ) NT12370; GA ČR(CZ) GD305/08/H037 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : mitochondrial disorder * SURF1 gene * Leigh syndrome * gene expression * oxidative phosphorylation * cytochrome c oxidase Subject RIV: FG - Pediatrics Impact factor: 4.910, year: 2012

  11. Current research at NBS using synchrotron radiation at SURF-II

    International Nuclear Information System (INIS)

    Parr, A.C.; Rakowsky, G.; Ederer, D.L.; Stockbauer, R.L.; West, J.B.; Dehmer, J.L.

    1980-01-01

    The National Bureau of Standards (NBS) Synchrotron Ultraviolet Radiation Facility (SURF-II) is used in conjunction with a high flux normal incidence monochromator for angle resolved wavelength dependent photoelectron studies. The recent work has concentrated on studies of the effect of shape resonances on molecular vibrational intensity distributions as well as the effects of autoionization upon the vibrational intensity distributions over narrow wavelength regions. Results for CO, N 2 , Ar and Xe will be discussed

  12. Surfing and drift acceleration at high mach number quasi-perpendicular shocks

    International Nuclear Information System (INIS)

    Amano, T.

    2008-01-01

    Electron acceleration in high Mach number collisionless shocks relevant to supernova remnant is discussed. By performing one- and two-dimensional particle-in-cell simulations of quasi-perpendicular shocks, we find that energetic electrons are quickly generated in the shock transition region through shock surfing and drift acceleration. The electron energization is strong enough to account for the observed injection at supernova remnant shocks. (author)

  13. Sound Surfing Network (SSN): Mobile Phone-based Sound Spatialization with Audience Collaboration

    OpenAIRE

    Park, Saebyul; Ban, Seonghoon; Hong, Dae Ryong; Yeo, Woon Seung

    2013-01-01

    SSN (Sound Surfing Network) is a performance system that provides a new musicalexperience by incorporating mobile phone-based spatial sound control tocollaborative music performance. SSN enables both the performer and theaudience to manipulate the spatial distribution of sound using the smartphonesof the audience as distributed speaker system. Proposing a new perspective tothe social aspect music appreciation, SSN will provide a new possibility tomobile music performances in the context of in...

  14. Spent unreprocessed fuel (SURF) facility evaluation plan of the alternative storage concepts

    International Nuclear Information System (INIS)

    Berry, S.M.

    1978-01-01

    Concepts were evaluated for the storage of unreprocessed spent fuel in a retrievable surface storage facility. This document provides a systematic format for making a concept selection from the seven alternative concepts presented in RHO-LD-2. Results of the evaluation was that the Drywell concept was rated highest with the Water Basin Concept and the Sealed Storage Cask concept with multiple canisters of SURF coming in a close second and third

  15. CAMSHIFT IMPROVEMENT WITH MEAN-SHIFT SEGMENTATION, REGION GROWING, AND SURF METHOD

    Directory of Open Access Journals (Sweden)

    Ferdinan Ferdinan

    2013-10-01

    Full Text Available CAMSHIFT algorithm has been widely used in object tracking. CAMSHIFT utilizescolor features as the model object. Thus, original CAMSHIFT may fail when the object color issimilar with the background color. In this study, we propose CAMSHIFT tracker combined withmean-shift segmentation, region growing, and SURF in order to improve the tracking accuracy.The mean-shift segmentation and region growing are applied in object localization phase to extractthe important parts of the object. Hue-distance, saturation, and value are used to calculate theBhattacharyya distance to judge whether the tracked object is lost. Once the object is judged lost,SURF is used to find the lost object, and CAMSHIFT can retrack the object. The Object trackingsystem is built with OpenCV. Some measurements of accuracy have done using frame-basedmetrics. We use datasets BoBoT (Bonn Benchmark on Tracking to measure accuracy of thesystem. The results demonstrate that CAMSHIFT combined with mean-shift segmentation, regiongrowing, and SURF method has higher accuracy than the previous methods.

  16. Does human pressure affect the community structure of surf zone fish in sandy beaches?

    Science.gov (United States)

    Costa, Leonardo Lopes; Landmann, Júlia G.; Gaelzer, Luiz R.; Zalmon, Ilana R.

    2017-01-01

    Intense tourism and human activities have resulted in habitat destruction in sandy beach ecosystems with negative impacts on the associated communities. To investigate whether urbanized beaches affect surf zone fish communities, fish and their benthic macrofaunal prey were collected during periods of low and high human pressure at two beaches on the Southeastern Brazilian coast. A BACI experimental design (Before-After-Control-Impact) was adapted for comparisons of tourism impact on fish community composition and structure in urbanized, intermediate and non-urbanized sectors of each beach. At the end of the summer season, we observed a significant reduction in fish richness, abundance, and diversity in the high tourist pressure areas. The negative association between visitors' abundance and the macrofaunal density suggests that urbanized beaches are avoided by surf zone fish due to higher human pressure and the reduction of food availability. Our results indicate that surf zone fish should be included in environmental impact studies in sandy beaches, including commercial species, e.g., the bluefish Pomatomus saltatrix. The comparative results from the less urbanized areas suggest that environmental zoning and visitation limits should be used as effective management and preservation strategies on beaches with high conservation potential.

  17. Mechanical interactions in bacterial colonies and the surfing probability of beneficial mutations.

    Science.gov (United States)

    Farrell, Fred D; Gralka, Matti; Hallatschek, Oskar; Waclaw, Bartlomiej

    2017-06-01

    Bacterial conglomerates such as biofilms and microcolonies are ubiquitous in nature and play an important role in industry and medicine. In contrast to well-mixed cultures routinely used in microbial research, bacteria in a microcolony interact mechanically with one another and with the substrate to which they are attached. Here, we use a computer model of a microbial colony of rod-shaped cells to investigate how physical interactions between cells determine their motion in the colony and how this affects biological evolution. We show that the probability that a faster-growing mutant 'surfs' at the colony's frontier and creates a macroscopic sector depends on physical properties of cells (shape, elasticity and friction). Although all these factors contribute to the surfing probability in seemingly different ways, their effects can be summarized by two summary statistics that characterize the front roughness and cell alignment. Our predictions are confirmed by experiments in which we measure the surfing probability for colonies of different front roughness. Our results show that physical interactions between bacterial cells play an important role in biological evolution of new traits, and suggest that these interactions may be relevant to processes such as de novo evolution of antibiotic resistance. © 2017 The Author(s).

  18. Zonation of macrofauna across sandy beaches and surf zones along the Dutch coast

    Directory of Open Access Journals (Sweden)

    Gerard Janssen

    2005-06-01

    Full Text Available On nine beaches and two transects in the surf zone along the Dutch coast the presence of benthic macrofauna was studied in relation to basic abiotic characteristics. According to Short's classification system, Dutch beaches are mesotidal and dissipative (Ω = 8.6, and the RTR is low (1.52-1.27, which means that they are not tide-dominated. BSI ranged from 1.4 to 1.1 for the northern and western Dutch coasts respectively and had an overall value of 1.2. The rates of exposure of the beaches varied between 8 and 12, and are therefore regarded as sheltered to moderately exposed. The Dutch beaches display a geographical trend in beach types. Those of the Wadden Sea islands in the northern part of the Netherlands are dissipative, flat, fine-grained, and host high densities of many species of benthic macrofauna. The beaches along the western Dutch coast are less dissipative, steeper, with a higher mean grain size; the species diversity and abundance there are lower. Species diversity and abundance on the beaches increase from the high- to the low-water line. The maximum number of species was found between 0 and -1 m relative to the mean tidal level. The abundance peaks just above the mean tidal level, while the biomass reaches a maximum at the mean tidal level.     Species diversity and abundance are low in the surf zone, but increase towards deeper water. Species numbers are high and the abundance is very high in the trough between the two bars.     The relation between the diversity and abundance of macrobenthic species on the one hand, and the sediment composition, water column depth, and position between the bars on the other show a clear pattern of zonation for the beach, surf zone and near-shore: (1 a supralittoral zone with insects and air-breathing crustaceans, (2 a midshore zone, with intertidal species, (3 a lower shore zone, whose species extend into the shallow surf zone, and (4 a zone of sublittoral fauna in the trough between the

  19. Pollution level and inhalation exposure of ambient aerosol fluoride as affected by polymetallic rare earth mining and smelting in Baotou, north China

    Science.gov (United States)

    Zhong, Buqing; Wang, Lingqing; Liang, Tao; Xing, Baoshan

    2017-10-01

    Airborne fluoride associated with total suspended particles (TSP) and respirable particulate (PM10) in the rare earth mining and smelting areas were analyzed during August 2012 and March 2013. In March, average concentrations of fluoride bound to TSP in the mining and smelting areas were 0.598 ± 0.626 μg/m3 and 3.615 ± 4.267 μg/m3, respectively, whereas that in August were 0.699 ± 0.801 μg/m3 and 1.917 ± 2.233 μg/m3, respectively. TSP samples were classified into four categories by different sampling periods and locations using Kohonen's self-organizing map, which demonstrates that high airborne fluoride concentrations in March in the smelting area were probably attributed to industrial emissions from smelting activities and wind-blown dust from tailings pond, influenced by meteorologic parameters such as temperature, relative humidity, precipitation and wind speed. The mean daily amount of fluoride inhaled in the mining and smelting areas were estimated to be in the range of 2.77-57.61 μg/day and 3.39-64.32 μg/day, respectively. These results indicate the high potential exposure level of fluoride inhaled for local residents in the polymetallic mining and smelting areas.

  20. EAF smelting trials of waste-carbon briquettes at Avesta Works of Outokumpu Stainless AB for recycling oily mill scale sludge from stainless steel production

    Energy Technology Data Exchange (ETDEWEB)

    Yang Qixing; Bjoerkman, Bo [Div. of Process Metallurgy, Lulea Univ. of Tech., Lulea (Sweden); Holmberg, Nils [Raw Materials Handling, Avesta Works, Outokumpu Stainless AB, Avesta (Sweden)

    2009-06-15

    The EAF steel plant of Avesta Works, Outokumpu Stainless AB, has been used to perform smelting reduction trials of briquettes consisting of oily mill scale sludge, carbon and other wastes. A total of 7 briquette smelting trials were performed. The heats were processed smoothly smelting 3 t of briquettes or 3.4 mass-% of metal charges. The quantities of FeSi powder and O{sub 2} gas injected and electric energy supplied were increased to smelt briquettes of 6 t. No impacts were found on the analyses of the crude stainless steel tapped from the EAF during the trials. The results of the briquette smelting have been evaluated by referring to the data from the reference heats and results from earlier laboratory tests. The recovery of Cr, Ni and Fe elements from the briquettes was nearly complete and was found to occur mainly through carbon reduction. The slag masses were not increased in three trials as compared with the reference heats. There were moderate increases in the slag masses in four trial heats. The increases were, nevertheless, lower by 52-69% than the slag masses generated by Si-reduction of the briquette oxides. Afterwards, by referring results from the present trials, waste-carbon briquettes amounting to 1-3 t were smelted very smoothly in many of the EAF heats at Avesta Works to recycle the oily mill scale sludge and other wastes from stainless steel production. (orig.)

  1. Toxic metal levels in children residing in a smelting craft village in Vietnam: a pilot biomonitoring study.

    Science.gov (United States)

    Sanders, Alison P; Miller, Sloane K; Nguyen, Viet; Kotch, Jonathan B; Fry, Rebecca C

    2014-02-04

    In Vietnam, environmental pollution caused by small-scale domestic smelting of automobile batteries into lead ingot is a growing concern. The village of Nghia Lo is a smelting craft village located roughly 25 km southeast of Hanoi in the Red River Delta. Despite the concern of toxic metal exposure in the village, biomonitoring among susceptible populations, such as children, has not been previously conducted. The aim of this study was to determine the body burden of toxic metals in children residing in a smelting craft village. Twenty children from Nghia Lo, Vietnam, ages 18 months to four years were selected for capillary whole blood and toenail biomonitoring. Whole blood lead levels (BLLs) were measured using a portable lead analyzer, and toenail levels of arsenic, cadmium, chromium, lead, manganese, and mercury were analyzed with inductively coupled plasma-mass spectrometry. The findings show that all of the 20 children had detectable BLLs, and every child had levels that exceeded the Centers for Disease Control and Prevention guideline level of 5 μg/dL. Eighty percent of tested subjects had BLLs higher than 10 μg/dL. Five children (25%) had BLLs greater than 45 μg/dL, the level of recommended medical intervention. In addition to blood lead, all of the children had detectable levels of arsenic, cadmium, chromium, lead, manganese, and mercury in toenail samples. Notably, average toenail lead, manganese, and mercury levels were 157 μg/g, 7.41 μg/g, and 2.63 μg/g respectively, well above levels previously reported in children. Significant Spearman's rank correlations showed that there were relationships between blood and toenail lead levels (r = 0.65, p craft villages in Vietnam are co-exposed to toxic metals. There is an urgent need for mitigation to control metal exposure related to domestic smelting.

  2. Patterns of recruitment of the sand smelt (Atherina presbyter on rocky intertidal habitats

    Directory of Open Access Journals (Sweden)

    Frederico Almada

    2015-11-01

    Full Text Available The Portuguese coast is located in a biogeographical transition zone between temperate and subtropical waters making it especially vulnerable to the effects of climate change. Several fish species struggle to cope with these annual changing conditions, particularly species that strongly depend on intertidal habitats which are expected to endure higher ecological fluctuations. Sand smelt young recruits and larvae were collected at the west coast of Portugal in the intertidal by hand-netting, and in the subtidal with light traps and scuba diving with plankton nets attached to scooters (Parede/Avencas: 38º 41’ N, 9º 21’W and Arrábida: 38º 28’ N, 8º 59’W, respectively. Due to the morphological similarities with other congeneric species young specimens were regularly collected and identified through genetic analysis. All samples were assigned to the same species: A. presbyter. Results showed that A. presbyter is one of the most abundant non-resident fish species in these rocky coastal areas, representing 49% (n=93.958 of the total number of individuals sighted in the intertidal from 2009-2015, but only 0.55% of the total number of individuals sampled in the subtidal (n=176 with both methods from 2011-2013. Distribution patterns showed that recruits (TL 0.8-6.8 cm concentrated within the intertidal area between March and December. Younger cohorts (TL 0.8-1.2 cm are captured almost exclusively in these areas including confined intertidal channels and large pools between March and August, suggesting that reproduction and spawning can occur for a period of 6 months. Inter-annual seasonal variations from 2009 to 2015 showed irregular water temperature profiles, especially in 2011 and 2012, which may dramatically affect the reproductive success of this species, not only reducing the number of recruits but also shortening the recruitment period from 10 to 5 months. Globally, 46% of the coastlines have experienced a significant decrease in the

  3. Effect of smelting method on the austenite grain size and properties of heat-resisting pearlitic steel

    International Nuclear Information System (INIS)

    Balakhovskaya, M.B.; Khusainova, N.A.; Davlyatova, L.N.

    1975-01-01

    Influence of smelting method on austenite grain size and properties of refractory perlite steel were studied. An opportunity was found to increase the steel refractoriness without deteriorating its other properties. The steel 12Kh1MF of electric or common open-hearth smelting was used. The dependence of kinetics of austenite grain growth on the smelting method was studied in the temperature range 950 deg - 1200 deg C with 1 hour exposure. The grain size of austenite in steel is supposedly determined by aluminium nitrides and vanadium carbides. In tests of normalized (kept for 20 minutes at 950-980 deg C) and tempered (kept for 3 hours at 730 deg C) transverse (tangential) pipe cross-section samples the electric steel had higher impact viscosity than the open-hearth metal. At working temperatures (540 deg -580 deg C) the difference in viscosity has its minimum. Viscosity of both steels 12Kh1MF begins to sharply decrease from 20 deg C. However, electric steel has rather high viscosity even at - 40 deg C, while the open-hearth one becomes brittle as early as at - 20 deg C. Long-term strength tests at 580 deg C under stresses 10-14 kG/mm 2 show that the coarse-grain steel is more refractory, i.e. time till fracture of open-hearth steel samples is twice as long as that of electric steel samples

  4. Effect of smelting method on the austenite grain size and properties of heat-resisting pearlitic steel

    Energy Technology Data Exchange (ETDEWEB)

    Balakhovskaya, M B; Khusainova, N A; Davlyatova, L N [Vsesoyuznyj Nauchno-Issledovatel' skij Teplotekhnicheskij Inst., Moscow (USSR)

    1975-12-01

    Influence of smelting method on austenite grain size and properties of refractory perlite steel were studied. An opportunity was found to increase the steel refractoriness without deteriorating its other properties. The steel 12Kh1MF of electric or common open-hearth smelting was used. The dependence of kinetics of austenite grain growth on the smelting method was studied in the temperature range 950 deg - 1200 deg C with 1 hour exposure. The grain size of austenite in steel is supposedly determined by aluminium nitrides and vanadium carbides. In tests of normalized (kept for 20 minutes at 950-980 deg C) and tempered (kept for 3 hours at 730 deg C) transverse (tangential) pipe cross-section samples the electric steel had higher impact viscosity than the open-hearth metal. At working temperatures (540 deg -580 deg C) the difference in viscosity has its minimum. Viscosity of both steels 12Kh1MF begins to sharply decrease from 20 deg C. However, electric steel has rather high viscosity even at /sup -/40 deg C, while the open-hearth one becomes brittle as early as at /sup -/20 deg C. Long-term strength tests at 580 deg C under stresses 10-14 kG/mm/sup 2/ show that the coarse-grain steel is more refractory, i.e. time till fracture of open-hearth steel samples is twice as long as that of electric steel samples.

  5. Atmospheric thorium pollution and inhalation exposure in the largest rare earth mining and smelting area in China.

    Science.gov (United States)

    Wang, Lingqing; Zhong, Buqing; Liang, Tao; Xing, Baoshan; Zhu, Yifang

    2016-12-01

    Exposure to radionuclide thorium (Th) has generated widespread public concerns, mainly because of its radiological effects on human health. Activity levels of airborne 232 Th in total suspended particulate (TSP) were measured in the vicinity of the largest rare earth mine in China in August 2012 and March 2013. The mean activity concentrations of 232 Th in TSP ranged from 820μBqm -3 in a mining area in August 2012 to 39,720μBqm -3 in a smelting area in March 2013, much higher than the world reference of 0.5μBqm -3 . Multistatistical analysis and Kohonen's self-organizing maps suggested that 232 Th in TSP was mainly derived from rare earth mining and smelting practices. In addition, personal inhalation exposures to 232 Th associated with respirable particulate (PM 10 ) were also measured among local dwellers via personal monitoring. The mean dose values for different age groups in the smelting and mining areas ranged from 97.86 to 417μSvyear - 1 and from 101.03 to 430.83μSvyear -1 , respectively. These results indicate that people living in the study areas are exposed to high levels of widespread 232 Th. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Industrial activity, gas emissions and environmental urban management. Operative condition's diagnostic of smelting activities in Tandil, Argentina

    International Nuclear Information System (INIS)

    Soledad Sosa, Beatriz; Guerrero, Elsa Marcela; Banda Noriega, Roxana

    2013-01-01

    Amongst urban environmental problems, those associated to industry are of particular interest in environmental management. Tandil, a city in Argentina, owes its economic and urban growth to metalworking activity, especially to smelting. Despite the crisis in the sector, activity continues to be the axis of local economic and urban growth. The present research characterizes, in production, operative and environmental terms, local smelting industries and assesses operative conditions of gas emissions management during 2010. There were analyzed 25 industries over 30. The sample was representative of five productive processes: aluminum (Al), aluminum/iron (Al Fe), aluminum/bronze (Al Cu+Sn), aluminum/iron/bronze (Al Fe Cu+Sn), and iron (Fe). The variables analyzed were: primary fusion mater, oven used and industry size. To obtain production data we applied structured interviews, and for industry sizes we used surveys. It was possible to describe the productive prospect of the sector at a local level: for most industries the destination of their production is automotive sector. Taking into account the relation between the size and the type of industry, the aluminum smelting companies are small. Regarding iron industries, all three company sizes are present in the sample and exists a medium size industry that occupies between 51 and 230 employees. The operative conditions and their compliance with current legislation regarding control of gas emissions require to identify monitoring indicators for the melting stage that allow knowing precisely the resulting contaminants and their environmental effects.

  7. Sodium Silicate Gel Effect on Cemented Tailing Backfill That Contains Lead-Zinc Smelting Slag at Early Ages

    Directory of Open Access Journals (Sweden)

    Lijie Guo

    2018-01-01

    Full Text Available This paper presents the results of an experimental study on the priming effect of sodium silicate gel (SS on cemented tailing backfill (CTB that contains lead-zinc smelting slag. CTB and cemented paste (CP containing lead-zinc smelting slag samples with SS of 0 and 0.4% of the mass of the slag were prepared and cured at 20°C for 1, 3, 7, and 28 days. Mechanical test and pore structure analyses were performed on the studied CTB samples, microstructural analyses (X-ray diffraction analysis and thermal gravity analysis were performed on the studied CP samples, whereas the electrical conductivity of CTB was monitored. The results reveal that SS has a significant positive effect on cementitious activity of binder mixed by cement and lead-zinc smelting slag. This activation leads to the acceleration of binder hydration process, the formation of more cement hydration products in the CTBs, and the refinement of their pore structure, which is favorable for the strength development of CTB.

  8. Ichthyoplankton in a southern african surf zone: Nursery area for the postlarvae of estuarine associated fish species?

    Science.gov (United States)

    Whitfield, A. K.

    1989-12-01

    The surf zone ichthyoplankton of Swartvlei Bay was studied between February 1986 and June 1987, with particular emphasis on its potential role as a nursery area for estuarine associated marine fish species. Larvae and/or postlarvae of 16 families were identified from the surf zone, with the Gobiidae, Soleidae, Sparidae and Mugilidae comprising 85·7% of all teleosts sampled. The postlarvae of several taxa (including the six most common species), which utilize the Swartvlei estuary as a juvenile nursery area, were abundant in the surf zone. Conversely, species which are common in nearshore marine waters as juveniles and adults, but seldom enter estuaries, totalled less than 8% of the surf zone ichthyoplankton assemblage. Larval and postlarval densities peaked during summer when water temperatures exceeded 19°C and the estuary mouth was open. Concentrations of ichthyoplankton were highest at those sampling stations closest to the estuary mouth during the summer period. Diel changes in total catches revealed no significant difference between day and night densities; but of the four major taxa, the Mugilidae and Sparidae tended to be more abundant during the day, the Gobiidae at night and the Soleidae showed no distinct pattern. Results from a 24 h sampling session indicated that tidal phase may also be important in governing ichthyoplankton abundance in the surf zone.

  9. Study on Apparent Kinetic Prediction Model of the Smelting Reduction Based on the Time-Series

    Directory of Open Access Journals (Sweden)

    Guo-feng Fan

    2012-01-01

    Full Text Available A series of direct smelting reduction experiment has been carried out with high phosphorous iron ore of the different bases by thermogravimetric analyzer. The derivative thermogravimetric (DTG data have been obtained from the experiments. One-step forward local weighted linear (LWL method , one of the most suitable ways of predicting chaotic time-series methods which focus on the errors, is used to predict DTG. In the meanwhile, empirical mode decomposition-autoregressive (EMD-AR, a data mining technique in signal processing, is also used to predict DTG. The results show that (1 EMD-AR(4 is the most appropriate and its error is smaller than the former; (2 root mean square error (RMSE has decreased about two-thirds; (3 standardized root mean square error (NMSE has decreased in an order of magnitude. Finally in this paper, EMD-AR method has been improved by golden section weighting; its error would be smaller than before. Therefore, the improved EMD-AR model is a promising alternative for apparent reaction rate (DTG. The analytical results have been an important reference in the field of industrial control.

  10. Antimony smelting process generating solid wastes and dust: characterization and leaching behaviors.

    Science.gov (United States)

    Guo, Xuejun; Wang, Kunpeng; He, Mengchang; Liu, Ziwei; Yang, Hailin; Li, Sisi

    2014-07-01

    A large amount of solid waste has been produced by the antimony smelting process in the "World Capital of Antimony", Xikuangshan area in China. This study comprehensively investigated the physical and chemical characteristics of the various solid wastes, as well as the leaching behavior of the solid wastes, which included water-quenched slag, arsenic-alkali residue, desulfurized slag and blast furnace dust. These four types of waste were enriched in a variety of heavy metals and metalloids and more specifically with As and Sb levels up to 8.6 × 10⁴ and 3.16×10⁵ mg/kg, respectively, in arsenic-alkali residue. For desulfurized slag and water-quenched slag, the leaching concentration of Sb significantly exceeded the acceptable limits during the leaching tests using the toxicity characteristic leaching procedure and the synthetic precipitation leaching procedure. In addition, As leaching in arsenic-alkali residue was extraordinarily hazardous, being three orders of magnitude higher than the regulatory level of As. According to the results of the extraction tests, all the tested wastes were classified as hazardous waste. Copyright © 2014. Published by Elsevier B.V.

  11. Questions about the reliability of recovery boilers of steel smelting units

    Energy Technology Data Exchange (ETDEWEB)

    Sazykin, Yu K; Mukhametzyanov, N K

    1979-01-01

    Because the main reason for failure of recovery boilers is contamination of the heating surfaces, the operational conditions of individual elements of boiler units, equipped with vibrational and pulsed cleaning are analyzed and the reliability of the cleaning systems in use today is evaluated. The recovery boilers from open hearth furnaces and two bath steel smelting units from the Magnitogorsk Metallurgic Combine were selected as the subjects of the study. It is established that the boiler heating surface cleaning system has a quite large number of failures. The vibrational cleaning readiness factor is rated at 0.9323 and that of the pulsed cleaning system, 0.9698. For the KU-100 recovery boilers with a mean productivity of 18-20 t/h, the losses caused by failures during operation with vibration and pulsed cleaning were 3,200 and 1,700 rubles per year, respectively. With reconstruction of the boilers, which is associated with an increase in their reliability, the vibration cleaning of the heating surface was replaced by pulsed cleaning.

  12. Nonlinear system identification of the reduction nickel oxide smelting process in electric arc furnace

    Science.gov (United States)

    Gubin, V.; Firsov, A.

    2018-03-01

    As the title implies the article describes the nonlinear system identification of the reduction smelting process of nickel oxide in electric arc furnaces. It is suggested that for operational control ratio of components of the charge must be solved the problem of determining the qualitative composition of the melt in real time. The use of 0th harmonic of phase voltage AC furnace as an indirect measure of the melt composition is proposed. Brief description of the mechanism of occurrence and nature of the non-zero 0th harmonic of the AC voltage of the arc is given. It is shown that value of 0th harmonic of the arc voltage is not function of electrical parameters but depends of the material composition of the melt. Processed industrial data are given. Hammerstein-Wiener model is used for description of the dependence of 0th harmonic of the furnace voltage from the technical parameters of melting furnace: the melt composition and current. Recommendations are given about the practical use of the model.

  13. Arsenic exposure levels in relation to different working departments in a copper mining and smelting plant

    Science.gov (United States)

    Sun, Qingshan; Song, Yingli; Liu, Shengnan; Wang, Fei; Zhang, Lin; Xi, Shuhua; Sun, Guifan

    2015-10-01

    The investigation was carried out to evaluate arsenic exposure and the urine metabolite profiles of workers with different working departments, including administration (Group1), copper ore mining (Group2), copper ore grinding (Group3), electrolytic procession (Group4) and copper smelting (Group5) in a Copper mining and processing plant in China. Information about characteristics of each subject was obtained by questionnaire and inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) in urine were determined. The highest urinary levels of iAs, MMA and DMA all were found in the Group 5. Group 4 workers had a higher iAs% and a lower PMI compared to Group 3. The urinary total As (TAs) levels of 54.7% subjects exceeded 50 μg/g Cr, and the highest percentage (93.3%) was found in Group 5, smelters. The results of the present study indicate that workers in copper production plant indeed exposed to As, especially for smelters and workers of electrolytic process.

  14. Influence of alumina on mineralogy and environmental properties of zinc-copper smelting slags

    Science.gov (United States)

    Mostaghel, Sina; Samuelsson, Caisa; Björkman, Bo

    2013-03-01

    An iron-silicate slag, from a zinc-copper smelting process, and mixtures of this slag with 5wt%, 10wt%, and 15wt% alumina addition were re-melted, semi-rapidly solidified, and characterized using scanning electron microscopy equipped with energy dispersive spectroscopy, and X-ray diffraction. The FactSage™6.2 thermodynamic package was applied to compare the stable phases at equilibrium conditions with experimental characterization. A standard European leaching test was also carried out for all samples to investigate the changes in leaching behaviour because of the addition of alumina. Results show that the commonly reported phases for slags from copper and zinc production processes (olivine, pyroxene, and spinel) are the major constituents of the current samples. A correlation can be seen between mineralogical characteristics and leaching behaviours. The sample with 10wt% alumina addition, which contains high amounts of spinels and lower amounts of the other soluble phases, shows the lowest leachabilities for most of the elements.

  15. Different Heavy Metal Accumulation Strategies of Epilithic Lichens Colonising Artificial Post-Smelting Wastes.

    Science.gov (United States)

    Rola, Kaja; Osyczka, Piotr; Kafel, Alina

    2016-02-01

    Lichens appear to be essential and effective colonisers of bare substrates including the extremely contaminated wastes of slag dumps. This study examines the metal accumulation capacity of epilithic lichens growing directly on the surface of artificial slag sinters. Four species representing different growth forms, i.e., crustose Candelariella aurella, Lecanora muralis, and Lecidea fuscoatra and fruticose Stereocaulon nanodes, were selected to evaluate the relationships between zinc, lead, cadmium, and nickel contents in their thalli and host substrates. Bioaccumulation factors of examined crustose lichens showed their propensity to hyperaccumulate heavy metals. Contrarily, concentrations of metals in fruticose thalli of S. nanodes were, as a rule, lower than in the corresponding substrates. This indicates that the growth form of thalli and degree of thallus adhesion to the substrate has a significant impact on metal concentrations in lichens colonising post-smelting wastes. Nonlinear regression models described by power functions show that at greater levels of Pb concentration in the substrate, the ability of C. aurella, L. muralis and L. fuscoatra to accumulate the metal experiences a relative decrease, whereas hyperbolic function describes a similar trend in relation to Ni content in S. nanodes. This phenomenon may be an important attribute of lichens that facilitates their colonisation of the surface of slag wastes.

  16. Environmental legacy of copper metallurgy and Mongol silver smelting recorded in Yunnan Lake sediments.

    Science.gov (United States)

    Hillman, Aubrey L; Abbott, Mark B; Yu, JunQing; Bain, Daniel J; Chiou-Peng, TzeHuey

    2015-03-17

    Geochemical measurements on well-dated sediment cores from Lake Er (Erhai) are used to determine the timing of changes in metal concentrations over 4500 years in Yunnan, a borderland region in southwestern China noted for rich mineral deposits but with inadequately documented metallurgical history. Our findings add new insight into the impacts and environmental legacy of human exploitation of metal resources in Yunnan history. We observe an increase in copper at 1500 BC resulting from atmospheric emissions associated with metallurgy. These data clarify the chronological issues related to links between the onset of Yunnan metallurgy and the advent of bronze technology in adjacent Southeast Asia, subjects that have been debated for nearly half a century. We also observe an increase from 1100 to 1300 AD in a number of heavy metals including lead, silver, zinc, and cadmium from atmospheric emissions associated with silver smelting. Culminating during the rule of the Mongols, known as the Yuan Dynasty (1271-1368 AD), these metal concentrations approach levels three to four times higher than those from industrialized mining activity occurring within the catchment today. Notably, the concentrations of lead approach levels at which harmful effects may be observed in aquatic organisms. The persistence of this lead pollution over time created an environmental legacy that likely contributes to known issues in modern day sediment quality. We demonstrate that historic metallurgical production in Yunnan can cause substantial impacts on the sediment quality of lake systems, similar to other paleolimnological findings around the globe.

  17. Characterizing surf zone injuries from the five most populated beaches on the Atlantic-fronting Delaware coast: Delaware surf zone injury demographics.

    Science.gov (United States)

    Doelp, Matthew B; Puleo, Jack A; Cowan, Paul; Arford-Granholm, Michelle

    2017-12-24

    Beaches are a popular destination for recreation activities. Surf zone injuries (SZI) can occur resulting from a variety of in-water activities. Little is known regarding the sustained injury types, or demographics of injured persons and activities leading to injuries. This study examines the distribution of SZI types, activities and populations occurring on Delaware Beaches as recorded by a local level III trauma center (Department of Emergency Medicine at Beebe Healthcare in Lewes, Delaware). There were 2021 injuries over the eight study years (2010-2017). The relative demographics of the injured population are similar despite fluctuating injury totals (mean [SD], 253.1 [104.4]). Non-locals (n=1757) were 6.7 times more likely to be injured as their local (n=264) counterparts (RR, 2.62; 95% CI, 2.08-3.31). Males (n=1258) were 1.7 times more likely to be injured than their female (n=763) counterparts (RR, 1.29; 95% CI, 1.21-1.37). Serious injuries, defined as patients requiring admission to a trauma service, represented 9.1% (n=184) of injuries. Fatal SZI (n=6) were categorized as serious injuries. Wading (50.1%) was found to be the dominant activity associated with injury followed by body surfing (18.4%), and body boarding (13.3%). To the authors' knowledge, this study is one of the first to investigate long-term trends in SZI data, injury activity, and demographics. Better understanding of the characteristics of injuries will allow for improved awareness techniques, targeted at populations with higher injury rates. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. The imbalanced surfing-life of humanity to survival in the global changes

    Science.gov (United States)

    Kontar, V. A.

    2013-12-01

    We have written many times about the imbalance of Nature as the cause of the global change. Here, we offer some method for the humanity survival in the face of global change of the imbalanced anisotropic real Nature. There are two logics of understanding the real Nature: the traditional balanced, and the new imbalanced. The balanced logic presupposes that Nature is balanced, isotropic, etc. The imbalanced logic presupposes opposite that Nature is imbalanced, anisotropic, etc. Respectively can be two styles of the people life: balanced and imbalanced. The image of the flat earth corresponds well with the balanced lifestyle of people. On the balanced life people spend activities to achieve the balance by reducing the change, stabilization, leveling any level changes, etc. If there is a mountain on the road, it must be align the track or make the tunnel. If there is a ravine on the road, then it need backfilled or to build a bridge. If someone is in restless, it must be calm, etc. As example of the happiness in the balanced life is the stability, balance, and therefore the global changes of Nature are perceived as a catastrophe. In the balanced lifestyle people can easily decide to use force, especially if there is not enough knowledge. But Nature has power which in billions times greater than the forces of humanity. Therefore, humanity will beaten in struggle with Nature and disappear. The imbalanced lifestyle is the fundamentally different. The imbalanced lifestyle complies with the surface of the ocean, which always changes, but sometimes can be and flat. But the flat calm ocean surface is inconvenient for the imbalanced life. You need to pull boat yourself because is no wind in the sails. The anisotropic imbalanced Nature has gradients in all parameters. At a certain level of knowledge and experience, people can use this multi-dimensional gradient essence of the real Nature for human's discretion. The imbalanced life is like a surfing. If properly understood

  19. Simultaneous Observations of Beach and Surf-Zone Topography from a sUAS

    Science.gov (United States)

    Slocum, R. K.; Brodie, K. L.; Spore, N.

    2016-02-01

    Beaches and surf-zones can vary rapidly in time and space, necessitating frequent, spatially extensive observations for up-to-date knowledge on their current condition. Traditional surveying methods are expensive, can be dangerous in large wave conditions, and can lack sufficient spatial density. Existing remote sensing technologies have focused on both active sensing (airborne lidar, X-band radar) or passive sensing (electro-optical or infrared imagery) to either directly measure elevations of the beach and seafloor or exploit the optical signal of refracting and breaking waves in the surf-zone. These methods, however, can be prohibitively expensive for widespread, high temporal frequency use, or lack the spatial coverage required to quantify a large stretch of beach. UAS offer an affordable and accessible alternative, but existing COTS UAS sensor suites are not optimized for generation of bathymetry and topography at the same time. Here, we present a new approach using an inexpensive, custom multi-camera sensor designed with a wide field of view for integration on either a fixed wing of multirotor UAS platform. We introduce a processing methodology and workflow to generate a topographic pointcloud and rectified imagery of the water surface using structure from motion algorithms. The topographic pointcloud data is processed to generate a DSM of the beach and extract morphologic parameters (beach slope, dune toe, etc). Rectified imagery of the water surface is used to quantify sandbar location as well as perform a celerity based bathymetric inversion. Accuracy of this methodology is calculated by comparing processed data to lidar pointclouds, as well as photo identifiable targets on the beach and jetted into the surf zone. Funded by the USACE Military Engineering POD:A&U Program and Coastal Field Data Collection Program.

  20. Prediction and assimilation of surf-zone processes using a Bayesian network: Part I: Forward models

    Science.gov (United States)

    Plant, Nathaniel G.; Holland, K. Todd

    2011-01-01

    Prediction of coastal processes, including waves, currents, and sediment transport, can be obtained from a variety of detailed geophysical-process models with many simulations showing significant skill. This capability supports a wide range of research and applied efforts that can benefit from accurate numerical predictions. However, the predictions are only as accurate as the data used to drive the models and, given the large temporal and spatial variability of the surf zone, inaccuracies in data are unavoidable such that useful predictions require corresponding estimates of uncertainty. We demonstrate how a Bayesian-network model can be used to provide accurate predictions of wave-height evolution in the surf zone given very sparse and/or inaccurate boundary-condition data. The approach is based on a formal treatment of a data-assimilation problem that takes advantage of significant reduction of the dimensionality of the model system. We demonstrate that predictions of a detailed geophysical model of the wave evolution are reproduced accurately using a Bayesian approach. In this surf-zone application, forward prediction skill was 83%, and uncertainties in the model inputs were accurately transferred to uncertainty in output variables. We also demonstrate that if modeling uncertainties were not conveyed to the Bayesian network (i.e., perfect data or model were assumed), then overly optimistic prediction uncertainties were computed. More consistent predictions and uncertainties were obtained by including model-parameter errors as a source of input uncertainty. Improved predictions (skill of 90%) were achieved because the Bayesian network simultaneously estimated optimal parameters while predicting wave heights.

  1. Performance of the SURF-II high-throughput toroidal grating monochromator

    International Nuclear Information System (INIS)

    Kurtz, R.L.; Ederer, D.L.; Barth, J.; Stockbauer, R.

    1988-01-01

    The performance of the 'high-flux' toroidal grating monochromator (HFTGM) at the NBS SURF-II synchrotron storage ring is assessed. Two gratings are studied: One with a ruled profile and the other having a laminar profile. The laminar profile is shown to reduce substantially the intensity of higher-order diffracted light with only a small decrease in the intensity of the first order light. The dependence of the energy resolution as a function of the area of the grating illuminated is also discussed. (orig.)

  2. Modification of the Undertow and Turbulence by Submerged Vegetation in a Laboratory Surf Zone

    Science.gov (United States)

    Mandel, T.; Suckale, J.; Marras, S.; Maldonado, S.; Koseff, J. R.

    2016-12-01

    Breaking waves in the surf zone are a dominant factor shaping the evolution of our coastlines. The turbulence generated by wave breaking causes sediment resuspension, while wave runup, rundown, and the undertow transport this sediment along and across the shore (Longo et al., 2002). Coastal hazard models must now address the added complications of climate change, including sea level rise, stronger storm events, and ecosystem degradation (Arkema et al., 2013). A robust theoretical understanding of surf zone dynamics is therefore imperative to considering the magnitude and implications of these potential changes. However, little work has been done to extend our current theoretical understanding to realistic beach faces, with aquatic vegetation, reefs, and other roughness elements that might mitigate scour and sedimentation. Clarifying these relationships will help scientists and policy-makers decide where to focus ecosystem restoration and preservation efforts, in order to maximize their protective benefits to infrastructure and economic activity on the coast. In order to evaluate the role of vegetation in coastal protection, we conducted a series of experiments in an idealized laboratory surf zone. We examine the impact of submerged model vegetation on the undertow profile, wave orbital velocities, turbulent kinetic energy, and wave-induced stresses, and compare these results to theoretical formulations that model these quantities. We find that vegetation reduces the wave energy available to be converted to turbulent kinetic energy during breaking, indicating a mechanism to mitigate suspension of sediment. Vegetation also reduces the magnitude of the undertow, likely reducing transport of sediment offshore. These results suggest that vegetation provides significant protective benefits for coastal communities at risk from erosion beyond its well-characterized ability to attenuate wave height, and motivate further work to incorporate these effects into models of near

  3. Diffraction and depths-of-field effects in electron beam imaging at SURF III

    International Nuclear Information System (INIS)

    Arp, U.

    2001-01-01

    Imaging an electron beam with visible light is a common method of diagnostics applied to electron accelerators. It is a straightforward way to deduce the transverse electron distribution as well as its changes over time. The electrons stored in the Synchrotron Ultraviolet Radiation Facility (SURF) III at the National Institute of Standards and Technology (NIST) were studied over an extended period of time to characterize the upgraded accelerator. There is good agreement between experimental and theoretical horizontal beam sizes at three different electron energies

  4. A status report on the SURF II synchrotron radiation facility at NBS

    International Nuclear Information System (INIS)

    Madden, R.P.

    1980-01-01

    Recent work to upgrade the SURF II (Synchrotron Ultraviolet Radiation Facility) storage ring is described, resulting in reliable operation up to 252 MeV at currents in the range 10-20 mA. A wide variety of experiments is now in progress at the facility, encompassing solid state physics, atomic and molecular physics and molecular biology, as well as the all-important radiometric standards work. The instrumentation used for these experiments is described; brief details of the experiments themselves are also given. (orig.)

  5. The Prevalence of Rough Sleeping and Sofa Surfing Amongst Young People in the UK

    OpenAIRE

    Clarke, Anna

    2016-01-01

    Whilst data on statutory homelessness is well recorded in the UK, there is a lack of data on informal homelessness (such as ‘sofa surfing’) and rough sleeping, other than that which relies on partial information and street counts. This paper presents findings from a recent online survey of young people and helps to fill this gap. It found that rates of sofa surfing and rough sleeping among young people were much higher than previously thought. Twenty-six percent of young people (aged 16–25) h...

  6. Habitats used by black and surf scoters in eastern North America as determined by satellite radio telemetry

    Science.gov (United States)

    Perry, M.C.; Kidwell, D.M.; Wells-Berlin, A. M.; Lohnes, E.J.R.; Olsen, Glenn H.; Osenton, P.C.

    2005-01-01

    Satellite radio telemetry was used to determine the movements and habitats of black scoters (Melanitta nigra) and surf scoters (Melanitta perspicillata) in eastern North America. A total of 21 surf scoters were instrumented during five years (2001-05) and 32 black scoters were instrumented during three years (2002-04) with implanted PTT 100 satellite transmitters (39 g) with external antenna. Nesting habitat of black scoters was more open than surf scoters (44% vs. 11%), whereas nesting habitat for surf scoters was located in more forested areas (66% vs. 20%). Locations of black scoters in breeding areas on average were at significantly higher latitude and lower elevations than sites used by surf scoters. Satellite telemetry determined that James Bay was the major molting area for male black and surf scoters, although some males molted along the coast of Labrador-Newfoundland. Black scoters instrumented on the Restigouche River, which is a major staging area, were widely distributed along the Atlantic Coast from Cape Cod to Georgia during winter. Major wintering areas for black scoters were Cape Cod (Martha's Vineyard and Nantucket Island), Long Island, and New Jersey. In these northern marine wintering areas, black scoters were located farther from shore (4.2 km) and in deeper water (8.3 m) than black scoters in more southern estuarine areas, where distance from shore was 3.1 km and water depth was 5.2 m. Surf scoters instrumented in Chesapeake Bay in late winter showed a strong tendency to return to the Bay the following winter after they had migrated to and from breeding areas. In Chesapeake Bay, black scoters and surf scoters were located mostly in mesohaline areas that had similar water depths (5.1 m vs. 7.5 m) and distances from shore (3.0 km vs. 2.9 km). Distance from shore and depth of water increased over time during the winter for both species. Updated information from the ARGOS Systems aboard the NOAA satellites on scoter movements was made accessible on

  7. Lead toxicosis in tundra swans near a mining and smelting complex in northern Idaho

    Science.gov (United States)

    Blus, L.J.; Henny, C.J.; Hoffman, D.J.; Grove, R.A.

    1991-01-01

    Die-offs of waterfowl have occurred in the Coeur d`Alene River system in northern Idaho since at least the early 1900`s. We investigated causes of mortality and lead and cadmium contamination of 46 tundra swans (Cygnus columbianus) from 1987 to 1989; an additional 22 swans found dead in 1990 were not examined. We necropsied 43 of the 46 birds found from 1987 to 1989; 38 of these were from the Coeur d`Alene River system, which has been contaminated with mining and smelting wastes for a century, and the other 5 were from a nearby, relatively uncontaminated area. Of the 36 livers of swans from the contaminated area that were analyzed, 32 contained lethal levels of lead (6 to 40 micrograms/g, wet weight) and all birds exhibited several symptoms of lead poisoning, notably enlarged gall bladders containing viscous, darkgreen bile. Only 13% of the lead-poisoned birds (10% when data were included from other studies of swans in the area) contained shot, compared to 95% of lead-poisoning swans in studies outside northern Idaho. Lead concentrations in blood samples from 16 apparently healthy swans (0.5 to 2.3 micrograms/g, and 4 leadpoisoned birds found moribund (1.3 to 9.6 micrograms/g) indicating that tundra swans accumulated high levels of lead from ingestion of sediment that contained up to 8,700 micrograms/g of lead and plants that contained up to 400 micrograms/g. The swans spend only a few weeks in the area staging during the spring migration. The five tundra swans from the uncontaminated area had low levels of lead and essentially no symptoms of lead poisoning.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Behavior of an indigenously fabricated transferred arc plasma furnace for smelting studies

    Science.gov (United States)

    A, K. MANDAL; R, K. DISHWAR; O, P. SINHA

    2018-03-01

    The utilization of industrial solid waste for metal recovery requires high-temperature tools due to the presence of silica and alumina, which is reducible at high temperature. In a plasma arc furnace, transferred arc plasma furnace (TAP) can meet all requirements, but the disadvantage of this technology is the high cost. For performing experiments in the laboratory, the TAP was fabricated indigenously in a laboratory based on the different inputs provided in the literature for the furnace design and fabrication. The observed parameters such as arc length, energy consumption, graphite electrode consumption, noise level as well as lining erosion were characterized for this fabricated furnace. The nitrogen plasma increased by around 200 K (200 °C) melt temperature and noise levels decreased by ∼10 dB compared to a normal arc. Hydrogen plasma offered 100 K (100 °C) higher melt temperature with ∼5 dB higher sound level than nitrogen plasma. Nitrogen plasma arc melting showed lower electrode and energy consumption than normal arc melting, whereas hydrogen plasma showed lower energy consumption and higher electrode consumption in comparison to nitrogen plasma. The higher plasma arc temperature resulted in a shorter meltdown time than normal arc with smoother arcing. Hydrogen plasma permitted more heats, reduced meltdown time, and lower energy consumption, but with increased graphite consumption and crucible wear. The present study showed that the fabricated arc plasma is better than the normal arc furnace with respect to temperature generation, energy consumption, and environmental friendliness. Therefore, it could be used effectively for smelting-reduction studies.

  9. Computational Fluid Dynamic Modeling of Zinc Slag Fuming Process in Top-Submerged Lance Smelting Furnace

    Science.gov (United States)

    Huda, Nazmul; Naser, Jamal; Brooks, Geoffrey; Reuter, Markus A.; Matusewicz, Robert W.

    2012-02-01

    Slag fuming is a reductive treatment process for molten zinciferous slags for extracting zinc in the form of metal vapor by injecting or adding a reductant source such as pulverized coal or lump coal and natural gas. A computational fluid dynamic (CFD) model was developed to study the zinc slag fuming process from imperial smelting furnace (ISF) slag in a top-submerged lance furnace and to investigate the details of fluid flow, reaction kinetics, and heat transfer in the furnace. The model integrates combustion phenomena and chemical reactions with the heat, mass, and momentum interfacial interaction between the phases present in the system. A commercial CFD package AVL Fire 2009.2 (AVL, Graz, Austria) coupled with a number of user-defined subroutines in FORTRAN programming language were used to develop the model. The model is based on three-dimensional (3-D) Eulerian multiphase flow approach, and it predicts the velocity and temperature field of the molten slag bath, generated turbulence, and vortex and plume shape at the lance tip. The model also predicts the mass fractions of slag and gaseous components inside the furnace. The model predicted that the percent of ZnO in the slag bath decreases linearly with time and is consistent broadly with the experimental data. The zinc fuming rate from the slag bath predicted by the model was validated through macrostep validation process against the experimental study of Waladan et al. The model results predicted that the rate of ZnO reduction is controlled by the mass transfer of ZnO from the bulk slag to slag-gas interface and rate of gas-carbon reaction for the specified simulation time studied. Although the model is based on zinc slag fuming, the basic approach could be expanded or applied for the CFD analysis of analogous systems.

  10. New approach for measuring 3D space by using Advanced SURF Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Youm, Minkyo; Min, Byungil; Suh, Kyungsuk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Backgeun [Sungkyunkwan Univ., Suwon (Korea, Republic of)

    2013-05-15

    The nuclear disasters compared to natural disaster create a more extreme condition for analyzing and evaluating. In this paper, measuring 3D space and modeling was studied by simple pictures in case of small sand dune. The suggested method can be used for the acquisition of spatial information by robot at the disaster area. As a result, these data are helpful for identify the damaged part, degree of damage and determination of recovery sequences. In this study we are improving computer vision algorithm for 3-D geo spatial information measurement. And confirm by test. First, we can get noticeable improvement of 3-D geo spatial information result by SURF algorithm and photogrammetry surveying. Second, we can confirm not only decrease algorithm running time, but also increase matching points through epi polar line filtering. From the study, we are extracting 3-D model by open source algorithm and delete miss match point by filtering method. However on characteristic of SURF algorithm, it can't find match point if structure don't have strong feature. So we will need more study about find feature point if structure don't have strong feature.

  11. Understanding successful and unsuccessful landings of aerial maneuver variations in professional surfing.

    Science.gov (United States)

    Forsyth, J R; Riddiford-Harland, D L; Whitting, J W; Sheppard, J M; Steele, J R

    2018-05-01

    Although performing aerial maneuvers can increase wave score and winning potential in competitive surfing, the critical features underlying successful aerial performance have not been systematically investigated. This study aimed to analyze highly skilled aerial maneuver performance and to identify the critical features associated with successful or unsuccessful landing. Using video recordings of the World Surf League's Championship Tour, every aerial performed during the quarterfinal, semifinal, and final heats from the 11 events in the 2015 season was viewed. From this, 121 aerials were identified with the Frontside Air (n = 15) and Frontside Air Reverse (n = 67) being selected to be qualitatively assessed. Using chi-squared analyses, a series of key critical features, including landing over the center of the surfboard (FS Air χ 2  = 14.00, FS Air Reverse χ 2  = 26.61; P < .001) and landing with the lead ankle in dorsiflexion (FS Air χ 2  = 3.90, FS Air Reverse χ 2  = 13.64; P < .05), were found to be associated with successful landings. These critical features help surfers land in a stable position, while maintaining contact with the surfboard. The results of this study provide coaches with evidence to adjust the technique of their athletes to improve their winning potential. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Robust and Effective Component-based Banknote Recognition by SURF Features.

    Science.gov (United States)

    Hasanuzzaman, Faiz M; Yang, Xiaodong; Tian, YingLi

    2011-01-01

    Camera-based computer vision technology is able to assist visually impaired people to automatically recognize banknotes. A good banknote recognition algorithm for blind or visually impaired people should have the following features: 1) 100% accuracy, and 2) robustness to various conditions in different environments and occlusions. Most existing algorithms of banknote recognition are limited to work for restricted conditions. In this paper we propose a component-based framework for banknote recognition by using Speeded Up Robust Features (SURF). The component-based framework is effective in collecting more class-specific information and robust in dealing with partial occlusion and viewpoint changes. Furthermore, the evaluation of SURF demonstrates its effectiveness in handling background noise, image rotation, scale, and illumination changes. To authenticate the robustness and generalizability of the proposed approach, we have collected a large dataset of banknotes from a variety of conditions including occlusion, cluttered background, rotation, and changes of illumination, scaling, and viewpoints. The proposed algorithm achieves 100% recognition rate on our challenging dataset.

  13. Longitudinal instability studies at the SURF II storage ring at NIST

    International Nuclear Information System (INIS)

    Harkay, K.C.; Sereno, N.S.

    1998-01-01

    Measurements of the longitudinal instability observed in the storage ring at the Synchrotrons Ultraviolet Radiation Facility (SURF II) at the National Institute of Standards and Technology (NET) were performed to understand the mechanism driving the instability. The instability, studied in depth by Ralcowsky and others, manifests itself in broad resonance features in the horizontal and vertical motion spectrum of the synchrotrons light from DC to a few kHz. Also observed are multiple synchrotrons harmonics that modulate the revolution harmonics; these are characteristic of longitudinal phase oscillations. These spectral features of the motion are found to be correlated with the periodic lengthening and shortening of the bunch length on time scales from approximately0.1 ms to 20 ms, depending on machine and radio-frequency (rf) system parameters. In this report, the growth rate of the instability is determined from measurements using an rf pickup electrode. The measured growth rates are compared to computed growth rates from an analytical model. Recommendations are made regarding options to control or mitigate the instability. In light of upgrade plans for SURF III, a few comments are presented about the beam lifetime

  14. Mechanical interactions in bacterial colonies and the surfing probability of beneficial mutations

    Science.gov (United States)

    Farrell, Fred D.

    2017-01-01

    Bacterial conglomerates such as biofilms and microcolonies are ubiquitous in nature and play an important role in industry and medicine. In contrast to well-mixed cultures routinely used in microbial research, bacteria in a microcolony interact mechanically with one another and with the substrate to which they are attached. Here, we use a computer model of a microbial colony of rod-shaped cells to investigate how physical interactions between cells determine their motion in the colony and how this affects biological evolution. We show that the probability that a faster-growing mutant ‘surfs’ at the colony's frontier and creates a macroscopic sector depends on physical properties of cells (shape, elasticity and friction). Although all these factors contribute to the surfing probability in seemingly different ways, their effects can be summarized by two summary statistics that characterize the front roughness and cell alignment. Our predictions are confirmed by experiments in which we measure the surfing probability for colonies of different front roughness. Our results show that physical interactions between bacterial cells play an important role in biological evolution of new traits, and suggest that these interactions may be relevant to processes such as de novo evolution of antibiotic resistance. PMID:28592660

  15. A model for the generation of two-dimensional surf beat

    Science.gov (United States)

    List, Jeffrey H.

    1992-01-01

    A finite difference model predicting group-forced long waves in the nearshore is constructed with two interacting parts: an incident wave model providing time-varying radiation stress gradients across the nearshore, and a long-wave model which solves the equations of motion for the forcing imposed by the incident waves. Both shallow water group-bound long waves and long waves generated by a time-varying breakpoint are simulated. Model-generated time series are used to calculate the cross correlation between wave groups and long waves through the surf zone. The cross-correlation signal first observed by Tucker (1950) is well predicted. For the first time, this signal is decomposed into the contributions from the two mechanisms of leaky mode forcing. Results show that the cross-correlation signal can be explained by bound long waves which are amplified, though strongly modified, through the surf zone before reflection from the shoreline. The breakpoint-forced long waves are added to the bound long waves at a phase of pi/2 and are a secondary contribution owing to their relatively small size.

  16. Turbulent stresses in the surf-zone: Which way is up?

    Science.gov (United States)

    Haines, John W.; Gelfenbaum, Guy; Edge, B.L

    1997-01-01

    Velocity observations from a vertical stack of three-component Acoustic Doppler Velocimeters (ADVs) within the energetic surf-zone are presented. Rapid temporal sampling and small sampling volume provide observations suitable for investigation of the role of turbulent fluctuations in surf-zone dynamics. While sensor performance was good, failure to recover reliable measures of tilt from the vertical compromise the data value. We will present some cursory observations supporting the ADV performance, and examine the sensitivity of stress estimates to uncertainty in the sensor orientation. It is well known that turbulent stress estimates are highly sensitive to orientation relative to vertical when wave motions are dominant. Analyses presented examine the potential to use observed flow-field characteristics to constrain sensor orientation. Results show that such an approach may provide a consistent orientation to a fraction of a degree, but the inherent sensitivity of stress estimates requires a still more restrictive constraint. Regardless, the observations indicate the degree to which stress estimates are dependent on orientation, and provide some indication of the temporal variability in time-averaged stress estimates.

  17. Verification test of the SURF and SURFplus models in xRage

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-18

    As a verification test of the SURF and SURFplus models in the xRage code we use a propagating underdriven detonation wave in 1-D. This is about the only test cases for which an accurate solution can be determined based on the theoretical structure of the solution. The solution consists of a steady ZND reaction zone profile joined with a scale invariant rarefaction or Taylor wave and followed by a constant state. The end of the reaction profile and the head of the rarefaction coincide with the sonic CJ state of the detonation wave. The constant state is required to match a rigid wall boundary condition. For a test case, we use PBX 9502 with the same EOS and burn rate as previously used to test the shock detector algorithm utilized by the SURF model. The detonation wave is propagated for 10 μs (slightly under 80mm). As expected, the pointwise errors are largest in the neighborhood of discontinuities; pressure discontinuity at the lead shock front and pressure derivative discontinuities at the head and tail of the rarefaction. As a quantitative measure of the overall accuracy, the L2 norm of the difference of the numerical pressure and the exact solution is used. Results are presented for simulations using both a uniform grid and an adaptive grid that refines the reaction zone.

  18. Lower-Body Muscle Structure and Jump Performance of Stronger and Weaker Surfing Athletes.

    Science.gov (United States)

    Secomb, Josh L; Nimphius, Sophia; Farley, Oliver R; Lundgren, Lina; Tran, Tai T; Sheppard, Jeremy M

    2016-07-01

    To identify whether there are any significant differences in the lower-body muscle structure and countermovement-jump (CMJ) and squat-jump (SJ) performance between stronger and weaker surfing athletes. Twenty elite male surfers had their lower-body muscle structure assessed with ultrasonography and completed a series of lower-body strength and jump tests including isometric midthigh pull (IMTP), CMJ, and SJ. Athletes were separated into stronger (n = 10) and weaker (n = 10) groups based on IMTP performance. Large significant differences were identified between the groups for vastus lateralis (VL) thickness (P = .02, ES = 1.22) and lateral gastrocnemius (LG) pennation angle (P = .01, ES = 1.20), and a large nonsignificant difference was identified in LG thickness (P = .08, ES = 0.89). Furthermore, significant differences were present between the groups for peak force, relative peak force, and jump height in the CMJ and SJ (P Stronger surfing athletes in this study had greater VL and LG thickness and LG pennation angle. These muscle structures may explain their better performance in the CMJ and SJ. A unique finding in this study was that the stronger group appeared to better use their strength and muscle structure for braking as they had significantly higher eccentric peak velocity and vertical displacement during the CMJ. This enhanced eccentric phase may have resulted in a greater production and subsequent utilization of stored elastic strain energy that led to the significantly better CMJ performance in the stronger group.

  19. Comparison of impact forces, accelerations and ankle range of motion in surfing-related landing tasks.

    Science.gov (United States)

    Lundgren, Lina E; Tran, Tai T; Nimphius, Sophia; Raymond, Ellen; Secomb, Josh L; Farley, Oliver R L; Newton, Robert U; Sheppard, Jeremy M

    2016-01-01

    This study aimed to describe the impact forces, accelerations and ankle range of motion in five different landing tasks that are used in training and testing for competitive surfing athletes, to assist coaches in the prescription of landing task progression and monitoring training load. Eleven competitive surfing athletes aged 24 ± 7 years participated, and inertial motion sensors were fixed to the anterior aspect of the feet, mid-tibial shafts, sacrum and eighth thoracic vertebrae on these athletes. Three tasks were performed landing on force plates and two tasks in a modified gymnastics set-up used for land-based aerial training. Peak landing force, resultant peak acceleration and front and rear side ankle dorsiflexion ranges of motion during landing were determined. The peak acceleration was approximately 50% higher when performing aerial training using a mini-trampoline and landing on a soft-density foam board, compared to a similar landing off a 50 cm box. Furthermore, the ankle ranges of motion during the gymnastic type landings were significantly lower than the other landing types (P ≤ 0.05 and P ≤ 0.001), for front and rear sides, respectively. Conclusively, increased task complexity and specificity of the sport increased the tibial peak acceleration, indicating greater training load.

  20. Can Silicon-Smelting Contribute to the Low O/Si Ratio on the Surface of Mercury?

    Science.gov (United States)

    McCubbin, F. M.; Vander Kaaden, K. E.; Hogancamp, J.; Archer, P. D., Jr.; Boyce, J. W.

    2018-01-01

    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft collected data that provided important insights into the structure, chemical makeup, and compositional diversity of Mercury. Among the many discoveries about Mercury made by MESSENGER, several surprising compositional characteristics of the surface were observed. These discoveries include elevated sulfur abundances (up to 4 wt.%), elevated abundances of graphitic carbon (0-4.1 wt.% across the surface with an additional 1-3 wt.% graphite above the global average in low reflectance materials), low iron abundances (less than 2 wt.%), and low oxygen abundances (O/Si weight ratio of 1.20+/-0.1). These exotic characteristics likely have important implications for the thermochemical evolution of Mercury and point to a planet that formed under highly reducing conditions. In the present study, we focus specifically on the low O/Si ratio of Mercury, which is anomalous compared to all other planetary materials. A recent study that considered the geochemical implications of the low O/Si ratio reported that 12-20% of the surface materials on Mercury are composed of Si-rich, Si-Fe alloys. They further postulated that the origin of the metal is best explained by a combination of space weathering and graphite-induced smelting that was facilitated by interaction of graphite with boninitic and komatiitic parental liquids. The goal of the present study is to assess the plausibility of smelting on Mercury through experiments run at the conditions that McCubbin et al. indicated would be favorable for Si-smelting.

  1. A Water Model Study on Mixing Behavior of the Two-Layered Bath in Bottom Blown Copper Smelting Furnace

    Science.gov (United States)

    Shui, Lang; Cui, Zhixiang; Ma, Xiaodong; Jiang, Xu; Chen, Mao; Xiang, Yong; Zhao, Baojun

    2018-05-01

    The bottom-blown copper smelting furnace is a novel copper smelter developed in recent years. Many advantages of this furnace have been found, related to bath mixing behavior under its specific gas injection scheme. This study aims to use an oil-water double-phased laboratory-scale model to investigate the impact of industry-adjustable variables on bath mixing time, including lower layer thickness, gas flow rate, upper layer thickness and upper layer viscosity. Based on experimental results, an overall empirical relationship of mixing time in terms of these variables has been correlated, which provides the methodology for industry to optimize mass transfer in the furnace.

  2. Effect of Copper and Iron Ions on the Sulphidizing Flotation of Copper Oxide in Copper Smelting Slag

    OpenAIRE

    Qing-qing Pan; Hui-qing Peng

    2018-01-01

    The treatment of smelting slag has attracted much attention nowadays. This study investigates the influence of Na2S, CuSO4, and FeCl3 on sulphidizing flotation of copper oxide. The results show that a proper Cu2+ concentration can increase the sulphidizing effect of copper oxide, while Fe3+ inhibits the sulphidizing effect. Further analysis shows that Cu2+ ions can reduce the surface potential, increase the S2− adsorption, then generate more polysulfide, and therefore promote the sulphidizing...

  3. Element Distribution in the Oxygen-Rich Side-Blow Bath Smelting of a Low-Grade Bismuth-Lead Concentrate

    Science.gov (United States)

    Yang, Tianzu; Xiao, Hui; Chen, Lin; Chen, Wei; Liu, Weifeng; Zhang, Duchao

    2018-03-01

    Oxygen-rich side-blow bath smelting (OSBS) technology offers an efficient method for processing complex bismuth-lead concentrates; however, the element distributions in the process remain unclear. This work determined the distributions of elements, i.e., bismuth, lead, silver, copper, arsenic and antimony, in an industrial-scale OSBS process. The feed, oxidized slag and final products were collected from the respective sampling points and analyzed. For the oxidative smelting process, 65% of bismuth and 76% of silver in the concentrate report to the metal alloy, whereas less lead reports to the metal ( 31%) than the oxidized slag ( 44%). Approximately 50% of copper enters the matte, while more than 63% of arsenic and antimony report to the slag. For the reductive smelting process, less than 4.5% of bismuth, lead, silver and copper in the oxidized slag enter the reduced slag, indicating high recoveries of these metal values.

  4. Comparative growth models of big-scale sand smelt (Atherina boyeri Risso, 1810 sampled from Hirfanll Dam Lake, Klrsehir, Ankara, Turkey

    Directory of Open Access Journals (Sweden)

    S. Benzer

    2017-06-01

    Full Text Available In this current publication the growth characteristics of big-scale sand smelt data were compared for population dynamics within artificial neural networks and length-weight relationships models. This study aims to describe the optimal decision of the growth model of big-scale sand smelt by artificial neural networks and length-weight relationships models at Hirfanll Dam Lake, Klrsehir, Turkey. There were a total of 1449 samples collected from Hirfanll Dam Lake between May 2015 and May 2016. Both model results were compared with each other and the results were also evaluated with MAPE (mean absolute percentage error, MSE (mean squared error and r2 (coefficient correlation data as a performance criterion. The results of the current study show that artificial neural networks is a superior estimation tool compared to length-weight relationships models of big-scale sand smelt in Hirfanll Dam Lake.

  5. Norman-based Isolated Data Systems allows users to surf the Internet with no traceable IP address

    CERN Multimedia

    2004-01-01

    "Patented by Norman-based Isolated Data Systems, John Doe is an anonymous proxy server that allows users to surf the Internet exactly as before, with one exception - they are identifiable only as John Doe, with no traceable IP address, which means no tracking, no identification and no profile building" ( 1/2 page)

  6. Data on cytochrome c oxidase assembly in mice and human fibroblasts or tissues induced by SURF1 defect

    Czech Academy of Sciences Publication Activity Database

    Kovářová, Nikola; Pecina, Petr; Nůsková, Hana; Vrbacký, Marek; Zeviani, M.; Mráček, Tomáš; Viscomi, C.; Houštěk, Josef

    2016-01-01

    Roč. 7, June 01 (2016), s. 1004-1009 ISSN 2352-3409 R&D Projects: GA ČR(CZ) GB14-36804G; GA MŠk(CZ) LL1204; GA MZd(CZ) NT12370 Institutional support: RVO:67985823 Keywords : cytochrome c oxidase * respiratory chain * SURF1 * knockout * doxycycline Subject RIV: EB - Genetics ; Molecular Biology

  7. O SISTEMA DE OPERAÇÃO DO SERVIÇO DE SURFE NO RIO DE JANEIRO

    Directory of Open Access Journals (Sweden)

    Débora Andrade de Castro

    2017-01-01

    Full Text Available Surfing arrived in Brazil in 1938, giving rise to the first national surfers. By the 1970s, the sports had evolved into both a social and market structure, specifically in the states of Rio de Janeiro, São Paulo and Rio Grande do Sul, where surfboard producers, importers of materials and raw materials, promotion of championships and sporting events, as well as major brands and specialist stores began to open, starting a growing trend of new products and services. This paper analyzes the management operation of the surfing service sector in the State of Rio de Janeiro, and seeks to understand the complex relations between components, to explore those connections and make suggestions for future opportunities. The results show that Brazil is a strong consumer market of goods and services related to surfing due to the climate, young population, of which the majority lives close to the coast, features that are especially strong in Rio de Janeiro state. Among the factors that contribute to the development of surfing in Brazil is its insertion into the general media, in particular its projected image as a young and exciting activity, whose practice is related to psychological factors such as emotion, control of the external environment and overcoming challenges. The products and services that enable the consumer to overcome there physical and psychological challenges with the objective of achieving stronger control over these factors reveals growing possibilities for business and innovation.

  8. Concentrations and temporal variations of /sup 210/Po, /sup 210/Pb, and Al in the surf zone ecosystem of Copalis Beach, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, J T; Carpenter, R

    1979-01-01

    Surf diatoms monitored during a 21-month period at Copalis Beach, Washington, contained elevated concentrations of Al, /sup 210/Pb, and supported /sup 210/Po compared to net phytoplankton from Washington coastal waters and Puget Sound. Aluminum concentrations of several percent dry weight found in the surf diatoms were not a reflection of contamination by discrete inorganic particulate matter but were the result of a natural coating of clay-sized particles on Chaetoceros armatum, the predominant diatom in the surfblooms. A high correlation between Al and /sup 210/Pb in the surf diatoms suggests /sup 210/Pb and supported /sup 210/Po were also associated with the clay-sized particles. During fall through spring, the unsupported /sup 210/Po concentrations in the surf diatoms were correlated with the input of /sup 210/Po by precipitation. A summer maximum in unsupported /sup 210/Po concentrations in the surf diatoms may reflect upwelling that causes higher dissolved /sup 210/Po concentrations in the summer surf relative to those of late spring and early fall. The consumers of the surf diatoms exhibited larger /sup 210/Po-activity-to-/sup 210/Pb-activity ratios than their food, indicating /sup 210/Po was preferentially accumulated in the higher trophic level.

  9. Surf Utopia

    OpenAIRE

    Goffin, Jeremy

    2016-01-01

    With swell data at our finger tips, the what where when and how drives the daily search bars. Being lucky enough to catch the wind and waves together are what dreams are made of. Whilst visually deconstructing the perfect conditions I've focused the elements down to the main details. Size, Swell Period, Temperature and Wind Speed manages the core information whilst leaving out the politics of the on or off shore debates. Either in board shorts or in a thermal wet suit, big gnarly...

  10. Dynamic variation of histone H3 trimethyl Lys4 (H3K4me3) and heterochromatin protein 1 (HP1) with employment length in nickel smelting workers.

    Science.gov (United States)

    Zhao, Yanhong; Cheng, Ning; Dai, Min; Pu, Hongquan; Zheng, Tongzhang; Li, Haiyan; He, Jie; Bai, Yana

    2017-07-01

    To investigate the dynamic variation in H3K4me3 and HP1 with employment length in nickel smelting workers. Blood samples were collected from 140 nickel smelting workers and 140 age-matched office workers to test for H3K4me3, and HP1 levels. H3K4me3 was statistically significantly different (p exposure to nickel can induce oxidative damage, and increase H3K4me3 expression and inhibit HP1 expression.

  11. Quantifying Wave Breaking Shape and Type in the Surf-Zone Using LiDAR

    Science.gov (United States)

    Albright, A.; Brodie, K. L.; Hartzell, P. J.; Glennie, C. L.

    2017-12-01

    Waves change shape as they shoal and break across the surf-zone, ultimately dissipating and transferring their energy into turbulence by either spilling or plunging. This injection of turbulence and changes in wave shape can affect the direction of sediment transport at the seafloor, and ultimately lead to morphological evolution. Typical methods for collecting wave data in the surf-zone include in-situ pressure gauges, velocimeters, ultrasonic sensors, and video imagery. Drawbacks to these data collection methods are low spatial resolution of point measurements, reliance on linear theory to calculate sea-surface elevations, and intensive computations required to extract wave properties from stereo 2D imagery. As a result, few field measurements of the shapes of plunging and/or spilling breakers exist, and existing knowledge is confined to results of laboratory studies. We therefore examine the use of a multi-beam scanning Light Detection and Ranging (LiDAR) remote sensing instrument with the goal of classifying the breaking type of propagating waves in the surf-zone and quantitatively determining wave morphometric properties. Data were collected with a Velodyne HDL-32E LiDAR scanner (360° vertical field of view) mounted on an arm of the Coastal Research Amphibious Buggy (CRAB) at the U.S. Army Corps of Engineers Field Research Facility in Duck, North Carolina. Processed laser scan data are used to visualize the lifecycle of a wave (shoaling, breaking, broken) and identify wave types (spilling, plunging, non-breaking) as they pass beneath the scanner. For each rotation of the LiDAR scanner, the point cloud data are filtered, smoothed, and detrended in order to identify individual waves and measure their properties, such as speed, height, period, upward/downward slope, asymmetry, and skewness. The 3D nature of point cloud data is advantageous for research, because it enables viewing from any angle. In our analysis, plan views are used to separate individual waves

  12. Effects of ocean acidification on the swimming ability, development and biochemical responses of sand smelt larvae

    International Nuclear Information System (INIS)

    Silva, Cátia S.E.; Novais, Sara C.; Lemos, Marco F.L.; Mendes, Susana; Oliveira, Ana P.; Gonçalves, Emanuel J.; Faria, Ana M.

    2016-01-01

    Ocean acidification, recognized as a major threat to marine ecosystems, has developed into one of the fastest growing fields of research in marine sciences. Several studies on fish larval stages point to abnormal behaviours, malformations and increased mortality rates as a result of exposure to increased levels of CO_2. However, other studies fail to recognize any consequence, suggesting species-specific sensitivity to increased levels of CO_2, highlighting the need of further research. In this study we investigated the effects of exposure to elevated pCO_2 on behaviour, development, oxidative stress and energy metabolism of sand smelt larvae, Atherina presbyter. Larvae were caught at Arrábida Marine Park (Portugal) and exposed to different pCO_2 levels (control: ~ 600 μatm, pH = 8.03; medium: ~ 1000 μatm, pH = 7.85; high: ~ 1800 μatm, pH = 7.64) up to 15 days, after which critical swimming speed (U_c_r_i_t), morphometric traits and biochemical biomarkers were determined. Measured biomarkers were related with: 1) oxidative stress — superoxide dismutase and catalase enzyme activities, levels of lipid peroxidation and DNA damage, and levels of superoxide anion production; 2) energy metabolism — total carbohydrate levels, electron transport system activity, lactate dehydrogenase and isocitrate dehydrogenase enzyme activities. Swimming speed was not affected by treatment, but exposure to increasing levels of pCO_2 leads to higher energetic costs and morphometric changes, with larger larvae in high pCO_2 treatment and smaller larvae in medium pCO_2 treatment. The efficient antioxidant response capacity and increase in energetic metabolism only registered at the medium pCO_2 treatment may indicate that at higher pCO_2 levels the capacity of larvae to restore their internal balance can be impaired. Our findings illustrate the need of using multiple approaches to explore the consequences of future pCO_2 levels on organisms. - Highlights: • Exposure to high pCO_2

  13. Effects of ocean acidification on the swimming ability, development and biochemical responses of sand smelt larvae

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cátia S.E. [MARE — Marine and Environmental Sciences Centre, ISPA − Instituto Universitário (Portugal); MARE — Marine and Environmental Sciences Centre, ESTM, Instituto Politécnico de Leiria (Portugal); Novais, Sara C.; Lemos, Marco F.L.; Mendes, Susana [MARE — Marine and Environmental Sciences Centre, ESTM, Instituto Politécnico de Leiria (Portugal); Oliveira, Ana P. [IPMA — Instituto Português do Mar e da Atmosfera, Algés (Portugal); Gonçalves, Emanuel J. [MARE — Marine and Environmental Sciences Centre, ISPA − Instituto Universitário (Portugal); Faria, Ana M., E-mail: afaria@ispa.pt [MARE — Marine and Environmental Sciences Centre, ISPA − Instituto Universitário (Portugal)

    2016-09-01

    Ocean acidification, recognized as a major threat to marine ecosystems, has developed into one of the fastest growing fields of research in marine sciences. Several studies on fish larval stages point to abnormal behaviours, malformations and increased mortality rates as a result of exposure to increased levels of CO{sub 2}. However, other studies fail to recognize any consequence, suggesting species-specific sensitivity to increased levels of CO{sub 2}, highlighting the need of further research. In this study we investigated the effects of exposure to elevated pCO{sub 2} on behaviour, development, oxidative stress and energy metabolism of sand smelt larvae, Atherina presbyter. Larvae were caught at Arrábida Marine Park (Portugal) and exposed to different pCO{sub 2} levels (control: ~ 600 μatm, pH = 8.03; medium: ~ 1000 μatm, pH = 7.85; high: ~ 1800 μatm, pH = 7.64) up to 15 days, after which critical swimming speed (U{sub crit}), morphometric traits and biochemical biomarkers were determined. Measured biomarkers were related with: 1) oxidative stress — superoxide dismutase and catalase enzyme activities, levels of lipid peroxidation and DNA damage, and levels of superoxide anion production; 2) energy metabolism — total carbohydrate levels, electron transport system activity, lactate dehydrogenase and isocitrate dehydrogenase enzyme activities. Swimming speed was not affected by treatment, but exposure to increasing levels of pCO{sub 2} leads to higher energetic costs and morphometric changes, with larger larvae in high pCO{sub 2} treatment and smaller larvae in medium pCO{sub 2} treatment. The efficient antioxidant response capacity and increase in energetic metabolism only registered at the medium pCO{sub 2} treatment may indicate that at higher pCO{sub 2} levels the capacity of larvae to restore their internal balance can be impaired. Our findings illustrate the need of using multiple approaches to explore the consequences of future pCO{sub 2} levels on

  14. Allocation and source attribution of lead and cadmium in maize (Zea mays L.) impacted by smelting emissions

    International Nuclear Information System (INIS)

    Bi Xiangyang; Feng Xinbin; Yang Yuangen; Li Xiangdong; Shin, Grace P.Y.; Li Feili; Qiu Guangle; Li Guanghui; Liu Taoze; Fu Zhiyou

    2009-01-01

    Plants grown in contaminated areas may accumulate trace metals to a toxic level via their roots and/or leaves. In the present study, we investigated the distribution and sources of Pb and Cd in maize plants (Zea mays L.) grown in a typical zinc smelting impacted area of southwestern China. Results showed that the smelting activities caused significantly elevated concentrations of Pb and Cd in the surrounding soils and maize plants. Pb isotope data revealed that the foliar uptake of atmospheric Pb was the dominant pathway for Pb to the leaf and grain tissues of maize, while Pb in the stalk and root tissues was mainly derived from root uptake. The ratio of Pb to Cd concentrations in the plants indicated that Cd had a different behavior from Pb, with most Cd in the maize plants coming from the soil via root uptake. - The sources and pathways of Pb and Cd accumulated in maize were assessed using Pb isotopes and Pb/Cd ratios

  15. Bioleaching mechanism of Zn, Pb, In, Ag, Cd and As from Pb/Zn smelting slag by autotrophic bacteria.

    Science.gov (United States)

    Wang, Jia; Huang, Qifei; Li, Ting; Xin, Baoping; Chen, Shi; Guo, Xingming; Liu, Changhao; Li, Yuping

    2015-08-15

    A few studies have focused on release of valuable/toxic metals from Pb/Zn smelting slag by heterotrophic bioleaching using expensive yeast extract as an energy source. The high leaching cost greatly limits the practical potential of the method. In this work, autotrophic bioleaching using cheap sulfur or/and pyrite as energy matter was firstly applied to tackle the smelting slag and the bioleaching mechanisms were explained. The results indicated autotrophic bioleaching can solubilize valuable/toxic metals from slag, yielding maximum extraction efficiencies of 90% for Zn, 86% for Cd and 71% for In, although the extraction efficiencies of Pb, As and Ag were poor. The bioleaching performance of Zn, Cd and Pb was independent of leaching system, and leaching mechanism was acid dissolution. A maximum efficiency of 25% for As was achieved by acid dissolution in sulfursulfur oxidizing bacteria (S-SOB), but the formation of FeAsO4 reduced extraction efficiency in mixed energy source - mixed culture (MS-MC). Combined works of acid dissolution and Fe(3+) oxidation in MS-MC was responsible for the highest extraction efficiency of 71% for In. Ag was present in the slag as refractory AgPb4(AsO4)3 and AgFe2S3, so extraction did not occur. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Allocation and source attribution of lead and cadmium in maize (Zea mays L.) impacted by smelting emissions

    Energy Technology Data Exchange (ETDEWEB)

    Bi Xiangyang [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Key Laboratory of Biogeology and Environmental Geology, Ministry of Education, China University of Geosciences, Wuhan 430074 (China); Feng Xinbin [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)], E-mail: fengxinbin@vip.skleg.cn; Yang Yuangen [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Li Xiangdong; Shin, Grace P.Y. [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Li Feili [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Qiu Guangle; Li Guanghui; Liu Taoze; Fu Zhiyou [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)

    2009-03-15

    Plants grown in contaminated areas may accumulate trace metals to a toxic level via their roots and/or leaves. In the present study, we investigated the distribution and sources of Pb and Cd in maize plants (Zea mays L.) grown in a typical zinc smelting impacted area of southwestern China. Results showed that the smelting activities caused significantly elevated concentrations of Pb and Cd in the surrounding soils and maize plants. Pb isotope data revealed that the foliar uptake of atmospheric Pb was the dominant pathway for Pb to the leaf and grain tissues of maize, while Pb in the stalk and root tissues was mainly derived from root uptake. The ratio of Pb to Cd concentrations in the plants indicated that Cd had a different behavior from Pb, with most Cd in the maize plants coming from the soil via root uptake. - The sources and pathways of Pb and Cd accumulated in maize were assessed using Pb isotopes and Pb/Cd ratios.

  17. High-Temperature Oxidation and Smelt Deposit Corrosion of Ni-Cr-Ti Arc-Sprayed Coatings

    Science.gov (United States)

    Matthews, S.; Schweizer, M.

    2013-08-01

    High Cr content Ni-Cr-Ti arc-sprayed coatings have been extensively applied to mitigate corrosion in black liquor recovery boilers in the pulp and paper industry. In a previous article, the effects of key spray parameters on the coating's microstructure and its composition were investigated. Three coating microstructures were selected from that previous study to produce a dense, oxidized coating (coating A), a porous, low oxide content coating (coating B), and an optimized coating (coating C) for corrosion testing. Isothermal oxidation trials were performed in air at 550 and 900 °C for 30 days. Additional trials were performed under industrial smelt deposits at 400 and 800 °C for 30 days. The effect of the variation in coating microstructure on the oxidation and smelt's corrosion response was investigated through the characterization of the surface corrosion products, and the internal coating microstructural developments with time at high temperature. The effect of long-term, high-temperature exposure on the interaction between the coating and substrate was characterized, and the mechanism of interdiffusion was discussed.

  18. Assessing mobility and redistribution patterns of sand and oil agglomerates in the surf zone

    Science.gov (United States)

    Dalyander, P. Soupy; Long, Joesph W.; Plant, Nathaniel G.; Thompson, David M.

    2014-01-01

    Heavier-than-water sand and oil agglomerates that formed in the surf zone following the Deepwater Horizon oil spill continued to cause beach re-oiling 3 years after initial stranding. To understand this phenomena and inform operational response now and for future spills, a numerical method to assess the mobility and alongshore movement of these “surface residual balls” (SRBs) was developed and applied to the Alabama and western Florida coasts. Alongshore flow and SRB mobility and potential flux were used to identify likely patterns of transport and deposition. Results indicate that under typical calm conditions, cm-size SRBs are unlikely to move alongshore, whereas mobility and transport is likely during storms. The greater mobility of sand compared to SRBs makes burial and exhumation of SRBs likely, and inlets were identified as probable SRB traps. Analysis of field data supports these model results.

  19. Experimental study on thermal dispersion in and near the surf zone

    International Nuclear Information System (INIS)

    Komori, Shuzo; Tanaka, Hiroyoshi; Wada, Akira

    1978-01-01

    The site of Fukushima No. 1 Nuclear Power Station of Tokyo Electric Power Company was selected, and first, irregular waves with the typical wave spectra (in usual time and in storm time) in the sea region of the site were reproduced in the hydraulic model, then the characteristics of thermal dispersion and the velocityfield of warmed water (its discharge is 25.3 m 3 /sec.) in and near the surf zone under the action of those irregular waves were discussed. Finally, the similarity was investigated between the dispersion phenomenon in the hydraulic model and that in the prototype by comparing the experimental results of the dispersion range of warmed water with the results of field measurements. It may be concluded that the enveloped range of thermal dispersion in prototype can be predicted fairly correctly under almost the same discharge condition as this experiment if the prototype conditions of waves and currents are considered carefully and reproduced in a hydraulic model. (Kobatake, H.)

  20. Modified SURF Algorithm Implementation on FPGA For Real-Time Object Tracking

    Directory of Open Access Journals (Sweden)

    Tomyslav Sledevič

    2013-05-01

    Full Text Available The paper describes the FPGA-based implementation of the modified speeded-up robust features (SURF algorithm. FPGA was selected for parallel process implementation using VHDL to ensure features extraction in real-time. A sliding 84×84 size window was used to store integral pixels and accelerate Hessian determinant calculation, orientation assignment and descriptor estimation. The local extreme searching was used to find point of interest in 8 scales. The simplified descriptor and orientation vector were calculated in parallel in 6 scales. The algorithm was investigated by tracking marker and drawing a plane or cube. All parts of algorithm worked on 25 MHz clock. The video stream was generated using 60 fps and 640×480 pixel camera.Article in Lithuanian

  1. New application of the radioactive tracer method for sediment movement measurements in the surf zone

    International Nuclear Information System (INIS)

    Owczarczyk, A.; Strzelecki, M.; Szpilowski, S.; Wierzchnicki, R.; Basinski, T.

    1989-01-01

    The investigations of sediment movement with the use of radiotracers have been carried out in a surf zone of Lubiatowo. Inception of sand motion and sediment transport velocity were the objective of the experiment. The spider type construction was located at the depth of 0.7 m. An artificial sand made of iridium glass (γ = 2.660 kg/m 3 ) containing 0.25 weight per cent of 192 Ir was used as a tracer. The fraction of 0.15 to 0.20 mm has been chosen as the representative diameter of sand grains existing at the investigated bottom region. The inception of sand movement versus current velocity and wave conditions as well as displacement velocity of tracer mass were determined. An improved construction was designed and tested. (author)

  2. Measurement of synchrotron radiation from the NBS SURF II using a silicon radiometer

    International Nuclear Information System (INIS)

    Schaefer, A.R.

    1980-01-01

    A project is described in which the synchrotron radiation output from the NBS storage ring known as SURF II, is measured using a well characterized silicon based radiometer. This device consists of a silicon photodiode coupled with two interference filters to restrict the spectral response to a finite and convenient spectral region for the measurement. Considerations required for the characterization of the radiometer will be discussed. The absolute radiant flux from the storage ring is also calculable from various machine parameters. A measurement of the number of circulating electrons will be derived from electron counting techniques at low levels. This will yield an important intercomparison between the synchrotron flux measurements determined in two entirely different ways. (orig.)

  3. Surfer's myelopathy: a rare presentation in a non-surfing setting and review of the literature.

    Science.gov (United States)

    Maharaj, Monish M; Phan, Kevin; Hariswamy, Soumya; Rao, Prashanth J

    2016-09-01

    Surfers myelopathy can be a rapidly devastating disease and little is known surrounding the pathophysiology of the condition. Although the classical pattern of illness has been well reported, it has never been observed in a non-surfing setting. A 51-year-old demolition worker presented with acute non-traumatic myelopathy. Clinical examination revealed sensory loss to the level of L2. T2-MRI and MRI-DWI revealed a hyperintense signal suggestive of an ischaemic event. A diagnosis of surfer's myelopathy was made and he was commenced on steroid therapy. Following steroid therapy and fluid management the patient was discharged after 6 days with minor anaethesia but significant overall neurological improvement. Diagnosis of SM requires a thorough history, clinical examination and imaging (MRI, MRI-DWI). The patient should be admitted early and investigated. The use of rehabilitation services may be useful if available.

  4. French policy localism: Surfing on ‘Positive Energie Territories’ (Tepos)

    International Nuclear Information System (INIS)

    Nadaï, Alain; Labussière, Olivier; Debourdeau, Ariane; Régnier, Yannick; Cointe, Béatrice; Dobigny, Laure

    2015-01-01

    This paper is interested in sustainable energy initiatives in French rural areas. It follows up the UK debate about ‘localism’. UK policy localism has been cast as neoliberal, framing communities as competent and competitive actors, morally responsible and accountable for their destiny. In France, the emerging policy localism is surfing on an ongoing political structuration of innovative rural territories – ‘Positive Energie Territories’ (TEPOS). The paper presents and discusses the results of a rough census (undertaken in 2012) of significant experiences in this domain. It points to a few experiences and depicts them as risky, trial-and-error transcalar processes that endow locally emergent energy issues with a political dimension. To this extent, they amount to a different way of doing energy policy. The analysis points to an ambiguity in French policy localism. This localism may pave the way for an upscaling of the ongoing TEPOS political structuration, or tend to make TEPOS into demonstration territories within a neoliberal RTD policy approach. In the latter case, it may not necessarily fit territories to pursue their political structuration with a view to the energy transition. - Highlights: • The paper bears witness to the emergence of a French energy policy localism. • It presents a sample of significant local rural experiences in the climate energy domain in rural France. • These experiences are risky, trial-and-error transcalar processes. • They amount to a different way of doing energy policy. • French localism surfs on these innovative territories while remaining ambiguous about the status that it confers on them

  5. Object Recognition System in Remote Controlled Weapon Station using SIFT and SURF Methods

    Directory of Open Access Journals (Sweden)

    Midriem Mirdanies

    2013-12-01

    Full Text Available Object recognition system using computer vision that is implemented on Remote Controlled Weapon Station (RCWS is discussed. This system will make it easier to identify and shoot targeted object automatically. Algorithm was created to recognize real time multiple objects using two methods i.e. Scale Invariant Feature Transform (SIFT and Speeded Up Robust Features (SURF combined with K-Nearest Neighbors (KNN and Random Sample Consensus (RANSAC for verification. The algorithm is designed to improve object detection to be more robust and to minimize the processing time required. Objects are registered on the system consisting of the armored personnel carrier, tanks, bus, sedan, big foot, and police jeep. In addition, object selection can use mouse to shoot another object that has not been registered on the system. Kinect™ is used to capture RGB images and to find the coordinates x, y, and z of the object. The programming language used is C with visual studio IDE 2010 and opencv libraries. Object recognition program is divided into three parts: 1 reading image from kinect™ and simulation results, 2 object recognition process, and 3 transfer of the object data to the ballistic computer. Communication between programs is performed using shared memory. The detected object data is sent to the ballistic computer via Local Area Network (LAN using winsock for ballistic calculation, and then the motor control system moves the direction of the weapon model to the desired object. The experimental results show that the SIFT method is more suitable because more accurate and faster than SURF with the average processing time to detect one object is 430.2 ms, two object is 618.4 ms, three objects is 682.4 ms, and four objects is 756.2 ms. Object recognition program is able to recognize multi-objects and the data of the identified object can be processed by the ballistic computer in realtime.

  6. Impacts of wave-induced circulation in the surf zone on wave setup

    Science.gov (United States)

    Guérin, Thomas; Bertin, Xavier; Coulombier, Thibault; de Bakker, Anouk

    2018-03-01

    Wave setup corresponds to the increase in mean water level along the coast associated with the breaking of short-waves and is of key importance for coastal dynamics, as it contributes to storm surges and the generation of undertows. Although overall well explained by the divergence of the momentum flux associated with short waves in the surf zone, several studies reported substantial underestimations along the coastline. This paper investigates the impacts of the wave-induced circulation that takes place in the surf zone on wave setup, based on the analysis of 3D modelling results. A 3D phase-averaged modelling system using a vortex force formalism is applied to hindcast an unpublished field experiment, carried out at a dissipative beach under moderate to very energetic wave conditions (Hm 0 = 6m at breaking and Tp = 22s). When using an adaptive wave breaking parameterisation based on the beach slope, model predictions for water levels, short waves and undertows improved by about 30%, with errors reducing to 0.10 m, 0.10 m and 0.09 m/s, respectively. The analysis of model results suggests a very limited impact of the vertical circulation on wave setup at this dissipative beach. When extending this analysis to idealized simulations for different beach slopes ranging from 0.01 to 0.05, it shows that the contribution of the vertical circulation (horizontal and vertical advection and vertical viscosity terms) becomes more and more relevant as the beach slope increases. In contrast, for a given beach slope, the wave height at the breaking point has a limited impact on the relative contribution of the vertical circulation on the wave setup. For a slope of 0.05, the contribution of the terms associated with the vertical circulation accounts for up to 17% (i.e. a 20% increase) of the total setup at the shoreline, which provides a new explanation for the underestimations reported in previously published studies.

  7. Sandstone uranium deposits: analogues for surf disposal in some sedimentary rocks

    International Nuclear Information System (INIS)

    Brookins, D.G.

    1987-01-01

    Sandstone uranium deposits are well suited as analogs for SURF. These deposits typically occur as tabular or lensoid masses of uraniferous sandstone, commonly where the argillaceous mineral and organic content is high. Primary minerals consist of pitchblende and/or coffinite, with possibly some urano-organic phases as well. The ore is usually associated with authigenic ferromagnesian clay minerals, such as chlorite and/or authigenic illite and/or mixed layer smectite-illite; and with pyrite ± jordisite ± seleniferrous species ± calcite. Organic matter is usually associated with the ore. The clay minerals in the ore zones are commonly vanadiferrous. The genesis of the sandstone uranium deposits is now fairly well understood and allows semi-quantitative estimates to be placed on behaviour of analog-elements for many constituents of SURF (or HLW). Prior to mineralization, oxidized species of U, V, Se, Mo, As are carried together as oxyanions; these species precipitate in a restricted range of Eh-pH when reducing conditions are met. Concomitant with removal of these species, due to formation of reduced, insoluble species, several other elements of interest are concentrated in the ore zones as well. Chalcophile elements, such as Cu, Co, Mn, Zn, Cd, Sb, and others are fixed in authigenic sulfide phases, and the alkalis Rb, K, and Cs are fixed in the authigenic illite and illitic mixed layer clays. The alkaline earth elements Sr and Ba are commonly fixed in sulfate-rich rock. The rare earth elements (REE) are incorporated into authigenic clay minerals or into oxy-hydroxide phases. (author)

  8. Probabilistic Modeling and Evaluation of Surf Zone Injury Occurrence along the Delaware Coast

    Science.gov (United States)

    Doelp, M.; Puleo, J. A.

    2017-12-01

    Beebe Healthcare in Lewes, DE collected along the DE coast surf zone injury (SZI) data for seven summer seasons from 2010 through 2016. Data include, but are not limited to, time of injury, gender, age, and activity. Over 2000 injuries were recorded over the seven year period, including 116 spinal injuries and three fatalities. These injuries are predominantly wave related incidents including wading (41%), bodysurfing (26%), and body-boarding (20%). Despite the large number of injuries, beach associated hazards do not receive the same level of awareness that rip currents receive. Injury population statistics revealed those between the ages of 11 and 15 years old suffered the greatest proportion of injuries (18.8%). Male water users were twice as likely to sustain injury as their female counterparts. Also, non-locals were roughly six times more likely to sustain injury than locals. In 2016, five or more injuries occurred for 18.5% of the days sampled, and no injuries occurred for 31.4% of the sample days. The episodic nature of injury occurrence and population statistics indicate the importance of environmental conditions and human behavior on surf zone injuries. Higher order statistics are necessary to effectively assess SZI cause and likelihood of occurrence on a particular day. A Bayesian network using Netica software (Norsys) was constructed to model SZI and predict changes in injury likelihood on an hourly basis. The network incorporates environmental data collected by weather stations, NDBC buoy #44009, USACE buoy at Bethany Beach, and by researcher personnel on the beach. The Bayesian model includes prior (e.g., historic) information to infer relationships between provided parameters. Sensitivity analysis determined the most influential variables to injury likelihood are population, water temperature, nearshore wave height, beach slope, and the day of the week. Forecasting during the 2017 summer season will test model ability to predict injury likelihood.

  9. Mapping bathymetry in an active surf zone with the WorldView2 multispectral satellite

    Science.gov (United States)

    Trimble, S. M.; Houser, C.; Brander, R.; Chirico, P.

    2015-12-01

    Rip currents are strong, narrow seaward flows of water that originate in the surf zones of many global beaches. They are related to hundreds of international drownings each year, but exact numbers are difficult to calculate due to logistical difficulties in obtaining accurate incident reports. Annual average rip current fatalities are estimated to be ~100, 53 and 21 in the United States (US), Costa Rica, and Australia respectively. Current warning systems (e.g. National Weather Service) do not account for fine resolution nearshore bathymetry because it is difficult to capture. The method shown here could provide frequent, high resolution maps of nearshore bathymetry at a scale required for improved rip prediction and warning. This study demonstrates a method for mapping bathymetry in the surf zone (20m deep and less), specifically within rip channels, because rips form at topographically low spots in the bathymetry as a result of feedback amongst waves, substrate, and antecedent bathymetry. The methods employ the Digital Globe WorldView2 (WV2) multispectral satellite and field measurements of depth to generate maps of the changing bathymetry at two embayed, rip-prone beaches: Playa Cocles, Puerto Viejo de Talamanca, Costa Rica, and Bondi Beach, Sydney, Australia. WV2 has a 1.1 day pass-over rate with 1.84m ground pixel resolution of 8 bands, including 'yellow' (585-625 nm) and 'coastal blue' (400-450 nm). The data is used to classify bottom type and to map depth to the return in multiple bands. The methodology is tested at each site for algorithm consistency between dates, and again for applicability between sites.

  10. Comparison of recreational health risks associated with surfing and swimming in dry weather and post-storm conditions at Southern California beaches using quantitative microbial risk assessment (QMRA).

    Science.gov (United States)

    Tseng, Linda Y; Jiang, Sunny C

    2012-05-01

    Southern California is an increasingly urbanized hotspot for surfing, thus it is of great interest to assess the human illness risks associated with this popular ocean recreational water sport from exposure to fecal bacteria contaminated coastal waters. Quantitative microbial risk assessments were applied to eight popular Southern California beaches using readily available enterococcus and fecal coliform data and dose-response models to compare health risks associated with surfing during dry weather and storm conditions. The results showed that the level of gastrointestinal illness risks from surfing post-storm events was elevated, with the probability of exceeding the US EPA health risk guideline up to 28% of the time. The surfing risk was also elevated in comparison with swimming at the same beach due to ingestion of greater volume of water. The study suggests that refinement of dose-response model, improving monitoring practice and better surfer behavior surveillance will improve the risk estimation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Recirculation effect of Chilean copper smelting dust with high impurities contents on the impurity distributions during smelting process; Efecto de la recirculacion de polvo de fundicion de cobre de Chile con altos contenidos de impurezas en la distribucion de impurezas durante el proceso de fusion

    Energy Technology Data Exchange (ETDEWEB)

    Montenegro, V.; Sano, H.; Fujisawa, T.

    2010-07-01

    Usually, dust generated during the copper smelting process by the Teniente Converter and the Flash Smelting Furnaces in Chile, contains high concentrations of copper, zinc, arsenic, antimony and other metals. In general, the dust is recirculated to the smelting process or it is directed to hydrometallurgical process for recovery and stabilization. However, in recent years the generation of dust has increased because of the degradation of the quality of the concentrate. In addition, the environmental regulations have become stricter. It is therefore desirable to understand the behavior of those elements, when the smelting process operates with recirculation of dust. In this study, the effect of dust recirculation to smelting process on the distribution among the matte, slag and gas phases was evaluated, as a function of matte grade, amount of recirculated dust, oxygen enrichment and temperature. It was found that the concentration in the matte of the impurities such as arsenic, antimony and bismuth, increased slightly with recirculation of dust. On the other hand, the concentration of lead and zinc depend of the direct recirculation of dust to the process. Additionally, it was found that high concentrations of arsenic and antimony in the dust may lead to the formation and precipitation of copper arsenates and other metals (speiss), which may generates important operational problems. (Author) 15 refs.

  12. Size-resolved dust and aerosol contaminants associated with copper and lead smelting emissions: Implications for emission management and human health

    Energy Technology Data Exchange (ETDEWEB)

    Csavina, Janae [Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Taylor, Mark P. [Environmental Science, Faculty of Science, Macquarie University, North Ryde, Sydney, NSW 2109 (Australia); Félix, Omar [Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Rine, Kyle P. [Department of Atmospheric Sciences, The University of Arizona, Tucson, AZ 85721 (United States); Eduardo Sáez, A., E-mail: esaez@email.arizona.edu [Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Betterton, Eric A., E-mail: betterton@atmo.arizona.edu [Department of Atmospheric Sciences, The University of Arizona, Tucson, AZ 85721 (United States)

    2014-09-15

    Mining operations, including crushing, grinding, smelting, refining, and tailings management, are a significant source of airborne metal and metalloid contaminants such as As, Pb and other potentially toxic elements. In this work, we show that size-resolved concentrations of As and Pb generally follow a bimodal distribution with the majority of contaminants in the fine size fraction (< 1 μm) around mining activities that include smelting operations at various sites in Australia and Arizona. This evidence suggests that contaminated fine particles (< 1 μm) are the result of vapor condensation and coagulation from smelting operations while coarse particles are most likely the result of windblown dust from contaminated mine tailings and fugitive emissions from crushing and grinding activities. These results on the size distribution of contaminants around mining operations are reported to demonstrate the ubiquitous nature of this phenomenon so that more effective emission management and practices that minimize health risks associated with metal extraction and processing can be developed. - Highlights: • Lead and copper smelting produce significant atmospheric concentrations of lead and arsenic. • Atmospheric lead and arsenic concentrations depend on particle size. • Lead isotopic analysis can be used to assess source of atmospheric contamination from smelters.

  13. Non-stationary recruitment dynamics of rainbow smelt: the influence of environmental variables and variation in size structure and length-at-maturation

    Science.gov (United States)

    Feiner, Zachary S.; Bunnell, David B.; Hook, Tomas O.; Madenjian, Charles P.; Warner, David M.; Collingsworth, Paris D.

    2015-01-01

    Fish stock-recruitment dynamics may be difficult to elucidate because of nonstationary relationships resulting from shifting environmental conditions and fluctuations in important vital rates such as individual growth or maturation. The Great Lakes have experienced environmental stressors that may have changed population demographics and stock-recruitment relationships while causing the declines of several prey fish species, including rainbow smelt (Osmerus mordax). We investigated changes in the size and maturation of rainbow smelt in Lake Michigan and Lake Huron and recruitment dynamics of the Lake Michigan stock over the past four decades. Mean lengths and length-at-maturation of rainbow smelt generally declined over time in both lakes. To evaluate recruitment, we used both a Ricker model and a Kalman filter-random walk (KF-RW) model which incorporated nonstationarity in stock productivity by allowing the productivity term to vary over time. The KF-RW model explained nearly four times more variation in recruitment than the Ricker model, indicating the productivity of the Lake Michigan stock has increased. By accounting for this nonstationarity, we were able identify significant variations in stock productivity, evaluate its importance to rainbow smelt recruitment, and speculate on potential environmental causes for the shift. Our results suggest that investigating mechanisms driving nonstationary shifts in stock-recruit relationships can provide valuable insights into temporal variation in fish population dynamics.

  14. Cestovní ruch a sociální sítě: Projekt CouchSurfing v Česku

    OpenAIRE

    Hásová, Adéla

    2012-01-01

    The master thesis focuses on the virtual social network sites which are concern to be exceptionally actual issue. Moreover the thesis deals with social networks in tourism. The number of various social networks about travelling is high. However, only the community of CouchSurfing (hospitality exchange network) was chosen for the research purposes of the thesis. The research included in the thesis focuses on CouchSurfing because is the greatest hospitality exchange site in these days. It inclu...

  15. Thermodynamics Calculation and Experimental Study on Separation of Bismuth from a Bismuth Glance Concentrate Through a Low-Temperature Molten Salt Smelting Process

    Science.gov (United States)

    Yang, Jian-Guang; He, De-Wen; Tang, Chao-Bo; Chen, Yong-Ming; Sun, Ya-Hui; Tang, Mo-Tang

    2011-08-01

    The main purpose of this study is to characterize and separate bismuth from a bismuth glance concentrate through a low-temperature, sulfur-fixing smelting process. This article reports on a study conducted on the optimization of process parameters, such as Na2CO3 and zinc oxide wt pct in charging, smelting temperature, smelting duration on the bismuth yield, resultant crude bismuth grade, and sulfur-fixing rate. A maximum bismuth recovery of 97.31 pct, crude bismuth grade of 96.93 pct, and 98.23 pct sulfur-fixing rate are obtained when a charge (containing 63.50 wt pct of Na2CO3 and 22.50 wt pct of bismuth glance, as well as 5 pct in excess of the stoichiometric requirement of zinc oxide dosage) is smelted at 1000 K (727 °C) for 150 minutes. This smelting operation is free from atmospheric pollution because zinc oxide is used as the sulfur-fixing agent, which can capture sulfur from bismuth sulfide and form the more thermodynamic-stable compound, zinc sulfide. The solid residue is subjected to a mineral dressing operation to obtain suspension, which is filtered to produce a cake, representing the solid particles of zinc sulfide. Based on the results of the chemical content analysis of the as-resultant zinc sulfide, more than 93 pct zinc sulfide can be recovered, and the recovered zinc sulfide grade can reach 60.20 pct. This material can be sold as zinc sulfide concentrate or roasted to be regenerated as zinc oxide.

  16. Deviation from Trajectory Detection in Vision based Robotic Navigation using SURF and Subsequent Restoration by Dynamic Auto Correction Algorithm

    Directory of Open Access Journals (Sweden)

    Ray Debraj

    2015-01-01

    Full Text Available Speeded Up Robust Feature (SURF is used to position a robot with respect to an environment and aid in vision-based robotic navigation. During the course of navigation irregularities in the terrain, especially in an outdoor environment may deviate a robot from the track. Another reason for deviation can be unequal speed of the left and right robot wheels. Hence it is essential to detect such deviations and perform corrective operations to bring the robot back to the track. In this paper we propose a novel algorithm that uses image matching using SURF to detect deviation of a robot from the trajectory and subsequent restoration by corrective operations. This algorithm is executed in parallel to positioning and navigation algorithms by distributing tasks among different CPU cores using Open Multi-Processing (OpenMP API.

  17. Rapid Microwave Digestion Procedures for the Elemental Analysis of Alloy and Slag Samples of Smelted Ocean Bed Polymetallic Nodules

    Directory of Open Access Journals (Sweden)

    Kumari Smita

    2013-01-01

    Full Text Available The use of microwave digester for digestion of alloy and slag samples of smelted ocean bed polymetallic nodules has permitted the complete digestion of samples, thereby replacing the tedious classical methods of digestion of samples. The digestion procedure includes two acid-closed digestions of samples in a microwave oven. Owing to the hazardous nature of perchloric acid, it was not used in developed digestion procedure. Digested sample solutions were analyzed for concentrations of various radicals and the effectiveness of the developed digestion methodology was tested using certified reference materials. It was found that the developed method is giving results comparable with that obtained from conventionally digested samples. In this digestion procedure, time required for digestion of samples was reduced to about 1 hour only from 8-9 hours of conventional digestion.

  18. Study of the ancient iron-smelting sites at Pantaki, Tsauni and Samaru-west, Nigeria, using neutron activation analysis

    International Nuclear Information System (INIS)

    Oladipupo, M.D.; OIadipo, M.O.A.; Mallam, S.P.; Akpa, T.C.

    2010-01-01

    Neutron activation analysis was used to obtain concentrations of some elements in samples of potsherds and furnaces obtained from Pantaki, Tsauni and Samaru-west ancient iron-smelting sites. Using WARD method, cluster analysis of the elements was carried out to establish the relationship between the archaeological samples in term of similarity in elemental concentrations. It was found that there is some level of similarity among the potsherd samples from the three sites. Also, most of furnace samples display some similarity. It was established that there was cultural linkage between the iron-smelters at the different sites. The similarity between the samples lead to a conclusion that pot makers and furnace makers could have existed, who obtained clays from common sources, made and sold the products to users in different communities.

  19. Preparation of Cementitious Material Using Smelting Slag and Tailings and the Solidification and Leaching of Pb2+

    Directory of Open Access Journals (Sweden)

    Dan Zhang

    2015-01-01

    Full Text Available The composite cementitious materials were prepared with lead-zinc tailings, lead-zinc smelting slag, and cement clinker. The effect of material ratio on the mechanical properties, the phase analysis, and microstructures were investigated. The effect of the pH and stripping time on the leaching amount of lead ion was discussed. The results show that the additive amount of the tailings should be minimized for the cementitious materials meeting the strength requirements, controlled within 10%. The leaching amount of cementitious materials remains low in a larger range of pH, which can effectively reduce the leaching of heavy metal lead. The leaching kinetics of lead ions in the three kinds of samples could be better described by the pseudo-second-model.

  20. Effect of Copper and Iron Ions on the Sulphidizing Flotation of Copper Oxide in Copper Smelting Slag

    Directory of Open Access Journals (Sweden)

    Qing-qing Pan

    2018-01-01

    Full Text Available The treatment of smelting slag has attracted much attention nowadays. This study investigates the influence of Na2S, CuSO4, and FeCl3 on sulphidizing flotation of copper oxide. The results show that a proper Cu2+ concentration can increase the sulphidizing effect of copper oxide, while Fe3+ inhibits the sulphidizing effect. Further analysis shows that Cu2+ ions can reduce the surface potential, increase the S2− adsorption, then generate more polysulfide, and therefore promote the sulphidizing flotation. However, Fe3+ ions would increase the surface potential, reduce the S2− adsorption, generate more sulfur element, and therefore inhibit the sulphidizing flotation.

  1. The Internet as a source of health information among Singaporeans: prevalence, patterns of health surfing and impact on health behaviour.

    Science.gov (United States)

    Siow, T R; Soh, I P; Sreedharan, S; Das De, S; Tan, P P; Seow, A; Lun, K C

    2003-11-01

    The Internet is an increasingly popular source of healthcare information. This study describes the prevalence of health surfers in Singapore and their health-surfing patterns. It also assesses their confidence in online health information and the impact the Internet has on health-seeking behaviour. A cross-sectional survey using a standardised questionnaire was carried out among residents aged 13 to 55 years in 1852 units in Bishan North. These units were selected by single-stage simple random cluster sampling method. The household response rate was 51% (n = 950) and the individual response rate was 69% (n = 1646). Responding and non-responding households were similar in terms of ethnicity and housing type. Of the responders, 62.9% surfed the Internet and 37.7% have surfed for health information. Health surfers tended to be younger (20 to 39 years) and have higher education status. Indians were also more likely than other ethnic groups to surf for health. Professional health-related sites comprised the majority (68%) of sites visited, and the most common search keywords concern chronic degenerative diseases, e.g. hypertension. The top preferred sources of health information were doctors (25.9%), the Internet (25.3%) and the traditional mass media (20.5%). Almost half (45.1%) considered online health information trustworthy if it was from a professional source or if the website displayed the source, while 10.6% trusted the information if it concurred with the doctors' advice. The vast majority (91.7%) had taken some action in response to the information. The Internet is being used as an accessible source of health information by a substantial proportion of the lay public. While this can facilitate greater partnership in healthcare, it underlines the need for doctors to be pro-active in the practice of evidence-based medicine, and for guidelines to enable patients to use this tool in a discerning manner.

  2. Ecophysiological and biochemical variation of the surf zone diatom asterionellopsis glacialis sensu lato from Santa Catarina, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Leonardo Rubi Rörig

    Full Text Available Abstract Patches formed by dense accumulations of diatoms in the surf zone (surf diatoms are common on sandy beaches with intermediate to dissipative morphodynamic states. Their appearances are correlated with environmental factors such as the passage of cold fronts when onshore winds increase beach hydrodynamics, resuspending epibenthic stocks and accumulating them through the inner surf zone. In Santa Catarina state, Southern Brazil, two beaches are known to have frequent occurrence of accumulations of the surf diatom Asterionellopsis glacialis sensu lato: Rincão Beach (28°50' S and Navegantes Beach (26°52' S. The high biomass of this alga and its central importance in the trophic structure of the coastal ecosystems suggest studies about its potential applications. In the present study, strains of A. glacialis were isolated, cultured under different conditions and evaluated for ecophysiological aspects: growth rate under different conditions, potential biological activities of exudates, biomass and lipid content, and fatty acid profile. A. glacialis cells in culture showed deformation, which were ameliorated by using agitation and silicon and phosphorus enriched culture media. Exudates of the strains showed no allelopathic effects, although previous studies have indicated activity. Lipid content showed variation depending on the strain and culture media. Values ranged from 9% to 13.6% by dry weight. In all strains saturated fatty acids and polyunsaturated fatty acids were identified. Some hypotheses were proposed to explain the variation of the lipid contents, fatty acid profiles and physiological features between strains of the same species. We believe that the fatty acids profile of this primary producer has important consequences in the sandy beach ecology.

  3. Decreased affinity for oxygen of cytochrome-c oxidase in Leigh syndrome caused by SURF1 mutations

    Czech Academy of Sciences Publication Activity Database

    Pecina, Petr; Gnaiger, E.; Zeman, J.; Pronicka, E.; Houštěk, Josef

    2004-01-01

    Roč. 287, č. 5 (2004), s. C1384-C1388 ISSN 0363-6143 R&D Projects: GA ČR(CZ) GA303/03/0749 Grant - others:CZ-AT(CZ) Kontakt-Aktion 2004/S; GA UK(CZ) 24/2004 Institutional research plan: CEZ:AV0Z5011922 Keywords : oxygen kinetics * mitochondrial disease * SURF1 Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 3.939, year: 2004

  4. Surf, sand, scrapes and stings: First aid incidents involving children at New Zealand beaches, 2007–2012.

    Science.gov (United States)

    Moran, Kevin; Webber, Jonathon

    2014-03-01

    Aims: In spite of the popularity of beaches for family recreation, little is known about childhood injuries sustained at beaches. It is the purpose of this study to analyse data from incidents necessitating first aid treatment from reports compiled by surf lifeguards on New Zealand beaches.Method: A retrospective analysis of first aid incidents involving children (safety via greater care giver awareness, the use of protective clothing and footwear, and child safety promotion via health professionals and safety organisations are discussed.

  5. Development and Evaluation of a Simple, Multifactorial Model Based on Landing Performance to Indicate Injury Risk in Surfing Athletes.

    Science.gov (United States)

    Lundgren, Lina E; Tran, Tai T; Nimphius, Sophia; Raymond, Ellen; Secomb, Josh L; Farley, Oliver R L; Newton, Robert U; Steele, Julie R; Sheppard, Jeremy M

    2015-11-01

    To develop and evaluate a multifactorial model based on landing performance to estimate injury risk for surfing athletes. Five measures were collected from 78 competitive surfing athletes and used to create a model to serve as a screening tool for landing tasks and potential injury risk. In the second part of the study, the model was evaluated using junior surfing athletes (n = 32) with a longitudinal follow-up of their injuries over 26 wk. Two models were compared based on the collected data, and magnitude-based inferences were applied to determine the likelihood of differences between injured and noninjured groups. The study resulted in a model based on 5 measures--ankle-dorsiflexion range of motion, isometric midthigh-pull lower-body strength, time to stabilization during a drop-and-stick (DS) landing, relative peak force during a DS landing, and frontal-plane DS-landing video analysis--for male and female professional surfers and male and female junior surfers. Evaluation of the model showed that a scaled probability score was more likely to detect injuries in junior surfing athletes and reported a correlation of r = .66, P = .001, with a model of equal variable importance. The injured (n = 7) surfers had a lower probability score (0.18 ± 0.16) than the noninjured group (n = 25, 0.36 ± 0.15), with 98% likelihood, Cohen d = 1.04. The proposed model seems sensitive and easy to implement and interpret. Further research is recommended to show full validity for potential adaptations for other sports.

  6. Bacterial community structure and diversity responses to the direct revegetation of an artisanal zinc smelting slag after 5 years.

    Science.gov (United States)

    Luo, Youfa; Wu, Yonggui; Wang, Hu; Xing, Rongrong; Zheng, Zhilin; Qiu, Jing; Yang, Lian

    2018-05-01

    This comparative field study examined the responses of bacterial community structure and diversity to the revegetation of zinc (Zn) smelting waste slag with eight plant species after 5 years. The microbial community structure of waste slag with and without vegetation was evaluated using high-throughput sequencing. The physiochemical properties of Zn smelting slag after revegetation with eight plant rhizospheres for 5 years were improved compared to those of bulk slag. Revegetation significantly increased the microbial community diversity in plant rhizospheres, and at the phylum level, Proteobacteria, Acidobacteria, and Bacteroidetes were notably more abundant in rhizosphere slags than those in bulk waste slag. Additionally, revegetation increased the relative abundance of plant growth-promoting rhizobacteria such as Flavobacterium, Streptomyces, and Arthrobacter as well as symbiotic N 2 fixers such as Bradyrhizobium. Three dominant native plant species (Arundo donax, Broussonetia papyrifera, and Robinia pseudoacacia) greatly increased the quality of the rhizosphere slags. Canonical correspondence analysis showed that the differences in bacterial community structure between the bulk and rhizosphere slags were explained by slag properties, i.e., pH, available copper (Cu) and lead (Pb), moisture, available nitrogen (N), phosphorus (P), and potassium (K), and organic matter (OM); however, available Zn and cadmium (Cd) contents were the slag parameters that best explained the differences between the rhizosphere communities of the eight plant species. The results suggested that revegetation plays an important role in enhancing bacterial community abundance and diversity in rhizosphere slags and that revegetation may also regulate microbiological properties and diversity mainly through changes in heavy metal bioavailability and physiochemical slag characteristics.

  7. A Comparison of Aerobic Fitness Testing on a Swim Bench and Treadmill in a Recreational Surfing Cohort: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Hamzeh Khundaqji

    2018-06-01

    Full Text Available The intermittent manner of surfing accentuates the importance of both the aerobic and anaerobic energy systems. Currently, the optimal method of assessing surfing-specific aerobic fitness is using a swim bench (SWB ergometer; however, their limited availability presents a barrier to surfers wanting to know their maximal aerobic power (VO2peak. As a result, the aims of this pilot study were to determine the VO2peak of recreational surfers using a new commercial SWB ergometer and to propose and examine the feasibility of a regression model to predict SWB ergometer VO2peak values. A total of nine recreational surfers were assessed where body measurements were conducted followed by maximal aerobic capacity testing (swim bench and treadmill to profile the cohort. Findings demonstrated that VO2peak values were significantly greater (p < 0.001 on the treadmill compared to the SWB ergometer (M = 66.01 ± 8.23 vs. 37.41 ± 8.73 mL/kg/min. Peak heart rate was also significantly greater on the treadmill compared to the SWB ergometer. Multiple regression analysis was used to produce a model which predicted SWB VO2peak values with an R2 value of 0.863 and an adjusted R2 value of 0.726. The physiological profiling of the recreational cohort coupled with a surfer’s predicted SWB VO2peak value will allow for identification of surfing-specific aerobic fitness levels and evidence-based training recommendations.

  8. FEATURE RECOGNITION BERBASIS CORNER DETECTION DENGAN METODE FAST, SURF DAN FLANN TREE UNTUK IDENTIFIKASI LOGO PADA AUGMENTED REALITY MOBILE SYSTEM

    Directory of Open Access Journals (Sweden)

    Rastri Prathivi

    2014-01-01

    Full Text Available Logo is a graphical symbol that is the identity of an organization, institution, or company. Logo is generally used to introduce to the public the existence of an organization, institution, or company. Through the existence of an agency logo can be seen by the public. Feature recognition is one of the processes that exist within an augmented reality system. One of uses augmented reality is able to recognize the identity of the logo through a camera.The first step to make a process of feature recognition is through the corner detection. Incorporation of several method such as FAST, SURF, and FLANN TREE for the feature detection process based corner detection feature matching up process, will have the better ability to detect the presence of a logo. Additionally when running the feature extraction process there are several issues that arise as scale invariant feature and rotation invariant feature. In this study the research object in the form of logo to the priority to make the process of feature recognition. FAST, SURF, and FLANN TREE method will detection logo with scale invariant feature and rotation invariant feature conditions. Obtained from this study will demonstration the accuracy from FAST, SURF, and FLANN TREE methods to solve the scale invariant and rotation invariant feature problems.

  9. SURF - SUrvey of Risk Factor management: first report of an international audit.

    Science.gov (United States)

    Cooney, Mt; Reiner, Z; Sheu, W; Ryden, L; Sutter, J de; De Bacquer, D; DeBacker, G; Mithal, A; Chung, N; Lim, Yt; Dudina, A; Reynolds, A; Dunney, K; Graham, I

    2014-07-01

    Despite the fact that subjects with established coronary heart disease (CHD) are at high risk of further events and deserve meticulous secondary prevention, current audits such as EUROASPIRE show poor control of major risk factors. Ongoing monitoring is required. We present a new risk factor audit system, SURF (Survey of Risk Factor management), that can be conducted much more quickly and easily than existing audit systems and has the potential to allow hospitals of all sizes to participate in a unified international audit system that will complement EUROASPIRE. Initial experience indicates that SURF is truly simple to undertake in an international setting, and this is illustrated with the results of a substantive pilot project conducted in Europe and Asia. The data collection system was designed to allow rapid and easy data collection as part of routine clinic work. Consecutive patients (aged 18 and over) with established CHD attending outpatient cardiology clinics were included. Information on demographics, previous coronary medical history, smoking history, history of hypertension, dyslipidaemia or diabetes, physical activity, attendance at cardiac rehabilitation, cardiac medications, lipid and glucose levels (and HbA1c in diabetics) if available within the last year, blood pressure, heart rate, body mass index, and waist circumference were collected using a one-page data collection sheet. Years spent in full time education was added as an additional question during the pilot phase. Three European countries - Ireland (n = 251), Belgium (n = 122), and Croatia (n = 124) - and four Asian countries - Singapore (n = 142), Taiwan (n = 334), India (n = 97), and Korea (n = 45) - were included in the pilot study. The results of initial field testing were confirmed in that it proved possible to collect data within 60-90 seconds per subject. There was poor control of several risk factors including high levels of physical inactivity (41

  10. Ablation of the mitochondrial complex IV assembly protein Surf1 leads to increased expression of the UPRMT and increased resistance to oxidative stress in primary cultures of fibroblasts

    Directory of Open Access Journals (Sweden)

    Gavin Pharaoh

    2016-08-01

    Full Text Available Mice deficient in the electron transport chain (ETC complex IV assembly protein SURF1 have reduced assembly and activity of cytochrome c oxidase that is associated with an upregulation of components of the mitochondrial unfolded protein response (UPRMT and increased mitochondrial number. We hypothesized that the upregulation of proteins associated with the UPRMT in response to reduced cytochrome c oxidase activity in Surf1−/− mice might contribute to increased stress resistance. To test this hypothesis we asked whether primary cultures of fibroblasts from Surf1−/− mice exhibit enhanced resistance to stressors compared to wild-type fibroblasts. Here we show that primary dermal fibroblasts isolated from Surf1−/− mice have increased expression of UPRMT components ClpP and Hsp60, and increased expression of Lon protease. Fibroblasts from Surf1−/− mice are significantly more resistant to cell death caused by oxidative stress induced by paraquat or tert-Butyl hydroperoxide compared to cells from wild-type mice. In contrast, Surf1−/− fibroblasts show no difference in sensitivity to hydrogen peroxide stress. The enhanced cell survival in response to paraquat or tert-Butyl hydroperoxide in Surf1−/− fibroblasts compared to wild-type fibroblasts is associated with induced expression of Lon, ClpP, and Hsp60, increased maximal respiration, and increased reserve capacity as measured using the Seahorse Extracellular Flux Analyzer. Overall these data support a protective role for the activation of the UPRMT in cell survival.

  11. A high throughput 2 m normal incidence monochromator for SURF-II

    International Nuclear Information System (INIS)

    Ederer, D.L.; Cole, B.E.; West, J.B.

    1980-01-01

    The high intrinsic brightness of the circulating electron beam at SURF-II is used as the entrance slit for a two-meter normal incidence monochromator. A typical beam size for the electron beam is 100 μm high by 2 mm wide yielding an obserbed resolution of 0.4 Angstroem with a 200 μm exit slit and a 2400 lines/mm grating. The instrument accepts a beam with a 65 mrad horizontal divergence and a 10 mrad vertical divergence. A plane pre-mirror used near normal incidence reflects the incoming radiation onto the 2 m grating; this combination provides a horizontal exit beam, and enables the experiment to be located three meters from the orbit tangent point. With magnesium fluoride coated aluminium optics a flux of 2 x 10'' photon/s x Angstroem at 1200 Angstroem is observed with a 10 mA circulating current. A flux of 5 x 10 10 photon/s x Angstroem at 600 Angstroem is obserbed with an osmium coated grating and a 10 mA circulating current. Sample spectra of the angle-resolved photoelectron spectrum of CO are presented. (orig.)

  12. Impacts of beach wrack removal via grooming on surf zone water quality.

    Science.gov (United States)

    Russell, Todd L; Sassoubre, Lauren M; Zhou, Christina; French-Owen, Darien; Hassaballah, Abdulrahman; Boehm, Alexandria B

    2014-02-18

    Fecal indicator bacteria (FIB) are used to assess the microbial water quality of recreational waters. Increasingly, nonfecal sources of FIB have been implicated as causes of poor microbial water quality in the coastal environment. These sources are challenging to quantify and difficult to remediate. The present study investigates one nonfecal FIB source, beach wrack (decaying aquatic plants), and its impacts on water quality along the Central California coast. The prevalence of FIB on wrack was studied using a multibeach survey, collecting wrack throughout Central California. The impacts of beach grooming, to remove wrack, were investigated at Cowell Beach in Santa Cruz, California using a long-term survey (two summers, one with and one without grooming) and a 48 h survey during the first ever intensive grooming event. FIB were prevalent on wrack but highly variable spatially and temporally along the nine beaches sampled in Central California. Beach grooming was generally associated with either no change or a slight increase in coastal FIB concentrations and increases in surf zone turbidity and silicate, phosphate, and dissolved inorganic nitrogen concentrations. The findings suggest that beach grooming for wrack removal is not justified as a microbial pollution remediation strategy.

  13. Surf Zone Hydrodynamics and its Utilization in Biotechnical Stabilization of Water Reservoir Banks

    Directory of Open Access Journals (Sweden)

    Petr Pelikán

    2014-01-01

    Full Text Available The water reservoir banks are eroded mainly by two factors. The first one is wave action (i.e. wave abrasion affecting the bank in direction from the reservoir. The second one is the influence of water flowing downward over the bank surface in direction from land into the reservoir (e.g. rainfall. The determination of regular altitudinal emplacement of proper designed particular biotechnical stabilization elements is the most important factor on which the right functionality of whole construction depends. Surf zone hydrodynamics solves the wave and water level changes inside the region extending from the wave breaking point to the limit of wave up-rush. The paper is focused on the utilization of piece of knowledge from a part of sea coast hydrodynamics and new approach in its application in the conditions of inland water bodies when designing the biotechnical stabilization elements along the shorelines. The “reinforced grass carpets” as a type of biotechnical method of bank stabilization are presented in the paper; whether the growth of grass root system is dependent on presence or absence of geomats in the soil structure and proceeding of their establishment on the shorelines.

  14. Hybrid Video Stabilization for Mobile Vehicle Detection on SURF in Aerial Surveillance

    Directory of Open Access Journals (Sweden)

    Gao Chunxian

    2015-01-01

    Full Text Available Detection of moving vehicles in aerial video sequences is of great importance with many promising applications in surveillance, intelligence transportation, or public service applications such as emergency evacuation and policy security. However, vehicle detection is a challenging task due to global camera motion, low resolution of vehicles, and low contrast between vehicles and background. In this paper, we present a hybrid method to efficiently detect moving vehicle in aerial videos. Firstly, local feature extraction and matching were performed to estimate the global motion. It was demonstrated that the Speeded Up Robust Feature (SURF key points were more suitable for the stabilization task. Then, a list of dynamic pixels was obtained and grouped for different moving vehicles by comparing the different optical flow normal. To enhance the precision of detection, some preprocessing methods were applied to the surveillance system, such as road extraction and other features. A quantitative evaluation on real video sequences indicated that the proposed method improved the detection performance significantly.

  15. Genetic surfing, not allopatric divergence, explains spatial sorting of mitochondrial haplotypes in venomous coralsnakes.

    Science.gov (United States)

    Streicher, Jeffrey W; McEntee, Jay P; Drzich, Laura C; Card, Daren C; Schield, Drew R; Smart, Utpal; Parkinson, Christopher L; Jezkova, Tereza; Smith, Eric N; Castoe, Todd A

    2016-07-01

    Strong spatial sorting of genetic variation in contiguous populations is often explained by local adaptation or secondary contact following allopatric divergence. A third explanation, spatial sorting by stochastic effects of range expansion, has been considered less often though theoretical models suggest it should be widespread, if ephemeral. In a study designed to delimit species within a clade of venomous coralsnakes, we identified an unusual pattern within the Texas coral snake (Micrurus tener): strong spatial sorting of divergent mitochondrial (mtDNA) lineages over a portion of its range, but weak sorting of these lineages elsewhere. We tested three alternative hypotheses to explain this pattern-local adaptation, secondary contact following allopatric divergence, and range expansion. Collectively, near panmixia of nuclear DNA, the signal of range expansion associated sampling drift, expansion origins in the Gulf Coast of Mexico, and species distribution modeling suggest that the spatial sorting of divergent mtDNA lineages within M. tener has resulted from genetic surfing of standing mtDNA variation-not local adaptation or allopatric divergence. Our findings highlight the potential for the stochastic effects of recent range expansion to mislead estimations of population divergence made from mtDNA, which may be exacerbated in systems with low vagility, ancestral mtDNA polymorphism, and male-biased dispersal. © 2016 The Author(s).

  16. Electron surfing acceleration by the electron two-stream instability in a weak magnetic field

    International Nuclear Information System (INIS)

    Dieckmann, M E; Shukla, P K

    2006-01-01

    The thermalization of relativistically flowing colliding plasmas is not well understood. The transition layer, in which both plasmas interact and thermalize, is wide and highly structured and the instabilities in this layer may yield non-thermal particle distributions and shock-less energy dissipation. The objective in this work is to explore the ability of an electron two-stream instability for thermalizing a plasma beam that moves at the mildly relativistic speed 0.3c through weakly magnetized plasma and to identify the resulting particle distributions. It is demonstrated here with particle-in-cell simulations that the electron two-stream instability leads to waves that propagate within a wide angular range relative to the flow velocity. The waves are thus not planar, as required for efficient electron surfing acceleration (ESA). The short lifetime of the waves implies, however, only weak modifications of the ESA by the oblique modes, since the waves are sufficiently homogeneous. The ion (proton) beams are not modulated, which would be required to extract some of their energy. The instability can thus heat the electrons significantly, but it fails to accelerate them to relativistic energies and it cannot form a shock layer by thermalizing the protons, at least not for the system and the resolved timescales considered here

  17. The Prevalence of Rough Sleeping and Sofa Surfing Amongst Young People in the UK

    Directory of Open Access Journals (Sweden)

    Anna Clarke

    2016-10-01

    Full Text Available Whilst data on statutory homelessness is well recorded in the UK, there is a lack of data on informal homelessness (such as ‘sofa surfing’ and rough sleeping, other than that which relies on partial information and street counts. This paper presents findings from a recent online survey of young people and helps to fill this gap. It found that rates of sofa surfing and rough sleeping among young people were much higher than previously thought. Twenty-six percent of young people (aged 16–25 had slept rough at some point in their life and 35 percent had ‘sofa surfed’ (stayed with friends or family on their floor or sofa because they had nowhere else to go. The paper explores the implications of this for how we conceptualise homelessness. It suggests that homelessness may often be neither cause nor consequence of wider forms of exclusion, but that we may need to explore further the factors that enable some people to move swiftly out of homelessness more easily than others.

  18. Electron surfing acceleration by the electron two-stream instability in a weak magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Dieckmann, M E; Shukla, P K [Institut fuer Theoretische Physik IV, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

    2006-10-15

    The thermalization of relativistically flowing colliding plasmas is not well understood. The transition layer, in which both plasmas interact and thermalize, is wide and highly structured and the instabilities in this layer may yield non-thermal particle distributions and shock-less energy dissipation. The objective in this work is to explore the ability of an electron two-stream instability for thermalizing a plasma beam that moves at the mildly relativistic speed 0.3c through weakly magnetized plasma and to identify the resulting particle distributions. It is demonstrated here with particle-in-cell simulations that the electron two-stream instability leads to waves that propagate within a wide angular range relative to the flow velocity. The waves are thus not planar, as required for efficient electron surfing acceleration (ESA). The short lifetime of the waves implies, however, only weak modifications of the ESA by the oblique modes, since the waves are sufficiently homogeneous. The ion (proton) beams are not modulated, which would be required to extract some of their energy. The instability can thus heat the electrons significantly, but it fails to accelerate them to relativistic energies and it cannot form a shock layer by thermalizing the protons, at least not for the system and the resolved timescales considered here.

  19. A unified spectral parameterization for wave breaking: From the deep ocean to the surf zone

    Science.gov (United States)

    Filipot, J.-F.; Ardhuin, F.

    2012-11-01

    A new wave-breaking dissipation parameterization designed for phase-averaged spectral wave models is presented. It combines wave breaking basic physical quantities, namely, the breaking probability and the dissipation rate per unit area. The energy lost by waves is first explicitly calculated in physical space before being distributed over the relevant spectral components. The transition from deep to shallow water is made possible by using a dissipation rate per unit area of breaking waves that varies with the wave height, wavelength and water depth. This parameterization is implemented in the WAVEWATCH III modeling framework, which is applied to a wide range of conditions and scales, from the global ocean to the beach scale. Wave height, peak and mean periods, and spectral data are validated using in situ and remote sensing data. Model errors are comparable to those of other specialized deep or shallow water parameterizations. This work shows that it is possible to have a seamless parameterization from the deep ocean to the surf zone.

  20. Research on the Characteristics and Mechanism of the Cumulative Release of Antimony from an Antimony Smelting Slag Stacking Area under Rainfall Leaching

    Science.gov (United States)

    Zhou, Yingying; Deng, Renjian

    2017-01-01

    We aimed to study the characteristics and the mechanism of the cumulative release of antimony at an antimony smelting slag stacking area in southern China. A series of dynamic and static leaching experiments to simulate the effects of rainfall were carried out. The results showed that the release of antimony from smelting slag increased with a decrease in the solid-liquid ratio, and the maximum accumulated release was found to be 42.13 mg Sb/kg waste and 34.26 mg Sb/kg waste with a solid/liquid ratio of 1 : 20; the maximum amount of antimony was released within 149–420 μm size fraction with 7.09 mg/L of the cumulative leaching. Also, the antimony release was the greatest and most rapid at pH 7.0 with the minimum release found at pH 4.0. With an increase in rainfall duration, the antimony release increased. The influence of variation in rainfall intensity on the release of antimony from smelting slag was small. PMID:28804669

  1. Transplantation of epiphytic bioaccumulators (Tillandsia capillaris) for high spatial resolution biomonitoring of trace elements and point sources deconvolution in a complex mining/smelting urban context

    Science.gov (United States)

    Goix, Sylvaine; Resongles, Eléonore; Point, David; Oliva, Priscia; Duprey, Jean Louis; de la Galvez, Erika; Ugarte, Lincy; Huayta, Carlos; Prunier, Jonathan; Zouiten, Cyril; Gardon, Jacques

    2013-12-01

    Monitoring atmospheric trace elements (TE) levels and tracing their source origin is essential for exposure assessment and human health studies. Epiphytic Tillandsia capillaris plants were used as bioaccumulator of TE in a complex polymetallic mining/smelting urban context (Oruro, Bolivia). Specimens collected from a pristine reference site were transplanted at a high spatial resolution (˜1 sample/km2) throughout the urban area. About twenty-seven elements were measured after a 4-month exposure, also providing new information values for reference material BCR482. Statistical power analysis for this biomonitoring mapping approach against classical aerosols surveys performed on the same site showed the better aptitude of T. Capillaris to detect geographical trend, and to deconvolute multiple contamination sources using geostatistical principal component analysis. Transplanted specimens in the vicinity of the mining and smelting areas were characterized by extreme TE accumulation (Sn > Ag > Sb > Pb > Cd > As > W > Cu > Zn). Three contamination sources were identified: mining (Ag, Pb, Sb), smelting (As, Sn) and road traffic (Zn) emissions, confirming results of previous aerosol survey.

  2. Geochemical and Pb isotopic evidence for sources and dispersal of metal contamination in stream sediments from the mining and smelting district of Pribram, Czech Republic

    International Nuclear Information System (INIS)

    Ettler, Vojtech; Mihaljevic, Martin; Sebek, Ondrej; Molek, Michael; Grygar, Tomas; Zeman, Josef

    2006-01-01

    Stream sediments from the mining and smelting district of Pribram, Czech Republic, were studied to determine the degree, sources and dispersal of metal contamination using a combination of bulk metal and mineralogical determinations, sequential extractions and Pb isotopic analyses. The highest metal concentrations were found 3-4 km downstream from the main polymetallic mining site (9800 mg Pb kg -1 , 26 039 mg Zn kg -1 , 316.4 mg Cd kg -1 , 256.9 mg Cu kg -1 ). The calculated enrichment factors (EFs) confirmed the extreme degree of contamination by Pb, Zn and Cd (EF > 40). Lead, Zn and Cd are bound mainly to Fe oxides and hydroxides. In the most contaminated samples Pb is also present as Pb carbonates and litharge (PbO). Lead isotopic analysis indicates that the predominant source of stream sediment contamination is historic Pb-Ag mining and primary Pb smelting ( 206 Pb/ 207 Pb = 1.16), while the role of secondary smelting (car battery processing) is negligible. - Pb isotopes properly complete traditional investigations of metal sources and dispersal in contaminated stream sediments

  3. Scale invariant SURF detector and automatic clustering segmentation for infrared small targets detection

    Science.gov (United States)

    Zhang, Haiying; Bai, Jiaojiao; Li, Zhengjie; Liu, Yan; Liu, Kunhong

    2017-06-01

    The detection and discrimination of infrared small dim targets is a challenge in automatic target recognition (ATR), because there is no salient information of size, shape and texture. Many researchers focus on mining more discriminative information of targets in temporal-spatial. However, such information may not be available with the change of imaging environments, and the targets size and intensity keep changing in different imaging distance. So in this paper, we propose a novel research scheme using density-based clustering and backtracking strategy. In this scheme, the speeded up robust feature (SURF) detector is applied to capture candidate targets in single frame at first. And then, these points are mapped into one frame, so that target traces form a local aggregation pattern. In order to isolate the targets from noises, a newly proposed density-based clustering algorithm, fast search and find of density peak (FSFDP for short), is employed to cluster targets by the spatial intensive distribution. Two important factors of the algorithm, percent and γ , are exploited fully to determine the clustering scale automatically, so as to extract the trace with highest clutter suppression ratio. And at the final step, a backtracking algorithm is designed to detect and discriminate target trace as well as to eliminate clutter. The consistence and continuity of the short-time target trajectory in temporal-spatial is incorporated into the bounding function to speed up the pruning. Compared with several state-of-arts methods, our algorithm is more effective for the dim targets with lower signal-to clutter ratio (SCR). Furthermore, it avoids constructing the candidate target trajectory searching space, so its time complexity is limited to a polynomial level. The extensive experimental results show that it has superior performance in probability of detection (Pd) and false alarm suppressing rate aiming at variety of complex backgrounds.

  4. Frequent Surfing on Social Health Networks is Associated With Increased Knowledge and Patient Health Activation.

    Science.gov (United States)

    Grosberg, Dafna; Grinvald, Haya; Reuveni, Haim; Magnezi, Racheli

    2016-08-10

    The advent of the Internet has driven a technological revolution that has changed our lives. As part of this phenomenon, social networks have attained a prominent role in health care. A variety of medical services is provided over the Internet, including home monitoring, interactive communications between the patient and service providers, and social support, among others. This study emphasizes some of the practical implications of Web-based health social networks for patients and for health care systems. The objective of this study was to assess how participation in a social network among individuals with a chronic condition contributed to patient activation, based on the Patient Activation Measure (PAM). A prospective, cross-sectional survey with a retrospective component was conducted. Data were collected from Camoni, a Hebrew-language Web-based social health network, participants in the diabetes mellitus, pain, hypertension, and depression/anxiety forums, during November 2012 to 2013. Experienced users (enrolled at least 6 months) and newly enrolled received similar versions of the same questionnaire including sociodemographics and PAM. Among 686 participants, 154 of 337 experienced and 123 of 349 newly enrolled completed the questionnaire. Positive correlations (Psocial relationships, and chronic disease knowledge. Men surfed longer than women (χ²3=10.104, Psocial health network use were correlated with increased knowledge about a chronic disease. Experienced surfers had higher PAM than newly enrolled, suggesting that continued site use may contribute to increased activation. Web-based social health networks offer an opportunity to expand patient knowledge and increase involvement in personal health, thereby increasing patient activation. Further studies are needed to examine these changes on other aspects of chronic illnesses such as quality of life and costs.

  5. Isolation of a library of aromadendranes from Landolphia dulcis and its characterization using the VolSurf approach

    DEFF Research Database (Denmark)

    Staerk, Dan; Skole, Brian; Jørgensen, Flemming Steen

    2004-01-01

    -energy structures obtained with the MMFF force field. VolSurf descriptors were calculated from the GRID maps and subsequently analyzed by multivariate statistics. The analysis disclosed the presence of a common motif for possible interactions of the aromadendranes with a putative target receptor. At the same time...... established by means of NMR methods including COSY, NOESY, HSQC, and HMBC experiments, supported by HRMS and optical rotation data. Virtual characterization of the aromadendrane library (1-9) was performed using chemoinformatics tools. 3D molecular fields were calculated with the GRID program using low...

  6. Tissue-specific cytochrome c oxidase assembly defects due to mutations in SCO2 and SURF1

    Czech Academy of Sciences Publication Activity Database

    Stibůrek, L.; Veselá, K.; Hansíková, H.; Pecina, Petr; Tesařová, M.; Černá, L.; Houštěk, Josef; Zeman, J.

    2005-01-01

    Roč. 392, č. 3 (2005), s. 625-632 ISSN 0264-6021 R&D Projects: GA ČR(CZ) GA303/03/0749; GA MŠk(CZ) 1M0520; GA ČR(CZ) GP303/03/D132 Grant - others:GA UK(CZ) 17/2004/C; Priority 1(XE) LSHMCT-2004-503116 Institutional research plan: CEZ:AV0Z50110509 Keywords : assembly pathway * cytochrome c oxidase * SURF1 Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 4.224, year: 2005

  7. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Mid-Atlantic). SURF CLAM

    Science.gov (United States)

    1983-10-01

    ter across the vitelline membrane; the Male and female surf clams are identi- innqr germinal vesicle averages 0.79 cal in external appearance, and...Jones et al. ) (1978) reported age-size relationships In laboratcry experiments con- using cut and polished shells (Table ducted •t 21.7 0 C (71 0 F...and Long Island’s south period (4-6 weeks), due to a persist - shore, out. to a depth of 75 m (246 ent southerly flow of air;. and ft), because of the

  8. Technogenic magnetic particles in soils as evidence of historical mining and smelting activity: A case of the Brynica River Valley, Poland

    Energy Technology Data Exchange (ETDEWEB)

    Magiera, Tadeusz, E-mail: tadeusz.magiera@ipis.zabrze.pl [Institute of Environmental Engineering, Polish Academy of Sciences, Skłodowskiej-Curie 34, Zabrze (Poland); Mendakiewicz, Maria; Szuszkiewicz, Marcin [Institute of Environmental Engineering, Polish Academy of Sciences, Skłodowskiej-Curie 34, Zabrze (Poland); Jabłońska, Mariola [Department of Geochemistry, Mineralogy and Petrology, Faculty of Earth Sciences, University of Silesia, Sosnowiec (Poland); Chróst, Leszek [Laboratory for Ecological Research, Ekopomiar, Gliwice (Poland)

    2016-10-01

    In the area of Brynica River basin (Upper Silesia, southern Poland) the exploitation and smelting of iron, silver and lead ores was historically documented since early Middle Ages. First investigations showed that metallurgy industry had a large impact from 9th century (AD) until the Second World War. The aim of the study was to use magnetic prospection to detect traces of past mining and ore smelting in Brynica River Valley located in Upper Silesia (southern Poland). The field screening was performed by measurement magnetic susceptibility (κ) on surface and in vertical profiles and was supported locally by gradiometric measurements. Vertical distribution of magnetic susceptibility values was closely associated with the type of soil use. Historical technogenic magnetic particles resulting from exploitation, processing, and smelting of iron, silver, and lead ores were accumulated in the soil layer at the depth 10 to 25 cm. They were represented by sharp-edged particles of slag, coke, as well as various mineralogical forms of iron minerals and aggregates composed of carbon particles, aluminosilicate glass, and single particles of metallic iron. The additional geochemical study in adjacent peat bog supported by radiocarbon dating was also performed. The application of integrated geochemical-magnetic methods to reconstruct the historical accumulation of pollutants in the studied peat bog was effective. The magnetic peak, which was pointed out by magnetic analyses, is consistent with the presence of charcoal and pollution from heavy metals, such as Ag, Cd, Cu, Fe, Pb, or Sn. The results of this work will be helpful for the further study of human's impact on the environment related to the historical and even pre-historical ore exploitation and smelting and also used for better targeting the archeological excavations on such areas. - Highlights: • Due to ferrimagnetic properties of historical slags magnetic prospection is an efficient tool for they localization.

  9. [Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province and evaluation of its ecological risk].

    Science.gov (United States)

    Jin, Shu-Lan; Huang, Yi-Zong; Wang, Fei; Xu, Feng; Wang, Xiao-Ling; Gao, Zhu; Hu, Ying; Qiao Min; Li, Jin; Xiang, Meng

    2015-03-01

    Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province was studied. The results showed that copper mining and smelting could increase the content of rare earth elements in soils and crops. Rare earth elements content in farmland soils of the surrounding Yinshan Lead Zinc Copper Mine and Guixi Smelting Plant varied from 112.42 to 397.02 mg x kg(-1) and 48.81 to 250.06 mg x kg(-1), and the average content was 254.84 mg x kg(-1) and 144.21 mg x kg(-1), respectively. The average contents of rare earth elements in soils in these two areas were 1.21 times and 0.68 times of the background value in Jiangxi province, 1.36 times and 0.77 times of the domestic background value, 3.59 times and 2.03 times of the control samples, respectively. Rare earth elements content in 10 crops of the surrounding Guixi Smelting Plant varied from 0.35 to 2.87 mg x kg(-1). The contents of rare earth elements in the leaves of crops were higher than those in stem and root. The contents of rare earth elements in Tomato, lettuce leaves and radish leaves were respectively 2.87 mg x kg(-1), 1.58 mg x kg(-1) and 0.80 mg x kg(-1), which were well above the hygienic standard limit of rare earth elements in vegetables and fruits (0.70 mg x kg(-1)). According to the health risk assessment method recommended by America Environmental Protection Bureau (USEPA), we found that the residents' lifelong average daily intake of rare earth elements was 17.72 mg x (kg x d)(-1), lower than the critical value of rare earth elements damage to human health. The results suggested that people must pay attention to the impact of rare earth elements on the surrounding environment when they mine and smelt copper ore in Jiangxi.

  10. Technogenic magnetic particles in soils as evidence of historical mining and smelting activity: A case of the Brynica River Valley, Poland

    International Nuclear Information System (INIS)

    Magiera, Tadeusz; Mendakiewicz, Maria; Szuszkiewicz, Marcin; Jabłońska, Mariola; Chróst, Leszek

    2016-01-01

    In the area of Brynica River basin (Upper Silesia, southern Poland) the exploitation and smelting of iron, silver and lead ores was historically documented since early Middle Ages. First investigations showed that metallurgy industry had a large impact from 9th century (AD) until the Second World War. The aim of the study was to use magnetic prospection to detect traces of past mining and ore smelting in Brynica River Valley located in Upper Silesia (southern Poland). The field screening was performed by measurement magnetic susceptibility (κ) on surface and in vertical profiles and was supported locally by gradiometric measurements. Vertical distribution of magnetic susceptibility values was closely associated with the type of soil use. Historical technogenic magnetic particles resulting from exploitation, processing, and smelting of iron, silver, and lead ores were accumulated in the soil layer at the depth 10 to 25 cm. They were represented by sharp-edged particles of slag, coke, as well as various mineralogical forms of iron minerals and aggregates composed of carbon particles, aluminosilicate glass, and single particles of metallic iron. The additional geochemical study in adjacent peat bog supported by radiocarbon dating was also performed. The application of integrated geochemical-magnetic methods to reconstruct the historical accumulation of pollutants in the studied peat bog was effective. The magnetic peak, which was pointed out by magnetic analyses, is consistent with the presence of charcoal and pollution from heavy metals, such as Ag, Cd, Cu, Fe, Pb, or Sn. The results of this work will be helpful for the further study of human's impact on the environment related to the historical and even pre-historical ore exploitation and smelting and also used for better targeting the archeological excavations on such areas. - Highlights: • Due to ferrimagnetic properties of historical slags magnetic prospection is an efficient tool for they localization.

  11. Cd, Pb, and Zn mobility and (bio)availability in contaminated soils from a former smelting site amended with biochar.

    Science.gov (United States)

    Lomaglio, Tonia; Hattab-Hambli, Nour; Miard, Florie; Lebrun, Manhattan; Nandillon, Romain; Trupiano, Dalila; Scippa, Gabriella Stefania; Gauthier, Arnaud; Motelica-Heino, Mikael; Bourgerie, Sylvain; Morabito, Domenico

    2017-07-20

    Biochar is a potential candidate for the remediation of metal(loid)-contaminated soils. However, the mechanisms of contaminant-biochar retention and release depend on the amount of soil contaminants and physicochemical characteristics, as well as the durability of the biochar contaminant complex, which may be related to the pyrolysis process parameters. The objective of the present study was to evaluate, in a former contaminated smelting site, the impact of two doses of wood biochar (2 and 5% w/w) on metal immobilization and/or phytoavailability and their effectiveness in promoting plant growth in mesocosm experiments. Different soil mixtures were investigated. The main physicochemical parameters and the Cd, Pb, and Zn contents were determined in soil and in soil pore water. Additionally, the growth, dry weight, and metal concentrations were analyzed in the different dwarf bean plant (Phaseolus vulgaris L.) organs tested. Results showed that the addition of biochar at two doses (2 and 5%) improved soil conditions by increasing soil pH, electrical conductivity, and water holding capacity. Furthermore, the application of biochar (5%) to metal-contaminated soil reduced Cd, Pb, and Zn mobility and availability, and hence their accumulation in the different P. vulgaris L. organs. In conclusion, the data clearly demonstrated that biochar application can be effectively used for Cd, Pb, and Zn immobilization, thereby reducing their bioavailability and phytotoxicity.

  12. Co-reduction of Copper Smelting Slag and Nickel Laterite to Prepare Fe-Ni-Cu Alloy for Weathering Steel

    Science.gov (United States)

    Guo, Zhengqi; Pan, Jian; Zhu, Deqing; Zhang, Feng

    2018-02-01

    In this study, a new technique was proposed for the economical and environmentally friendly recovery of valuable metals from copper smelting slag while simultaneously upgrading nickel laterite through a co-reduction followed by wet magnetic separation process. Copper slag with a high FeO content can decrease the liquidus temperature of the SiO2-Al2O3-CaO-MgO system and facilitate formation of liquid phase in a co-reduction process with nickel laterite, which is beneficial for metallic particle growth. As a result, the recovery of Ni, Cu, and Fe was notably increased. A crude Fe-Ni-Cu alloy with 2.5% Ni, 1.1% Cu, and 87.9% Fe was produced, which can replace part of scrap steel, electrolytic copper, and nickel as the burden in the production of weathering steel by an electric arc furnace. The study further found that an appropriate proportion of copper slag and nickel laterite in the mixture is essential to enhance the reduction, acquire appropriate amounts of the liquid phase, and improve the growth of the metallic alloy grains. As a result, the liberation of alloy particles in the grinding process was effectively promoted and the metal recovery was increased significantly in the subsequent magnetic separation process.

  13. Material and energy flows in rotary kiln-electric furnace smelting of ferronickel alloy with energy saving

    International Nuclear Information System (INIS)

    Liu, Peng; Li, Baokuan; Cheung, Sherman C.P.; Wu, Wenyuan

    2016-01-01

    Highlights: • Establish the synergy relationship of material and energy in key RKEF processes. • Develop an analysis model to study energy saving with internal cycling of energy. • Analyze material and energy flow parameters and assess its associated synergy effect. • A methodology to evaluate the synergy and design indices of RKEF processes. - Abstract: An energy saving strategy with two energy saving measures has been proposed for reducing energy loss in the rotary kiln-electric furnace (RKEF) for the smelting of ferronickel alloy. One of the measures is to recover the waste heat of exhaust gas from the rotary kiln for preheating and dehydrating the wet laterite ores in the rotary dryer. Another measure is to recycle the furnace gas from the electric furnace into the rotary kiln as fuel. Based on the mass conservation and energy conservation laws, an analysis model of material and energy flows has been developed to understand the potential energy saving with the internal cycling of material and energy in the RKEF process. The analysis model not only considers the energy efficiency but also assess the synergy degree of system. Furthermore, the model also predicts the ratio of raw materials and the energy flow distribution to investigate residual heat and energy and analyze the effects of nickel content on energy flow. Finally, the evaluation methodology of synergy and the technic indices are also presented. Through the investigation of the synergy effect, the performance of the RKEF process can be evaluated and quantified for performance optimization in future.

  14. [Evaluation and source analysis of the mercury pollution in soils and vegetables around a large-scale zinc smelting plant].

    Science.gov (United States)

    Liu, Fang; Wang, Shu-Xiao; Wu, Qing-Ru; Lin, Hai

    2013-02-01

    The farming soil and vegetable samples around a large-scale zinc smelter were collected for mercury content analyses, and the single pollution index method with relevant regulations was used to evaluate the pollution status of sampled soils and vegetables. The results indicated that the surface soil and vegetables were polluted with mercury to different extent. Of the soil samples, 78% exceeded the national standard. The mercury concentration in the most severely contaminated area was 29 times higher than the background concentration, reaching the severe pollution degree. The mercury concentration in all vegetable samples exceeded the standard of non-pollution vegetables. Mercury concentration, in the most severely polluted vegetables were 64.5 times of the standard, and averagely the mercury concentration in the vegetable samples was 25.4 times of the standard. For 85% of the vegetable samples, the mercury concentration, of leaves were significantly higher than that of roots, which implies that the mercury in leaves mainly came from the atmosphere. The mercury concentrations in vegetable roots were significantly correlated with that in soils, indicating the mercury in roots was mainly from soil. The mercury emissions from the zinc smelter have obvious impacts on the surrounding soils and vegetables. Key words:zinc smelting; mercury pollution; soil; vegetable; mercury content

  15. Lead in residential soil and dust in a mining and smelting district in northern Armenia: a pilot study

    International Nuclear Information System (INIS)

    Petrosyan, Varduhi; Orlova, Anna; Dunlap, Charles E.; Babayan, Emil; Farfel, Mark; Braun, Margrit von

    2004-01-01

    This pilot study of sources of lead exposure in residential settings was conducted in a mining and smelting district in northern Armenia. Samples of exterior soil and dust and interior house dust were collected in and around apartment buildings in Alaverdi where the country's largest polymetallic smelter is located, and in nearby mining towns of Aghtala and Shamlugh. The NITON XL-723 Multi-Element XRF analyzer was used for lead testing. Lead levels in samples from Alaverdi were higher than those in Shamlugh and Aghtala. In all three towns, the highest lead levels were found in loose exterior dust samples, and lead concentrations in yard soil were higher than those in garden soil. Many soil samples (34%) and the majority of loose dust samples (77%) in Alaverdi exceeded the US Environmental Protection Agency standard of 400 mg/kg for bare soil in children's play areas. In addition, 36% of floor dust samples from apartments in Alaverdi exceeded the US Environmental Protection Agency standard of 40 μg/ft 2 for lead loading in residential floor dust. The Armenian Ministry of Health and other interested agencies are being informed about the findings of the study so that they can consider and develop educational and preventive programs including blood lead screening among sensitive populations

  16. Numerical Investigation on the Impact of Anode Change on Heat Transfer and Fluid Flow in Aluminum Smelting Cells

    Science.gov (United States)

    Wang, Qiang; Gosselin, Louis; Fafard, Mario; Peng, Jianping; Li, Baokuan

    2016-04-01

    In order to understand the impact of anode change on heat transfer and magnetohydrodynamic flow in aluminum smelting cells, a transient three-dimensional (3D) coupled mathematical model has been developed. The solutions of the mass, momentum, and energy conservation equations were simultaneously implemented by the finite volume method with full coupling of the Joule heating and Lorentz force through solving the electrical potential equation. The volume of fluid approach was employed to describe the two-phase flow. The phase change of molten electrolyte (bath) as well as molten aluminum (metal) was modeled by an enthalpy-based technique, where the mushy zone is treated as a porous medium with a porosity equal to the liquid fraction. The effect of the new anode temperature on recovery time was also analyzed. A reasonable agreement between the test data and simulated results is obtained. The results indicate that the temperature of the bath under cold anodes first decreases reaching the minimal value and rises under the effect of increasing Joule heating, and finally returns to steady state. The colder bath decays the velocity, and the around ledge becomes thicker. The lowest temperature of the bath below new anodes increases from 1118 K to 1143 K (845 °C to 870 °C) with the new anode temperature ranging from 298 K to 498 K (25°C to 225°C), and the recovery time reduces from 22.5 to 20 hours.

  17. Geostatistical approach for assessing soil volumes requiring remediation: validation using lead-polluted soils underlying a former smelting works.

    Science.gov (United States)

    Demougeot-Renard, Helene; De Fouquet, Chantal

    2004-10-01

    Assessing the volume of soil requiring remediation and the accuracy of this assessment constitutes an essential step in polluted site management. If this remediation volume is not properly assessed, misclassification may lead both to environmental risks (polluted soils may not be remediated) and financial risks (unexpected discovery of polluted soils may generate additional remediation costs). To minimize such risks, this paper proposes a geostatistical methodology based on stochastic simulations that allows the remediation volume and the uncertainty to be assessed using investigation data. The methodology thoroughly reproduces the conditions in which the soils are classified and extracted at the remediation stage. The validity of the approach is tested by applying it on the data collected during the investigation phase of a former lead smelting works and by comparing the results with the volume that has actually been remediated. This real remediated volume was composed of all the remediation units that were classified as polluted after systematic sampling and analysis during clean-up stage. The volume estimated from the 75 samples collected during site investigation slightly overestimates (5.3% relative error) the remediated volume deduced from 212 remediation units. Furthermore, the real volume falls within the range of uncertainty predicted using the proposed methodology.

  18. Determination of the main parameters of the cyclone separator of the flue gas produced during the smelting of secondary aluminum

    Science.gov (United States)

    Matusov, Jozef; Gavlas, Stanislav

    2016-06-01

    One way how is possible to separate the solid particulate pollutants from the flue gas is use the cyclone separators. The cyclone separators are very frequently used separators due to the simplicity of their design and their low operating costs. Separation of pollutants in the form of solids is carried out using three types of forces: inertia force, centrifugal force, gravity force. The main advantage is that cyclone consist of the parts which are resistant to wear and have long life time, e.g. various rotating and sliding parts. Mostly are used as pre-separators, because they have low efficiency in the separation of small particles. Their function is to separate larger particles from the flue gases which are subsequently cleaned in the other device which is capable of removing particles smaller than 1 µm, which is limiting size of particle separation. The article will deal with the issue of calculating the basic dimensions and main parameters of the cyclone separator from flue gas produced during the smelting of secondary aluminum.

  19. Análisis y diseño de identidad visual con aplicaciones publicitarias y de producto: marca de ropa deportiva especializada en surf

    OpenAIRE

    Olea Fernández, Anna

    2017-01-01

    Aquest treball té com a objectiu principal veure quins canvis ha sofert la roba esportiva dins del surf i com han evolucionat els elements més significatius d'aquesta roba per, finalment, realitzar la creació dels elements gràfics més representatius sobre una marca de surf, especialitzada en roba esportiva. Durant l'estudi s'abastaran tots els processos necessaris on estan involucrats tant la figura del disseny gràfic com la creació dels elements gràfics més representatius d'una marca

  20. Vitamin A and contaminant concentrations in surf scoters (Melanitta perspicillata) wintering on the Pacific coast of British Columbia, Canada

    International Nuclear Information System (INIS)

    Harris, M.L.; Wilson, L.K.; Trudeau, S.F.; Elliott, J.E.

    2007-01-01

    Surf scoters are part of a community of sea ducks on the western coast of North America that have shown signs of long-term, unexplained declines in breeding bird numbers. Substantial numbers of scoters winter in the major harbours on the west coast, after breeding in the west-central northern boreal forest. To address the potential for contaminants to impact the health and survival of those birds, we investigated the condition and contamination of surf scoters during the winters of 1998-2001 at four foraging locations in the Strait of Georgia region of the Pacific coast of Canada. Vitamin A status was evaluated in liver and plasma samples collected from adults and juveniles, as part of a larger assessment of tissue contamination, body condition and biomarker responses. Individuals collected from a relatively contaminated site, Howe Sound, showed consistently low hepatic concentrations of retinol and retinyl palmitate forms of vitamin A, and gender-specific associations of retinyl palmitate with hepatic EROD activity. The relationship of hepatic retinol to retinyl palmitate was not constant across geographic locations, and a clear, linear relationship between the two forms of vitamin A was only evident in birds from the relatively uncontaminated site. This study also identified strong positive relationships between vitamin A and tissue burdens of cadmium and zinc. The positive association between hepatic retinyl palmitate and renal cadmium is similar to one observed in laboratory rats, in which a mechanism of interference with the controlled release of retinol from the liver was suggested

  1. A Comprehensive Motion Estimation Technique for the Improvement of EIS Methods Based on the SURF Algorithm and Kalman Filter.

    Science.gov (United States)

    Cheng, Xuemin; Hao, Qun; Xie, Mengdi

    2016-04-07

    Video stabilization is an important technology for removing undesired motion in videos. This paper presents a comprehensive motion estimation method for electronic image stabilization techniques, integrating the speeded up robust features (SURF) algorithm, modified random sample consensus (RANSAC), and the Kalman filter, and also taking camera scaling and conventional camera translation and rotation into full consideration. Using SURF in sub-pixel space, feature points were located and then matched. The false matched points were removed by modified RANSAC. Global motion was estimated by using the feature points and modified cascading parameters, which reduced the accumulated errors in a series of frames and improved the peak signal to noise ratio (PSNR) by 8.2 dB. A specific Kalman filter model was established by considering the movement and scaling of scenes. Finally, video stabilization was achieved with filtered motion parameters using the modified adjacent frame compensation. The experimental results proved that the target images were stabilized even when the vibrating amplitudes of the video become increasingly large.

  2. SURFS: Riding the waves with Synthetic UniveRses For Surveys

    Science.gov (United States)

    Elahi, Pascal J.; Welker, Charlotte; Power, Chris; Lagos, Claudia del P.; Robotham, Aaron S. G.; Cañas, Rodrigo; Poulton, Rhys

    2018-04-01

    We present the Synthetic UniveRses For Surveys (SURFS) simulations, a set of N-body/Hydro simulations of the concordance Λ Cold Dark Matter (ΛCDM) cosmology. These simulations use Planck cosmology, contain up to 10 billion particles, and sample scales and halo masses down to 1 kpc and 108 M⊙. We identify and track haloes from z = 24 to today using a state-of-the-art 6D halo finder and merger tree builder. We demonstrate that certain properties of haloes merger trees are numerically converged for haloes composed of ≳100 particles. Haloes smoothly grow in mass, Vmax, with the mass history characterized by log M(a) ∝ exp [-(a/β)α], where a is the scale factor, α(M) ≈ 0.8 & β(M) ≈ 0.024, with these parameters decreasing with decreasing halo mass. Subhaloes follow power-law cumulative mass and velocity functions, i.e. n( > f) ∝ f-α with αM = 0.83 ± 0.01 and α _{V_max}=2.13± 0.03 for mass and velocity, respectively, independent of redshift, as seen in previous studies. The halo-to-halo scatter in amplitude is 0.9 dex. The number of subhaloes in a halo weakly correlates with a halo's concentration c and spin λ:haloes of high c and low λ have 60 per cent more subhaloes than similar mass haloes of low c and high λ. High cadence tracking shows subhaloes are dynamic residents, with 25 per cent leaving their host halo momentarily, becoming a backsplash subhalo, and another 20 per cent changing hosts entirely, in agreement with previous studies. In general, subhaloes have elliptical orbits, e ≈ 0.6, with periods of 2.3^{+2.1}_{-1.7} Gyrs. Subhaloes lose most of their mass at pericentric passage with mass loss rates of ˜ 40 per cent Gyr-1. These catalogues will be made publicly available.

  3. Models and observations of foam coverage and bubble content in the surf zone

    Science.gov (United States)

    Kirby, J. T.; Shi, F.; Holman, R. A.

    2010-12-01

    column motion. Preliminary steps to calibrate and verify the resulting models will be taken based on results to be collected during the Surf Zone Optics experiment at Duck, NC in September 2010. Initial efforts will focus on an examination of breaking wave patterns and persistent foam distributions, using ARGUS imagery.

  4. Effect of solution heat treatment on the precipitation behavior and strengthening mechanisms of electron beam smelted Inconel 718 superalloy

    Energy Technology Data Exchange (ETDEWEB)

    You, Xiaogang [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China); Tan, Yi, E-mail: tanyi@dlut.edu.cn [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China); Shi, Shuang [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China); Yang, Jenn-Ming [Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095 (United States); Wang, Yinong [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Li, Jiayan; You, Qifan [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023 (China); Laboratory for New Energy Material Energetic Beam Metallurgical Equipment Engineering of Liaoning Province, Dalian 116024 (China)

    2017-03-24

    Inconel 718 superalloy was fabricated by electron beam smelting (EBS) technique. The effect of solution heat treatment on the precipitation behavior and mechanical properties of EBS 718 superalloys were studied, the strengthening mechanisms were analyzed and related to the mechanical properties. The results indicate that the optimized microstructures can be acquired by means of EBS, which is attributed to the rapid cooling rate of approximately 280 ℃/min. The solution heat treatment shows a great impact on the microstructures, precipitation behavior and mechanical properties of EBS 718 superalloy. The γ'' phase shows an apt to precipitate at relatively lower solution temperatures followed by aging, while the γ' precipitates are prone to precipitate at higher temperatures. When solution treated at 1150 ℃, the γ' precipitates are dispersively distributed in the matrix with size and volume fraction of 8.43 nm and 21.66%, respectively, a Vickers hardness of approximately 489 HV{sub 0.1} is observed for the aged superalloy. The precipitation strengthening effect of EBS 718 superalloy could be elucidated by considering the interaction between the dislocations and γ''/γ' precipitates. The shearing of γ' is resisted by the coherency strengthening and formation of antiphase boundary (APB), which shows equal effect as weakly coupled dislocation (WCD) model. And for γ'', the strengthening effect is much more prominent with the primary strengthening mechanism of ordering. Moreover, it is interestingly found that the strengthening mechanism of stacking fault (SF) shearing coexists with APB shearing, and SF shearing plays a major role in strengthening of EBS 718 superalloy.

  5. Effects of heavy metal pollution from mining and smelting on enchytraeid communities under different land management and soil conditions.

    Science.gov (United States)

    Kapusta, Paweł; Sobczyk, Łukasz

    2015-12-01

    We studied enchytraeid communities in several habitats polluted by heavy metals from Zn-Pb mining and smelting activities. We sampled 41 sites that differed in the type of substratum (carbonate rock, metal-rich carbonate mining waste, siliceous sand) and land management (planting Scots pine, topsoiling, leaving to natural succession), and the distance from the smelter. Our main aims were to determine which pollution variables and natural factors most influenced enchytraeid species composition, richness and density, and examine what was the effect of planting Scots pine (reclamation) on enchytraeid communities. The soils harboured on average 1 to 5 enchytraeid species and 700 to 18,300 individuals per square metre, depending on the habitat. These figures were generally lower than those reported from unpolluted regions. Redundancy and multiple regression analyses confirmed the negative impact of heavy metal pollution on both enchytraeid community structure and abundance. Among pollution variables, the distance from the smelter best explained the variation in enchytraeid communities. The concentrations of heavy metals in the soil had less (e.g. total Pb and exchangeable Zn) or negligible (water-soluble forms) explanatory power. Natural soil properties were nearly irrelevant for enchytraeids, except for soil pH, which determined the species composition. Plant species richness was an important explanatory variable, as it positively affected most parameters of enchytraeid community. The results of two-by-two factorial comparisons (planting Scots pine vs. natural succession; carbonate mining waste vs. siliceous sand) suggest that reclamation can improve soil quality for biota, since it increased the diversity and abundance of enchytraeids; this effect was not dependent on the type of substratum. In conclusion, enchytraeids responded negatively to heavy metal pollution and their response was consistent and clear. These animals can be used as indicators of metal toxicity

  6. Cleaning of a copper matte smelting slag from a water-jacket furnace by direct reduction of heavy metals.

    Science.gov (United States)

    Maweja, Kasonde; Mukongo, Tshikele; Mutombo, Ilunga

    2009-05-30

    Cleaning experiments of a copper matte smelting slag from the water-jacket furnace was undertaken by direct reduction in a laboratory-scale electric furnace. The effects of coal-to-slag ratio, w, and the reduction time, t, were considered for two different coal/slag mixing procedures. In the first procedure, metallurgical coal was added to the molten slag, whereas in the second procedure, coal was premixed with the solid slag before charging into the furnace. The recovery of heavy metals (Cu, Co), and the fuming of Pb and Zn were investigated. Contamination of the metal phase by iron and the acidity index of the final slag were analysed as these may impede the economical viability of the process. The lower w value of 2.56% yielded a recovery rate of less than 60% for copper and less than 50% for cobalt, and around 70% for zinc. However, increasing w to 5% allowed the recovery of 70-90% for Cu, Co and Zn simultaneously after 30-60 min reduction of the molten slag. After reduction, the cleaned slags contained only small amounts of copper and cobalt (zinc was efficient as the %Pb of the residual slag dropped to levels lower than 0.04% after 30 min of reduction. Ninety percent of the lead was removed from the initial slag and collected in the dusts. The zinc content of the cleaned slags quickly dropped to between 1 and 3 wt% from the initial 8.2% after 30 min reduction for w value of 5 and after 60 min reduction for w value of 2.56. The dusts contained about 60% Zn and 10% Pb. Recovery of lead from fuming of the slag was higher than 90% in all the experimental conditions considered in this study.

  7. Evaluation of a Surfing Programme Designed to Increase Personal Well-Being and Connectedness to the Natural Environment among "At Risk" Young People

    Science.gov (United States)

    Hignett, Amanda; White, Mathew P.; Pahl, Sabine; Jenkin, Rebecca; Froy, Mod Le

    2018-01-01

    Outdoor activities can be an important complement to classroom learning, especially for children/young people excluded, or at risk of exclusion, from mainstream schooling. The current research explored the impact of a 12-week surfing programme among such a group in the UK. Pre-post data on physiological health (heart rate (HR)/blood pressure),…

  8. On the use of the fictitious wave steepness and related surf-similarity parameters in methods that describe the hydraulic and structural response to waves

    NARCIS (Netherlands)

    Heineke, D.; Verhagen, H.J.

    2007-01-01

    To assess the hydraulic performance of coastal structures - viz. wave run-up, overtopping and reflection - and to evaluate the stability of the armour layers, use is made of the dimensionless surf similarity parameter, as introduced by Battjes (1974). The front side slope of the structure and the

  9. Emission and profile characteristic of volatile organic compounds emitted from coke production, iron smelt, heating station and power plant in Liaoning Province, China.

    Science.gov (United States)

    Shi, Jianwu; Deng, Hao; Bai, Zhipeng; Kong, Shaofei; Wang, Xiuyan; Hao, Jiming; Han, Xinyu; Ning, Ping

    2015-05-15

    107 kinds of C₂-C₁₂ volatile organic compound (VOC) mass concentrations and profiles for four types of coal-fired stationary sources in Liaoning Province were studied by a dilution sampling system and GC-MS analysis method, which are of significant importance with regard to VOC emissions in northeast of China. The results showed that there were some differences among these VOC source profiles. The total mass concentrations of analyzed 107 VOC species varied from 10,917 to 19,652 μg m(-3). Halogenated hydrocarbons exhibited higher mass percentages for the VOC source profiles of iron smelt (48.8%) and coke production plant (37.7%). Aromatic hydrocarbons were the most abundant in heating station plant (69.1%). Ketones, alcohols and acetates held 45.0% of total VOCs in thermal power plant. For non-methane hydrocarbons (NMHCs), which are demanded for photochemical assessment in the USA, toluene and n-hexane were the most abundant species in the iron smelt, coke production and thermal power plant, with the mass percentages of 64.8%, 52.7% and 38.6%, respectively. Trimethylbenzene, n-propylbenzene and o,m-ethyltoluene approximately accounted for 70.0% in heating station plant. NMHCs emitted from coke production, iron smelt, heating station and power plant listed above presented different chemical reactivities. The average OH loss rate of NMHCs from heating station, was 4 to 5.6 times higher than that of NMHCs from iron smelt, coke production and power plant, which implies that VOCs emitted from heating station in northeast of China should be controlled firstly to avoid photochemical ozone pollution and protect human health. There are significant variations in the ratios of benzene/toluene and m, p-xylene/ethylbenzene of these coal-fired source profiles. The representativeness of the coal-fired sources studied and the VOC samples collected should be more closely examined. The accuracy of VOC source profiles related to coal-fired processes is highly dependent on

  10. Post-depositional redistribution of trace metals in reservoir sediments of a mining/smelting-impacted watershed (the Lot River, SW France)

    International Nuclear Information System (INIS)

    Audry, Stephane; Grosbois, Cecile; Bril, Hubert; Schaefer, Joerg; Kierczak, Jakub; Blanc, Gerard

    2010-01-01

    Mining/smelting wastes and reservoir sediment cores from the Lot River watershed were studied using mineralogical (XRD, SEM-EDS, EMPA) and geochemical (redox dynamics, selective extractions) approaches to characterize the main carrier phases of trace metals. These two approaches permitted determining the role of post-depositional redistribution processes in sediments and their effects on the fate and mobility of trace metals. The mining/smelting wastes showed heterogeneous mineral compositions with highly variable contents of trace metals. The main trace metal-bearing phases include spinels affected by secondary processes, silicates and sulfates. The results indicate a clear change in the chemical partitioning of trace metals between the reservoir sediments upstream and downstream of the mining/smelting activities, with the downstream sediments showing a 2-fold to 5-fold greater contribution of the oxidizable fraction. This increase was ascribed to stronger post-depositional redistribution of trace metals related to intense early diagenetic processes, including dissolution of trace metal-bearing phases and precipitation of authigenic sulfide phases through organic matter (OM) mineralization. This redistribution is due to high inputs (derived from mining/smelting waste weathering) at the water-sediment interface of (i) dissolved SO 4 promoting more efficient OM mineralization, and (ii) highly reactive trace metal-bearing particles. As a result, the main trace metal-bearing phases in the downstream sediments are represented by Zn- and Fe-sulfides, with minor occurrence of detrital zincian spinels, sulfates and Fe-oxyhydroxides. Sequestration of trace metals in sulfides at depth in reservoir sediments does not represent long term sequestration owing to possible resuspension of anoxic sediments by natural (floods) and/or anthropogenic (dredging, dam flush) events that might promote trace metal mobilization through sulfide oxidation. It is estimated that, during a major

  11. Quantification of Surf Zone Bathymetry from Video Observations of Wave Breaking

    Science.gov (United States)

    Aarninkhof, S.; Ruessink, G.

    2002-12-01

    Cost-efficient methods to quantify surf zone bathymetry with high resolution in time and space would be of great value for coastal research and management. Automated video techniques provide the potential to do so. Time-averaged video observations of the nearshore zone show bright intensities at locations where waves preferentially break. Highly similar patterns are found from model simulations of depth-induced wave breaking, which show increasing rates of wave dissipation in shallow areas like sand bars. Thus, video observations of wave breaking - at least qualitatively - reflect sub-merged beach bathymetry. In search of the quantification of this relationship, we present a new model concept to map sub-merged beach bathymetry from time-averaged video images. This is achieved by matching model-predicted and video-observed rates of wave dissipation. First, time-averaged image intensities are sampled along a cross-shore array and interpreted in terms of a wave dissipation parameter. This involves a correction for the effect of persistent foam, which is visible at time-averaged video images but not predicted by common wave propagation models. The dissipation profiles thus obtained are used to update an initial beach bathymetry through optimisation of the match between measured and modelled rates of wave dissipation. The latter is done by raising the bottom elevation in areas where the measured dissipation rate exceeds the computed dissipation and vice versa. Since the model includes video data with high resolution in time (typically multiple images over a tidal cycle), it allows for virtually continous monitoring of surfzone bathymetry . Model tests against a synthetic data set of artificially generated wave dissipation profiles have shown the model's capability to accurately reconstruct beach bathymetry, over a wide range of morphological configurations. Maximum model deviations were found in the case of highly developed bar-trough systems (bar heights up to 4 m) and

  12. Attheya armata along the European Atlantic coast - The turn of the screw on the causes of "surf diatom"

    Science.gov (United States)

    Carballeira, R.; Leira, M.; López-Rodríguez, M. C.; Otero, X. L.

    2018-05-01

    The "surf diatom" species Attheya armata (West) Crawford accumulations have been detected in the coasts of Galicia (NW Spain) in recent years. However, unlike in other parts of the world, the current knowledge of the phenomenon in European coasts remains disperse and scarce. A multiple approach has been used to monitor a sector of the Galician coast and to evaluate chemical and biological parameters in the environment, as well as under in vitro culture conditions, with the aim of studying the causes underlying these episodes. Contrary to the general assumption, our results indicate no direct relationship between the ephemeral accumulation episodes occurrences with the continental discharges or nutrient levels in beach waters. The isotopic reference values for coastal food web in Galicia allows to affirm with certainty that A. armata accumulations is dominate by the sediment dynamics.

  13. Larval fish in the surf zone of Pontal do Sul beach, Pontal do Paraná, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Santiago Godefroid

    1999-01-01

    Full Text Available A total of 6,575 larvae in the preflexion, flexion and post-flexion stages of 15 families, 26 genera and 29 species were captured in the surf zone of Pontal do Sul beach, Paraná, Brazil. Samples of the families Gerreidae and Scianidae predominated and larvae of Eucinostomus argenteus (Baird&Girard, 1854, Micropogonias furnieri (Desmarest, 1823, Eucinostomus gula (Cuvier, 1830, Menticirrhus ameri-canus (Linnaeus, 1758 and Anchoa tricolor (Agassiz, 1829 were the most dominant species. Greater abundance of larvae was observed during the summer, followed by winter and in a less extent during spring and autumn. The number of species was greater in the summer, and there were no significant differences in the rest of the seasons.

  14. Dynamics of the relativistic acceleration of charged particles in space plasma while surfing the package electromagnetic waves

    International Nuclear Information System (INIS)

    Erokhin, N.S.; Zol'nikova, N.N.; Kuznetsov, E.A.; Mikhajlovskaya, L.A.

    2010-01-01

    Based on numerical calculations considered the relativistic acceleration of charged particles in space plasma when surfing on the spatially localized package of electromagnetic waves. The problem is reduced to the study of unsteady, nonlinear equation for the wave phase at the carrier frequency at the location of the accelerated charge, which is solved numerically. We study the temporal dynamics of the relativistic factor, the component of momentum and velocity of the particle, its trajectory is given gyro-rotation in an external magnetic field after the departure of the effective potential well. Dependence of the dynamics of a particle interacting with the wave of the sign of the velocity of the charge along the wave front. We formulate the optimal conditions of the relativistic particle acceleration wave packet, indicate the possibility of again (after a number gyro-turnover) charge trapping wave with an additional relativistic acceleration.

  15. Surfer’s myelopathy: a rare presentation in a non-surfing setting and review of the literature

    Science.gov (United States)

    Phan, Kevin; Hariswamy, Soumya; Rao, Prashanth J.

    2016-01-01

    Background Surfers myelopathy can be a rapidly devastating disease and little is known surrounding the pathophysiology of the condition. Although the classical pattern of illness has been well reported, it has never been observed in a non-surfing setting. Methods A 51-year-old demolition worker presented with acute non-traumatic myelopathy. Clinical examination revealed sensory loss to the level of L2. T2-MRI and MRI-DWI revealed a hyperintense signal suggestive of an ischaemic event. A diagnosis of surfer’s myelopathy was made and he was commenced on steroid therapy. Results Following steroid therapy and fluid management the patient was discharged after 6 days with minor anaethesia but significant overall neurological improvement. Conclusions Diagnosis of SM requires a thorough history, clinical examination and imaging (MRI, MRI-DWI). The patient should be admitted early and investigated. The use of rehabilitation services may be useful if available. PMID:27757436

  16. Exosomes surf on filopodia to enter cells at endocytic hot spots, traffic within endosomes, and are targeted to the ER.

    Science.gov (United States)

    Heusermann, Wolf; Hean, Justin; Trojer, Dominic; Steib, Emmanuelle; von Bueren, Stefan; Graff-Meyer, Alexandra; Genoud, Christel; Martin, Katrin; Pizzato, Nicolas; Voshol, Johannes; Morrissey, David V; Andaloussi, Samir E L; Wood, Matthew J; Meisner-Kober, Nicole C

    2016-04-25

    Exosomes are nanovesicles released by virtually all cells, which act as intercellular messengers by transfer of protein, lipid, and RNA cargo. Their quantitative efficiency, routes of cell uptake, and subcellular fate within recipient cells remain elusive. We quantitatively characterize exosome cell uptake, which saturates with dose and time and reaches near 100% transduction efficiency at picomolar concentrations. Highly reminiscent of pathogenic bacteria and viruses, exosomes are recruited as single vesicles to the cell body by surfing on filopodia as well as filopodia grabbing and pulling motions to reach endocytic hot spots at the filopodial base. After internalization, exosomes shuttle within endocytic vesicles to scan the endoplasmic reticulum before being sorted into the lysosome as their final intracellular destination. Our data quantify and explain the efficiency of exosome internalization by recipient cells, establish a new parallel between exosome and virus host cell interaction, and suggest unanticipated routes of subcellular cargo delivery. © 2016 Heusermann et al.

  17. Implementation and modification of a three-dimensional radiation stress formulation for surf zone and rip-current applications

    Science.gov (United States)

    Kumar, N.; Voulgaris, G.; Warner, John C.

    2011-01-01

    Regional Ocean Modeling System (ROMS v 3.0), a three-dimensional numerical ocean model, was previously enhanced for shallow water applications by including wave-induced radiation stress forcing provided through coupling to wave propagation models (SWAN, REF/DIF). This enhancement made it suitable for surf zone applications as demonstrated using examples of obliquely incident waves on a planar beach and rip current formation in longshore bar trough morphology (Haas and Warner, 2009). In this contribution, we present an update to the coupled model which implements a wave roller model and also a modified method of the radiation stress term based on Mellor (2008, 2011a,b,in press) that includes a vertical distribution which better simulates non-conservative (i.e., wave breaking) processes and appears to be more appropriate for sigma coordinates in very shallow waters where wave breaking conditions dominate. The improvements of the modified model are shown through simulations of several cases that include: (a) obliquely incident spectral waves on a planar beach; (b) obliquely incident spectral waves on a natural barred beach (DUCK'94 experiment); (c) alongshore variable offshore wave forcing on a planar beach; (d) alongshore varying bathymetry with constant offshore wave forcing; and (e) nearshore barred morphology with rip-channels. Quantitative and qualitative comparisons to previous analytical, numerical, laboratory studies and field measurements show that the modified model replicates surf zone recirculation patterns (onshore drift at the surface and undertow at the bottom) more accurately than previous formulations based on radiation stress (Haas and Warner, 2009). The results of the model and test cases are further explored for identifying the forces operating in rip current development and the potential implication for sediment transport and rip channel development. Also, model analysis showed that rip current strength is higher when waves approach at angles of 5

  18. Composition and Dynamics of the Nucleolinus, a Link between the Nucleolus and Cell Division Apparatus in Surf Clam (Spisula) Oocytes*

    Science.gov (United States)

    Alliegro, Mark C.; Hartson, Steven; Alliegro, Mary Anne

    2012-01-01

    The nucleolinus is a little-known cellular structure, discovered over 150 years ago (Agassiz, L. (1857) Contributions to the Natural History of the United States of America, First Monograph, Part IIL, Little, Brown and Co., Boston) and thought by some investigators in the late 19th to mid-20th century to function in the formation of the centrosomes or spindle. A role for the nucleolinus in formation of the cell division apparatus has recently been confirmed in oocytes of the surf clam, Spisula solidissima (Alliegro, M. A., Henry, J. J., and Alliegro, M. C. (2010) Proc. Natl. Acad. Sci. U.S.A. 107, 13718–13723). However, we know so little about the composition and dynamics of this compartment, it is difficult to construct mechanistic hypotheses or even to be sure that prior reports were describing analogous structures in the cells of mammals, amphibians, plants, and other organisms where it was observed. Surf clam oocytes are an attractive model to approach this problem because the nucleolinus is easily visible by light microscopy, making it accessible by laser microsurgery as well as isolation by common cell fractionation techniques. In this report, we analyze the macromolecular composition of isolated Spisula nucleolini and examine the relationship of this structure to the nucleolus and cell division apparatus. Analysis of nucleolinar RNA and protein revealed a set of molecules that overlaps with but is nevertheless distinct from the nucleolus. The proteins identified were primarily ones involved in nucleic acid metabolism and cell cycle regulation. Monoclonal antibodies generated against isolated nucleolini revealed centrosomal forerunners in the oocyte cytoplasm. Finally, induction of damage to the nucleolinus by laser microsurgery altered the trafficking of α- and γ-tubulin after fertilization. These observations strongly support a role for the nucleolinus in cell division and represent our first clues regarding mechanism. PMID:22219192

  19. The role of suspension events in cross-shore and longshore suspended sediment transport in the surf zone

    Science.gov (United States)

    Jaffe, Bruce E.

    2015-01-01

    Suspension of sand in the surf zone is intermittent. Especially striking in a time series of concentration are periods of intense suspension, suspension events, when the water column suspended sediment concentration is an order of magnitude greater than the mean concentration. The prevalence, timing, and contribution of suspension events to cross-shore and longshore suspended sediment transport are explored using field data collected in the inner half of the surf zone during a large storm at Duck, NC. Suspension events are defined as periods when the concentration is above a threshold. Events tended to occur during onshore flow under the wave crest, resulting in an onshore contribution to the suspended sediment transport. Even though large events occurred less than 10 percent of the total time, at some locations onshore transport associated with suspension events was greater than mean-current driven offshore-directed transport during non-event periods, causing the net suspended sediment transport to be onshore. Events and fluctuations in longshore velocity were not correlated. However, events did increase the longshore suspended sediment transport by approximately the amount they increase the mean concentration, which can be up to 35%. Because of the lack of correlation, the longshore suspended sediment transport can be modeled without considering the details of the intensity and time of events as the vertical integration of the product of the time-averaged longshore velocity and an event-augmented time-averaged concentration. However, to accurately model cross-shore suspended sediment transport, the timing and intensity of suspension events must be reproduced.

  20. Composition and dynamics of the nucleolinus, a link between the nucleolus and cell division apparatus in surf clam (Spisula) oocytes.

    Science.gov (United States)

    Alliegro, Mark C; Hartson, Steven; Alliegro, Mary Anne

    2012-02-24

    The nucleolinus is a little-known cellular structure, discovered over 150 years ago (Agassiz, L. (1857) Contributions to the Natural History of the United States of America, First Monograph, Part IIL, Little, Brown and Co., Boston) and thought by some investigators in the late 19th to mid-20th century to function in the formation of the centrosomes or spindle. A role for the nucleolinus in formation of the cell division apparatus has recently been confirmed in oocytes of the surf clam, Spisula solidissima (Alliegro, M. A., Henry, J. J., and Alliegro, M. C. (2010) Proc. Natl. Acad. Sci. U.S.A. 107, 13718-13723). However, we know so little about the composition and dynamics of this compartment, it is difficult to construct mechanistic hypotheses or even to be sure that prior reports were describing analogous structures in the cells of mammals, amphibians, plants, and other organisms where it was observed. Surf clam oocytes are an attractive model to approach this problem because the nucleolinus is easily visible by light microscopy, making it accessible by laser microsurgery as well as isolation by common cell fractionation techniques. In this report, we analyze the macromolecular composition of isolated Spisula nucleolini and examine the relationship of this structure to the nucleolus and cell division apparatus. Analysis of nucleolinar RNA and protein revealed a set of molecules that overlaps with but is nevertheless distinct from the nucleolus. The proteins identified were primarily ones involved in nucleic acid metabolism and cell cycle regulation. Monoclonal antibodies generated against isolated nucleolini revealed centrosomal forerunners in the oocyte cytoplasm. Finally, induction of damage to the nucleolinus by laser microsurgery altered the trafficking of α- and γ-tubulin after fertilization. These observations strongly support a role for the nucleolinus in cell division and represent our first clues regarding mechanism.

  1. A refined ecological risk assessment for California red-legged frog, Delta smelt, and California tiger salamander exposed to malathion.

    Science.gov (United States)

    Clemow, Yvonne H; Manning, Gillian E; Breton, Roger L; Winchell, Michael F; Padilla, Lauren; Rodney, Sara I; Hanzas, John P; Estes, Tammara L; Budreski, Katherine; Toth, Brent N; Hill, Katie L; Priest, Colleen D; Teed, R Scott; Knopper, Loren D; Moore, Dwayne Rj; Stone, Christopher T; Whatling, Paul

    2018-03-01

    The California red-legged frog (CRLF), Delta smelt (DS), and California tiger salamander (CTS) are 3 species listed under the United States Federal Endangered Species Act (ESA), all of which inhabit aquatic ecosystems in California. The US Environmental Protection Agency (USEPA) has conducted deterministic screening-level risk assessments for these species potentially exposed to malathion, an organophosphorus insecticide and acaricide. Results from our screening-level analyses identified potential risk of direct effects to DS as well as indirect effects to all 3 species via reduction in prey. Accordingly, for those species and scenarios in which risk was identified at the screening level, we conducted a refined probabilistic risk assessment for CRLF, DS, and CTS. The refined ecological risk assessment (ERA) was conducted using best available data and approaches, as recommended by the 2013 National Research Council (NRC) report "Assessing Risks to Endangered and Threatened Species from Pesticides." Refined aquatic exposure models including the Pesticide Root Zone Model (PRZM), the Vegetative Filter Strip Modeling System (VFSMOD), the Variable Volume Water Model (VVWM), the Exposure Analysis Modeling System (EXAMS), and the Soil and Water Assessment Tool (SWAT) were used to generate estimated exposure concentrations (EECs) for malathion based on worst-case scenarios in California. Refined effects analyses involved developing concentration-response curves for fish and species sensitivity distributions (SSDs) for fish and aquatic invertebrates. Quantitative risk curves, field and mesocosm studies, surface-water monitoring data, and incident reports were considered in a weight-of-evidence approach. Currently, labeled uses of malathion are not expected to result in direct effects to CRLF, DS or CTS, or indirect effects due to effects on fish and invertebrate prey. Integr Environ Assess Manag 2018;14:224-239. © 2017 The Authors. Integrated Environmental Assessment and

  2. Assessment of heavy metal pollution from a Fe-smelting plant in urban river sediments using environmental magnetic and geochemical methods

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Chunxia, E-mail: cxzhang@mail.iggcas.ac.cn [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19 Bei Tucheng Xilu, Chaoyang Dist., Beijing 100029 (China); Qiao Qingqing [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19 Bei Tucheng Xilu, Chaoyang Dist., Beijing 100029 (China); Piper, John D.A. [Geomagnetism Laboratory, Department of Earth and Ocean Science, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Huang, Baochun [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19 Bei Tucheng Xilu, Chaoyang Dist., Beijing 100029 (China)

    2011-10-15

    Environmental magnetic proxies provide a rapid means of assessing the degree of industrial heavy metal pollution in soils and sediments. To test the efficiency of magnetic methods for detecting contaminates from a Fe-smelting plant in Loudi City, Hunan Province (China) we investigated river sediments from Lianshui River. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these sediments. Anthropogenic heavy metals coexist with coarse-grained magnetic spherules. It can be demonstrated that the Pollution Load Index of industrial heavy metals (Fe, V, Cr, Mo, Zn, Pb, Cd, Cu) and the logarithm of saturation isothermal remanent magnetization, a proxy for magnetic concentration, are significantly correlated. The distribution heavy metal pollution in the Lianshui River is controlled by surface water transport and deposition. Our findings demonstrate that magnetic methods have a useful and practical application for detecting and mapping pollution in and around modern industrial cities. - Highlights: > Assessment of heavy metal (HM) pollution in river sediment using magnetic and chemical methods. > HMs from an Fe-smelting plant coexist with coarse-grained magnetic spherules. > A linear correlation between the Pollution Load Index (PLI) of industrial HMs and a magnetic concentration parameter is demonstrated. > The distribution of HM pollution in river sediments is controlled by surface water flow and deposition. - Heavy metal (HM) contamination of river sediments from industrial input by surface water transport and deposition can be detected by using magnetic methods providing a convenient assessment of HM pollution in industrialized cities.

  3. Effects of Basicity and MgO in Slag on the Behaviors of Smelting Vanadium Titanomagnetite in the Direct Reduction-Electric Furnace Process

    Directory of Open Access Journals (Sweden)

    Tao Jiang

    2016-05-01

    Full Text Available The effects of basicity and MgO content on reduction behavior and separation of iron and slag during smelting vanadium titanomagnetite by electric furnace were investigated. The reduction behaviors affect the separation of iron and slag in the direct reduction-electric furnace process. The recovery rates of Fe, V, and Ti grades in iron were analyzed to determine the effects of basicity and MgO content on the reduction of iron oxides, vanadium oxides, and titanium oxides. The chemical compositions of vanadium-bearing iron and main phases of titanium slag were detected by XRF and XRD, respectively. The results show that the higher level of basicity is beneficial to the reduction ofiron oxides and vanadium oxides, and titanium content dropped in molten iron with the increasing basicity. As the content of MgO increased, the recovery rate of Fe increased slightly but the recovery rate of V increased considerably. The grades of Ti in molten iron were at a low level without significant change when MgO content was below 11%, but increased as MgO content increased to 12.75%. The optimum conditions for smelting vanadium titanomagnetite were about 11.38% content of MgO and quaternary basicity was about 1.10. The product, vanadium-bearing iron, can be applied in the converter steelmaking process, and titanium slag containing 50.34% TiO2 can be used by the acid leaching method.

  4. Assessment of heavy metal pollution from a Fe-smelting plant in urban river sediments using environmental magnetic and geochemical methods

    International Nuclear Information System (INIS)

    Zhang Chunxia; Qiao Qingqing; Piper, John D.A.; Huang, Baochun

    2011-01-01

    Environmental magnetic proxies provide a rapid means of assessing the degree of industrial heavy metal pollution in soils and sediments. To test the efficiency of magnetic methods for detecting contaminates from a Fe-smelting plant in Loudi City, Hunan Province (China) we investigated river sediments from Lianshui River. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these sediments. Anthropogenic heavy metals coexist with coarse-grained magnetic spherules. It can be demonstrated that the Pollution Load Index of industrial heavy metals (Fe, V, Cr, Mo, Zn, Pb, Cd, Cu) and the logarithm of saturation isothermal remanent magnetization, a proxy for magnetic concentration, are significantly correlated. The distribution heavy metal pollution in the Lianshui River is controlled by surface water transport and deposition. Our findings demonstrate that magnetic methods have a useful and practical application for detecting and mapping pollution in and around modern industrial cities. - Highlights: → Assessment of heavy metal (HM) pollution in river sediment using magnetic and chemical methods. → HMs from an Fe-smelting plant coexist with coarse-grained magnetic spherules. → A linear correlation between the Pollution Load Index (PLI) of industrial HMs and a magnetic concentration parameter is demonstrated. → The distribution of HM pollution in river sediments is controlled by surface water flow and deposition. - Heavy metal (HM) contamination of river sediments from industrial input by surface water transport and deposition can be detected by using magnetic methods providing a convenient assessment of HM pollution in industrialized cities.

  5. Distribution and transfer of potentially toxic metal(loid)s in Juncus effusus from the indigenous zinc smelting area, northwest region of Guizhou Province, China.

    Science.gov (United States)

    Peng, Yishu; Chen, Jun; Wei, Huairui; Li, Shibin; Jin, Tao; Yang, Ruidong

    2018-05-15

    We collected samples (i.e., the aerial parts and roots of Juncus effusus and their growth media) in the indigenous zinc smelting area in the northwest region of Guizhou Province, China, and we measured and analyzed potentially toxic metal(loid)s (arsenic, As; cadmium, Cd; chromium, Cr; copper, Cu; mercury, Hg; lead, Pb and zinc, Zn) in these samples. The results include the following: First, there is a high concentration of one or more potentially toxic metal(loid)s in the slag and surrounding soil in the research area. This situation might be caused by metal(loid) damage or contamination due to the circumstances. Additionally, Juncus effusus in the indigenous zinc smelting area are contaminated by some potentially toxic metal(loid)s; since they are used for Chinese medical materials, it is especially significant that their As, Cd and Pb concentrations are greater than their limited standard values. Finally, both the bioconcentration factors and transfer factors for most potentially toxic metal(loid)s in Juncus effusus are less than 1 in the study area. Therefore, we suggest that Juncus effusus could be used for phytostabilization or as a pioneer plant for phytoremediation of potentially toxic metal(loid)s because it has a tolerance and exclusion mechanism for these metal(loid)s in the research district. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Nová missense mutace 574C>T v genu SURF1 - biochemická a molekulárně genetická studie u sedmi dětí s Leighovým syndromem

    Czech Academy of Sciences Publication Activity Database

    Čapková, M.; Hansíková, H.; Godinot, C.; Houšťková, H.; Houštěk, Josef; Zeman, J.

    2002-01-01

    Roč. 141, č. 20 (2002), s. 636-641 ISSN 0008-7335 R&D Projects: GA MZd NE6555 Grant - others:GA UK(CZ) 8/2000/C; CZ - FR(XC) Projekt Barrande 2001/028-1 Institutional research plan: CEZ:AV0Z5011922 Keywords : Leigh syndrome * SURF1 gene * SURF1 protein Subject RIV: EB - Genetics ; Molecular Biology

  7. Nová missense mutace 574C>T v genu SURF1 - biochemická a molekulárně genetická studie u sedmi dětí s Leighovým syndromem

    Czech Academy of Sciences Publication Activity Database

    Čapková, M.; Hansíková, H.; Godinot, C.; Houšťková, H.; Houštěk, Josef; Zeman, J.

    2002-01-01

    Roč. 141, č. 20 (2002), s. 636-641 ISSN 0008-7335 R&D Projects: GA MZd(CZ) NE6555; GA MŠk(CZ) LN00A079 Grant - others:GA UK(CZ) 8/2000/C; FR-CZ(CZ) Barrande 2001/028-1 Institutional research plan: CEZ:AV0Z5011922 Keywords : Leigh syndrome * SURF1 gene * Surf1 protein Subject RIV: EB - Genetics ; Molecular Biology

  8. The aluminum smelting process.

    Science.gov (United States)

    Kvande, Halvor

    2014-05-01

    This introduction to the industrial primary aluminum production process presents a short description of the electrolytic reduction technology, the history of aluminum, and the importance of this metal and its production process to modern society. Aluminum's special qualities have enabled advances in technologies coupled with energy and cost savings. Aircraft capabilities have been greatly enhanced, and increases in size and capacity are made possible by advances in aluminum technology. The metal's flexibility for shaping and extruding has led to architectural advances in energy-saving building construction. The high strength-to-weight ratio has meant a substantial reduction in energy consumption for trucks and other vehicles. The aluminum industry is therefore a pivotal one for ecological sustainability and strategic for technological development.

  9. Spatial and temporal variations of diurnal ichthyofauna on surf-zone of São Francisco do Itabapoana beaches, Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Gomes Marcelo Paes

    2003-01-01

    Full Text Available Spatial and temporal variations of diurnal ichthyofauna and the environmental variables influences on its distribution were studied at the surf-zone of three beaches of São Francisco do Itabapoana, northern coast of Rio de Janeiro, Brazil. From August/1999 to August/2000, three beach seine hauls were made monthly, and environmental variables were recorded. A total number of 4,562 fishes (74,155g were sampled at the three beaches, where estuarine-dependent species prevailed (44%, followed by marine (31%, estuarine (19% and freshwater species (3%. Species richness, number of individuals and wet weight were significantly higher at Gargaú, followed by Manguinhos and Barra do Itabapoana, respectively. Canonical Correspondence Analysis highlighted influences of the rivers flushing, salinity and plant abundance on the diurnal ichthyofauna distribution and dynamics of São Francisco do Itabapoana surf-zone.

  10. Interruptions in Chest Compressions by Surf Lifeguards: A Comparison of Face-mask Ventilation in Over-the-head CPR vs Standard CPR

    DEFF Research Database (Denmark)

    Nørkjær, Louise; Nielsen, Lars Henrik; Bomholt, Katrine Bjørnshave

    . The International Life Saving Federation recommends CPR using face-mask ventilation. It is currently unknown if OH-CPR using face-mask ventilation improves CPR quality. We hypothesized that OH-CPR is superior to standard CPR with face-mask ventilation among surf lifeguards. Methods: Surf lifeguards were trained......Introduction: Ventilation is a priority in drowning resuscitation. Over-the-head CPR (OH-CPR), i.e. with the rescuer located at the top of the victim’s head instead of alongside the victim’s torso, has been demonstrated to be superior when doing bag-valve-mask ventilation compared to standard CPR...... in OH-CPR and standard CPR with face-mask ventilation and randomized to a crossover comparison on a manikin. CPR quality data were obtained from the manikin and video recordings. Interruptions in chest compressions were used as a primary measure of CPR quality. A sample size of 14 participants...

  11. Retrieval system for emplaced spent unreprocessed fuel (SURF) in salt bed depository: accident event analysis and mechanical failure probabilities. Final report

    International Nuclear Information System (INIS)

    Bhaskaran, G.; McCleery, J.E.

    1979-10-01

    This report provides support in developing an accident prediction event tree diagram, with an analysis of the baseline design concept for the retrieval of emplaced spent unreprocessed fuel (SURF) contained in a degraded Canister. The report contains an evaluation check list, accident logic diagrams, accident event tables, fault trees/event trees and discussions of failure probabilities for the following subsystems as potential contributors to a failure: (a) Canister extraction, including the core and ram units; (b) Canister transfer at the hoist area; and (c) Canister hoisting. This report is the second volume of a series. It continues and expands upon the report Retrieval System for Emplaced Spent Unreprocessed Fuel (SURF) in Salt Bed Depository: Baseline Concept Criteria Specifications and Mechanical Failure Probabilities. This report draws upon the baseline conceptual specifications contained in the first report

  12. A novel mutation in SURF1 causes skipping of exon 8 in a patient with cytochrome c oxidase-deficient leigh syndrome and hypertrichosis

    Czech Academy of Sciences Publication Activity Database

    Williams, S. L.; Taanman, J. W.; Hansíková, H.; Houšťková, H.; Chowdhury, Subir; Zeman, J.; Houštěk, Josef

    2001-01-01

    Roč. 73, č. 4 (2001), s. 340-343 ISSN 1096-7192 R&D Projects: GA MŠk LN00A079; GA ČR GA302/99/0648; GA MZd NE6533 Grant - others:The Wellcome Trust(XX) 048410 Institutional research plan: CEZ:AV0Z5011922 Keywords : SURF1 * exon skipping * mitochondrial disorder Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.345, year: 2001

  13. Evaluation of a surfing programme designed to increase personal well-being and connectedness to the natural environment among ‘at risk’ young people

    OpenAIRE

    Hignett, A; White, MP; Pahl, S; Jenkin, R; Froy, ML

    2018-01-01

    © 2017 Institute for Outdoor Learning. Outdoor activities can be an important complement to classroom learning, especially for children/young people excluded, or at risk of exclusion, from mainstream schooling. The current research explored the impact of a 12-week surfing programme among such a group in the UK. Pre-post data on physiological health (heart rate (HR)/blood pressure), self-reported well-being (life and domain satisfaction), connectedness (e.g. to nature, school), environmental a...

  14. SURF: a subroutine code to draw the axonometric projection of a surface generated by a scalar function over a discretized plane domain using finite element computations

    International Nuclear Information System (INIS)

    Giuliani, Giovanni; Giuliani, Silvano.

    1980-01-01

    The FORTRAN IV subroutine SURF has been designed to help visualising the results of Finite Element computations. It drawns the axonometric projection of a surface generated in 3-dimensional space by a scalar function over a discretized plane domain. The most important characteristic of the routine is to remove the hidden lines and in this way it enables a clear vision of the details of the generated surface

  15. Three-dimensional modelling of wave-induced current from the surf zone to the inner shelf

    Directory of Open Access Journals (Sweden)

    H. Michaud

    2012-08-01

    Full Text Available We develop and implement a new method to take into account the impact of waves into the 3-D circulation model SYMPHONIE (Marsaleix et al., 2008, 2009a following the simplified equations of Bennis et al. (2011 which use glm2z-RANS theory (Ardhuin et al., 2008c. These adiabatic equations are completed by additional parameterizations of wave breaking, bottom friction and wave-enhanced vertical mixing, making the forcing valid from the surf zone through to the open ocean. The wave forcing is performed by wave generation and propagation models WAVEWATCH III® (Tolman, 2008, 2009; Ardhuin et al., 2010 and SWAN (Booij et al., 1999. The model is tested and compared with other models for a plane beach test case, previously tested by Haas and Warner (2009and Uchiyama et al. (2010. A comparison is also made with the laboratory measurements of Haller et al. (2002 of a barred beach with channels. Results fit with previous simulations performed by other models and with available observational data.

    Finally, a realistic case is simulated with energetic waves travelling over a coast of the Gulf of Lion (in the northwest of the Mediterranean Sea for which currents are available at different depths as well as an accurate bathymetric database of the 0–10 m depth range. A grid nesting approach is used to account for the different forcings acting at different spatial scales. The simulation coupling the effects of waves and currents is successful to reproduce the powerful northward littoral drift in the 0–15 m depth zone. More precisely, two distinct cases are identified: When waves have a normal angle of incidence with the coast, they are responsible for complex circulation cells and rip currents in the surf zone, and when they travel obliquely, they generate a northward littoral drift. These features are more complicated than in the test cases, due to the complex bathymetry and the consideration of wind and non-stationary processes. Wave impacts in the

  16. Structure and diversity of ground mesofauna inUlmus and Populus consortia in the industrial areas of mining and smelting complex of krivyi rig basin

    Directory of Open Access Journals (Sweden)

    V. V. Kachinskaya

    2010-05-01

    Full Text Available The structure and biological diversity of ground mesofauna on a consortium level of organisation of ecosystems are considered. Indicators of structural organisation and biodiversity of ground mesofauna were analised in Ulmus and Populus consortia in the conditions of industrial territories of mining and smelting complex of Krivyi Rig Basin. It is established that taxonomical structure of ground mesofauna is characterised by insignificant number and quantity of taxonomical groups. Prevalence of hortobionts and herpetobionts in morpho-ecological structure of the community testifies to their attachment to consortium’s determinants and influence of steppe climate on its structure. Dominance of phytophages and polyphages in trophic structure is caused by a combination of consortium determinants specificity and «a zone source» of the fauna formations. The structural organisation of ground mesofauna in consortia of Ulmus and Populus in the conditions of industrial sites is characterised by simplified taxonomical structure with low biodiversity at all levels.

  17. The effect of smelting time and composition of palm kernel shell charcoal reductant toward extractive Pomalaa nickel laterite ore in mini electric arc furnace

    Science.gov (United States)

    Sihotang, Iqbal Huda; Supriyatna, Yayat Iman; Ismail, Ika; Sulistijono

    2018-04-01

    Indonesia is a country that is rich in natural resources. Being a third country which has a nickel laterite ore in the world after New Caledonia and Philippines. However, the processing of nickel laterite ore to increase its levels in Indonesia is still lacking. In the processing of nickel laterite ore into metal, it can be processed by pyrometallurgy method that typically use coal as a reductant. However, coal is a non-renewable energy and have high enough levels of pollution. One potentially replace is the biomass, that is a renewable energy. Palm kernel shell are biomass that can be used as a reductant because it has a fairly high fix carbon content. This research aims to make nickel laterite ores become metal using palm kernel shell charcoal as reductant in mini electric arc furnace. The result show that the best smelting time of this research is 60 minutes with the best composition of the reductant is 2,000 gram.

  18. Determination of the elemental composition of aerosol samples in the working environment of a secondary lead smelting company in Nigeria using EDXRF technique

    International Nuclear Information System (INIS)

    Obiajunwa, E.I.; Johnson-Fatokun, F.O.; Olaniyi, H.B.; Olowole, A.F.

    2002-01-01

    Energy dispersive X-ray fluorescence technique was employed to determine the concentrations of elements in aerosol samples collected in the working environment of a secondary lead smelting company in Nigeria. Sampling was done using Whatman-41 cellulose filters mounted in Negretti air samplers at 10 locations within the factory. The concentrations of eight elements (K, Ca, Ti, Mn, Fe, Cu, Zn and Pb) were determined. The TSP values ranged from 70 to 7963 μg/m 3 and the concentration of Pb was found to be between 2.98 and 538.47 μg/m 3 . The high Pb concentration is a danger signal to the health of the factory workers

  19. Standardization of the process of smelting for sands with self-forgeling resins in the Military Industry Santa Bárbara Factory

    Directory of Open Access Journals (Sweden)

    Lina Consuelo Carvajal-Fernández

    2014-12-01

    Full Text Available This article describes the standardization of the smelting process for sands with self-forgeling resins in the Military Industry Santa Barbara Factory. The molding process was studied in the Smelter for six months, to set standards for workforce and raw materials, so that would allow truthfully evaluate the costs per kilogram of casting. 41 pieces of civil and military sectors throughout the development of the project were worked. Finally both standards were evaluated, labor as raw material for different parts, with results was evidenced improved process, essentially in workforce, while in raw material standards did not show significantly change, in this case is corroborated that existing ones are applicable to the process

  20. Effect of Calcium Oxide on the Crushing Strength, Reduction, and Smelting Performance of High-Chromium Vanadium–Titanium Magnetite Pellets

    Directory of Open Access Journals (Sweden)

    Gongjin Cheng

    2017-05-01

    Full Text Available The effect of calcium oxide on the crushing strength, reduction, and smelting performance of high-chromium vanadium–titanium magnetite pellets (HCVTMP was studied in this work. The main characterization methods of an electronic universal testing machine (EUTM, X-ray fluorescent (XRF, inductively-coupled plasma-atomic emission spectroscopy (ICP-AES, X-ray diffraction (XRD, and scanning electron microscope-energy disperse spectroscopy (SEM-EDS were employed. The crushing strength was affected by the mineral phases generated during oxidative baking and the subsequently-formed pellet microstructures owing to CaO addition. The reduction and smelting properties of HCVTMP with different CaO additives were measured and characterized with different softening-melting-dripping indices. Although HCVTMP showed the highest crushing strength with CaO addition of ca. 2 wt %, more CaO addition may be needed to achieve high permeability of the furnace burdens and a good separation condition of the slag and melted iron. In the formation process of the slag and melted iron, it can be determined that CaO could have a relationship with the transformation behavior of Cr, V, and Ti to some extent, with respect to the predominant chemical composition analysis of ICP-AES and XRF. With the microscopic examination, the restraining formation of Ti(C,N and the promoting formation of CaTiO3 are in accordance with the improved melting-dripping indices, including the decrease of the maximum external static load and gas permeability, and the increase of the melting-dripping zone and dripping difficulty.

  1. Multi-criteria analysis of soil pollution by heavy metals in the vicinity of the Copper Smelting Plant in Bor (Serbia

    Directory of Open Access Journals (Sweden)

    NEVENKA PETROVIĆ

    2011-04-01

    Full Text Available This study highlights the consequences on soil pollution of one hund­red years of manufacturing in the Copper Mining and Smelting Complex RTB-Bor (Serbia. Soil sediments were taken via a probe from the surface layer of the soil at twelve different measuring points. The measuring points were all within 20 km of the smelting plant, which included both urban and rural zones. Soil sampling was performed using a soil core sampler in such way that a core of a soil of radius 5 cm and depth of 30 cm was removed. Subsequently, the samples were analyzed for pH and heavy metal concentrations (Cu, Pb, As, Cd, Mn, Ni and Hg using different spectrometric methods. The obtained results for the heavy metal contents in the samples show high values: 2,540 mg kg-1 Cu; 230 mg kg-1 Pb; 6 mg kg-1 Cd; 530 mg kg-1 Ni; 1,300 mg kg-1 Mn; 260 mg kg-1 As and 0.3 mg kg-1 Hg. In this study, critical zones of polluted soil were iden­tified and ranked according to their metal contents by the multi-criteria deci­sion method Preference Organization Method for Enrichment Evaluation/Geo­metrical Analysis for Interactive Assistance – PROMETHEE/GAIA, which is the preferred multivariate method commonly used in chemometric studies. The ranking results clearly showed that the most polluted zones are at locations holding the vital functions of the town. Therefore, due to the high bioavail­abi­lity of heavy metals through com­plex reactions with organic species in the sediments, consequences for human health could drastically emerge if these metals enter the food chain.

  2. Measuring Temperature-Dependent Propagating Disturbances in Coronal Fan Loops Using Multiple SDO-AIA Channels and Surfing Transform Technique

    Science.gov (United States)

    Uritskiy, Vadim M.; Davila, Joseph M.; Viall, Nicholeen M.; Ofman, Leon

    2013-01-01

    A set of co-aligned high resolution images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO) is used to investigate propagating disturbances (PDs) in warm fan loops at the periphery of a non-flaring active region NOAA AR 11082. To measure PD speeds at multiple coronal temperatures, a new data analysis methodology is proposed enabling quantitative description of sub visual coronal motions with low signal-to-noise ratios of the order of 0.1. The technique operates with a set of one-dimensional surfing signals extracted from position-timeplots of several AIA channels through a modified version of Radon transform. The signals are used to evaluate a two-dimensional power spectral density distribution in the frequency - velocity space which exhibits a resonance in the presence of quasi-periodic PDs. By applying this analysis to the same fan loop structures observed in several AIA channels, we found that the traveling velocity of PDs increases with the temperature of the coronal plasma following the square root dependence predicted for the slow mode magneto-acoustic wave which seems to be the dominating wave mode in the studied loop structures. This result extends recent observations by Kiddie et al. (2012) to a more general class of fan loop systems not associated with sunspots and demonstrating consistent slow mode activity in up to four AIA channels.

  3. PADDLING PERFORMANCE AND RANKING POSITION IN JUNIOR SURFERS COMPETING AT THE ASSOCIATION OF SURFING PROFESSIONALS: A PILOT STUDY

    Directory of Open Access Journals (Sweden)

    Jesús Cámara

    2011-11-01

    Full Text Available Abstract  The aims of this pilot study are on one hand, to evaluate the upper body aerobic characteristics of junior surfers competing at the European branch of the Association of Surfing Professionals (ASP and on the other, to assess the relationship between the junior surfers' upper body aerobic characteristics and their ranking position. Ten surfers competing at the European junior branch of the ASP took part in the study. The maximal oxygen uptake (VO2MAX, the maximum power output (WMAX, the maximum lactate concentration [La]MAX, the maximum heart rate (HRMAX and the power output at the intensity where the lactate threshold and the onset of blood lactate accumulation are produced (WLT and WOBLA were determined during an incremental maximal test in a swim bench ergometer. It was observed a lack of a significant relationship between the ranking position and the parameters at maximal intensity (VO2PEAK, WMAX, HRMAX y [La]MAX. The WLT (W · kg-1 and the WOBLA (W · kg-1 were significantly related to ranking position (r= -0.69, p= 0.02; r= -0.72, p= 0.01, respectively.

  4. Diel cycles of hydrogen peroxide in marine bathing waters in Southern California, USA: In situ surf zone measurements

    International Nuclear Information System (INIS)

    Clark, Catherine D.; De Bruyn, Warren J.; Hirsch, Charlotte M.; Aiona, Paige

    2010-01-01

    Hydrogen peroxide is photochemically produced in natural waters. It has been implicated in the oxidative-induced mortality of fecal indicator bacteria (FIB), a microbial water quality measure. To assess levels and cycling of peroxide in beach waters monitored for FIB, diel studies were carried out in surf zone waters in July 2009 at Crystal Cove State Beach, Southern California, USA. Maximum concentrations of 160-200 nM were obtained within 1 h of solar noon. Levels dropped at night to 20-40 nM, consistent with photochemical production from sunlight. Day-time production and night-time dark loss rates averaged 16 ± 3 nM h -1 and 12 ± 4 nM h -1 respectively. Apparent quantum yields averaged 0.07 ± 0.02. Production was largely dominated by sunlight, with some dependence on chromophoric dissolved organic matter (CDOM) levels in waters with high absorption coefficients. Peroxide levels measured here are sufficient to cause oxidative-stress-induced mortality of bacteria, affect FIB diel cycling and impact microbial water quality in marine bathing waters.

  5. Post-release survival of surf scoters following an oil spill: an experimental approach to evaluating rehabilitation success

    Science.gov (United States)

    De La Cruz, Susan E. W.; Takekawa, John Y.; Spragens, Kyle A.; Yee, Julie; Golightly, Richard T.; Massey, Greg; Henkel, Laird A.; Larsen, Scott; Ziccardi, Michael

    2013-01-01

    Birds are often the most numerous vertebrates damaged and rehabilitated in marine oil spills; however, the efficacy of avian rehabilitation is frequently debated and rarely examined experimentally. We compared survival of three radio-marked treatment groups, oiled, rehabilitated (ORHB), un-oiled, rehabilitated (RHB), and un-oiled, non-rehabilitated (CON), in an experimental approach to examine post-release survival of surf scoters (Melanitta perspicillata) following the 2007 M/V Cosco Busan spill in San Francisco Bay. Live encounter-dead recovery modeling indicated that survival differed among treatment groups and over time since release. The survival estimate (±SE) for ORHB was 0.143 ± 0.107 compared to CON (0.498 ± 0.168) and RHB groups (0.772 ± 0.229), suggesting scoters tolerated the rehabilitation process itself well, but oiling resulted in markedly lower survival. Future efforts to understand the physiological effects of oil type and severity on scoters are needed to improve post-release survival of this species.

  6. A feasibility study of predictable and unpredictable surf-like sounds for tinnitus therapy using personal music players.

    Science.gov (United States)

    Durai, Mithila; Kobayashi, Kei; Searchfield, Grant D

    2018-05-28

    To evaluate the feasibility of predictable or unpredictable amplitude-modulated sounds for tinnitus therapy. The study consisted of two parts. (1) An adaptation experiment. Loudness level matches and rating scales (10-point) for loudness and distress were obtained at a silent baseline and at the end of three counterbalanced 30-min exposures (silence, predictable and unpredictable). (2) A qualitative 2-week sound therapy feasibility trial. Participants took home a personal music player (PMP). Part 1: 23 individuals with chronic tinnitus and part 2: seven individuals randomly selected from Part 1. Self-reported tinnitus loudness and annoyance were significantly lower than baseline ratings after acute unpredictable sound exposure. Tinnitus annoyance ratings were also significantly lower than the baseline but the effect was small. The feasibility trial identified that participant preferences for sounds varied. Three participants did not obtain any benefit from either sound. Three participants preferred unpredictable compared to predictable sounds. Some participants had difficulty using the PMP, the average self-report hours of use were low (less <1 h/day). Unpredictable surf-like sounds played using a PMP is a feasible tinnitus treatment. Further work is required to improve the acceptance of the sound and ease of PMP use.

  7. Assessments at multiple levels of biological organization allow for an integrative determination of physiological tolerances to turbidity in an endangered fish species

    OpenAIRE

    Hasenbein, Matthias; Fangue, Nann A.; Geist, Juergen; Komoroske, Lisa M.; Truong, Jennifer; McPherson, Rina; Connon, Richard E.

    2016-01-01

    Turbidity can influence trophic levels by altering species composition and can potentially affect fish feeding strategies and predator?prey interactions. The estuarine turbidity maximum, described as an area of increased suspended particles, phytoplankton and zooplankton, generally represents a zone with higher turbidity and enhanced food sources important for successful feeding and growth in many fish species. The delta smelt (Hypomesus transpacificus) is an endangered, pelagic fish species ...

  8. Pencarian Produk yang Mirip Melalui Automatic Online Annotation dari Web dan Berbasiskan Konten dengan Color Histogram Bin dan Surf Descriptor

    Directory of Open Access Journals (Sweden)

    Putra Pandu Adikara

    2018-03-01

    Full Text Available Banyaknya situs e-commerce memberikan kemudahan bagi pengguna yang ingin mencari dan membeli suatu produk, misalnya membeli makanan, obat, alat elektronik, kebutuhan sehari-hari, dan lain-lain. Pencarian suatu produk terhadap beberapa situs e-commerce akan menjadi sulit karena banyaknya pilihan situs, banyaknya penjual (merchant/seller yang menjual barang yang sama, dan waktu yang lama karena harus berpindah-pindah situs hingga menemukan produk yang diinginkan. Selain itu dengan adanya teknologi smartphone berkamera, augmented reality, query pencarian bisa jadi hanya berupa citra, namun pencarian produk dengan menggunakan citra pada umumnya tidak diakomodasi di situs e-commerce. Dalam penelitian ini dikembangkan sistem meta search-engine yang menggunakan query berupa citra dan berbasiskan konten untuk menggabungkan hasil pencarian dari beberapa situs e-commerce. Citra query yang tidak diketahui namanya dibangkitkan tag atau kata kuncinya melalui Google reverse image search engine. Kata kunci ini kemudian diberikan ke masing-masing situs e-commerce untuk dilakukan pencarian. Fitur yang digunakan dalam pencocokan query dengan produk adalah fitur tekstual, color histogram bin, dan keberadaan citra objek yang dicari menggunakan SURF descriptor. Fitur-fitur ini digunakan untuk menentukan relevansi terhadap hasil penelusuran. Sistem ini dapat memberikan hasil yang baik dengan precision@20 dan recall hingga 1 dengan rata-rata precision@20 dan recall masing-masing sebesar 0,564 dan 0,608, namun juga bisa gagal dengan precision@20 dan recall sebesar 0. Hasil yang kurang baik ini dikarenakan tag yang dibangkitkan terlalu umum dan situs e-commerce-pun memberikan hasil yang umum juga

  9. Microbes, Minerals and Electrodes at the Sanford Underground Research Facility (SURF): Electrochemistry 4100 ft below the surface.

    Science.gov (United States)

    Rowe, A. R.; Abuyen, K.; Casar, C. P.; Osburn, M. R.; Kruger, B.; El-Naggar, M.; Amend, J.

    2017-12-01

    Little is known about the importance of mineral oxidation processes in subsurface environments. This stems, in part from our limited insight into the biochemistry of many of these metabolisms, especially where redox interactions with solid surfaces is concerned. To this aim, we have been developing electrochemical cultivation techniques, to target enrichment and isolation of microbes capable of oxidative extracellular electron transfer (oxEET)—transfer of electrons from the exterior of the cell to the interior. Our previous worked focused on marine sediments; using an electrode poised at a given redox potential to isolate mineral-oxidizing microbes. Electrode oxidizing microbes isolated from these enrichments belong to the genera Thioclava, Marinobacter, Halomonas, Idiomarina, Thalassospira, and Pseudamonas; organisms commonly detected in marine and deep sea sediments but not generally associated with mineral, sulfur and/or iron oxidation. At the Sanford Underground Research Facility (SURF) in Leed, South Dakota, we have been utilizing similar electrocultivation techniques to understand: 1) the potential for mineral oxidation by subsurface microbes, 2) their selective colonization on mineral vs. electrode surfaces, as well as 3) the community composition of microbes capable of these metabolic interactions. An electrochemical and mineral enrichment scheme was designed and installed into a sulfidic groundwater flow, located at the 4100 ft level of the former gold mine. The communities enriched on electrodes (graphite and indium tin oxide coated glass) and minerals (sulfur, pyrite, and schists from the location) were compared to the long-term ground water microbial community observed. Ultimately, these observations will help inform the potential activity of a lithotrophic microbes in situ and will in turn guide our culturing efforts.

  10. Estudio y diseño de una quilla con propela incorporada para la propulsión de una tabla de surf

    OpenAIRE

    Corpas Amills, Andreu

    2018-01-01

    El treball desenvolupat en aquest document recull totes les etapes contingudes en la fase de disseny d’una quilla amb propela incorporada. La finalitat d’aquest disseny és proporcionar una impuls extra al surfista mantenint així l’essència del surf; les remades. El principal objectiu del treball doncs, consisteix en reduir l’esforç de la remada d’un surfista. Per fer-ho possible, cal realitzar el disseny d’un prototip de quilla amb les millors prestacions hidrodinàmiques possibles a més a ...

  11. The Influence of the Internet Surfing on the Reading Culture of Secondary School Teachers: A Case Study of Newspaper Readership in Kigumo Sub County, Kenya

    OpenAIRE

    Margaret Njoki Ngugi; Hellen k. Mberia

    2014-01-01

    Reading in the 21st century networked society is no longer confined to the print reading. The scope of the reading has extended to the Internet sources that changed the traditional reading culture of the readers. The present study was conducted to identify the impact of the Internet surfing on the reading culture of secondary school teachers in Kigumo Sub County. The objectives of the study were to find out the influence of the internet on the reading culture of secondary school teachers in K...

  12. Particle size distributions, size concentration relationships, and adherence to hands of selected geologic media derived from mining, smelting, and quarrying activities

    Energy Technology Data Exchange (ETDEWEB)

    Bergstrom, Carolyn; Shirai, Jeffry; Kissel, John, E-mail: jkissel@uw.edu

    2011-09-15

    Hand-to-mouth activity, especially in children, is a potentially significant pathway of exposure to soil contaminants. Hand-mouthing behavior is of particular concern in areas impacted by mining, smelting, and quarrying activities as these activities may lead to elevated levels of heavy metals in soil. In order to estimate potential exposures to contaminated geologic media attributable to hand-to-mouth contact, it is useful to characterize adherence of those media to skin, as contaminant concentrations in adhered media may differ greatly from unfractionated, whole media concentrations. Such an investigation has been undertaken to aid estimation of exposures to arsenic, cadmium, lead, and zinc in nine different geologic media collected in the Pacific Northwest region of the United States. After establishing the particle size distribution of each medium (fractions < 63 {mu}m, 63-150 {mu}m, 150-250 {mu}m, and 250 {mu}m-2 mm were determined) and target elemental concentrations within each particle size fraction, an active handling protocol involving six volunteers was conducted. Wet media always adhered to a greater extent than dry media and adhered media generally had higher elemental concentrations than bulk media. Regression analyses suggest smaller particle fractions may have higher elemental concentrations. Results of application of a maximum likelihood estimation technique generally indicate that handling of dry media leads to preferential adherence of smaller particle sizes, while handling of wet media does not. Because adhered material can differ greatly in particle size distribution from that found in bulk material, use of bulk concentrations in exposure calculations may lead to poor estimation of actual exposures. Since lead has historically been a metal of particular concern, EPA's Integrated Exposure Uptake Biokinetic (IEUBK) Model was used to examine the potential consequences of evaluating ingestion of the selected media assuming concentrations in

  13. Assessment of environmental and health risks in former polymetallic ore mining and smelting area, Slovakia: Spatial distribution and accumulation of mercury in four different ecosystems.

    Science.gov (United States)

    Árvay, Július; Demková, Lenka; Hauptvogl, Martin; Michalko, Miloslav; Bajčan, Daniel; Stanovič, Radovan; Tomáš, Ján; Hrstková, Miroslava; Trebichalský, Pavol

    2017-10-01

    Former long-term mining and smelting of pollymetallic ores in the Middle Spiš area caused a serious contamination problem of the environment with heavy metals and metalloids, especially mercury (Hg). Several studies have reported concentration of Hg in the area but this paper provides first detailed characterization of Hg contamination of different environmental components in agricultural, forest, grassland and urban ecosystems. The ecosystems are in different distances from emission sources - former mercury and copper smelting plants in NE Slovakia. Total Hg content was studied in soil/substrate samples (n = 234) and characteristic biological samples (Athyrium filix-femina (L.) Roth, Macrolepiota procera (Scop.) Singer, Boletus edulis Bull., Cyanoboletus pulverulentus (Opat.) Gelardi, Vizzini & Simonini, Triticum aestivum (L.), Poa pratensis (L.)) (n = 234) collected in the above-mentioned ecosystems. The level of contamination and environmental risks were assessed by contamination factor (C f ), index of geoaccumulation (I geo ) and potential environmental risk index (PER). To determine the level of transition of Hg from abiotic to biotic environment, bioconcentration factor (BCF) was used. To determine a health risk resulting from regular and long-term consumption of the locally available species, the results of the Hg content were compared with the Provisional Tolerable Weekly Intake (PTWI) for Hg defined by World Health Organization. The results suggest that almost 63% of the area belong to the very high risk category and 80% of the sampling sites shown very high contamination factor. Geoaccumulation index showed that almost 30% of the area is very strongly contaminated and only 8% is not contaminated with Hg. Spearman's correlation relationship confirmed that the values of PER, BCF, C f and I geo decreased with an increasing distance from the pollution source. The percentage of contribution to PTWI ranged between 5.76-69.0% for adults and 11.5-138% for

  14. Heavy metal contamination of arable soil and corn plant in the vicinity of a zinc smelting factory and stabilization by liming.

    Science.gov (United States)

    Hong, Chang Oh; Gutierrez, Jessie; Yun, Sung Wook; Lee, Yong Bok; Yu, Chan; Kim, Pil Joo

    2009-02-01

    The heavy metal contamination in soils and cultivated corn plants affected by zinc smelting activities in the vicinity of a zinc smelting factory in Korea was studied. Soils and corn plants were sampled at the harvesting stage and analyzed for cadmium (Cd) and zinc (Zn) concentration, as well as Cd and Zn fraction and other chemical properties of soils. Cd and Zn were highly accumulated in the surface soils (0-20 cm), at levels higher than the Korean warning criteria (Cd, 1.5; Zn, 300 mg kg(-1)), with corresponding mean values of 1.7 and 407 mg kg(-1), respectively, but these metals decreased significantly with increasing soil depth and distance from the factory, implying that contaminants may come from the factory through aerosol dynamics (Hong et al., Kor J Environ Agr 26(3):204-209, 2007a; Environ Contam Toxicol 52:496-502, 2007b) and not from geological sources. The leaf part had higher Cd and Zn concentrations, with values of 9.5 and 1733 mg kg(-1), compared to the stem (1.6 and 547 mg kg(-1)) and grain (0.18 and 61 mg kg(-1)) parts, respectively. Cd and Zn were higher in the oxidizable fraction, at 38.5% and 46.9% of the total Cd (2.6 mg kg(-1)) and Zn (407 mg kg(-1)), but the exchangeable + acidic fraction of Cd and Zn as the bioavailable phases was low, 0.2 and 50 mg kg(-1), respectively. To study the reduction of plant Cd and Zn uptake by liming, radish (Raphanus sativa L.) was cultivated in one representative field among the sites investigated, and Ca(OH)(2) was applied at rates of 0, 2, 4, and 8 mg ha(-1). Plant Cd and Zn concentrations and NH(4)OAc extractable Cd and Zn concentrations of soil decreased significantly with increasing Ca(OH)(2) rate, since it markedly increases the cation exchange capacity of soil induced by increased pH. As a result, liming in this kind of soil could be an effective countermeasure in reducing the phytoextractability of Cd and Zn.

  15. Assessment of primary production in a eutrophic lake from carbon and nitrogen isotope ratios of a carnivorous fish

    International Nuclear Information System (INIS)

    Yoshioka, Takahito

    1991-01-01

    The carbon and nitrogen isotope ratios of Hypomesus transpacificus (a pond smelt) in a eutrophic lake, Lake Suwa, were measured from April to September in 1986 and 1987. The differences in the isotope ratios between these two years were observed. The stable isotopes were transferred from phytoplankton to zooplankton and pond smelt, associated with organic matters. Therefore, the difference in the isotope ratios in two years seemed to reflect the differences of the proceeding of primary production. It was suggested that the carbon and nitrogen isotope ratios of animal, whose trophic level is far from primary producer, can be the qualitative indicators for assessing the primary production in a lake ecosystem. (author)

  16. The utility of Pinus sylvestris L. in dendrochemical investigations: Pollution impact of lead mining and smelting in Darley Dale, Derbyshire, UK

    International Nuclear Information System (INIS)

    Lageard, J.G.A.; Howell, J.A.; Rothwell, J.J.; Drew, I.B.

    2008-01-01

    This research investigates atmospheric pollution from an isolated and increasingly productive lead-smelting site by examining the dendrochemistry of Pinus sylvestris growing in the local environment and at control sites. Tree increment cores and soil in the rooting environment were analysed for lead content. Inter-site comparisons of lead-in-soil suggest that contamination of the soil may be a less important pathway for lead inclusion within wood than pathways via bark or needles. Levels of lead-in-wood (up to 38 mg kg -1 ) are at the upper end of those previously reported. There is evidence of radial translocation of lead towards the heartwood and variability in intra-site dendrochemical records. Mean site lead-in-wood records can however be related to a well-documented pollution chronology and also suggest the importance of local topography in the dispersal and deposition of particulate lead. This study demonstrates that P. sylvestris can be used to estimate the scale and timing of past pollution episodes in similar environmental contexts to those investigated at Darley Dale, where precisely dated pollution chronologies are lacking. - Mean site dendrochemical records for Pinus sylvestris can be used to estimate the general scale and timing of atmospheric pollution episodes

  17. A guidance manual for estimating greenhouse gas emissions from fuel combustion and process-related sources for primary base metals smelting and refining

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-03-01

    This technical guidance manual is a useful resource for helping the metals industry compile inventories of its greenhouse gas (GHG) emissions. The guidance is consistent with Canada's national GHG accounting methodologies. It provides information to smelters and refiners of base metals on how to estimate their GHG emissions from fuel combustion and specific process-related activities. The base metals group in this manual included copper, nickel, lead, zinc, and cobalt. Fuel combustion includes all stationary combustion activities for generating heat or work, and includes waste incineration if the waste heat is used for energy. It also includes mobile fuel combustion activities such as on-site transportation of raw materials from one process to another. Guidance is provided for carbon dioxide (CO{sub 2}), methane (CH{sub 4}) and nitrous oxide (N{sub 2}O). Process-related activities include specific industrial processes that contribute to GHG emissions. For base metal smelting, this includes CO{sub 2} emissions from use of carbonate reagents, use of reducing agents, electrode consumption, and hydrofluorocarbons (HFC) emissions from use in refrigeration systems. This document also included sections on quality assurance; aspects of uncertainty assessment; verification; and, reporting of emissions information. refs., tabs., figs.

  18. Joint study on smelting reduction. ; Results of elementary study and future studies. Yoyu kangen kyodo kenkyu; Yoso kenkyu no seika to kongo no torikume

    Energy Technology Data Exchange (ETDEWEB)

    1991-03-01

    The paper outlines results of elementary study on the coal direct-use iron-making process and how to tackle with it in future. In the process coal and iron ores are used directly without prior treatments like coking and briquetting. The process is composed of three elements: smelting reducing furnace, preliminary reduction fluidized bed, gas reforming furnace. Making mathematical models as a means of study of the process, material balance and heat balance are calculated. Operational unit requirements are estimated, changing them in the range of 20-60% of the post combustion based on three fundamental processes each of which is composed of one or a combination of the three elements. The total cost is also trially calculated, estimating fixed cost including installation cost, etc. With no big differences in the iron-melting cost excluding by-products in each process, the cost may be reduced by 5-10% of that in the blast furnace process. The elementary study has continued almost satisfactorily and attained the expected target, though there still remain some problems. In 1990 the study started of a pilot plant with a 500t/day capacity. 12 figs.

  19. The utility of Pinus sylvestris L. in dendrochemical investigations: pollution impact of lead mining and smelting in Darley Dale, Derbyshire, UK.

    Science.gov (United States)

    Lageard, J G A; Howell, J A; Rothwell, J J; Drew, I B

    2008-05-01

    This research investigates atmospheric pollution from an isolated and increasingly productive lead-smelting site by examining the dendrochemistry of Pinus sylvestris growing in the local environment and at control sites. Tree increment cores and soil in the rooting environment were analysed for lead content. Inter-site comparisons of lead-in-soil suggest that contamination of the soil may be a less important pathway for lead inclusion within wood than pathways via bark or needles. Levels of lead-in-wood (up to 38mgkg(-1)) are at the upper end of those previously reported. There is evidence of radial translocation of lead towards the heartwood and variability in intra-site dendrochemical records. Mean site lead-in-wood records can however be related to a well-documented pollution chronology and also suggest the importance of local topography in the dispersal and deposition of particulate lead. This study demonstrates that P. sylvestris can be used to estimate the scale and timing of past pollution episodes in similar environmental contexts to those investigated at Darley Dale, where precisely dated pollution chronologies are lacking.

  20. Polycyclic aromatic hydrocarbons in ambient air, surface soil and wheat grain near a large steel-smelting manufacturer in northern China.

    Science.gov (United States)

    Liu, Weijian; Wang, Yilong; Chen, Yuanchen; Tao, Shu; Liu, Wenxin

    2017-07-01

    The total concentrations and component profiles of polycyclic aromatic hydrocarbons (PAHs) in ambient air, surface soil and wheat grain collected from wheat fields near a large steel-smelting manufacturer in Northern China were determined. Based on the specific isomeric ratios of paired species in ambient air, principle component analysis and multivariate linear regression, the main emission source of local PAHs was identified as a mixture of industrial and domestic coal combustion, biomass burning and traffic exhaust. The total organic carbon (TOC) fraction was considerably correlated with the total and individual PAH concentrations in surface soil. The total concentrations of PAHs in wheat grain were relatively low, with dominant low molecular weight constituents, and the compositional profile was more similar to that in ambient air than in topsoil. Combined with more significant results from partial correlation and linear regression models, the contribution from air PAHs to grain PAHs may be greater than that from soil PAHs. Copyright © 2016. Published by Elsevier B.V.

  1. Lead, Zn, and Cd in slags, stream sediments, and soils in an abandoned Zn smelting region, southwest of China, and Pb and S isotopes as source tracers

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yuangen; Li, Sun; Bi, Xiangyang; Wu, Pan; Liu, Taozhe; Li, Feili; Liu, Congqiang [Chinese Academy of Sciences, Guiyang City (China). Inst. of Geochemistry

    2010-12-15

    Smelting activity produced tons of slags with large quantities of highly toxic metals, resulting in contamination in adjacent soils and sediments as well. This study investigated the fractionation and sources of metals Pb, Zn, and Cd in polluted soils and sediments in a region with once prosperous Zn smelting activities in southwestern China. Soils with varying land uses were of a special concern due to their connection to the food chain. Obtained data would offer a valuable reference to the development of land-use management strategy in this region. In total, 130 soils and 22 stream sediments were sampled in the studied region. After air-dried and passed through a 2 mm sieve, soils and sediments were subjected to a three-step sequential extraction for the fractionation of Pb, Zn, and Cd. Besides, 66 slags were sampled, and acid-digested for the determination of total Pb, Zn, and Cd. Soils/sediments with extremely high Pb, Zn, and Cd concentrations were selected for observation and analysis using a scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. Stable lead and sulphur isotope techniques were applied for source tracing of metals in soils and sediments. Data were pooled for analysis of variance together with a post-hoc multiple comparison procedure. High concentrations of Pb ({proportional_to}46,219 mg kg{sup -1} with medians of 846 mg kg{sup -1} in soil, 7,415 mg kg{sup -1} in sediment, and 8,543 mg kg{sup -1} in slag), Zn ({proportional_to}57, 178 mg kg{sup -1} with medians of 1,085 mg kg{sup -1} in soil, 15,678 mg kg{sup -1} in sediment, and 14,548 mg kg{sup -1} in slag), and Cd ({proportional_to}312 mg kg{sup -1} with medians of 29.6 mg kg{sup -1} in soil, 47.1 mg kg{sup -1} in sediment, and 47.9 mg kg{sup -1} in slag) were measured. Soils with no cultivation had greater concentrations of Pb (16,686 mg kg{sup -1} in median), Zn (13,587 mg kg{sup -1} in median), and Cd (44.1 mg kg{sup -1} in median) than those with cultivation. Al

  2. The use of lichens in post-smelting dumps reclamation - preliminary results of experimental cultivation of selected species on slag substrate

    Science.gov (United States)

    Rola, Kaja; Osyczka, Piotr

    2017-11-01

    Conventional reclamation interventions of post-smelting slag dumps being undertaken so far either failed or produced poor results. Certain lichens, especially of the genus Cladonia, are known as effective colonisers of bare ground in anthropogenic habitats. The paper presents preliminary results of the experiment aimed at the evaluation of lichen usefulness in reclamation interventions. The cultivation in vivo involving transplantation of lichens directly on slag substrate was established in 2015. Five species, i.e. Cladonia rei, C. cariosa, C. pyxidata, C. subulata, C. macilenta, were transplanted into 32 cuvettes filled with sterilised slag substrate. The sample weight of 2 and 6 g were used and half of cuvettes were regularly supplied with 2% malt solution. The first important symptoms at the present stage of the experiment are as follow: the growth of thalli has appeared only in the case of first three species; C. rei shows the most effective development; cuvettes with 6 g sample weight are characterized by higher coverage of fresh lichen thalli; lichen biomass are visually higher in cuvettes treated with malt solution. The results give us reason to believe that lichens could be successfully used as an alternative element during planning of slag dumps reclamation in the future.

  3. Lead Contamination and Source Characterization in Soils Around a Lead-Zinc Smelting Plant in a Near-Urban Environment in Baoji, China.

    Science.gov (United States)

    Deng, Wenbo; Li, Xuxiang; An, Zhisheng; Yang, Liu

    2016-11-01

    Economic reforms in China since 1978 have promoted nationwide socioeconomic advancement but led to a considerable amount of environmental pollution. The distribution and sources of Pb in a typical peri-urban industrial part of Baoji, China, were assessed by determining the Pb contents and isotopic compositions in 52 topsoil samples from the study area. The topsoil samples were polluted averagely with 40.88 mg Pb kg -1 , was 1.86 times higher than the Pb content of local background soil (22.04 mg kg -1 ). Pb isotopic compositions were determined by analyzing samples prepared using total digestion and acid extraction methods. Radiogenic isotopes contributed more to the Pb concentrations in the acid extracts than in the total digests. This was shown by the 207/206 Pb and 208/206 Pb ratios, which were 0.845-0.88 and 2.088-2.128, respectively, in the acid extracts and 0.841-0.875 and 2.086-2.125, respectively, in the total digests. This indicates that anthropogenic sources of Pb could be identified more sensitively in acid extracts than in total digests. The Pb isotope ratios showed that burning coal and smelting ore are the predominant anthropogenic sources of Pb in the study area, i.e., a lead-zinc smelter and a coking plant are major sources of Pb in the study area.

  4. The use of lichens in post-smelting dumps reclamation – preliminary results of experimental cultivation of selected species on slag substrate

    Directory of Open Access Journals (Sweden)

    Rola Kaja

    2017-01-01

    Full Text Available Conventional reclamation interventions of post-smelting slag dumps being undertaken so far either failed or produced poor results. Certain lichens, especially of the genus Cladonia, are known as effective colonisers of bare ground in anthropogenic habitats. The paper presents preliminary results of the experiment aimed at the evaluation of lichen usefulness in reclamation interventions. The cultivation in vivo involving transplantation of lichens directly on slag substrate was established in 2015. Five species, i.e. Cladonia rei, C. cariosa, C. pyxidata, C. subulata, C. macilenta, were transplanted into 32 cuvettes filled with sterilised slag substrate. The sample weight of 2 and 6 g were used and half of cuvettes were regularly supplied with 2% malt solution. The first important symptoms at the present stage of the experiment are as follow: the growth of thalli has appeared only in the case of first three species; C. rei shows the most effective development; cuvettes with 6 g sample weight are characterized by higher coverage of fresh lichen thalli; lichen biomass are visually higher in cuvettes treated with malt solution. The results give us reason to believe that lichens could be successfully used as an alternative element during planning of slag dumps reclamation in the future.

  5. Observations of wave-induced pore pressure gradients and bed level response on a surf zone sandbar

    Science.gov (United States)

    Anderson, Dylan; Cox, Dan; Mieras, Ryan; Puleo, Jack A.; Hsu, Tian-Jian

    2017-06-01

    Horizontal and vertical pressure gradients may be important physical mechanisms contributing to onshore sediment transport beneath steep, near-breaking waves in the surf zone. A barred beach was constructed in a large-scale laboratory wave flume with a fixed profile containing a mobile sediment layer on the crest of the sandbar. Horizontal and vertical pore pressure gradients were obtained by finite differences of measurements from an array of pressure transducers buried within the upper several centimeters of the bed. Colocated observations of erosion depth were made during asymmetric wave trials with wave heights between 0.10 and 0.98 m, consistently resulting in onshore sheet flow sediment transport. The pore pressure gradient vector within the bed exhibited temporal rotations during each wave cycle, directed predominantly upward under the trough and then rapidly rotating onshore and downward as the wavefront passed. The magnitude of the pore pressure gradient during each phase of rotation was correlated with local wave steepness and relative depth. Momentary bed failures as deep as 20 grain diameters were coincident with sharp increases in the onshore-directed pore pressure gradients, but occurred at horizontal pressure gradients less than theoretical critical values for initiation of the motion for compact beds. An expression combining the effects of both horizontal and vertical pore pressure gradients with bed shear stress and soil stability is used to determine that failure of the bed is initiated at nonnegligible values of both forces.type="synopsis">type="main">Plain Language SummaryThe pressure gradient present within the seabed beneath breaking waves may be an important physical mechanism transporting sediment. A large-scale laboratory was used to replicate realistic surfzone conditions in controlled tests, allowing for horizontal and vertical pressure gradient magnitudes and the resulting sediment bed response to be observed with precise instruments

  6. Surfing a Standing Wave

    Science.gov (United States)

    de Campos Valadares, Eduardo; Alves, Esdras Garcia

    2005-05-01

    Local "reversal of gravity" can be simulated with an inverted pendulum whose pivot is made to oscillate vertically. A beautiful demonstration of this surprising effect can be found in Ref. 1. In this case, the pendulum is a piece of plastic straw and its pivot pin is fixed at the end of a plastic ruler that is made to oscillate vertically by a small eccentric motor. A theoretical treatment of this inverted pendulum may be found in Ref. 2.

  7. Surf Aces Resurfaced

    DEFF Research Database (Denmark)

    Carter, Dale

    2013-01-01

    of the commercial music industry prompted group members to resist perceived threats to their established profile. Yet in the longer term (and ironically in the name of commercial survival) The Beach Boys began selectively to adopt innovations they had previously shunned. Shorn of its more controversial associations......The rise of the American counter-culture between the early- to mid-1960s and early- to mid-1970s was closely associated with the growth of environmentalism. This article explores how both informed popular music, a form of expression which during these years became not only a prominent form...... 1967, the group’s leader Brian Wilson and lyricist Van Dyke Parks collaborated on a collection of songs embodying such progressive thinking, even though the music of The Beach Boys had previously shown no such ambitions. In the short term their efforts foundered as the risk-averse logic...

  8. MindSurf: a pilot study to assess the usability and acceptability of a smartphone app designed to promote contentment, wellbeing, and goal achievement.

    Science.gov (United States)

    Carey, Timothy A; Haviland, Jennifer; Tai, Sara J; Vanags, Thea; Mansell, Warren

    2016-12-12

    The Method of Levels (MOL) is a transdiagnostic cognitive therapy that promotes contentment, wellbeing, and goal achievement through the resolution of internal conflicts underlying psychological distress. MOL, based on Perceptual Control Theory (PCT), was developed in routine clinical practice and has been used effectively across different health services by different practitioners. Access to MOL-style questions through a smartphone app could, potentially, help both the general public maintain robust mental health, and also be a useful adjunct to therapy for clinical populations. The app is called MindSurf because of its focus on helping people explore their thinking. Prior to developing the app and using it with different populations it was necessary to determine whether such an idea would be usable for and acceptable to potential app users. Therefore, a pilot study was conducted with a non-clinical sample to assess the usability and acceptability of the app including monitoring whether the questions delivered in this way were associated with any adverse events. A pilot study using quantitative as well as qualitative methods and incorporating a repeated measures, A-B design was conducted. The 23 participants were healthy adult volunteers who were all either undergraduate students, postgraduate students, or staff of the University of Manchester. They received MOL-style questions on their mobile phones over a 1-week period. Qualitative results were encouraging and indicated that the format and style of questioning were acceptable to participants and did not lead to increased worry or concern. A one-way, repeated measures ANOVA indicated that there was a nonsignificant decrease in scores on the 21-item Depression, Anxiety, and Stress Scale (DASS21) over a 2 week period. The results of the pilot study justified development of MindSurf and further testing once it is available for use. A power analysis indicated that the pilot study was underpowered to detect

  9. Surf Zone Sediment Size Variation, Morphodynamics, and Hydrodynamics During Sea/Land Breeze and El-Norte Storm in Sisal, Yucatan, Mexico

    Science.gov (United States)

    Alrushaid, T.; Figlus, J.; Torres-Freyermuth, A.; Puleo, J. A.; Dellapenna, T. M.

    2016-02-01

    Coastlines around the world are under ever-increasing pressure due to population trends, commerce, and geophysical processes like tropical storms and erosion. This multi-institutional field campaign was conducted to improve our understanding of complex nearshore processes under varying forcing conditions on a microtidal, sandy beach located in Sisal, Yucatan from 3/27 to 4/12/2014. Hydrodynamics, morphodynamics, and textural variability were investigated during: (1) a cold front event (referred to as El-Norte); (2) land breeze (LB); and (3) sea breeze (SB). The instrumentation layout included three surf/swash zone cross-shore transects where water elevation, suspended sediment concentration, bed load, and current velocities were measured, as well as several offshore ADCP for hydrodynamic measurements. TKE, τb, ɛ and were estimated using the data obtained from surf zone ADV. In addition, Hs and Tsin the surf zone were computed using measurements from ADV pressure sensors, while a separate pressure transducer was used to obtain water free-surface elevation within the swash zone. During SB cycles the study area experienced wind velocities reaching up to 12ms-1, and 15ms-1 during El-Norte. Elevated wind stress during El-Norte resulted in Hs of 1.5m and 0.6m in water depths of 10m and 0.4m, respectively. Surface sediment grab samples during SB/LB cycles showed that the swash zone had a moderately well sorted distribution with a mean grain size of 0.5mm, while poor sorting and a mean grain size of 0.7mm were found during El-Norte. Additionally, measured bathymetry data showed evidence for offshore sandbar migration during strong offshore currents (0.4ms-1) during El-Norte, while onshore sandbar migration was evident during SB/LB periods (0.3ms-1 and 0.1ms-1, respectively). This study highlights how different weather forcing conditions affect hydrodynamics, morphodynamics, and textural variability on a sandy beach. Aside from furthering our knowledge on these complex

  10. Un hombre llamado pez: la historia de Duke Kahanamoku, el nadador más rápido del mundo y el padre del surf moderno. [A Man Called Fish: the History of Duke Kahanamoku, the fastest swimmer of the World and the father of modern surfing].

    Directory of Open Access Journals (Sweden)

    Daniel Esparza

    2014-10-01

    Full Text Available Duke Kahanamoku (1890-1968 forma parte del Salón de la Fama de la natación, y también del Salón de la Fama del surf. Es la única persona que tiene ese doble mérito. Las razones no son difíciles de entender: fue el nadador más rápido de entre los humanos hasta que llegó otro que no lo era: Tarzán, o mejor dicho, Johnny Weissmüller; y en cuanto al arte de montar las olas tuvo el mérito de expandir por otros mares y océanos esa actividad milenaria surgida en el Hawái arcaico hasta el punto de ser considerado por casi todos el padre del surf moderno. ¿Cuáles fueron sus éxitos en la natación? ¿Qué había de innovador en su técnica que le hizo el más rápido? ¿Cómo expandió el surf al mismo tiempo que realizaba exhibiciones de natación? ¿De qué energía carismática estaba dotado este hombre, que hasta el propio JFK en su visita a Honolulu en 1962 se saltó absolutamente todo el protocolo entre las autoridades norteamericanas para dirigirse directamente hacia él y saludarle efusivamente? He aquí su historia.

  11. Time-of-flight secondary ion mass spectrometry (ToF-SIMS)-based analysis and imaging of polyethylene microplastics formation during sea surf simulation.

    Science.gov (United States)

    Jungnickel, H; Pund, R; Tentschert, J; Reichardt, P; Laux, P; Harbach, H; Luch, A

    2016-09-01

    Plastic particles smaller than 5mm, so called microplastics have the capability to accumulate in rivers, lakes and the marine environment and therefore have begun to be considered in eco-toxicology and human health risk assessment. Environmental microplastic contaminants may originate from consumer products like body wash, tooth pastes and cosmetic products, but also from degradation of plastic waste; they represent a potential but unpredictable threat to aquatic organisms and possibly also to humans. We investigated exemplarily for polyethylene (PE), the most abundant constituent of microplastic particles in the environment, whether such fragments could be produced from larger pellets (2mm×6mm). So far only few analytical methods exist to identify microplastic particles smaller than 10μm, especially no imaging mass spectrometry technique. We used at first time-of-flight secondary ion mass spectrometry (ToF-SIMS) for analysis and imaging of small PE-microplastic particles directly in the model system Ottawa sand during exposure to sea surf simulation. As a prerequisite, a method for identification of PE was established by identification of characteristic ions for PE out of an analysis of grinded polymer samples. The method was applied onto Ottawa sand in order to investigate the influence of simulated environmental conditions on particle transformation. A severe degradation of the primary PE pellet surface, associated with the transformation of larger particles into smaller ones already after 14days of sea surf simulation, was observed. Within the subsequent period of 14days to 1month of exposure the number of detected smallest-sized particles increased significantly (50%) while the second smallest fraction increased even further to 350%. Results were verified using artificially degraded PE pellets and Ottawa sand. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Prospects of utilization of electron beam irradiation technology to augment control of SO2 and other emissions from Chilean copper smelting plants

    International Nuclear Information System (INIS)

    Villanueva, L.; Ahumada, L.; Ellison, W.; Chmielewski, A.G.; Zimek, Z.

    1998-01-01

    Analysis of potential utilization of applicable SO 2 -removal process for reduced-SO 2 -strength off-gases, including electron-beam irradiation, for incrementally improving overall abatement of SO 2 /SO 3 emissions from existing copper smelting facilities in Chile has been carried out. Off-gases are characterized by SO 2 content higher than 3,000 ppm, a complex chemical composition and highly oxidizing conditions, along with cyclical and fluctuating generation, reflecting relatively severe service. Laboratory tests with simulated high-SO 2 -strength process gas were performed at Polish Institute of Nuclear Chemistry and Technology. Test work proved the technical feasibility of removing SO 2 from ultra-high SO 2 content smelter gases by E-beam irradiation with ammonia injection. A laboratory unit with flow rate of 20 Nm 3 /h equipped with electron accelerator of 800 keV beam energy was used. Influence of different parameters on SO 2 removal efficiency, like temperature, dose, ammonia stoichiometry and water vapor content, has been established. Tests covered a high SO 2 content range, 2,000 to 10,000 ppm. A generic design has been deviced to address system arrangement, performance and control requirements. It encompasses upgrading of in-plant ventilation to the extent required by health standards, together with gas cleaning system based on EB Process. The arrangement of the facilities provides for gathering and treating off-gas from selected fugitive emission sources on a continuous basis, at the same time in-drafting a minimum amount of tramp air. An introductory dry dedusting stage uses activated coke injection in conjunction with a fabric filter to efficiently treat raw gas to remove heavy metals, including arsenic, along with particulate matter. Main conclusion of the two major stages of this work, i.e. experimental tests and engineering oriented studies, is that the EB Process is a simple and appropriate, cost-effective, chemical process that would, on a site

  13. Prospects of utilization of EB irradiation technology to augment control of SO2 and other emissions from Chilean copper smelting plants

    International Nuclear Information System (INIS)

    Villanueva, L.; Ahumada, L.; Ellison, W.; Chmielewski, A.G.; Zimek, Z.

    1997-01-01

    A technical study including testing and cost analysis for commercial use of selected processes has been conducted. Analysis, affirmation and evaluation of potential utilization of applicable SO 2 -removal process for off-gases, including electron-beam irradiation, for incrementally improving abatement of SO 2 /SO 3 emissions from existing copper smelting facilities in Chile has been carried out. Off-gases are characterized by SO 2 content higher than 3,000 ppm, a complex chemical composition and highly oxidizing conditions, along with cyclical and fluctuating generation. Laboratory tests with simulated high-SO 2 -content process were performed at Institute of Nuclear Chemistry and Technology. Test work proved the technical feasibility of removing SO 2 from (ultra-high SO 2 contents) gases by E-beam irradiation with ammonia injection. A laboratory unit with flow rate of 20 Nm 3 /h equiped with electron accelerator of 800 keV beam energy was used. Influence of different parameters on SO 2 removal efficiency, like temperature, irradiation dose, ammonia stoichiometry and water vapor content, has been established. Tests covered a high SO 2 content range, 2,000 to 10,000 ppm. A generic schematic design has been devised to system arrangement, performance and control requirements. It encompasses upgrading of in-plant ventilation to the extent required by health standards, together with gas cleaning system incorporating the EB Process. The arrangement of the facilities provides for gathering and treating off-gas from selected fugitive emission sources on a continuos basis, at the same time in-drafting a minimum amount of tramp air. An introductory dry dedusting stage, when required, uses condictioned activated carbon injection in conjunction with a fabric filter to efficiently treat raw gas and remove heavy metals, including arsenic, along with particulate matter. Main conclusion of stages of this work is that the EB Process is a simple and appropriate, cost

  14. Acidic leaching of potentially toxic metals cadmium, cobalt, chromium, copper, nickel, lead, and zinc from two Zn smelting slag materials incubated in an acidic soil.

    Science.gov (United States)

    Liu, Taoze; Li, Feili; Jin, Zhisheng; Yang, Yuangen

    2018-07-01

    A column leaching study, coupled with acid deposition simulation, was conducted to investigate the leaching of potentially toxic metals (PTM) from zinc smelting slag materials (SSM) after being incubated in an acid Alfisol for 120 days at room temperature. Two SSMs (SSM-A: acidic, 10 yrs exposure with moderate high PTM concentrations versus SSM-B: alkaline, 2 yrs exposure with extremely high PTM concentrations), were used for the incubation at 0.5, 1, 2.5, 5 wt% amendment ratios in triplicate. Five leaching events were conducted at day 1, 3, 7, 14, and 28, and the leaching of PTMs mainly occurred in the first three leaching events, with the highest PTM concentrations in leachate measured from 5 wt% SSM amendments. After leaching, 2.5, 12, 5.5, 14, 11, and 9 wt% of M3 extractable Pb, Zn, Cd, Co, Cr, and Ni could be released from 5 wt% SSM-A amended soils, being respectively 25, 12, 4, 2, 2, and 2 times more than those from 5 wt% SSM-B amended soils. In the leachates, the concentrations of PTMs were mostly affected by leachant pH and were closely correlated to the concentrations of Fe, Al, Ca, Mg and P with Cd, Pb, and Zn showing the most environmental concern. Visual MINTEQ 3.1 modeling suggested metallic ions and sulfate forms as the common chemical species of PTMs in the leachates; whereas, organic bound species showed importance for Cd, Pb, Cu, and Ni, and CdCl + was observed for Cd. Aluminum hydroxy, phosphate, and sulfate minerals prevailed as the saturated minerals, followed by chloropyromorphite (Pb 5 (PO 4 ) 3 Cl) and plumbogummite (PbAl 3 (PO 4 ) 2 (OH) 5 ·H 2 O) in the leachates. This study suggested that incubation of SSMs in acidic soil for a long term can enhance the release of PTMs as the forms of metallic ions and sulfate when subjected to acid deposition leaching. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Implementation of the vortex force formalism in the coupled ocean-atmosphere-wave-sediment transport (COAWST) modeling system for inner shelf and surf zone applications

    Science.gov (United States)

    Kumar, Nirnimesh; Voulgaris, George; Warner, John C.; Olabarrieta, Maitane

    2012-01-01

    The coupled ocean-atmosphere-wave-sediment transport modeling system (COAWST) enables simulations that integrate oceanic, atmospheric, wave and morphological processes in the coastal ocean. Within the modeling system, the three-dimensional ocean circulation module (ROMS) is coupled with the wave generation and propagation model (SWAN) to allow full integration of the effect of waves on circulation and vice versa. The existing wave-current coupling component utilizes a depth dependent radiation stress approach. In here we present a new approach that uses the vortex force formalism. The formulation adopted and the various parameterizations used in the model as well as their numerical implementation are presented in detail. The performance of the new system is examined through the presentation of four test cases. These include obliquely incident waves on a synthetic planar beach and a natural barred beach (DUCK' 94); normal incident waves on a nearshore barred morphology with rip channels; and wave-induced mean flows outside the surf zone at the Martha's Vineyard Coastal Observatory (MVCO).

  16. THE BENEFITS OF SURFING HUMOR ON INTERNET TO INCREASE ENGLISH COMPETENCE AND CROSS CULTURAL UNDERSTANDING OF STUDENTS IN ENGLISH DEPARTMENT OF UNNES

    Directory of Open Access Journals (Sweden)

    Farah Firgia Lutfi

    2017-12-01

    Full Text Available Surfing humor on internet has got a lot of negative responses although the doers claim that it is fun. This research is focusing on the humor which is using English as the main language. However, previous researches have confirmed that there are witty and social sides of humor. Those two sides are important foundations to learn English further. The present paper aims to spot beneficial effects of self -humor exposure from Internet towards English competence and cross cultural understanding of students in English Department of Semarang State University. The way to ‗get‘ a humor content is divided into two, humor comprehension and humor perception. Humor comprehension has cognitive benefits that increase English competence. Humor appreciation has sociological benefits to increase cross cultural understanding. Thus, we are comparing English ability and social behavior of students with different intensity of self-humor exposure. Data were collected through interview. Students with high intensity and interest to self-humor exposure showed relatively higher English competence and tolerance to different ideas. The explanation will give broader idea of how learning English through humor brings positive values. Further research about the effects of humor in studying English is needed.

  17. Opportunities for energy conservation detected in a diagnosis made for the smelting industry; Oportunidades de ahorro de energia detectadas en un diagnostico efectuado en la industria de la fundicion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Bautista, Rolando; Magana Castro, Rogelio [Fideicomiso de Apoyo al Programa de Ahorro de Energia del Sector Electrico (FIDE), Mexico, D. F. (Mexico)

    1994-12-31

    The smelting industry is one of the main industrial branches in the utilization of electric power at national level, for this reason an energy diagnosis was made in representative industries of this process in which excellent results were obtained regarding opportunity areas, with potentials ranging from 15% up to 40% of energy saving in relation to the energy consumption, with actions recoverable in less than 15 months. [Espanol] La industria de la fundicion es una de las principales ramas industriales en la utilizacion de la energia electrica a nivel nacional, por esta razon se realizo un diagnostico energetico en empresas representativas de este proceso y en las cuales se obtuvieron excelentes resultados en cuanto a areas de oportunidad, teniendo potenciales que van desde un 15% hasta un 40% de ahorro con relacion al consumo de energia, con medidas que se recuperan en menos de 15 meses.

  18. Opportunities for energy conservation detected in a diagnosis made for the smelting industry; Oportunidades de ahorro de energia detectadas en un diagnostico efectuado en la industria de la fundicion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Bautista, Rolando; Magana Castro, Rogelio [Fideicomiso de Apoyo al Programa de Ahorro de Energia del Sector Electrico (FIDE), Mexico, D. F. (Mexico)

    1993-12-31

    The smelting industry is one of the main industrial branches in the utilization of electric power at national level, for this reason an energy diagnosis was made in representative industries of this process in which excellent results were obtained regarding opportunity areas, with potentials ranging from 15% up to 40% of energy saving in relation to the energy consumption, with actions recoverable in less than 15 months. [Espanol] La industria de la fundicion es una de las principales ramas industriales en la utilizacion de la energia electrica a nivel nacional, por esta razon se realizo un diagnostico energetico en empresas representativas de este proceso y en las cuales se obtuvieron excelentes resultados en cuanto a areas de oportunidad, teniendo potenciales que van desde un 15% hasta un 40% de ahorro con relacion al consumo de energia, con medidas que se recuperan en menos de 15 meses.

  19. Fault detection-case: modelling of temperature control of smelt in a chemical recovery; Deteccao de defeitos via redes neurais: aplicacao no sistema de resfriamento das bicas de fundidos de uma caldeira de recuperacao

    Energy Technology Data Exchange (ETDEWEB)

    Martinelli, Sergio H.S. [Universidade Estadual de Maringa, PR (Brazil); Klabin Papeis Monte Alegre, Telemaco Borba, PR (Brazil); Neitzel, Ivo [Faculdade de Telemaco Borba, PR (Brazil); Universidade Estadual de Maringa, PR (Brazil); Vieira, Osvaldo [Universidade Estadual de Maringa, PR (Brazil); Klabin Papeis Monte Alegre, Telemaco Borba, PR (Brazil)

    2008-07-01

    This paper proposes a method for the detection of defects in the control systems components which was applied in the smelt spouts cooling system of a chemical recovery boiler. The almost static behavior of the system was modeled with neural networks. The comparison between the inferred variable by the model and the measurement in the process generated a residual vector. A second neural network, the classification type, was built to analyze the residue. The training process of this neural network was carried out with two types of data base, one of them where there was no defect (classified as non faulty data) and the other where there were defects in one of the process control system sensors. The generation of faulty data was carried out through defects simulation by neural model. Both neural networks were programmed on Excel software to make the continuous monitoring of the productive process possible. The process data feeding in the system was done though the Plant Information (PI) software. The rate of false alarm of process monitoring for two and half months was of 3%. Errors ranging from 2 to 15% were simulated at the manipulated variable of the control system to test the performance of the method. Within the range of 10% simulated errors the detection of defects rate was of 97% for the set of non trained standards. (author)

  20. Using 137Cs as a tool for the assessment and the management of erosion/sedimentation risks in view of the restoration of the Rainbow Smelt (Osmerus mordax) fish population in the Boyer River basin (Quebec, Canada)

    International Nuclear Information System (INIS)

    Bernard, C.; Laverdiere, M.R.

    2000-01-01

    The Boyer River (Quebec, Canada) drains a 217 km 2 watershed that is under cultivation at 60%. The last 2 km of the river bed has always been used as a spawning ground by Rainbow Smelts (Osmerus mordax). This fish population, which plays an important ecological role in the St. Lawrence River estuary, has dramatically declined over the last decades. Siltation and excessive algal growth in the spawning area were identified as the most probable causes of the fish population decline; suggesting that soil erosion, nutrient and sediment transport are major factors underlying the environmental problem. In this context, 137 Cs provides an effective tool for investigating the magnitude and spatial distribution of long-term soil redistribution taking place in the watershed. Sampling of cultivated fields, riverbanks, bottom sediments and forested sites were thus undertaken to help understand the erosive behaviour of the watershed. Results obtained so far suggest in-field erosion rates of up to 13 t ha -1 yr -1 with net outputs reaching 11 t ha -1 yr -1 . These results agree well with estimates obtained from the USLE. The 137 Cs data indicate that fields located in the upstream half of the basin produce smaller sediment loadings than those in the downstream portion, despite higher soil erodibilities and more frequent use for annual crops. They also suggest that more than 75% of the sediment deposited in the spawning area originates from cultivated fields, and less than 25% from streambanks. (author)

  1. EFECTO EN LA RESISTENCIA DE LAS ESCORIAS DE FUNDICIÓN DE COBRE COMO AGREGADO FINO EN EL COMPORTAMIENTO RESISTENTE DEL HORMIGÓN EFFECT OF SMELTING COPPER SLAG AS FINE AGGREGATE ON THE RESISTANT BEHAVIOR OF CONCRETE

    Directory of Open Access Journals (Sweden)

    Patricio Cendoya

    2009-04-01

    Full Text Available Las escorias de fundición de cobre son residuos industriales provenientes de la fundición del cobre las cuales procesadas en forma de granallas y sometidas a un proceso de molienda adquieren características similares a las de un árido fino. La presente investigación estudia la influencia que tiene su incorporación en el comportamiento mecánico a flexotracción y compresión en hormigones que emplean como árido fino una combinación de arenas del río Bío-Bío con proporciones de 25%, 40% y 50% en volumen de escorias de fundición de cobre. El árido fino resultante se utiliza en la confección de hormigones dosificados para relaciones de agua cemento de 0,45 y 0,52 asociadas a resistencias especificadas a la flexotracción de 3,6 y 4,3 MPa. Se mide la trabajabilidad en el hormigón fresco, la densidad, la carga de rotura por flexotracción y la carga de rotura por compresión en el hormigón endurecido comparando los resultados con un hormigón de referencia que no contiene escorias. Los resultados señalan que la docilidad de la mezcla se incrementa debido a la textura lisa de las escorias, se produce un aumento de la densidad del hormigón endurecido y las resistencias tanto a flexotracción como compresión se incrementan en función del contenido de escorias de fundición de cobre utilizado en la mezcla.Copper slag is a by product of the copper smelting industry. We took granulated copper slag and milled it until it acquired characteristics similar to those of a fine aggregate, which was then incorporated into concrete, in combination with Bio-Bio river sand in proportions of 25%, 40% and 50% by volume of copper slag. We then examined the impact of the different combinations on the mechanical behaviour to flexotraction and compression in the resulting concrete. Our specification was to produce concrete for water-cement ratios of 0,45 and 0,52 associated to breakage resistances to flexotraction of 3.6 and 4.3 MPa, respectively. We

  2. Review of Liquidus Surface and Phase Equilibria in the TiO2-SiO2-Al2O3-MgO-CaO Slag System at PO2 Applicable in Fluxed Titaniferous Magnetite Smelting

    Science.gov (United States)

    Goso, Xolisa; Nell, Johannes; Petersen, Jochen

    The current liquidus surface and phase equilibria established in air for fluxed titaniferous magnetite (titanomagnetite) slags conforming to a composition of 37.19% TiO2, 19.69% SiO2, 13.12% Al2O3, and 30.00% of various ratios of CaO+MgO were reviewed at applicable PO2 using FactSage simulation and phase composition of a real plant titanomagnetite slag. The testwork included the incorporation into FactSage of a private MgTi2O5-Al2TiO5 pseudobrookite solution model. The results of the investigation showed that the liquidus surface and Ti3+/ Ti4+ mass fraction ratio increased with decreasing the PO2, At low PO2, perovskite crystallizes as a primary phase at high CaO content. The spinel solution, i.e. (Mg)(Al,Ti)O4, generally crystallizes as the primary phase at high MgO contents, though it is replaced by MgTi2O5-Al2TiO5 solution at PO2 of 10-10 atm to 10-15 atm. An intermediate equilibrium phase diagram established at PO2 of 10-16 atm is proposed. This phase diagram does not show the observed primary phase crystallization competition, however, the phase composition of a real titanomagnetite slag produced by Evraz Highveld Steel and Vanadium Corporation in South Africa does show primary phase crystallization competition between (Mg)(Al,Ti)2O4 and MgTi2O5-Al2TiO5. Smelting involving such slags is likely conducted around the transition PO2, i.e. PO2 of about 10-16 atm. Complex modelling with MgTi2O5, Al2TiO5 and Ti3O5 end members and experiments are underway to verify and update the intermediate phase diagram.

  3. Co-treatment of flotation waste, neutralization sludge, and arsenic-containing gypsum sludge from copper smelting: solidification/stabilization of arsenic and heavy metals with minimal cement clinker.

    Science.gov (United States)

    Liu, De-Gang; Min, Xiao-Bo; Ke, Yong; Chai, Li-Yuan; Liang, Yan-Jie; Li, Yuan-Cheng; Yao, Li-Wei; Wang, Zhong-Bing

    2018-03-01

    Flotation waste of copper slag (FWCS), neutralization sludge (NS), and arsenic-containing gypsum sludge (GS), both of which are difficult to dispose of, are major solid wastes produced by the copper smelting. This study focused on the co-treatment of FWCS, NS, and GS for solidification/stabilization of arsenic and heavy metals with minimal cement clinker. Firstly, the preparation parameters of binder composed of FWCS, NS, and cement clinker were optimized to be FWCS dosage of 40%, NS dosage of 10%, cement clinker dosage of 50%, mill time of 1.5 h, and water-to-binder ratio of 0.25. On these conditions, the unconfined compressive strength (UCS) of the binder reached 43.24 MPa after hydration of 28 days. Then, the binder was used to solidify/stabilize the As-containing GS. When the mass ratio of binder-to-GS was 5:5, the UCS of matrix can reach 11.06 MPa after hydration of 28 days, meeting the required UCS level of MU10 brick in China. Moreover, arsenic and other heavy metals in FWCS, NS, and GS were effectively solidified or stabilized. The heavy metal concentrations in leachate were much lower than those in the limits of China standard leaching test (CSLT). Therefore, the matrices were potential to be used as bricks in some constructions. XRD analysis shows that the main hydration products of the matrix were portlandite and calcium silicate hydrate. These hydration products may play a significant role in the stabilization/solidification of arsenic and heavy metals.

  4. Aluminum low temperature smelting cell metal collection

    Science.gov (United States)

    Beck, Theodore R.; Brown, Craig W.

    2002-07-16

    A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte. The method comprises the steps of providing a molten salt electrolyte in an electrolytic cell having an anodic liner for containing the electrolyte, the liner having an anodic bottom and walls including at least one end wall extending upwardly from the anodic bottom, the anodic liner being substantially inert with respect to the molten electrolyte. A plurality of non-consumable anodes is provided and disposed vertically in the electrolyte. A plurality of cathodes is disposed vertically in the electrolyte in alternating relationship with the anodes. The anodes are electrically connected to the anodic liner. An electric current is passed through the anodic liner to the anodes, through the electrolyte to the cathodes, and aluminum is deposited on said cathodes. Oxygen bubbles are generated at the anodes and the anodic liner, the bubbles stirring the electrolyte. Molten aluminum is collected from the cathodes into a tubular member positioned underneath the cathodes. The tubular member is in liquid communication with each cathode to collect the molten aluminum therefrom while excluding electrolyte. Molten aluminum is delivered through the tubular member to a molten aluminum reservoir located substantially opposite the anodes and cathodes. The molten aluminum is collected from the cathodes and delivered to the reservoir while avoiding contact of the molten aluminum with the anodic bottom.

  5. Tempo de reação simples auditivo e visual em surfistas com diferentes níveis de habilidade: comparação entre atletas profissionais, amadores e praticantes Auditory and visual single reaction span in surfers with different ability levels: comparison of professional, amateur athletes and surf practitioners

    Directory of Open Access Journals (Sweden)

    César Augusto Otero Vaghetti

    2007-04-01

    Full Text Available O tempo de reação simples (TRS representa o nível de coordenação neuromuscular, no qual os estímulos visuais, auditivos ou táteis são decodificados pelo corpo através de diferentes processos físico-químicos e mecânicos. O objetivo desta pesquisa foi identificar os TRS auditivo e visual em surfistas profissionais, amadores e praticantes, verificar se existem diferenças estatísticas entre os grupos de surfistas e correlacionar os tempos de reação com a performance dos atletas. Participaram deste estudo 103 surfistas: 42 atletas profissionais do sexo masculino (brasileiros e estrangeiros, 11 atletas profissionais do sexo feminino, 25 atletas amadores universitários e 25 praticantes de surfe. A coleta de dados foi realizada nas praias onde aconteceram os respectivos eventos, WQS (World Qualifyng Series, etapa do circuito mundial, Superfsurf (etapa do campeonato brasileiro de surfe profissional, CCSU (etapa do circuito catarinense de surfe universitário. Foram utilizados como instrumentação um interruptor com uma tecla de sensibilidade de 0,8N, um LED para estímulo visual, duas caixas acústicas, com 315Hz de freqüência e 81dB de pressão sonora, para estímulo auditivo e um dispositivo eletrônico com a finalidade de gerar o sinal auditivo, visual e de sincronismo. A aquisição dos dados foi realizada utilizando o software SAD versão 32. Foram encontradas diferenças estatisticamente significativas para os TRS auditivo e visual entre os profissionais (masculinos versus praticantes, profissionais (femininos versus praticantes. Entre os amadores versus praticantes foram encontradas diferenças estatisticamente significativas apenas para o TRS visual, com TRS menores para os mais experientes. Uma correlação positiva foi encontrada para o TRS visual entre os profissionais (femininos versus no ranking.The reaction span RS (RTS represents the level of neuromuscular coordination in which the visual, auditory or touch stimuli are

  6. Modelling rhythmic morphology in the surf zone

    NARCIS (Netherlands)

    Klein, M.D.

    2006-01-01

    Coastal erosion is increasingly being prevented by the application of shoreface nourishments. Although they are applied successfully, their development and their impact on the coastal system is still difficult to predict. Especially the effects of shoreface nourishments on the already existing

  7. ImageSURF MOAB2 Image Example

    OpenAIRE

    O'Mara, Aidan R; Collins, Jessica M; King, Anna E; Vickers, James C; Kirkcaldie, Matthew T K

    2017-01-01

    A set of 2000x2000 confocal fluorescence images of MOAB2-labelled cortex from APPswe/PS1dE9 mouse models of Alzheimer's disease, sparsely annotated pixel labels and reference segmentation examples. Pixels are annotated as signal (red 0xFFFF0000) and background (blue 0xFF0000FF). Images were captured as stitched 12-bit greyscale single-plane images and cropped to size. Image acquisition was performed at 561nm excitation and 615nm emission wavelengths using a Perkin Elmer Ultraview VOX ima...

  8. Surfing the net for public health resources.

    Science.gov (United States)

    Angell, C; Hemingway, A; Hartwell, H

    2011-08-01

    To identify public health open educational resources (OER) available online, map the identified OER to The Public Health Skills and Career Framework (PHSCF), and triangulate these findings with public health practitioners. Systematic online search for public health OER. An online search was undertaken using a pre-defined set of search terms and inclusion/exclusion criteria. Public health OER were then mapped against the UK PHSCF. The findings of the search were discussed with public health specialists to determine whether or not they used these resources. A number of public health OER were identified, located on 42 websites from around the world. Mapping against the UK PHSCF demonstrated a lack of coverage in some areas of public health education. It was noted that many of the OER websites identified were not those generally used in practice, and those sites preferred by public health specialists were not identified by the online search. Public health OER are available from a number of providers, frequently universities and government organizations. However, these reflect a relatively small pool of original OER providers. Tagging of websites does not always identify their public health content. In addition, users of public health OER may not use search engines to identify resources but locate them using other means. Copyright © 2011 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  9. Transformation of Waves Across the Surf Zone.

    Science.gov (United States)

    1981-03-01

    Kuo is more realis- tic but still results in a sharp cut-off of the distribution at the breaking heights. 5. Goda Distribution Goda (1975) derived a...J.I., "Probabilities of Breaking Wave Characteris- tics ," Proc. 12th Coastal Engineering Conf., pp. 399- 412, 1970. Chakrabarty, S.K. and R.P. Cooley...Spring, MD 20910 21. Director 2 Instituto Oceanografico de la Armada Guayaquil, Ecuador 22. Director de Educacion de la Armada Comandancia General de

  10. Surf Wave Hydrodynamics in the Coastal Environment

    NARCIS (Netherlands)

    Salmon, J.E.

    2016-01-01

    Stochastic wave models play a central role in our present-day wave modelling capabilities. They are frequently used to compute wave statistics, to generate boundary conditions and to include wave effects in coupled model systems. Historically, such models were developed to predict the wave field

  11. Smooth Particle Hydrodynamics for Surf Zone Waves

    Science.gov (United States)

    2009-01-01

    2010.) The GPU-SPHysics code, initiated by Dr. Alexis Hérault at the Istituto Nazionale di Geofisica e Vulcanologia in Sicily, has been applied to... Geofisica e Vulcanologia, sezione di Catania, for the development of GPU-SPHysics. Drs. Hérault and Bilotta were in residence at JHU during January of

  12. Shotgun metagenomic data streams: surfing without fear

    Energy Technology Data Exchange (ETDEWEB)

    Berendzen, Joel R [Los Alamos National Laboratory

    2010-12-06

    Timely information about bio-threat prevalence, consequence, propagation, attribution, and mitigation is needed to support decision-making, both routinely and in a crisis. One DNA sequencer can stream 25 Gbp of information per day, but sampling strategies and analysis techniques are needed to turn raw sequencing power into actionable knowledge. Shotgun metagenomics can enable biosurveillance at the level of a single city, hospital, or airplane. Metagenomics characterizes viruses and bacteria from complex environments such as soil, air filters, or sewage. Unlike targeted-primer-based sequencing, shotgun methods are not blind to sequences that are truly novel, and they can measure absolute prevalence. Shotgun metagenomic sampling can be non-invasive, efficient, and inexpensive while being informative. We have developed analysis techniques for shotgun metagenomic sequencing that rely upon phylogenetic signature patterns. They work by indexing local sequence patterns in a manner similar to web search engines. Our methods are laptop-fast and favorable scaling properties ensure they will be sustainable as sequencing methods grow. We show examples of application to soil metagenomic samples.

  13. Job Surfing: Move On to Move Up.

    Science.gov (United States)

    Martin, Justin

    1997-01-01

    Looks at the process of switching jobs and changing careers. Discusses when to consider options and make the move as well as the need to be flexible and open minded. Provides a test for determining the chances of promotion and when to move on. (JOW)

  14. Surfing the web and parkinson's law.

    Science.gov (United States)

    Baldwin, F D

    1996-05-01

    The World Wide Web accounts for much of the popular interest in the Internet and offers a rich and variegated source of medical information. It's where you'll find online attractions ranging from "The Visible Human" to collections of lawyer jokes, as well as guides to clinical materials. Here's a basic introduction to the Web, its features, and its vocabulary.

  15. Ecomorphology and food habits of teleost fishes Trachinotus carolinus (Teleostei: Carangidae and Menticirrhus littoralis (Teleostei: Sciaenidae, inhabiting the surf zone off Niterói, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Luana Prestrelo Palmeira

    2010-01-01

    Full Text Available The ecomorphology and food habits of juvenile Trachinotus carolinus and Menticirrhus littoralis caught in the surf zone of sandy beaches in Niterói, RJ, were investigated between July 2006 and May 2007. These fish species differ morphologically, but present similarities in their diet composition suggest some slight overlapping in their diet. The importance of food items was assessed using Kawakami and Vazzoler's feeding index. Morphometric variables were recorded to correlate with the diet composition of the different size classes for each species. A total of 210 fishes (Trachinotus carolinus - 122, Menticirrhus littoralis - 88, ranging between 24.2 mm and 112 mm total length, were analyzed, but the stomachs of only 84.8% of them contained food. Trachinotus carolinus presented mysids, Polychaetes and Emerita spp. as the predominant items in their diet. Formicidae and Isopoda were the most important items for class I individuals, whereas mysids and Emerita spp. were important for classes II and III. Class I individuals also showed smaller sized prey (amphipods and isopods and clupeid fish larvae in their diet. Emerita spp. dominated the food items of Menticirrhus littoralis regardless of the size class. Polychaetes, the second most important item was better represented in class sizes II and III. The main morphometric variable correlated with such differences included mouth position and diameter of the eye.A ecomorfologia e os hábitos alimentares de juvenis de Trachinotus carolinus e Menticirrhus littoralis capturados na zona de arrebentação de praias arenosas em Niterói, RJ, foram investigados entre julho de 2006 e Maio de 2007. Ambas as espécies diferem morfologicamente, mas apresentam semelhanças em sua dieta, sugerindo uma possível sobreposição alimentar. A importância dos itens alimentares foi avaliada utilizando o índice alimentar de Kawakami e Vazzoler. Variáveis morfométricas foram correlacionadas à dieta observada para

  16. Synthesis of studies in the fall low-salinity zone of the San Francisco Estuary, September-December 2011

    Science.gov (United States)

    Brown, Larry R.; Baxter, Randall; Castillo, Gonzalo; Conrad, Louise; Culberson, Steven; Erickson, Gregg; Feyrer, Frederick; Fong, Stephanie; Gehrts, Karen; Grimaldo, Lenny; Herbold, Bruce; Kirsch, Joseph; Mueller-Solger, Anke; Slater, Steven B.; Sommer, Ted; Souza, Kelly; Van Nieuwenhuyse, Erwin

    2014-01-01

    In fall 2011, a large-scale investigation (fall low-salinity habitat investigation) was implemented by the Bureau of Reclamation in cooperation with the Interagency Ecological Program to explore hypotheses about the ecological role of low-salinity habitat in the San Francisco Estuary—specifically, hypotheses about the importance of fall low-salinity habitat to the biology of delta smelt Hypomesus transpacificus, a species endemic to the San Francisco Estuary and listed as threatened or endangered under federal and state endangered species legislation. The Interagency Ecological Program is a consortium of 10 agencies that work together to develop a better understanding of the ecology of the Estuary and the effects of the State Water Project and Federal Central Valley Project operations on the physical, chemical, and biological conditions of the San Francisco Estuary. The fall low-salinity habitat investigation constitutes one of the actions stipulated in the Reasonable and Prudent Alternative issued with the 2008 Biological Opinion of the U.S. Fish and Wildlife Service, which called for adaptive management of fall Sacramento-San Joaquin Delta outflow following “wet” and “above normal” water years to alleviate jeopardy to delta smelt and adverse modification of delta smelt critical habitat. The basic hypothesis of the adaptive management of fall low-salinity habitat is that greater outflows move the low-salinity zone (salinity 1–6), an important component of delta smelt habitat, westward and that moving the low-salinity zone westward of its position in the fall of recent years will benefit delta smelt, although the specific mechanisms providing such benefit are uncertain. An adaptive management plan was prepared to guide implementation of the adaptive management of fall low-salinity habitat and to reduce uncertainty. This report has three major objectives:

  17. Can't surf, won't surf: the digital divide in mental health.

    Science.gov (United States)

    Ennis, Liam; Rose, Diana; Denis, Mike; Pandit, Ninjeri; Wykes, Til

    2012-08-01

    New health information technology (HIT) increasingly plays a role in health care as technology becomes cheaper and more widespread. However, there is a danger that those who do not use or have access to technology will not benefit from HIT innovations, thus creating a "digital divide". To assess the extent to which mental health service users have access to, skills in using and appetite for various technologies. A cross-sectional survey was used to assess technology use and access patterns of 121 people from community mental health services. Data were analysed using logistic regression. Technology use and access were very similar to that of the general population with older individuals reporting less familiarity, access and confidence across a range of technologies. Black, minority and ethnic (BME) groups were more likely to access computers outside of their own homes than white individuals. Older participants experiencing psychosis indicated a desire to increase their computer use. The findings reported here contrast with recent evidence suggesting that those who do not engage with technology are "self-excluders". Furthermore, BME groups may need extra support regarding provision of technology in order to engage with HIT.

  18. Solar Surfing-Phase I and Solar Surfing - How Close to the Sun Can We Get?

    Science.gov (United States)

    Youngquist, Robert; Nurge, Mark; Williams, Bruce

    2017-01-01

    The NASA Innovative Advanced Concept (NIAC) program has been funding work at KSC on a novel coating that should allow a future spacecraft to come close to the Sun. The NIAC Symposium will be the last week of September and it is a requirement that the funded material be presented both orally and at a poster session. This DAA submission is requesting approval to go public with both the presentation and the poster.

  19. Coupled Downscaled Climate Models and Ecophysiological Metrics Forecast Habitat Compression for an Endangered Estuarine Fish.

    Directory of Open Access Journals (Sweden)

    Larry R Brown

    Full Text Available Climate change is driving rapid changes in environmental conditions and affecting population and species' persistence across spatial and temporal scales. Integrating climate change assessments into biological resource management, such as conserving endangered species, is a substantial challenge, partly due to a mismatch between global climate forecasts and local or regional conservation planning. Here, we demonstrate how outputs of global climate change models can be downscaled to the watershed scale, and then coupled with ecophysiological metrics to assess climate change effects on organisms of conservation concern. We employed models to estimate future water temperatures (2010-2099 under several climate change scenarios within the large heterogeneous San Francisco Estuary. We then assessed the warming effects on the endangered, endemic Delta Smelt, Hypomesus transpacificus, by integrating localized projected water temperatures with thermal sensitivity metrics (tolerance, spawning and maturation windows, and sublethal stress thresholds across life stages. Lethal temperatures occurred under several scenarios, but sublethal effects resulting from chronic stressful temperatures were more common across the estuary (median >60 days above threshold for >50% locations by the end of the century. Behavioral avoidance of such stressful temperatures would make a large portion of the potential range of Delta Smelt unavailable during the summer and fall. Since Delta Smelt are not likely to migrate to other estuaries, these changes are likely to result in substantial habitat compression. Additionally, the Delta Smelt maturation window was shortened by 18-85 days, revealing cumulative effects of stressful summer and fall temperatures with early initiation of spring spawning that may negatively impact fitness. Our findings highlight the value of integrating sublethal thresholds, life history, and in situ thermal heterogeneity into global change impact

  20. Coupled downscaled climate models and ecophysiological metrics forecast habitat compression for an endangered estuarine fish

    Science.gov (United States)

    Brown, Larry R.; Komoroske, Lisa M; Wagner, R Wayne; Morgan-King, Tara; May, Jason T.; Connon, Richard E; Fangue, Nann A.

    2016-01-01

    Climate change is driving rapid changes in environmental conditions and affecting population and species’ persistence across spatial and temporal scales. Integrating climate change assessments into biological resource management, such as conserving endangered species, is a substantial challenge, partly due to a mismatch between global climate forecasts and local or regional conservation planning. Here, we demonstrate how outputs of global climate change models can be downscaled to the watershed scale, and then coupled with ecophysiological metrics to assess climate change effects on organisms of conservation concern. We employed models to estimate future water temperatures (2010–2099) under several climate change scenarios within the large heterogeneous San Francisco Estuary. We then assessed the warming effects on the endangered, endemic Delta Smelt, Hypomesus transpacificus, by integrating localized projected water temperatures with thermal sensitivity metrics (tolerance, spawning and maturation windows, and sublethal stress thresholds) across life stages. Lethal temperatures occurred under several scenarios, but sublethal effects resulting from chronic stressful temperatures were more common across the estuary (median >60 days above threshold for >50% locations by the end of the century). Behavioral avoidance of such stressful temperatures would make a large portion of the potential range of Delta Smelt unavailable during the summer and fall. Since Delta Smelt are not likely to migrate to other estuaries, these changes are likely to result in substantial habitat compression. Additionally, the Delta Smelt maturation window was shortened by 18–85 days, revealing cumulative effects of stressful summer and fall temperatures with early initiation of spring spawning that may negatively impact fitness. Our findings highlight the value of integrating sublethal thresholds, life history, and in situ thermal heterogeneity into global change impact assessments. As

  1. Production of fish finger from sand smelt (Atherina boyeri, RISSO ...

    African Journals Online (AJOL)

    Administrator

    2011-05-23

    May 23, 2011 ... Departmant of Fishing and Fish Processing Technology, Faculty of Fisheries, University of Süleyman Demirel, 32500. Eğirdir, Isparta, Turkey. ... the consumption of food as “heat and eat” has become important. Food sector .... In many of the developed countries, the habits of nourish- ment are changing and ...

  2. State of the direct reduction and reduction smelting processes

    Directory of Open Access Journals (Sweden)

    Markotić A.

    2002-01-01

    Full Text Available For quite a long time efforts have been made to develop processes for producing iron i.e. steel without employing conventional procedures - from ore, coke, blast furnace, iron, electric arc furnace, converter to steel. The insufficient availability and the high price of the coking coals have forced many countries to research and adopt the non-coke-consuming reduction and metal manufacturing processes (non-coke metallurgy, direct reduction, direct processes. This paper represents a survey of the most relevant processes from this domain by the end of 2000, which display a constant increase in the modern process metallurgy.

  3. Chemical-mineralogical characterization of copper smelting flue dust

    Directory of Open Access Journals (Sweden)

    Eduardo Balladares

    2014-01-01

    Full Text Available En el procesamiento pirometalúrgico del cobre, hasta 10% de la carga alimentada a los hornos sale de estos en forma de polvo arrastrado por los gases conteniendo la mayor parte de las impurezas presentes en el mineral, así como cantidades significativas de cobre por lo que no pueden ser descartados como residuos industriales y debe tratarse para recuperar el cobre. La conceptualización de nuevos y mejores procesos requiere caracterizaciones de estos materiales más precisas. Se analizaron polvos provenientes de una caldera recuperadora de calor y de un precipitador electrostático, ambos de un horno de fusión instantánea. Las diferentes herramientas analíticas empleadas muestran que el cobre y el hierro se encuentran principalmente en fases solubles en agua tales como chalcantita. La fracción insoluble está formada mayoritariamente por hematita y magnetita, con probable presencia de delafosita. Parte del cobre detectada en la fracción insoluble se asocia al hierro en forma de espinela.

  4. The aluminum smelting process and innovative alternative technologies.

    Science.gov (United States)

    Kvande, Halvor; Drabløs, Per Arne

    2014-05-01

    The industrial aluminum production process is addressed. The purpose is to give a short but comprehensive description of the electrolysis cell technology, the raw materials used, and the health and safety relevance of the process. This article is based on a study of the extensive chemical and medical literature on primary aluminum production. At present, there are two main technological challenges for the process--to reduce energy consumption and to mitigate greenhouse gas emissions. A future step may be carbon dioxide gas capture and sequestration related to the electric power generation from fossil sources. Workers' health and safety have now become an integrated part of the aluminum business. Work-related injuries and illnesses are preventable, and the ultimate goal to eliminate accidents with lost-time injuries may hopefully be approached in the future.

  5. Changes on the nutritional compositions of the sand smelt (Atherina ...

    African Journals Online (AJOL)

    user

    2011-04-18

    Apr 18, 2011 ... ash and fat content and a decrease (P<0.05) in protein and moisture content were determined. In fatty .... cies as well as to present it to the market as an alternative food. ... in the glass jars again and sunflower oil was added (1:1 w/v). ... Determination of the fatty acid was performed by the use of gas.

  6. Electrolytic smelting of lunar rock for oxygen, iron, and silicon

    Science.gov (United States)

    Haskin, Larry A.; Colson, Russell O.; Lindstrom, David J.; Lewis, Robert H.; Semkow, Krystyna W.

    1992-01-01

    Preliminary studies of the electrochemical properties of silicate melts such as those available from heating of lunar mare soils indicate that conductivities are high enough for design of a practical electrolytic cell. The nature and kinetics of the electrode reactions, which involve reduction of Fe(++) and Si(IV) and oxidation of silicate anions as the primary, product-forming reactions, are also satisfactory. A survey of the efficiencies for production (amount of product for a given current) of O2, Fe(sup 0), and Si(sup 0) as functions of potential and of electrolyte composition indicate that conditions can be chosen to yield high production efficiencies. We also conclude that electronic conductivity does not occur to a significant extent. Based on these data, a cell with electrodes of 30 sq m in area operating between 1 and 5V with a current between 1.6 and 3.5(10)(exp 5) A for a mean power requirement of 0.54 MW and total energy use of approximately 13 MWhr per 24-hr day would produce 1 ton of O2, 0.81 ton of Fe(sup 0), 0.65 ton of Si(sup 0) (as Fe(sup 0)-Si(sup 0) alloy), and about 3.5 tons of silicate melt of altered composition per 24 hr. Adjustable distance between electrodes could offer flexibility with respect to feedstock and power source.

  7. The Aluminum Smelting Process and Innovative Alternative Technologies

    Science.gov (United States)

    Drabløs, Per Arne

    2014-01-01

    Objective: The industrial aluminum production process is addressed. The purpose is to give a short but comprehensive description of the electrolysis cell technology, the raw materials used, and the health and safety relevance of the process. Methods: This article is based on a study of the extensive chemical and medical literature on primary aluminum production. Results: At present, there are two main technological challenges for the process—to reduce energy consumption and to mitigate greenhouse gas emissions. A future step may be carbon dioxide gas capture and sequestration related to the electric power generation from fossil sources. Conclusions: Workers' health and safety have now become an integrated part of the aluminum business. Work-related injuries and illnesses are preventable, and the ultimate goal to eliminate accidents with lost-time injuries may hopefully be approached in the future. PMID:24806723

  8. Ecotoxicological damage from zinc smelting at Palmerton, Pennsylvania

    Science.gov (United States)

    Beyer, W. Nelson; Storm, Gerald L.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

    1995-01-01

    The two zinc smelters at Palmerton, PA emitted huge amounts of contaminants ( 260,000 t of Zn, 3,300 t of Cd, 6,800 t of Pb) to the air and severely damaged the forest on Blue Mountain. The high Zn concentrations in soil killed tree seedlings by inhibiting root elongation. The result was a forest with too few young trees. When natural stresses such as fire challenged the forest, the forest failed to regenerate, and the exposed soil eroded down the steep slopes. Tree species that could sprout were favored over those that developed from seeds. As a result of high zinc concentrations, the lichen and moss communities were depauperate for at least 20 km along Blue Mountain. The denuded areas are in the process of being reclaimed with the addition of a mixture of fly ash and sewage sludge, which is seeded with grasses tolerant to the harsh conditions. In preliminary experiments, the fly ash and sewage sludge mixture was stable, despite the steepness of the slopes of the reclaimed sites on Blue Mountain. Zinc emissions reduced the decomposition rate of plant material on Blue Mountain. The partially decomposed litter, in particular, accumulated on the surface of the mineral soil. The populations of both microorganisms and arthropods were greatly reduced in soils near the smelters. Samples of litter collected from sites spanning 30 km were toxic to woodlice, and Zn was shown to be the toxic factor. A white-tailed deer examined had a very high renal Zn concentration and an articular lesion in one of its hind legs that closely resembled the lesions reported in Zn-poisoned horses. Zinc concentrations were regulated in wildlife tissues and were not reliable indicators of exposure, except in extreme cases. Two songbirds, a shrew, and several rabbits contained Pb concentrations that were suggested to be toxic. Shrews and ground-feeding songbirds accumulated relatively high concentrations of Pb. Exposure to Pb seemed to be related to the amount of soil that an animal ingests. Some white-tailed deer and cottontails had renal Cd concentrations near 600 ppm w.w., which is associated with renal damage in other mammals. The accumulation of Cd was greatest in wildlife that lived longest. The destruction of the habitat for wildlife on Blue Mountain decreased wildlife populations. Populations of insectivorous birds, however, were depressed well beyond the area of obvious damage to the forest. Forest-floor salamanders were completely absent from study sites spanning 18 km along Blue Mountain. Actual reductions in wildlife populations were much greater than would have been predicted from habitat suitability models alone.

  9. Googling suicide: surfing for suicide information on the Internet.

    Science.gov (United States)

    Recupero, Patricia R; Harms, Samara E; Noble, Jeffrey M

    2008-06-01

    This study examined the types of resources a suicidal person might find through search engines on the Internet. We were especially interested in determining the accessibility of potentially harmful resources, such as prosuicide forums, as such resources have been implicated in completed suicides and are known to exist on the Web. Using 5 popular search engines (Google, Yahoo!, Ask.com, Lycos, and Dogpile) and 4 suicide-related search terms (suicide, how to commit suicide, suicide methods, and how to kill yourself), we collected quantitative and qualitative data about the search results. The searches were conducted in August and September 2006. Several coraters assigned codes and characterizations to the first 30 Web sites per search term combination (and "sponsored links" on those pages), which were then confirmed by consensus ratings. Search results were classified as being prosuicide, antisuicide, suicide-neutral, not a suicide site, or error (i.e., page would not load). Additional information was collected to further characterize the nature of the information on these Web sites. Suicide-neutral and anti-suicide pages occurred most frequently (of 373 unique Web pages, 115 were coded as suicide-neutral, and 109 were anti-suicide). While pro-suicide resources were less frequent (41 Web pages), they were nonetheless easily accessible. Detailed how-to instructions for unusual and lethal suicide methods were likewise easily located through the searches. Mental health professionals should ask patients about their Internet use. Depressed, suicidal, or potentially suicidal patients who use the Internet may be especially at risk. Clinicians may wish to assist patients in locating helpful, supportive resources online so that patients' Internet use may be more therapeutic than harmful.

  10. Surfing for mouth guards: assessing quality of online information.

    Science.gov (United States)

    Magunacelaya, Macarena B; Glendor, Ulf

    2011-10-01

    The Internet is an easily accessible and commonly used source of health-related information, but evaluations of the quality of this information within the dental trauma field are still lacking. The aims of this study are (i) to present the most current scientific knowledge regarding mouth guards used in sport activities, (ii) to suggest a scoring system to evaluate the quality of information pertaining to mouth guard protection related to World Wide Web sites and (iii) to employ this scoring system when seeking reliable mouth guard-related websites. First, an Internet search using the keywords 'athletic injuries/prevention and control' and 'mouth protector' or 'mouth guards' in English was performed on PubMed, Cochrane, SvedMed+ and Web of Science to identify scientific knowledge about mouth guards. Second, an Internet search using the keywords 'consumer health information Internet', 'Internet information public health' and 'web usage-seeking behaviour' was performed on PubMed and Web of Science to obtain scientific articles seeking to evaluate the quality of health information on the Web. Based on the articles found in the second search, two scoring systems were selected. Then, an Internet search using the keywords 'mouth protector', 'mouth guards' and 'gum shields' in English was performed on the search engines Google, MSN and Yahoo. The websites selected were evaluated for reliability and accuracy. Of the 223 websites retrieved, 39 were designated valid and evaluated. Nine sites scored 22 or higher. The mean total score of the 39 websites was 14.2. Fourteen websites scored higher than the mean total score, and 25 websites scored less. The highest total score, presented by a Public Institution Web site (Health Canada), was 31 from a maximum possible score of 34, and the lowest score was 0. This study shows that there is a high amount of information about mouth guards on the Internet but that the quality of this information varies. It should be the responsibility of health care professionals to suggest and provide reliable Internet URL addresses to patients. In addition, an appropriate search terminology and search strategy should be made available to persons who want to search beyond the recommended sites. © 2011 John Wiley & Sons A/S.

  11. Respiratory Problems Associated with Surfing in Coastal Waters

    OpenAIRE

    O Halloran, C; Silver, MW; Lahiff, M; Colford, J

    2017-01-01

    © 2016, International Association for Ecology and Health. A pilot project was conducted to examine the health status and possible adverse health effects associated with seawater exposure (microbial water-quality indicators and phytoplankton abundance and their toxins) of surfers in Monterey Bay, Central California coastal waters. Forty-eight surfers enrolled in the study and completed an initial health background survey and weekly health surveys online using Survey Monkey. Descriptive statist...

  12. MedlinePlus Guide to Healthy Web Surfing

    Science.gov (United States)

    ... not be kept up-to-date. Beware of bias--What is the purpose? Who is providing the funding? Who pays for the site? Check to see if the site is supported by public funds, donations or by commercial advertising. Advertisements should be labeled. They should say "Advertisement" ...

  13. Breaker turbulence and sediment suspension in the surf zone

    DEFF Research Database (Denmark)

    Aagaard, Troels; Hughes, Michael G

    2010-01-01

    Field measurements of fluid velocities and suspended sediment concentrations were used to investigate the relative role of coherent vortices (related to wave breaking) in suspended sediment dynamics. The measurements were obtained from a barred (intermediate-type) beach and the instrument rig...... and incoherent higher-frequency turbulence using a threshold magnitude for the vertical velocity component. Plunging breakers displayed the largest root-mean-square (RMS) and maximum vertical velocities; the latter reaching approximately 1 m s(-1). These measurements were made at an elevation of 0.15 m above...

  14. Surfing the Tsunami: Faculty Engagement with the Open Learning Initiative

    Science.gov (United States)

    Thille, Candace M.

    2013-01-01

    There are two major discussions emerging out of higher education. The first is the dual challenge of increasing completion rates and reducing the cost of instruction. The second is about the impact of technology on higher education, a topic brought to the fore in the past year by the Massive Open Online Course (MOOC) phenomenon. The Open Learning…

  15. 'Surfing the Silk Road': a study of users' experiences.

    Science.gov (United States)

    Van Hout, Marie Claire; Bingham, Tim

    2013-11-01

    The online drug marketplace called 'Silk Road' has operated anonymously on the 'Deep Web' since 2011. It is accessible through computer encrypting software (Tor) and is supported by online transactions using peer to peer anonymous and untraceable crypto-currency (Bit Coins). The study aimed to describe user motives and realities of accessing, navigating and purchasing on the 'Silk Road' marketplace. Systematic online observations, monitoring of discussion threads on the site during four months of fieldwork and analysis of anonymous online interviews (n=20) with a convenience sample of adult 'Silk Road' users was conducted. The majority of participants were male, in professional employment or in tertiary education. Drug trajectories ranged from 18 months to 25 years, with favourite drugs including MDMA, 2C-B, mephedrone, nitrous oxide, ketamine, cannabis and cocaine. Few reported prior experience of online drug sourcing. Reasons for utilizing 'Silk Road' included curiosity, concerns for street drug quality and personal safety, variety of products, anonymous transactioning, and ease of product delivery. Vendor selection appeared to be based on trust, speed of transaction, stealth modes and quality of product. Forums on the site provided user advice, trip reports, product and transaction reviews. Some users reported solitary drug use for psychonautic and introspective purposes. A minority reported customs seizures, and in general a displacement away from traditional drug sourcing (street and closed markets) was described. Several reported intentions to commence vending on the site. The study provides an insight into 'Silk Road' purchasing motives and processes, the interplay between traditional and 'Silk Road' drug markets, the 'Silk Road' online community and its communication networks. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Oscillatory infragravity wave contribution to surf zone sediment transport

    DEFF Research Database (Denmark)

    Aagaard, Troels; Greenwood, Brian

    2008-01-01

    . It is shown that infragravity sediment transports are onshore directed at the landward side of relative (incident) wave height maxima, and offshore directed at the seaward side of such maxima. If a longshore infragravity wave structure exists, such as in the case of standing edge waves, the advection process...

  17. Joint Distributed Surf Zone Environmental Model: FY96 Modeling Procedure

    National Research Council Canada - National Science Library

    Allard, Richard

    1997-01-01

    ... to the modeling and simulation community. To test this proof of concept, a suite of models were identified and tested for Camp Pendelton, CA, during two 7 day periods in January and August 1995, in which data from the Coupled Ocean...

  18. Surfing Peer-to-Peer IPTV: Distributed Channel Switching

    Science.gov (United States)

    Kermarrec, A.-M.; Le Merrer, E.; Liu, Y.; Simon, G.

    It is now common for IPTV systems attracting millions of users to be based on a peer-to-peer (P2P) architecture. In such systems, each channel is typically associated with one P2P overlay network connecting the users. This significantly enhances the user experience by relieving the source from dealing with all connections. Yet, the joining process resulting in a peer to be integrated in channel overlay usually requires a significant amount of time. As a consequence, switching from one channel to another is far to be as fast as in IPTV solutions provided by telco operators. In this paper, we tackle the issue of efficient channel switching in P2P IPTV system. This is to the best of our knowledge the first study on this topic. First, we conducted and analyzed a set of measurements of one of the most popular P2P systems (PPlive). These measurements reveal that the set of contacts that a joining peer receives from the central server are of the utmost importance in the start-up process. On those neigbors, depends the speed to acquire the first video frames to play. We then formulate the switching problem, and propose a simple distributed algorithm, as an illustration of the concept, which aims at leveraging the presence of peers in the network to fasten the switch process. The principle is that each peer maintains as neighbors peers involved in other channels, providing peers with good contacts upon channel switching. Finally, simulations show that our approach leads to substantial improvements on the channel switching time. As our algorithmic solution does not have any prerequisite on the overlays, it appears to be an appealing add-on for existing P2P IPTV systems.

  19. Sensors and Algorithms for an Unmanned Surf-Zone Robot

    Science.gov (United States)

    2015-12-01

    AXV TESIS - COMPLEMENTARY FILTER TEST % File writen by Oscar Garcia 24/08/15 clear all clc clf imu = fopen(’imucomp2.txt’,’r’); 178...IMU data fusion and filtering using a first order Kalman filter. % AXV TESIS - IMU KALMAN FILTER TEST % File writen by Oscar Garcia 30/08/15...AXV_IMU_EKF.m It performs IMU data fusion and filtering using an extended Kalman filter. % AXV TESIS - IMU EKF TEST % File writen by Oscar Garcia 30/08

  20. Spitzer ultra faint survey program (surfs up). I. An overview

    Energy Technology Data Exchange (ETDEWEB)

    Bradač, Maruša; Huang, Kuang-Han; Cain, Benjamin; Hall, Nicholas; Lubin, Lori [Department of Physics, University of California, Davis, CA 95616 (United States); Ryan, Russell; Casertano, Stefano [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Lemaux, Brian C. [Aix Marseille Université, CNRS, LAM (Laboratoire d' Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Schrabback, Tim; Hildebrandt, Hendrik [Argelander-Institut für Astronomie, Auf Dem Hügel 71, D-53121 Bonn (Germany); Gonzalez, Anthony H. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Allen, Steve; Von der Linden, Anja [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305-4060 (United States); Gladders, Mike [The University of Chicago, The Kavli Institute for Cosmological Physics, 933 East 56th Street, Chicago, IL 60637 (United States); Hinz, Joannah; Zaritsky, Dennis [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Treu, Tommaso, E-mail: marusa@physics.ucdavis.edu [Department of Physics, University of California, Santa Barbara, CA 93106 (United States)

    2014-04-20

    Spitzer UltRa Faint SUrvey Program is a joint Spitzer and Hubble Space Telescope Exploration Science program using 10 galaxy clusters as cosmic telescopes to study z ≳ 7 galaxies at intrinsically lower luminosities, enabled by gravitational lensing, than blank field surveys of the same exposure time. Our main goal is to measure stellar masses and ages of these galaxies, which are the most likely sources of the ionizing photons that drive reionization. Accurate knowledge of the star formation density and star formation history at this epoch is necessary to determine whether these galaxies indeed reionized the universe. Determination of the stellar masses and ages requires measuring rest-frame optical light, which only Spitzer can probe for sources at z ≳ 7, for a large enough sample of typical galaxies. Our program consists of 550 hr of Spitzer/IRAC imaging covering 10 galaxy clusters with very well-known mass distributions, making them extremely precise cosmic telescopes. We combine our data with archival observations to obtain mosaics with ∼30 hr exposure time in both 3.6 μm and 4.5 μm in the central 4' × 4' field and ∼15 hr in the flanking fields. This results in 3σ sensitivity limits of ∼26.6 and ∼26.2 AB magnitudes for the central field in the IRAC 3.6 and 4.5 μm bands, respectively. To illustrate the survey strategy and characteristics we introduce the sample, present the details of the data reduction and demonstrate that these data are sufficient for in-depth studies of z ≳ 7 sources (using a z = 9.5 galaxy behind MACS J1149.5+2223 as an example). For the first cluster of the survey (the Bullet Cluster) we have released all high-level data mosaics and IRAC empirical point-spread function models. In the future we plan to release these data products for the entire survey.