Littérature scientifique sur le sujet « Dead air »

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Articles de revues sur le sujet "Dead air"

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Verbeck, J. Q. J. C., G. I. M. Worm, H. Futselaar et J. C. van Dijk. « Combined air-water flush in dead-end ultrafiltration ». Water Supply 1, no 5-6 (1 juin 2001) : 393–402. http://dx.doi.org/10.2166/ws.2001.0139.

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Dead-end ultrafiltration has proven itself as a technique for reclamation of backwash water of sand filters and as a pre-treatment step for spiral wound reverse osmosis. A direct result of dead-end filtration is a decreased flux caused by the accumulation of material in the membrane pores and on the membrane surface. Different cleaning techniques are used to remove this accumulated material. Recently a new technique has been introduced, the AirFlush. This technique makes use of air to create higher turbulence as compared to a water flush. At Delft University of Technology research has started into the fundamentals of the combined air- and water-flush. First a series of experiments has been carried out to determine the different flow patterns, followed by experiments to determine which air- and water-velocities give the best cleaning. Finally head loss experiments have been done to get information about the energy dissipated in the system. The results of the head loss experiments have been compared to the theoretical head loss calculated with the theory of heterogeneous two-phase flow.
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HOGUE, CHERYL. « AIR POLLUTION CLEAR SKIES PLAN ALL BUT DEAD ». Chemical & ; Engineering News 83, no 11 (14 mars 2005) : 10. http://dx.doi.org/10.1021/cen-v083n011.p010.

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Sheikh-Omar, A., et B. Oh. « Prolapsed proventriculus in dead chicks after air shipment ». Veterinary Record 117, no 6 (10 août 1985) : 134–35. http://dx.doi.org/10.1136/vr.117.6.134.

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Zhang, Qing Feng. « Optimal Control of Air Traffic Networks ». Advanced Materials Research 945-949 (juin 2014) : 3300–3303. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.3300.

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This article will focus on the study of the dynamic dead reckoning algorithm .Dead reckoning technology is the basis for high- traffic and high -density complex airspace management , air traffic is an important component of automated decision-making system . In airspace management , all of the traffic management strategies can be generated by the aircraft 's forecast track . Depending on the precise spatial location and route on expected over time , dead reckoning implementation will significantly reduce the uncertainty in the future of aircraft flight paths , which makes the airspace and airport resources are efficiently used , the safety of an aircraft in the airspace the problem is further protection.
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Govorukhin, Yuri, Victor Krivolapov, Dmitry Paleev et Vyacheslav Portola. « Numerical Studies of the Aerodynamic Features of Dead-end Entries with Side Junction ». E3S Web of Conferences 174 (2020) : 01057. http://dx.doi.org/10.1051/e3sconf/202017401057.

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Investigations of aerodynamic processes occurring in dead-end short entriesaired by turbulent diffusion have been performed. The numerical simulation of the processes of air movement through the entry, flow stalling at the junction with the dead-end entry (for side junction), and the formation of vortices at the dead end have been carried out. The study has been done for a wide range of air flows submitted for computation of air consumption and for various geometric parameters of the dead-end entry. The sizes of the vortex structures and the flow rates in the dead endshave been determined. Based on the results of processing the simulation data, we obtained graphs of the dependences between the length of the ventilated zone of the dead end and its height and width.
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KEMPEN, PAUL MARTIN. « Minimizing Dead Space, Air Embolism, and Needle-Stick Risk ». Anesthesiology 70, no 6 (1 juin 1989) : 1034. http://dx.doi.org/10.1097/00000542-198906000-00040.

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Renata, Duffková. « Difference in Canopy and Air Temperature as an Indicator of Grassland Water Stress ». Soil and Water Research 1, No. 4 (7 janvier 2013) : 127–38. http://dx.doi.org/10.17221/6514-swr.

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In 2003–2005 in conditions of the moderately warm region of the Třeboň Basin (Czech Republic) the difference between canopy temperature (Tc) and air temperature at 2 m (Ta) was tested as an indicator of grass­land water stress. To evaluate water stress ten-minute averages of temperature difference Tc–Ta were chosen recorded on days without rainfall with intensive solar radiation from 11.00 to 14.00 CET. Water stress in the zone of the major portion of root biomass (0–0.2 m) in the peak growing season (minimum presence of dead plant residues) documented by a sudden increase in temperature difference, its value 5–12°C and unfavourable canopy temperatures due to overheating (> 30°C) was indicated after high values of suction pressure approach­ing the wilting point (1300 kPa) were reached. High variability of temperature difference in the conditions of sufficient supply of water to plants was explained by the amount of dead plant residues in canopy, value of va­pour pressure deficit (VPD), actual evapotranspiration rate (ETA) and soil moisture content. At the beginning of the growing season (presence of dead plant residues and voids) we proved moderately strong negative linear correlations of Tc–Ta with VPD and Tc–Ta with ETA rate and moderately strong positive linear correlations of ETA rate with VPD. In the period of intensive growth (the coverage of dead plant residues and voids lower than 10%) moderately strong linear correlations of Tc–Ta with VPD and multiple linear correlations of Tc–Ta with VPD and soil moisture content at a depth of 0.10–0.40 m were demonstrated.
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Su, Joseph Z., et George P. Crampton. « An Experimental Examination of Dead Air Space for Smoke Alarms ». Fire Technology 45, no 1 (7 février 2008) : 97–115. http://dx.doi.org/10.1007/s10694-008-0043-y.

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Möller, Winfried, Sheng Feng, Ulrike Domanski, Karl-Josef Franke, Gülnaz Celik, Peter Bartenstein, Sven Becker et al. « Nasal high flow reduces dead space ». Journal of Applied Physiology 122, no 1 (1 janvier 2017) : 191–97. http://dx.doi.org/10.1152/japplphysiol.00584.2016.

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Recent studies show that nasal high flow (NHF) therapy can support ventilation in patients with acute or chronic respiratory disorders. Clearance of dead space has been suggested as being the key mechanism of respiratory support with NHF therapy. The hypothesis of this study was that NHF in a dose-dependent manner can clear dead space of the upper airways from expired air and decrease rebreathing. The randomized crossover study involved 10 volunteers using scintigraphy with 81mKrypton (81mKr) gas during a breath-holding maneuver with closed mouth and in 3 nasally breathing tracheotomized patients by volumetric capnography and oximetry through sampling CO2 and O2 in the trachea and measuring the inspired volume with inductance plethysmography following NHF rates of 15, 30, and 45 l/min. The scintigraphy revealed a decrease in 81mKr gas clearance half-time with an increase of NHF in the nasal cavities [Pearson’s correlation coefficient cc = −0.55, P < 0.01], the pharynx (cc = −0.41, P < 0.01), and the trachea (cc = −0.51, P < 0.01). Clearance rates in nasal cavities derived from time constants and MRI-measured volumes were 40.6 ± 12.3 (SD), 52.5 ± 17.7, and 72.9 ± 21.3 ml/s during NHF (15, 30, and 45 l/min, respectively). Measurement of inspired gases in the trachea showed an NHF-dependent decrease of inspired CO2 that correlated with an increase of inspired O2 (cc = −0.77, P < 0.05). NHF clears the upper airways of expired air, which reduces dead space by a decrease of rebreathing making ventilation more efficient. The dead space clearance is flow and time dependent, and it may extend below the soft palate. NEW & NOTEWORTHY Clearance of expired air in upper airways by nasal high flow (NHF) can be extended below the soft palate and de facto causes a reduction of dead space. Using scintigraphy, the authors found a relationship between NHF, time, and clearance. Direct measurement of CO2 and O2 in the trachea confirmed a reduction of rebreathing, providing the actual data on inspired gases, and this can be used for the assessment of other forms of respiratory support.
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Wang, Shu Fang, Zhi Yong Yang et Ming Hai Li. « Research on Dead-End Tunneling Ventilation Control System ». Advanced Materials Research 516-517 (mai 2012) : 1188–91. http://dx.doi.org/10.4028/www.scientific.net/amr.516-517.1188.

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On the basis of analysis of ventilation requirement and CO concentration distribution character in dead-end tunneling, this paper designed the ventilation equipment layout. Furthermore, a control strategy which includes normal ventilation mode and gun smoke discharging mode is established. In view of expert experience and numerical simulation results dead-end tunneling, fuzzy control is adopted to deal with this problem. Control rules principle is described in detail. Applying direct torque speed adjustment mode, an experimental system is designed and implemented. Partial experimental results show that gun smoke emission process is fast in order to increase efficiency, while normal ventilation mode is adjustable air flow for energy conservation.
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Thèses sur le sujet "Dead air"

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Cross, Samuel. « The Air Around a Dead Man ». NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-03202007-192557/.

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Kettley, Cronfalk Elizabeth Florence. « The Sound of Corpus. : Reverberating Materiality ». Thesis, Konstfack, Ädellab/Metallformgivning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6255.

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The skin on her arms was like leather, wrinkly, so thin you could see the blood flow underneath thesurface. Ruption´s that reminded me of small universes or spider-like flowers leapt up and downher arms. She liked listening to the radio, or so I think. She was lying on the bed in the middle ofthe little house surrounded by trees. The massive furn wood dining table was tilted up against thewall, a defeeted gigant.Empty, empty, empty. Silent, silent, silent. The room was a shell, singing of what wasbefore time; a vase stood in the heart of the house, alabaster, smooth, cold holding thestill, distilled essence of emptiness, silence.-Virginia WoolfThe history of materiality can be expected because we have seen it. We can understand how it candisappear or slowly decay because we have at one point in time understood its presence. In mywork I have investigated how material and sound can help to define each other. My thoughts arethat the vase in this aspect is corpus, a recorder of its environment. The vase i.e. corpus stands forintimacy, connecting people in a home where everyday life occurs through communication. The oldvase has a presence, that presence vibrates of life that you can hint but not fully understand.Sound talks about the proportions between things in a different way by travelling between statesand time. How can we understand and access history that is invisible to the eye? GuglielmoMarconi (a pioneer in long-distance radio transmitting) believed that acoustic phenomena continuedto hang in the air. He thought of sounds as bodies of vibration whos decay extended to infinity.Marconi used a concept he called dead air, to describe silence. All sound that ever existed isaccessible to us if we know how to tune into it. What would the silence of the alabaster vase soundlike? In my examination work I have focused on sound to try and understand how it is connected tothe traces of life that are not written in history books.
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Alshatti, Rashid Ali. « Analyses of Variable Refrigerant Flow and Exergy in Air Conditioning Systems ». Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/2983.

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This thesis consists of two research problems in the air conditioning (A/C) area. For the first problem, the aim is to model and simulate a variable refrigerant flow (VRF) air conditioning system. The coefficient of performance (COP) for refrigeration or heat pump system is one of the critical parameters for designing an air conditioning system. The modeling of the system components for a VRF cycle under different cooling conditions using R-134a and R-22 as refrigerants was carried out. Calculations were performed by varying different parameters such as condenser and evaporator temperatures, and refrigerant type. The R-134a refrigerant shows a better performance when multiple evaporators are present. Part load performance evaluation was also done for both refrigerants. The simulation results compared reasonably well with available experimental data. In the second problem, the objective is to develop a mathematical model that covers the mass, energy, entropy, and exergy balances of a typical air conditioning system. The model examines how the exergy efficiency of an air conditioning system can be used to measure its performance, bypass configuration, and additional significant environmental factors that affect an A/C system's design. The effects of outside air parameters, room parameters, room sensible and latent heat loads, and dead state properties on exergy efficiency were investigated. The range of parameters covered included outside air temperature (To= 25-60oC) and relative humidity (RHo = 50-85%), sensible heat load (Qsen = 11.50-13.25 kW), latent heat load (Qlat = 3.00-4.75 kW), room air temperature (Tr= 18-25oC), and relative humidity (RHr= 30-44%), and outside-mixture air flow rate ratio (qo/qm = 0.21-0.71). Two novel dead state conditions were selected to further analyze their effects on the system. Present exergy results indicate that an A/C system is quite sensitive to air properties, sensible and latent cooling loads, and dead state conditions.
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Knight, Julian Francis. « Folio of original compositions : Three to one ; Earth to Air : Nico's piece ; Four Frames ; The Poles converge ; Scenes of Sainte Victoire ; Muted landscape ; Isle of the Dead ; Uncertain calm ; 5 miniatures for piano ». Thesis, Royal Holloway, University of London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368928.

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Suárez, Ojeda María Eugenia. « Catalytic Wet Air Oxidation Coupled with an Aerobic Treatment to Deal with Industrial Wastewater ». Doctoral thesis, Universitat Rovira i Virgili, 2006. http://hdl.handle.net/10803/8541.

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Wastewater reduction and treatment is one of the challenges faced by our consume society. As an example, in the EU, 5400 tons/year wastewater containing aromatic compounds is released having both toxic and bactericide effect. Several technologies have shown their potential for treating this kind of industrial wastewater. Nearly all of them are based on the oxidation of the organic pollutants, which are converted into carbon dioxide and water or into harmless intermediate products, more suitable for a biological treatment. Therefore, Catalytic and non-catalytic Wet Air Oxidation (CWAO and WAO) have become attractive techniques to efficiently treat organic wastewater that is either too concentrated or toxic to be biologically restored. As complete mineralisation of pollutants is extremely costly, the coupling of an initial oxidative step with a biological treatment can solve these pollution problems in a rational and less expensive way.
Hence, the main goal of this study was to demonstrate the technical feasibility of coupling an initial CWAO step with a municipal Waste Water Treatment Plant (WWTP) to deal with phenolic industrial wastewater. Therefore, it was necessary to find suitable pressure and temperature conditions in the oxidation step, so that the effluent can be treated in a municipal WWTP afterwards. The main challenge in the coupling is to achieve the right balance between the oxidation deepness (economic cost) and the effluent biodegradability (distribution of oxidation products) after the oxidation step, which ensures the success of a subsequent biological treatment.
To this end, several WAO and CWAO tests were completed (140ºC-160ºC in CWAO, 215-265ºC in WAO and 2-9 bar of oxygen partial pressure) for several model compounds typically appearing in industrial wastewater such as phenol, o-cresol, 2-chlorophenol and sodium dodecylbenzene sulfonate at concentrations higher than 8000 mg l-1of Chemical Oxygen Demand (COD). All the CWAO experiments were done in a fixed bed reactor, operating in trickle flow regime, and using activated carbon (AC) as catalyst. The WAO experiments were done in batch reactor without catalyst. The results show that model compound disappearance, COD removal and total organic carbon (TOC) abatement were very sensible to temperature change but almost independent of oxygen partial pressure. For instance, in CWAO of o-cresol at 2 bar of oxygen partial pressure, as temperature increases from 140 to 160ºC, o-cresol conversion increases from 30% to 85%, COD removal from 15 to 50% and TOC abatement from 18% and 47%. Similar behaviour was found for the other model compounds tested.
To measure biological parameters, respirometric tests were completed before and after WAO and CWAO tests and independently, for each one of the identified oxidation intermediates. In the case of WAO and CWAO effluents, these tests have enabled the determination of the biodegradability enhancement. For the oxidation intermediates, these respirometric tests have allowed obtaining the biomass yield coefficient for biodegradable carboxylic acids and to detect some co-metabolic effects, which serve to explain the biodegradability results obtained for WAO and CWAO effluents. Taking into account these results, it was possible to establish whether or not the WAO or CWAO effluents were suitable for a following treatment with non previously adapted sludge. Later, it was possible to perform a suitable procedure to couple the CWAO step with a biological lab-scale plant. The integrated treatment of wastewater with o-cresol as model pollutant achieved more than 99% of COD removal and more than 92% of CWAO intermediates removal without undesirable effects over the biomass of the biological step.
Keywords: activated carbon, activated sludge, catalytic wet air oxidation, phenolic industrial wastewater, respirometry.
La reducción del agua residual y su tratamiento es uno de los retos a los que se enfrenta nuestra sociedad de consumo. Por ejemplo, en la UE se vierten 5400 toneladas al año de efluentes industriales de compuestos aromáticos, los cuales presentan efectos tóxicos y bactericidas. Hoy en día, existen varias tecnologías que han demostrado su potencial para tratar este tipo de efluentes industriales. La mayoría de ellas están basadas en la oxidación del contaminante orgánico, el cual es transformado en dióxido de carbono y agua o en intermedios de reacción menos nocivos, más adecuados para un tratamiento biológico. Así pues, la oxidación húmeda catalítica con aire (del inglés, CWAO) usando carbón activo como catalizador y la oxidación húmeda con aire (del inglés WAO) sin catalizador se han convertido en técnicas muy atractivas para el pretratamiento efectivo de este tipo de agua residual industrial que o bien está muy concentrada o bien es muy tóxica como para ser tratada directamente en una Estación Depuradora de Aguas Residuales (EDAR) convencional. Ya que la mineralización completa del contaminante es sumamente costosa, el acoplamiento de una etapa inicial de oxidación química con un posterior tratamiento biológico puede resolver este problema de contaminación en una forma más barata y racional.
Siguiendo esta premisa, el objetivo global de este trabajo fue demostrar la viabilidad técnica del acoplamiento de una etapa inicial de CWAO con una EDAR municipal para tratar aguas residuales industriales fenólicas. Para esto fue necesario hallar las condiciones apropiadas en la etapa de oxidación, en términos de: a)
destrucción del contaminante modelo, b) preservación del catalizador en el caso de la oxidación húmeda catalítica con aire, c) distribución de intermedios y d) aumento de la biodegradabilidad. Dichos parámetros permitieron evaluar la adecuación del pretratamiento por oxidación de los efluentes industriales fenólicos para su posterior depuración en una EDAR convencional como parte de la entrada a la misma.
Para cumplir este objetivo, se realizaron varias pruebas de WAO y CWAO (140ºC-160ºC en CWAO, 215- 265ºC en WAO y de 2-9 bar presión parcial de oxígeno-PO2-) para varios contaminantes modelo típicamente presentes en aguas residuales industriales, tales como fenol, o-cresol, 2-clorofenol y dodecilbenceno sulfato de sodio (DBS) a concentraciones por encima de 8000 mg l-1 en demanda química de oxígeno (DQO). Los ensayos de CWAO fueron realizados en continuo en un reactor de lecho fijo de goteo por un tiempo total de 72 h. Se utilizó un carbón activo comercial como catalizador. El caudal de aire fue ajustado para garantizar oxígeno en exceso, mientras que el caudal de líquido fue fijado de acuerdo al peso del lecho catalítico para proporcionar un tiempo espacial del líquido de 0.12 h. Los experimentos de WAO fueron realizados en un sistema discontinuo y con tiempos de reacción de 30, 60, 90 y 120 minutos. Las temperaturas utilizadas en los experimentos WAO fueron 215, 240 y 265ºC manteniendo la presión parcial de oxígeno (PO2) en 2 bar y 9 bar. En el caso del DBS, los experimentos de WAO fuero realizados con temperaturas de 180, 200 y 220ºC y 15 bar de PO2.
Los resultados obtenidos demostraron que la destrucción del contaminante modelo y la reducción tanto de DQO como de carbono orgánico total (COT) son dependientes de los cambios de temperatura pero prácticamente independientes de los cambios en la PO2. Así pues, en la CWAO de o-cresol a 2 bar de PO2, un cambio en la temperatura de 140ºC a 160ºC implica un aumento en la destrucción de o-cresol de 30 a 85%, en la eliminación de DQO de 15 a 50% y en la eliminación de COT de 18 al 47%. Un comportamiento similar fue hallado para el resto de contaminantes modelo.
La biodegradabilidad de los efluentes procedentes de los distintos ensayos de oxidación y de los intermedios de oxidación fue determinada mediante pruebas respirométricas. Para los efluentes de WAO y CWAO estas pruebas permitieron obtener el grado de aumento de la biodegradabilidad producido por cada una de las condiciones de oxidación empleadas. Para el caso de los intermedios de reacción, estas pruebas respirométricas permitieron determinar el coeficiente de rendimiento biomasa/sustrato para los ácidos carboxílicos biodegradables y detectar algunos comportamientos co-metabólicos; los cuales a su vez, sirvieron para explicar los resultados obtenidos en cuanto a la biodegradabilidad de los efluentes procedentes de WAO y CWAO.
Teniendo en cuenta estos resultados, fue posible establecer si los efluentes de WAO o CWAO eran adecuados para su posterior tratamiento con un lodo activo no aclimatado. De esta manera se estableció un protocolo de acoplamiento apropiado de la etapa de CWAO con una planta biológica a escala laboratorio. El tratamiento integrado de las aguas residuales de o-cresol alcanzó una eliminación de DQO de más del 99% y una destrucción de los intermedios de CWAO de más del 92%, sin causar efectos adversos sobre la biomasa de la etapa biológica.
Palabras clave: aguas residuales industriales fenólicas, carbón activo, lodos activos, oxidación húmeda catalítica con aire, respirometría.
La reducció de l'aigua residual i el seu tractament és un dels reptes als quals s'enfronta la nostra societat de consum. Com a exemple, a la UE s'aboquen 5400 tones a l'any d'efluents industrials que contenen compostos aromàtics, els quals presenten efectes tòxics i bactericides. Avui, existeixen diverses tecnologies que han demostrat el seu potencial per a tractar aquest tipus d'efluents industrials. La majoria d'elles estan basades en l'oxidació dels contaminants orgànics, el qual és transformat en diòxid de carboni i aigua o en intermedis de reacció menys nocius, més adequats per a un tractament biològic. Així doncs, l'oxidació humida catalítica amb aire amb carbó actiu com catalitzador (de l'anglès, CWAO) i l'oxidació humida amb aire (de l'anglès, WAO) sense catalitzador s'han convertit en tècniques molt atractives pel pretractament efectiu d'aquest tipus d'aigua residual industrial que o bé està molt concentrada o bé és molt tòxica com per a ser tractada directament a una Estació Depuradora d'Aigües Residuals (EDAR) convencional. Com que la mineralització complerta del contaminant és summament costosa, l'acoblament d'una etapa inicial d'oxidació amb un tractament biològic pot resoldre aquest problema de contaminació d'una forma més barata i racional.
Seguint aquesta premissa, l'objectiu global d'aquest treball va ser demostrar la viabilitat tècnica de l'acoblament d'una etapa inicial de CWAO amb una EDAR municipal per a tractar aigües residuals industrials fenóliques. Per això, va ser necessari trobar les condicions apropiades a l'etapa d'oxidació, en termes de: a) destrucció del contaminant model, b) preservació del catalitzador en el cas de l'oxidació humida catalítica amb aire, c)
distribució d'intermedis i d) augment de la biodegradabilidad. Aquests paràmetres van permetre avaluar l'adequació del pretractament per oxidació dels efluents industrials fenólics per a la seva posterior depuració a una EDAR convencional, com partde l'entrada a la mateixa.
Per a assolir aquest objectiu, es van realitzar diverses proves de WAO i CWAO (140ºC-160ºC en CWAO, 215-265ºC en WAO i de 2-9 bar de pressió parcial d'oxigen-PO2-) per a diversos contaminants model típicament presents a les aigües residuals industrials, com poden ser el fenol, o-cresol, 2-clorofenol i dodecilbenzè sulfat de sodi (DBS) a concentracions per sobre de 8000 mg l-1 de Demanda Química d'Oxigen (DQO). Els experiments de CWAO van ser realitzats en continu en un reactor de llit fix de goteig per un temps total de 72 h. Es va utilitzar un carbó actiu comercial com catalitzador. El cabal d'aire va ser ajustat per a garantir oxigen en excés i el cabal de líquid va ser fixat en funció del pes del llit catalític per a proporcionar un temps espacial del líquid de 0.12 h. Els experiments de WAO van ser realitzats a un sistema discontinu i amb un temps de reacció de 30, 60, 90 i 120 minuts. Les temperatures utilitzades als experiments WAO van ser 215, 240 i 265ºC, mantenint la PO2 a 2 bar i 9 bar. Pel cas del DBS, els experiments de WAO van ser realitzats a temperatures de 180, 200 i 220ºC i 15 bar de PO2.
Els resultats obtinguts van demostrar que la destrucció del contaminant model i la reducció tant de l'DQO com de Carboni Orgànic Total (COT) són dependents dels canvis de temperatura però pràcticament independents dels canvis a la PO2. A mode d'exemple, per a la CWAO d'o-cresol a 2 bar de PO2, un canvi a la temperatura de 140ºC a 160ºC implica un augment de la destrucció d'o-cresol de 30 a 85%, de l'eliminació de DQO de 15 a 50% i de l'eliminació de COT de 18 al 47%. Un comportament similar va ser trobat per a la resta de contaminants model.
La biodegradabilidad dels efluents procedents dels diferents assaigs d'oxidació i dels intermedis d'oxidació va ser determinada mitjançant proves respirométriques. Pels efluents de WAO i CWAO aquestes proves van permetre obtenir el grau d'augment de la biodegradabilidad produït per cadascuna de les condicions d'oxidació emprades. Pel cas dels intermedis de reacció, aquestes proves respirométriques van permetre determinar el coeficient de rendiment biomassa/substrat per als àcids carboxílics biodegradables i detectar alguns comportaments co-metabòlics; els quals, van servir per a explicar els resultats obtinguts pel que fa a la biodegradabilidad dels efluents procedents de WAO i CWAO. Tenint en compte aquests resultats, va ser possible establir si els efluents de WAO o CWAO eren adequats per al seu posterior tractament amb un llot actiu no aclimatat. D'aquesta manera es va establir un protocol d'acoblament apropiat de l'etapa de CWAO amb una planta biològica a escala de laboratori. El tractament integrat de les aigües residuals d'o-cresol va assolir una eliminació de DQO de més del 99% i una destrucció dels intermedis de CWAO de més del 92%, sense causar efectes nocius sobre la biomassa de l'etapa biològica.
Paraules clau: aigües residuals industrials fenólicas, carbó actiu, llots actius, oxidació humida catalítica amb aire, respirometria.
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Frantzen, Joey L. Ehresman Kenneth L. « Electronic maneuvering board and dead reckoning tracer decision aid for the officer of the deck / ». Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA397270.

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Thesis (M.S. in Computer Science--Naval Postgraduate School, Sept. 2001.
Thesis advisor(s): Riehle, Richard D. ; Luqi. "September 2001." Includes bibliographical references (p. 195). Also Available online.
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Frantzen, Joey L., et Kenneth L. Ehresman. « Electronic maneuvering board and dead reckoning tracer decision aid for the officer of the deck ». Thesis, Monterey, California. Naval Postgraduate School, 2001. http://hdl.handle.net/10945/1650.

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The U.S. Navy currently bases the majority of our contact management decisions around a time and manning intensive paper-based Maneuvering Board process. Additional manning requirements are involved on many Naval Ships in order to accurately convey the information to the OOD and/or the Commanding Officer. When given situations where there exist multiple contacts, the current system is quickly overwhelmed and may not provide Decision-Makers a complete and accurate picture in a timely manner. The purpose of this research is to implement a stand-alone system that will provide timely and accurate contact information for Decision-Makers. By creating a reliable, automated system in a format that is familiar to all Surface Warfare Officers we will provide the Navy with a valuable decision-making tool, while increasing ease of data exchange and reducing current redundancies and manning inefficient practices. Our software design is based upon the Unified Modeling Language (UML). UML allows us to construct a software model that is supported by the Ada programming language. Our design is based upon these fundamental tenants: Non- Operating System dependent, Non-Hardware System dependent, Extensible and Modular design. Ada provides a certified compiler, making our code robust and assuring the βbuyerγ that the program does what we advertise it to do.
US Navy (USN) authors
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Goeke, Robert P., et Christopher M. VanZoest. « The art of the deal : how can the Air Force successfully execute renewable energy transactions ? » Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/10489.

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MBA Professional Report
The purpose of this paper is to explore the methods the Air Force uses to procure renewable energy. To comply with Executive Order 13423, agencies must ensure that at least half of all renewable energy required under Energy Policy Act of 2005 comes from new renewable sources (developed after January 1, 1999) (Department of Energy, n.d.b). The Air Force is currently on track to meet the requirements of this legislation and is also the Department of Defense (DoD) leader in total renewable energy procured. The contracting tools used to procure renewable energy are Power Purchase Agreements and Enhanced Use Leases. The processes involved with Power Purchase Agreements and Enhanced Use Leases are unique and challenging. Additionally, renewable energy procurement includes many other participants or interested parties, which is contrary to the standard contracting process. Working within this renewableenergy arena requires the use of public-private partnerships in order for these deals to be successful. This paper will describe and evaluate the entire process used to procure renewable energy including parties involved, tools to execute, examples of successful projects, and it will explain how the Air Force can better support the procurement of renewable energy.
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Mutemwa, Muyowa. « A Mobile Deaf-to-hearing communication aid for medical diagnosis ». University of the Western Cape, 2011. http://hdl.handle.net/11394/2964.

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>Magister Scientiae - MSc
Many South African Deaf people use their mobile phones for communication with SMSs yet they would prefer to converse in South African Sign Language. Deaf people with a capital `D' are different from deaf or hard of hearing as they primarily use sign language to communicate. This study explores how to design and evaluate a prototype that will allow a Deaf person using SASL to tell a hearing doctor how s/he is feeling and provide a way for the doctor to respond. A computer{based prototype was designed and evaluated with the Deaf people in a previous study. Results from the user trial of the computer{based mock{up indicated that Deaf users would like to see the prototype on a cell phone. Those user trial results, combined with our own user survey results conducted with Deaf people, are used as requirements. We built a prototype for a mobile phone browser by embedding SASL videos inside XHTML pages using Adobe Flash. The prototype asks medical questions using SASL videos. These questions are arranged in an organized way that helps in identifying a medical problem. The answers to the questions are then displayed in English and shown to the doctor on the phone. A content authoring tool was also designed and implemented. The content authoring tool is used for populating the prototype in a context free manner allowing for plug and play scenarios such as a doctor's office, Department of Home A airs or police station. A focus group consisting of Deaf people was conducted to help in the design and pilot trial of the system. A final user trial was conducted with more than thirty Deaf people and the results are presented and analyzed. Data is collected with questionnaires, semi-structured interviews and video recordings. The results indicate that most of the Deaf people found the system easy to learn, easy to navigate through, did not get lost and understood the sign language in the videos on the mobile phone. The hand gestures and facial expressions on the sign language videos were clear. Most of them indicated they would like to use the system for free, and that the system did not ask too many questions. Most of them were happy with the quality of the sign language videos on the mobile phone and would consider using the system in real life. Finally they felt their private information was safe while using the system. Many South African Deaf people use their mobile phones for communication with SMSs yet they would prefer to converse in South African Sign Language. Deaf people with a capital `D' are different from deaf or hard of hearing as they primarily use sign language to communicate. This study explores how to design and evaluate a prototype that will allow a Deaf person using SASL to tell a hearing doctor how s/he is feeling and provide a way for the doctor to respond. A computer{based prototype was designed and evaluated with the Deaf people in a previous study. Results from the user trial of the computer{based mock{up indicated that Deaf users would like to see the prototype on a cell phone. Those user trial results, combined with our own user survey results conducted with Deaf people, are used as requirements. We built a prototype for a mobile phone browser by embedding SASL videos inside XHTML pages using Adobe Flash. The prototype asks medical questions using SASL videos. These questions are arranged in an organized way that helps in identifying a medical problem. The answers to the questions are then displayed in English and shown to the doctor on the phone. A content authoring tool was also designed and implemented. The content authoring tool is used for populating the prototype in a context free manner allowing for plug and play scenarios such as a doctor's office, Department of Home A airs or police station. A focus group consisting of Deaf people was conducted to help in the design and pilot trial of the system. A final user trial was conducted with more than thirty Deaf people and the results are presented and analyzed. Data is collected with questionnaires, semi-structured interviews and video recordings. The results indicate that most of the Deaf people found the system easy to learn, easy to navigate through, did not get lost and understood the sign language in the videos on the mobile phone. The hand gestures and facial expressions on the sign language videos were clear. Most of them indicated they would like to use the system for free, and that the system did not ask too many questions. Most of them were happy with the quality of the sign language videos on the mobile phone and would consider using the system in real life. Finally they felt their private information was safe while using the system.
South Africa
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Soltani-Farani, A. A. « Sound visualisation as an aid for the deaf : a new approach ». Thesis, University of Surrey, 1998. http://epubs.surrey.ac.uk/844112/.

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Visual translation of speech as an aid for the deaf has long been a subject of electronic research and development. This thesis is concerned with a technique of sound visualisation based upon the theory of the primacy of dynamic, rather than static, information in the perception of speech sounds. The goal is design and evaluation of a system to display the perceptually important features of an input sound in a dynamic format as similar as possible to the auditory representation of that sound. The human auditory system, as the most effective system of sound representation, is first studied. Then, based on the latest theories of hearing and techniques of auditory modelling, a simplified model of the human ear is developed. In this model, the outer and middle ears together are simulated by a high-pass filter, and the inner ear is modelled by a bank of band-pass filters the outputs of which, after rectification and compression, are applied to a visualiser block. To design an appropriate visualiser block, theories of sound and speech perception are reviewed. Then the perceptually important properties of sound, and their relations to the physical attributes of the sound pressure wave, are considered to map the outputs from the auditory model onto an informative and recognisable running image-like the one known as cochleagram. This conveyor-like image is then sampled by a window of 20 milliseconds duration at a rate of 50 samples per second, so that a sequence of phase-locked, rectangular images is produced. Animation of these images results in a novel method of spectrography displaying both the time-varying and the time-independent information of the underlying sound with a high resolution in real time. The resulting system translates a spoken word into a visual gesture, and displays a still picture when the input is a steady state sound. Finally the implementation of this visualiser system is evaluated through several experiments undertaken by normal-hearing subjects. In these experiments, recognition of the gestures of a number of spoken words, is examined through a set of two-word and multi-word forced-choice tests. The results of these preliminary experiments show a high recognition score (40-90 percent, where zero represents chance expectation) after only 10 learning trials. General conclusions from the results suggest: a potential quick learning of the gestures, language independence of the system, fidelity of the system in translating the auditory information, and persistence of the learned gestures in the long-term memory. The results are very promising and motivate further investigations.
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Livres sur le sujet "Dead air"

1

Jaco, Charles. Dead air. New York : Ballantine Books, 1999.

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Lupica, Mike. Dead air. New York : Villard Books, 1986.

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Larson, Bob. Dead air. Nashville : Thomas Nelson Publishers, 1991.

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Dead air. Sudbury, Ont : Scrivener Press, 2012.

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Banks, Iain M. Dead air. London : Abacus, 2003.

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Copyright Paperback Collection (Library of Congress), dir. Dead air. New York : Berkley Prime Crime, 1998.

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Dead air. Brandon, MS : Dogwood Press, 2004.

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Goldberg, Ed. Dead air. New York : Berkley Prime Crime, 1998.

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Caroll, Robin. Dead air. New York : Steeple Hill, 2010.

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Jaco, Charles. Dead air. New York : Ballantine Books, 1998.

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Chapitres de livres sur le sujet "Dead air"

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Mukherjee, Upamanyu Pablo. « Dead Air : Indra Sinha ». Dans Postcolonial Environments, 134–62. London : Palgrave Macmillan UK, 2010. http://dx.doi.org/10.1057/9780230251328_7.

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Kishcha, Pavel, Boris Starobinets et Pinhas Alpert. « Modeling of Foehn-Induced Extreme Local Dust Pollution in the Dead Sea Valley ». Dans Air Pollution Modeling and its Application XXV, 433–37. Cham : Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-57645-9_68.

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White, R. S. « A Plague on Both Your Houses : War from the Air, the Civilian Dead and Modern Poetry ». Dans Pacifism and English Literature, 232–53. London : Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583641_10.

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Suzuki, Hitoshi. « The Deal : Financial Aid and Local Content ». Dans Japanese Investment and British Trade Unionism, 99–124. Singapore : Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-9058-0_5.

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Fink, Jonathan, et Patricia Gober. « Using Stakeholder Engagement and Visualization to Aid Decision-Making About Water Use in The Middle East ». Dans The Jordan River and Dead Sea Basin, 257–74. Dordrecht : Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-2989-8_14.

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Nolte, Peter, Renate Printzen et Günter Esser. « Sprach — Farbbild — Transformation (SFT) — the Conversion of Sound to Coloured Light as a Visual Aid in Speech Therapy ». Dans Interactive Learning Technology for the Deaf, 175–86. Berlin, Heidelberg : Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-58024-6_14.

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Hasan Baseri, Nur Hasnifa, Ee Yeng Ng, Alireza Safdari, Mahmoud Moghavvemi et Noraisyah Mohamed Shah. « A Low Cost Street Crossing Electronic Aid for the Deaf and Blind ». Dans IFMBE Proceedings, 73–78. Singapore : Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-7554-4_12.

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Goienetxea, Izaro, Iñigo Mendialdua et Basilio Sierra. « On the Use of Matrix Based Representation to Deal with Automatic Composer Recognition ». Dans AI 2018 : Advances in Artificial Intelligence, 531–36. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-03991-2_48.

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Ghule, Supriya, et Mrunalini Chavaan. « RETRACTED CHAPTER : Implementation of Hand Gesture Recognition System to Aid Deaf-Dumb People ». Dans Lecture Notes in Electrical Engineering, 183–94. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-8391-9_14.

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Ghule, Supriya, et Mrunalini Chavaan. « Retraction Note to : Implementation of Hand Gesture Recognition System to Aid Deaf-Dumb People ». Dans Lecture Notes in Electrical Engineering, C1. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-8391-9_49.

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Actes de conférences sur le sujet "Dead air"

1

Fu, Jingshun, et Nobuo Kurihara. « Intake Air Control of SI Engine Using Dead-Time Compensation ». Dans SAE Powertrain & Fluid Systems Conference & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States : SAE International, 2003. http://dx.doi.org/10.4271/2003-01-3267.

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Vanjpe, Omkar K., Mundla Narasimhappa et Arun D. Mahindrakar. « Global attitude estimation and dead reckoning of a mobile spherical robot using extended Kalman filter ». Dans AIR 2019 : Advances in Robotics 2019. New York, NY, USA : ACM, 2019. http://dx.doi.org/10.1145/3352593.3352623.

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Fakhraee, Ahmad, Manoucher Rad, Hamid Amini et Mehdi Rishehri. « Ship Hull Drag Reduction Using Bottom Air Injection ». Dans ASME 2007 26th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2007. http://dx.doi.org/10.1115/omae2007-29020.

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Air cavity ship concept has received some interest due to its potential on viscous resistance reduction for high speed craft. Air-cavity ships (ACS) are advanced marine vehicles that use air injection at the wetted hull surfaces to improve a vessel’s hydrodynamic characteristics. Air is supplied through nozzles under a profiled bottom to generate an air cavity beneath such a ship, so that a steady air layer separates a part of the bottom from contact with water, consequently reducing hydrodynamic resistance. Resistance tests were conducted with two forms: first of which was planning catamaran hull form, and second one was an alternative form with an air cavity injection under its bottom which was tested both without any air injection and with three different air injection ranges. Dead rise angle was fixed to 23 degree during both model tests. Frictional resistance was calculated from wetted surface area and compared with total resistance. It is clear from these results that improvements in high speed planning catamarans can be realized by using bottom air injection. Drag reduction achieved on these model is within 13–23 percent.
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Wu, Yan Ling, Hee Joo Poh, Kah Wai Lum et Xiu Qing Xing. « Numerical Study of Dead-End Micro Polymer Electrolyte Membrane Fuel Cell ». Dans ASME 2008 Fluids Engineering Division Summer Meeting collocated with the Heat Transfer, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/fedsm2008-55308.

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In this paper, 3D full size simulation on single cell dead-end micro PEMFC is carried out using Computational Fuel Cell Dynamics (CFDC) analysis. The active area in this Micro PEMFC is about 10 cm2, producing 1A of current under standard condition (25 °C and 1 atm). The dead end anode configuration is achieved by increasing the air flow rate well above stoichometric at the cathode to obtain the complete depletion of hydrogen at anode exit. It is also assumed that the presence of water is only in the vapor phase. Different types (single serpentine and triple serpentine) of gas channel design in dead-end anode are studied and results are compared. The polarization curves for both designs as well as contour plots for the different cell region are presented.
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Hawkins, Lawrence, Alexei Filatov, Shamim Imani et Darren Prosser. « Test Results and Analytical Predictions for Rotor Drop Testing of an AMB Expander/Generator ». Dans ASME Turbo Expo 2006 : Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90283.

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A cryogenic gas expander system that incorporates a high performance, high-speed permanent magnet, direct-drive generator and low loss magnetic bearings is described. Flow loop testing to 30,000 rpm was completed at the system manufacturer’s facility in January 2005, and field installation is scheduled for October 2005. As part of the system testing, the rotor was dropped onto the backup bearings multiple times at an intermediate speed and at 30,000 rpm. Orbit and time-history data from a full speed drop and spin down are presented and discussed in detail. A transient, nonlinear rotordynamic analysis simulation model was developed for the machine to provide insight into the dynamic behavior. The model includes the dead band clearance, the flexible backup bearing support and hard stop. Model predictions are discussed relative to the test data.
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Schjo̸lberg, Ingrid, Morten Hyllseth, Gunleiv Skofteland et Ha˚vard Nordhus. « Dynamic Analysis of Compressor Trips in the Sno̸hvit LNG Refrigerant Circuits ». Dans ASME Turbo Expo 2008 : Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-51235.

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Compressors are key components in the refrigerant circuits of the Sno̸hvit LNG plant and contain large amounts of mechanical energy. Thus it is imperative that the control system is able to keep the compressor out of surge in case of driver trip. A dynamic process simulator describing the total LNG plant has been developed by Kongsberg Process Simulation and the simulator has been applied in the engineering phase for the design and process verification. The simulator has also been used to verify the robustness of the closed loop refrigerant circuits and to verify that the refrigerant compressors are sufficiently protected after a driver trip. The presented work demonstrates the value of dynamic simulations for verification of compressor protection systems. In addition it shows the importance of using correct data for polar inertia of the rotating equipment, as well as the opening and dead times of the anti-surge valves. It is recommended to include a sensitivity analysis of these parameters as part of plant verification studies.
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Iacovides, Hector, Diamantis Kounadis, Brian E. Launder, Jiankang Li et Zeyuan Xu. « Experimental Study of the Flow and Thermal Development of a Row of Cooling Jets Impinging on a Rotating Concave Surface ». Dans ASME Turbo Expo 2004 : Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53244.

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The paper reports an experimental study of impingement cooling in a rotating passage of semi-cylindrical cross-section. Cooling fluid is injected from a row of five jet holes along the centerline of the flat surface of the passage and strikes the concave surface. The cooling passage rotates orthogonally about an axis parallel to that of the jets. Tests have been carried out, using water, both within the passage and as the jet fluid, at a fixed Reynolds number of 15,000, for clockwise and anti-clockwise rotation. Local Nusselt number measurements, using the liquid-crystal technique, show that under stationary conditions a high Nusselt number region develops around each impingement point, with secondary peaks half-way between impingement points. Rotation reduces heat transfer, leads to the disappearance of all secondary peaks and also, surprisingly, of some of the primary peaks. Flow visualization tests suggest that these changes in thermal behavior are caused because rotation increase the spreading rate of the jets. LDA and PIV measurements are also presented. They show that under stationary conditions the five jets exhibit a similar behavior, with their cores remaining intact up to the point of impingement at the top dead center. The LDA and PIV studies help explain the rather surprising thermal behavior under rotating conditions.
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Choi, Benjamin, et Andrew Provenza. « Passive Fault Tolerance for a Magnetic Bearing Under PID Control ». Dans ASME Turbo Expo 2001 : Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/2001-gt-0456.

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NASA Glenn Research Center (GRC) has developed a Fault-Tolerant Magnetic Bearing Suspension rig to enhance the safety of the bearing system for multiple component failures. A simple proportional-integral-derivative (PID) controller with no fault detection mechanisms was tested in a passive way where the initial bias current and control gains for all the eight heteropolar poles were not changed for the remaining active poles in the fault situations. The action of the integral term in the controller generated autonomous corrective actions for the pole failures to return the rotor to the set point (middle position) after the failure transient. The system stability and control of the rotor position were maintained over the entire speed range, where the rotor passes through the rigid body critical speeds and other rotor disturbances, provided that there was sufficient position stiffness and damping at low speeds. As far as the summation of force vectors of two attracting forces and rotor weight is zero, the passive fault tolerance was successfully demonstrated by using as few as two active poles out of the eight independent poles from each radial bearing (that is simply, 12 out of 16 poles dead). The rotor was spun without losing stability or desired position up to the rig’s maximum allowable speed of 20,000 rpm.
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Berruti, Teresa, Christian M. Firrone et Muzio M. Gola. « A Test Rig for Non-Contact Travelling Wave Excitation of a Bladed Disk With Underplatform Dampers ». Dans ASME Turbo Expo 2010 : Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22879.

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The paper presents a static test rig called “Octopus” designed for the validation of numerical models aimed at calculating the nonlinear dynamic response of a bladed disk with underplatform dampers (UPDs). The test rig supports a bladed disk on a fixture and each UPD is pressed against the blade platforms by wires pulled by dead weights. Both excitation system and response measurement system are noncontacting. The paper features the design and the set-up of the noncontacting excitation generated by electromagnets placed under each blade. A travelling wave excitation is generated according to a desired engine order by shifting the phase of the harmonic force of one electromagnet with respect to the contiguous exciters. Since the friction phenomenon generated by UPDs introduces nonlinearities on the forced response, the amplitude of the exciting force must be kept constant at a known value on every blade during step-sine test to calculate Frequency Response Functions. The issue of the force control is therefore addressed since the performance of the electromagnet changes with frequency. The system calibration procedure and the estimated errors on the generated force are also presented. Examples of experimental tests that can be performed on a dummy integral bladed disk (blisk) mounted on the rig are described in the end.
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Cairo, Ronald R., et Kathleen A. Sargent. « A Scientific Approach to the Process Development of Bonded Attachments for High Speed Rotor Application ». Dans ASME Turbo Expo 2000 : Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0355.

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The quest for increased work per stage of compression to reduce overall gas turbine engine system cost has placed extreme demands on the high-pressure turbine (HPT) system. As an example, the HPT is required to operate at unprecedented levels of AN2 (the product of turbine annulus area and mechanical speed squared) to enable compressor performance goals to be met. The typical approach of mechanically attaching blades via firtree or dovetail configured mechanical attachments, limits rotor speed because of the life limiting broach slots (stress concentrators) in the disk rim. Exacerbating this problem is the fact that the disk lugs, which react the blade loading, impose a dead load. Higher disk speed results in higher blade loading requiring a deeper or wider lug to support the blade. This in turn results in a wider disk bore to support the deeper, dead load lug region. The dilemma is that higher speed results in larger stress concentrations at the rim and a wider disk bore to support the added parasitic rim load. The answer to this dilemma lies in creating an Integrally Bladed Rotor (IBR) in which the blades are integral with the disk. Since typically, for an HPT, the blades are single crystal and the disk equiaxed nickel alloys, the IBR design suggested precludes absolute machining as the fabrication approach. A solution lies in metallurgically bonding the blades to the disk rim. Bonded airfoil attachments have the potential to increase AN2 and component life by 9–10% by eliminating broach induced stress concentrations as noted. Moreover, bonded attachments can reduce external rim loading by upward of 15% with a corresponding reduction in disk weight. The key to the solution is a controlled, economical process to concurrently join a full complement of HPT blades in a repeatable manner. This paper discusses how a scientific approach and creative design practice can lead to such a process. Three alternative tooling concepts, and one universal tool that allows independent use of two of these concepts, were developed. Tool stresses and deflections, tool load paths, and bond pressure profiles were all quantified through ANSYS Finite Element Analyses and closed form analytical solutions. Prior experience has shown that joint strength is sensitive to the bond pressure level. Therefore, the tool materials and geometry were iterated upon until the pressure applied to the blade bond plane was as uniform as possible. Since absolute uniformity is elusive when deformable bodies are part of the bond load train, accurately determining the maximum and minimum bond plane pressure is absolutely essential for subsequent joint characterization and design allowable determination. This allows localized working stresses in the designed attachment to be compared to specific, bond pressure driven, allowable strengths rather than an average strength. This paper will show how applying a scientific approach to the development of a critical technology process can reduce both the cost and risk of process development.
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Rapports d'organisations sur le sujet "Dead air"

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Dahl, Arden B. The Warthog. The Best Deal the Air Force Never Wanted. Fort Belvoir, VA : Defense Technical Information Center, janvier 2003. http://dx.doi.org/10.21236/ada442118.

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Bowden, Jimmy L. Oversight of the Air Force - What is the Audit Component and How Can Air Force Managers Deal with It Effectively ? Fort Belvoir, VA : Defense Technical Information Center, mai 1988. http://dx.doi.org/10.21236/ada202039.

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NAVAL POSTGRADUATE SCHOOL MONTEREY CA. The Art of the Deal : How Can the Air Force Successfully Execute Renewable Energy Transactions. Fort Belvoir, VA : Defense Technical Information Center, décembre 2010. http://dx.doi.org/10.21236/ada536325.

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James, Christian, Ronald Dixon, Luke Talbot, Stephen James, Nicola Williams et Bukola Onarinde. Assessing the impact of heat treatment on antimicrobial resistant (AMR) genes and their potential uptake by other ‘live’ bacteria. Food Standards Agency, août 2021. http://dx.doi.org/10.46756/sci.fsa.oxk434.

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Addressing the public health threat posed by AMR is a national strategic priority for the UK, which has led to both a 20-year vision of AMR and a 5-year (2019 to 2024) AMR National Action Plan (NAP). The latter sets out actions to slow the development and spread of AMR with a focus on antimicrobials. The NAP used an integrated ‘One-Health’ approach which spanned people, animals, agriculture and the environment, and calls for activities to “identify and assess the sources, pathways, and exposure risks” of AMR. The FSA continues to contribute to delivery of the NAP in a number of ways, including through furthering our understanding of the role of the food chain and AMR.Thorough cooking of food kills vegetative bacterial cells including pathogens and is therefore a crucial step in reducing the risk of most forms of food poisoning. Currently, there is uncertainty around whether cooking food is sufficient to denature AMR genes and mobile genetic elements from these ‘dead’ bacteria to prevent uptake by ‘live’ bacteria in the human gut and other food environments - therefore potentially contributing to the overall transmission of AMR to humans. This work was carried out to assess these evidence gaps.
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Martín, A., L. Cirrottola, A. Froehly, R. Rossi et C. Soriano. D2.2 First release of the octree mesh-generation capabilities and of the parallel mesh adaptation kernel. Scipedia, 2021. http://dx.doi.org/10.23967/exaqute.2021.2.010.

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This document presents a description of the octree mesh-generation capabilities and of the parallel mesh adaptation kernel. As it is discussed in Section 1.3.2 of part B of the project proposal there are two parallel research lines aimed at developing scalable adaptive mesh refinement (AMR) algorithms and implementations. The first one is based on using octree-based mesh generation and adaptation for the whole simulation in combination with unfitted finite element methods (FEMs) and the use of algebraic constraints to deal with non-conformity of spaces. On the other hand the second strategy is based on the use of an initial octree mesh that, after make it conforming through the addition of templatebased tetrahedral refinements, is adapted anisotropically during the calculation. Regarding the first strategy the following items are included:
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McKenna, Patrick, et Mark Evans. Emergency Relief and complex service delivery : Towards better outcomes. Queensland University of Technology, juin 2021. http://dx.doi.org/10.5204/rep.eprints.211133.

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Emergency Relief (ER) is a Department of Social Services (DSS) funded program, delivered by 197 community organisations (ER Providers) across Australia, to assist people facing a financial crisis with financial/material aid and referrals to other support programs. ER has been playing this important role in Australian communities since 1979. Without ER, more people living in Australia who experience a financial crisis might face further harm such as crippling debt or homelessness. The Emergency Relief National Coordination Group (NCG) was established in April 2020 at the start of the COVID-19 pandemic to advise the Minister for Families and Social Services on the implementation of ER. To inform its advice to the Minister, the NCG partnered with the Institute for Governance at the University of Canberra to conduct research to understand the issues and challenges faced by ER Providers and Service Users in local contexts across Australia. The research involved a desktop review of the existing literature on ER service provision, a large survey which all Commonwealth ER Providers were invited to participate in (and 122 responses were received), interviews with a purposive sample of 18 ER Providers, and the development of a program logic and theory of change for the Commonwealth ER program to assess progress. The surveys and interviews focussed on ER Provider perceptions of the strengths, weaknesses, future challenges, and areas of improvement for current ER provision. The trend of increasing case complexity, the effectiveness of ER service delivery models in achieving outcomes for Service Users, and the significance of volunteering in the sector were investigated. Separately, an evaluation of the performance of the NCG was conducted and a summary of the evaluation is provided as an appendix to this report. Several themes emerged from the review of the existing literature such as service delivery shortcomings in dealing with case complexity, the effectiveness of case management, and repeat requests for service. Interviews with ER workers and Service Users found that an uplift in workforce capability was required to deal with increasing case complexity, leading to recommendations for more training and service standards. Several service evaluations found that ER delivered with case management led to high Service User satisfaction, played an integral role in transforming the lives of people with complex needs, and lowered repeat requests for service. A large longitudinal quantitative study revealed that more time spent with participants substantially decreased the number of repeat requests for service; and, given that repeat requests for service can be an indicator of entrenched poverty, not accessing further services is likely to suggest improvement. The interviews identified the main strengths of ER to be the rapid response and flexible use of funds to stabilise crisis situations and connect people to other supports through strong local networks. Service Users trusted the system because of these strengths, and ER was often an access point to holistic support. There were three main weaknesses identified. First, funding contracts were too short and did not cover the full costs of the program—in particular, case management for complex cases. Second, many Service Users were dependent on ER which was inconsistent with the definition and intent of the program. Third, there was inconsistency in the level of service received by Service Users in different geographic locations. These weaknesses can be improved upon with a joined-up approach featuring co-design and collaborative governance, leading to the successful commissioning of social services. The survey confirmed that volunteers were significant for ER, making up 92% of all workers and 51% of all hours worked in respondent ER programs. Of the 122 respondents, volunteers amounted to 554 full-time equivalents, a contribution valued at $39.4 million. In total there were 8,316 volunteers working in the 122 respondent ER programs. The sector can support and upskill these volunteers (and employees in addition) by developing scalable training solutions such as online training modules, updating ER service standards, and engaging in collaborative learning arrangements where large and small ER Providers share resources. More engagement with peak bodies such as Volunteering Australia might also assist the sector to improve the focus on volunteer engagement. Integrated services achieve better outcomes for complex ER cases—97% of survey respondents either agreed or strongly agreed this was the case. The research identified the dimensions of service integration most relevant to ER Providers to be case management, referrals, the breadth of services offered internally, co-location with interrelated service providers, an established network of support, workforce capability, and Service User engagement. Providers can individually focus on increasing the level of service integration for their ER program to improve their ability to deal with complex cases, which are clearly on the rise. At the system level, a more joined-up approach can also improve service integration across Australia. The key dimensions of this finding are discussed next in more detail. Case management is key for achieving Service User outcomes for complex cases—89% of survey respondents either agreed or strongly agreed this was the case. Interviewees most frequently said they would provide more case management if they could change their service model. Case management allows for more time spent with the Service User, follow up with referral partners, and a higher level of expertise in service delivery to support complex cases. Of course, it is a costly model and not currently funded for all Service Users through ER. Where case management is not available as part of ER, it might be available through a related service that is part of a network of support. Where possible, ER Providers should facilitate access to case management for Service Users who would benefit. At a system level, ER models with a greater component of case management could be implemented as test cases. Referral systems are also key for achieving Service User outcomes, which is reflected in the ER Program Logic presented on page 31. The survey and interview data show that referrals within an integrated service (internal) or in a service hub (co-located) are most effective. Where this is not possible, warm referrals within a trusted network of support are more effective than cold referrals leading to higher take-up and beneficial Service User outcomes. However, cold referrals are most common, pointing to a weakness in ER referral systems. This is because ER Providers do not operate or co-locate with interrelated services in many cases, nor do they have the case management capacity to provide warm referrals in many other cases. For mental illness support, which interviewees identified as one of the most difficult issues to deal with, ER Providers offer an integrated service only 23% of the time, warm referrals 34% of the time, and cold referrals 43% of the time. A focus on referral systems at the individual ER Provider level, and system level through a joined-up approach, might lead to better outcomes for Service Users. The program logic and theory of change for ER have been documented with input from the research findings and included in Section 4.3 on page 31. These show that ER helps people facing a financial crisis to meet their immediate needs, avoid further harm, and access a path to recovery. The research demonstrates that ER is fundamental to supporting vulnerable people in Australia and should therefore continue to be funded by government.
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