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Zeitschriftenartikel zum Thema "Mer – Surfaces"

1

Yoshihiko, Amino. „Les Japonais et la mer“. Annales. Histoire, Sciences Sociales 50, Nr. 2 (April 1995): 235–58. http://dx.doi.org/10.3406/ahess.1995.279364.

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L'archipel japonais compte plus de 3700 îles, grandes et petites, et possède un littoral de près de 28 000 kilomètres. Son relief est extrêmement tourmenté : les zones montagneuses, souvent volcaniques, occupent 60 % du territoire, les collines couvrent 11 % du pays et les piémonts 4 %. Plateaux et basses terres ne représentent guère plus de 25 % de la superficie du pays. Les rivières sont nombreuses et dévalent souvent les montagnes à une allure torrentielle. Les vallées sont encaissées et le terrain particulièrement accidenté. Les montagnes, les rivières et la mer occupent une part importante du paysage et, pour ceux qui vivent sur cet archipel, les surfaces cultivables n'ont jamais été très vastes.
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Consiglio, Giuseppe, und Giuseppe Forte. „Molecular dynamics study of coil-to-globule transition in a thermo-responsive oligomer bound to various surfaces: hydrophilic surfaces stabilize the coil form“. Physical Chemistry Chemical Physics 20, Nr. 47 (2018): 29754–63. http://dx.doi.org/10.1039/c8cp05396k.

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The structural and dynamical properties of 40-mer of thermo-responsive polymer PNIPAM covalently bound to different surfaces have been studied, at different temperatures, by means of molecular dynamics simulations.
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Britten, Michel, Margaret L. Green, Marcel Boulet und Paul Paquin. „Deposit formation on heated surfaces: effect of interface energetics“. Journal of Dairy Research 55, Nr. 4 (November 1988): 551–62. http://dx.doi.org/10.1017/s0022029900033331.

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SummaryDeposit formation was measured in a model laboratory plant in which whole milk was in contact with a heated surface at 100 °C for 1 h. The effect of the interfacial properties of various poly mer-coated surfaces on the amount and the adhesion strength of deposit was determined. The nature of the surface influenced the formation of deposit only slightly, but had a large effect on its adhesion strength. From correlation analysis, the polar contribution to surface energy was identified as the main factor influencing the deposit adhesion strength. These results suggest that the type of interactions at the surface govern the ease of removal of deposit.
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Guney, Dilvin, Aysin Tulunay, Funda Pepedil, Isik Kaygusuz, Cafer Adiguzel, Tülin Tuglular, Muzaffer Demir, Emel Eksioglu-Demiralp und Fikriye Uras. „Tyro3, Axl Ve Mer (TAM) Receptors On Surfaces of Mononuclear Cells in Patients with B-Cell Chronic Lymphocytic Leukemia“. Blood 120, Nr. 21 (16.11.2012): 4588. http://dx.doi.org/10.1182/blood.v120.21.4588.4588.

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Abstract Abstract 4588 Background: Tyro 3 (Sky), Axl, and Mer receptors are members of the family of tyrosine kinases and Gas6 is their ligand molecule. In some types of cancer, upregulation of Axl/Gas6 indicated a worse prognosis, but an opposite situation was observed in renal “cell” carcinoma. This contradiction may suggest that Axl/Gas6 pathway varies depending on the type of cancer. The objective of this study is to investigate TAM receptors on surfaces of mononuclear cells in patients with B-Cell chronic lymphocytic leukemia (B-Cell-CLL). Material & Methods: B-Cell-CLL patients (grade 0–1, according to the classification of RAI), who were not on a drug treatment, were recruited in this study (n= 20; 9 female, 11 male). Their ages were 44 to 74 (mean: 63), and the control group consisted of 13 healthy volunteers (5 female, 8 male), whose age range is 20–89 (mean: 36). Mononuclear cells were isolated by density gradient centrifugation, and then surface TAM receptors were detected by flow cytometry. Mononuclear cell were stained with the primary antibodies against Tyro3, Axl and Mer. Results: The percentage of the surface TAM receptors on mononuclear cells from the patient group (25–75% interquartile range): Tyro 3= 25.50 (4.2– 45.62); Axl= 17/55 (5.57– 36.32), and Mer= 19.90 (1.92– 37.55). In the control group the following values were obtained: Tyro 3= 2.60 (1.35–3.25); Axl= 0.9 (0.4–2.6), and Mer= 2.50 (0.35–3.65). The percentage of three of them was significantly higher in the B-Cell-CLL group than those in the control group (P<0.01). Conclusion: In conclusion, this preliminary study showed that TAM receptors on surfaces of mononuclear cells are higher in patients with B-Cell-CLL patients than the control group. Gas6/TAM signaling may play a potential role in the pathogenesis of B Cell-CLL. Further studies are required to elucidate the actual role of Gas6/TAM signaling in B-Cell-CLL. Gas6/TAM signaling might be a new strategic goal for the treatment of B-Cell-CLL. Disclosures: No relevant conflicts of interest to declare.
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Branchford, Brian R., Luke Law, Susan Sather, Gary Brodsky, H. Shelton Earp, Xiaodong Wang, Stephen Frye, Douglas K. Graham und Jorge A. Di Paola. „A Small Molecule Inhibitor of the Gas6/Mer Pathway Inhibits Platelet Activation and Thrombosis with Equal Efficacy to, but Greater Potency Than, iMer, the Novel MerTK Splice Variant“. Blood 120, Nr. 21 (16.11.2012): 3303. http://dx.doi.org/10.1182/blood.v120.21.3303.3303.

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Abstract Abstract 3303 Background: Growth Arrest Specific gene 6 (Gas6) signals through platelet-surface Mer receptors, leading to platelet activation and thrombus stabilization via activation of PI3K and Akt, and β3 integrin phosphorylation. This amplifies outside-in signaling via αIIb β3, a necessary step for stable platelet aggregation. iMer is a truncated form of the Mer receptor tyrosine kinase's extracellular domain, produced by alternative splicing, that inhibits Gas6 signaling. A selective UNC Mer small molecule inhibitor (UNC Mer TKI) inhibits signaling by inhibiting Mer tyrosine phosphorylation. Objectives: We hypothesized that inhibiting the Gas6/Mer pathway with UNC Mer TKI would decrease platelet activation responses and thrombus formation to a greater degree than iMer. So, we comparatively evaluated iMer's and UNC Mer TKI's inhibition of Gas6/Mer signaling in vitro and in vivo. Methods: We measured the effect on platelet inhibiton of iMer and UNC Mer TKI using lab assays of human platelet function and murine thrombosis models. In vitro studies included standard aggregometry and aggregate formation on collagen surfaces in a microfluidic flow chamber. In vivo studies included a FeCl3-induced model of carotid artery injury and a collagen/epinephrine-induced pulmonary embolism (PE) model to compare thrombosis protection between littermate C57BL/6 mice treated with inhibitors or vehicle control. A paired t-test was used to compare samples in aggregation, microfluidic flow surface area coverage, as well as elapsed time to initial and stable occlusions in the FeCl3model and survival time in the PE model. Results/Discussion: Inhibitor-treated platelets exhibited significantly decreased aggregation. Collagen-stimulated samples treated with 1.2 μM iMer had mean aggregation of 45 +/− 13% (Stand Dev), compared to 72 +/− 8% in controls (n=6, p=0.02). 1.2 μM UNC Mer TKI-treated samples had mean aggregation of 56 +/−15%, compared to 74 +/−10% in controls (n=5, p<0.01). Adhesion of platelets to collagen under physiologic flow conditions resulted in 1.9% (+/− 1%) coverage in 1.2 μM iMer-treated samples compared to 8.7 +/− 2% mean surface area coverage in controls (n=7, p<0.001). 1.2 μM UNC Mer TKI-treated samples exhibited 8.5 +/−8.8% surface area coverage, compared to 19.2 +/− 15.7% for control-treated samples (n=5 in quadruplicate, p<0.01), and 2.4 +/−1.7% for abciximab-treated positive controls. Both iMer- and UNC Mer TKI-treated samples have a higher average percentage of small platelet aggregates (1–10 platelets/aggregate) compared to controls, which had a higher average percentage of large aggregates (>10 platelets/aggregate). Following 6% FeCl3-induced carotid artery injury for analysis of iMer's thrombosis protection, vehicle-treated control mice (n=6) had a hazard ratio for stable artery occlusion of 7.9 (95%CI 1.7–36.3) compared to 30mg/kg iMer-treated mice (n=8, p<0.01). The 1.2 μM iMer treated mice also demonstrated significantly prolonged time to both initial (p=0.03) and stable occlusion (p=0.02), suggesting decreased thrombus stability. In analysis of UNC Mer TKI's thrombosis inhibition, vehicle-treated control mice (n=10) had a hazard ratio for stable artery occlusion of 4.8 (95%CI 1.4–15.8) compared 3 mg/kg UNC Mer TKI-treated mice (n=9, p=0.02). Times to initial (p=0.06) and stable (p<0.01) occlusions were also prolonged in the UNC Mer TKI-treated mice compared to controls. In the PE model, 1.2 μM iMer-treated mice (n=5) had longer mean survival (14.1 +/− 14.5 min) following collagen/epinephrine injection than controls (n=5, 1.78 +/12.4 min, p=NS), with 2 iMer–treated mice and no controls surviving for 30 min. A much greater effect was seen with the 3 mg/kg UNC Mer TKI-treated mice (n=5) who had a mean survival time of 37.24 +/−31.2 min, with 3 surviving for a full 60 min, compared to 1.63 +/− 0.6 min (p=0.03) for controls (n=5), of which only 1 survived for 60 min. Conclusions: iMer and UNC Mer TKI are Gas6/Mer inhibitors that decrease platelet activation and protect mice from thrombosis, and may have translational applications as novel anti-platelet agents. UNC Mer TKI has similar efficacy, and higher potency, especially in the animal models where similar (FeCl3 model) or superior (PE model) results were seen with a 10-fold lower concentration. UNC Mer TKI also has the advantage of possible oral preparation, which may increase its potential therapeutic appeal. Disclosures: Branchford: University of Colorado: This author has provisional patent considerations for iMer, This author has provisional patent considerations for iMer Patents & Royalties. Sather:University of Colorado: This author has provisional patent considerations for iMer, This author has provisional patent considerations for iMer Patents & Royalties. Brodsky:University of Colorado: This author has provisional patent considerations for iMer, This author has provisional patent considerations for iMer Patents & Royalties. Graham:University of Colorado: This author has provisional patent considerations for iMer, This author has provisional patent considerations for iMer Patents & Royalties.
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Zhou, Junsong, Lu Wang und Yi Wu. „Gas6 Receptors, Tyro3, Axl and Mer, Differentially Participate in Glycoprotein VI-Mediated Platelet activation“. Blood 118, Nr. 21 (18.11.2011): 364. http://dx.doi.org/10.1182/blood.v118.21.364.364.

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Abstract Abstract 364 Growth arrest-specific gene 6 (Gas6) has three receptors on platelets - Tyro3, Axl and Mer. It has been shown that these three receptors are equally important in platelet activation (J Clin Invest. 2005;115:237–46), and they synergizes with ADP receptor for platelet activation, but not with collagen receptor (J Thromb Haemost. 2010;8:1797–808). Considering the fact that Tyro3, Axl or Mer plays a distinct role in the function of endothelial cells and leukocytes, we hypothesized that these three receptors play specific role in platelet activation, and examined the role of each receptor in Gycoprotein VI (GPVI)-mediated platelet activation using single receptor knockout mice. In response to 100 ng/ml convulxin or 5 ng/ml poly(PHG), a GPVI-specific synthetic peptide, the aggregation of Axl−/− or Tyro3−/− platelets was almost completely prevented. However, the aggregation of Mer−/− platelets was only delayed, and still could reach the maximum level. In the presence of 100 ng/ml convulxin or 5 ng/ml poly(PHG), the spreading of Axl−/− or Tyro3−/− platelets, but not Mer−/− platelets, on fibrinogen-coated surfaces was markedly inhibited. Moreover, convulxin-stimulated P-selectin expression and JON/A binding were both significantly decreased in Axl−/− and Tyro3−/− platelets, but not in Mer−/− platelets. Upon stimulation with 100 ng/ml convulxin, tyrosine phosphorylation of Syk, linker for activation of T cells (LAT), SLP-76(SH2 domain-containing leukocyte protein of 76) and phospholipase C (PLCγ2) was markedly reduced in the Axl−/− or Tyro3−/− platelets, but not in the Mer−/− platelets. Interestingly, anti-Axl or anti-Tyro3 antibody (20 mg/ml) completely blocked convulxin-stimulated human platelet aggregation, however, the neutralizing anti-Gas6 antibody (60 mg/ml) did not have any effect, suggesting the homodimer formation of Axl or Tyro3 is involved in GPVI-mediated platelet activation. As detected by flow cytometry, there was no difference in the expression of GPVI and integrin aIIbb3 on membrane surface among Tyro-3−/−, Axl−/−, Mer−/− and wild type platelets. In conclusion, Gas6 receptors are not equally important in platelet activation, Axl and Tyro3 play more critical role than Mer in GPVI-mediated platelet activation. The trans-interaction of Axl or Tyro3 mediates cell-cell contact-dependent activation, which facilitates the activation of GPVI in platelets. Thus, Axl and Tyro3 may serve as better targets than Mer for the development of new antiplatelet agents. Disclosures: No relevant conflicts of interest to declare.
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Jousselme, A., D. Grenier und H. T. Huynh. „Analyse de la distorsion spectrale des images radar de surfaces de mer“. Canadian Journal of Electrical and Computer Engineering 29, Nr. 4 (Oktober 2004): 243–51. http://dx.doi.org/10.1109/cjece.2004.1426052.

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Barragan, Antonio, Victor Fernandez, Qijun Chen, Anne von Euler, Mats Wahlgren und Dorothe Spillmann. „The Duffy-binding-like domain 1 of Plasmodium falciparumerythrocyte membrane protein 1 (PfEMP1) is a heparan sulfate ligand that requires 12 mers for binding“. Blood 95, Nr. 11 (01.06.2000): 3594–99. http://dx.doi.org/10.1182/blood.v95.11.3594.

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Abstract The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), present on the surfaces of parasitized red blood cells (pRBC), mediates rosetting, a virulent phenotype. Here, we show that pRBC specifically bind heparan sulfate (HS) and heparin onto their surfaces and that the rosetting ligand PfEMP1 specifically adheres to heparin–Sepharose when extracted from the surfaces of radioiodinated infected RBC. An analysis of the binding properties of the different regions of PfEMP1 provides evidence that the Duffy-binding–like domain-1 (DBL-1) is the predominant ligand involved in HS and heparin binding. Soluble DBL-1 requires a minimal heparin fragment size of a 12-mer (≈4 kd) for binding and is critically dependent on N-sulfation. A 12-mer is also the minimal heparin fragment that disrupts naturally formed rosettes. DBL-1 binds specifically to erythrocytes and also to HS from endothelial cells and human aorta but not to chondroitin sulfate A, suggesting that different PfEMP1s mediate adhesion to distinct glycosaminoglycans in individual malaria parasites. Present data suggest that HS on endothelial cells may also be involved in the sequestration of pRBC. Elucidation of these binding mechanisms opens up new possibilities for therapeutic strategies targeting adhesive interactions of pRBC.
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Barragan, Antonio, Victor Fernandez, Qijun Chen, Anne von Euler, Mats Wahlgren und Dorothe Spillmann. „The Duffy-binding-like domain 1 of Plasmodium falciparumerythrocyte membrane protein 1 (PfEMP1) is a heparan sulfate ligand that requires 12 mers for binding“. Blood 95, Nr. 11 (01.06.2000): 3594–99. http://dx.doi.org/10.1182/blood.v95.11.3594.011k21_3594_3599.

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The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), present on the surfaces of parasitized red blood cells (pRBC), mediates rosetting, a virulent phenotype. Here, we show that pRBC specifically bind heparan sulfate (HS) and heparin onto their surfaces and that the rosetting ligand PfEMP1 specifically adheres to heparin–Sepharose when extracted from the surfaces of radioiodinated infected RBC. An analysis of the binding properties of the different regions of PfEMP1 provides evidence that the Duffy-binding–like domain-1 (DBL-1) is the predominant ligand involved in HS and heparin binding. Soluble DBL-1 requires a minimal heparin fragment size of a 12-mer (≈4 kd) for binding and is critically dependent on N-sulfation. A 12-mer is also the minimal heparin fragment that disrupts naturally formed rosettes. DBL-1 binds specifically to erythrocytes and also to HS from endothelial cells and human aorta but not to chondroitin sulfate A, suggesting that different PfEMP1s mediate adhesion to distinct glycosaminoglycans in individual malaria parasites. Present data suggest that HS on endothelial cells may also be involved in the sequestration of pRBC. Elucidation of these binding mechanisms opens up new possibilities for therapeutic strategies targeting adhesive interactions of pRBC.
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Riul, A., A. Dhanabalan, L. H. C. Mattoso, L. M. de Souza, E. A. Ticianelli und O. N. Oliveria. „Characterization of 16-mer polyaniline composite Langmuir–Blodgett films“. Thin Solid Films 327-329 (August 1998): 576–80. http://dx.doi.org/10.1016/s0040-6090(98)00716-0.

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Dissertationen zum Thema "Mer – Surfaces"

1

Veras, Guimarães Pedro. „Surfaces de mer et dissipation d'énergie“. Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0001/document.

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Les formulations et modèles de vagues stochastiques sont les outils les plus traditionnels pour l’évaluation et la prévision des états de mer. Cependant, la prise en compte de nombreux processus physiques essentiels à l’évolution des vagues reste souvent lacunaire dans ces types d’approches. Une des raisons possible est notamment que peu d’observations viennent documenter ces processus. La dissipation des ondes est ainsi mal quantifiée par les méthodes d'observation traditionnelles dans tout l’éventail des conditions océaniques. Dans ce contexte, le travail présenté dans cette thèse explore plus avant les conditions menant au déferlement à travers la modulation de l'énergie des ondes courtes par de fort courants de marée et par des ondes plus longues.Dans cette étude, nous avons profité des campagnes de mesure BBWAVES, spécialement conçues pour acquérir de la donnée dans des zones d’interactions vagues courants.Ces campagnes ont notamment permis de tester une nouvelle bouée dérivante conçue pour la mesure des vagues dans des zones à forts courants de marées. Grâce à des mesures simultanées en zones de forts courants, il a été possible de mettre en évidence des lacunes dans la modélisation des états de mer, et l’influence vraisemblable des erreurs dans la modélisation atmosphérique pour ces conditions. Cette thèse a également tiré parti d’une campagne de mesure stéréo-vidéo d’états de mer en Mer Noire afin d’étudier différents aspects du déferlement des vagues dans une grande variété de conditions d'état de mer bimodales. Ces mesures ont permis de mettre en évidence une modulation des ondes courtes par des longues et une incidence sur les propriétés de déferlement
Stochastic wave formulations and models are the most common tools for the assessment and forecast of sea surface conditions. Their ability to account for some of the processes encountered by waves during their evolution remains however a central question. Among other processes, the wave dissipation is for instance still poorly quantified and traditional methods for wave measurements fail to proper insight into its physics in a wide range of conditions. In this context, the work presented in this PhD aims to explore available observation techniques for their application to several quantitative aspects of the dissipation of wave energy, and particularly for short wave modulated by strong tidal currents, for short wave modulated by longer waves. This work takes advantage of the BBWAVES oceanic campaigns, especially planned to explore questions related to wave and current interactions. Data from a large variety of sensors are analyzed. The campaign provides the ground for the test of a new design of drifting buoy aimed at measuring waves in areas of strong tidal current. Its performances are verified and the description it provides of the area is explored. From simultaneous measurements, it was possible to highlight the actual inaccuracies in wave model capabilities as well as the contribution of the error contained in the atmospheric modeling over strong tidal currents to the misevaluation of sea states. This work also used an extensive dataset from a stereo video experiment in the Black Sea to investigate wave breaking in bimodal sea state conditions. These measurements have revealed the influence of long wave modulation over short wave breaking
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Miret, David. „Diffraction électromagnétique par des surfaces rugueuses en incidence rasante : application à la surface de la mer“. Phd thesis, Toulon, 2014. http://tel.archives-ouvertes.fr/tel-01019965.

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L'incidence rasante est un problème spécifique, qui apparaît notamment lorsqu'une antenne est placée sur un mât (télécommunications, défense...) ou sur la côte (surveillance environnementale ou militaire de l'espace maritime). Elle rend la modélisation du problème de diffraction difficile, de par le faible niveau de rétrodiffusion et l'importance de phénomènes complexes comme la diffusion multiple. La question reste importante même si l'écho est très faible, puisqu'il est potentiellement suffisant pour perturber le bon fonctionnement de systèmes antennaires microondes sur un navire. Il porte de plus des informations intéressantes sur l'état de la mer, comme cela a été démontré aux bandes HF et VHF. Un modèle rigoureux de diffraction tridimensionnelle précédemment développé est étendu au calcul des quatre polarisations fondamentales (polarisations Horizontale et Verticale des ondes incidente et réfléchie). Il permet désormais de prendre en compte la conductivité finie de la surface, point crucial dans le cas d'une polarisation incidente Verticale. L'opérateur hyper-singulier impliqué dans l'équation intégrale discrétisée par la méthode des moments est étudié pour évaluer la précision des calculs numériques.Les méthodes approchées de diffraction permettent des calculs numériques beaucoup plus rapides, et sont donc en pratique incontournables. Le modèle rigoureux est donc utilisé, en conjonction avec des données expérimentales, pour servir de référence permettant d'étudier la précision, en incidence rasante et dans le cas de la surface de la mer, de ces méthodes approchées. Nous étudions en particulier la méthode à deux échelles GOSSA, et proposons une correction à son comportement aux angles rasants.Le mouvement de la surface de la mer crée un décalage de fréquence radar dans l'onde rétrodiffusée (effet Doppler), décalage mesuré expérimentalement et que l'algorithme de méthode des moments permet de simuler. Nous étudions par des simulations bidimensionnelles l'évolution du décalage Doppler micro onde avec l'incidence, et l'influence des nonlinéarités de la surface de la mer. Le comportement limite en incidence rasante est précisé, et les contributions respectives des phénomènes électromagnétiques et hydrodynamiques discutées.
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Miret, David. „Diffraction électromagnétique par des surfaces rugueuses en incidence rasante : application à la surface de la mer“. Electronic Thesis or Diss., Toulon, 2014. http://www.theses.fr/2014TOUL0002.

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L’incidence rasante est un problème spécifique, qui apparaît notamment lorsqu'une antenne est placée sur un mât (télécommunications, défense…) ou sur la côte (surveillance environnementale ou militaire de l'espace maritime). Elle rend la modélisation du problème de diffraction difficile, de par le faible niveau de rétrodiffusion et l’importance de phénomènes complexes comme la diffusion multiple. La question reste importante même si l’écho est très faible, puisqu’il est potentiellement suffisant pour perturber le bon fonctionnement de systèmes antennaires microondes sur un navire. Il porte de plus des informations intéressantes sur l’état de la mer, comme cela a été démontré aux bandes HF et VHF. Un modèle rigoureux de diffraction tridimensionnelle précédemment développé est étendu au calcul des quatre polarisations fondamentales (polarisations Horizontale et Verticale des ondes incidente et réfléchie). Il permet désormais de prendre en compte la conductivité finie de la surface, point crucial dans le cas d'une polarisation incidente Verticale. L’opérateur hyper-singulier impliqué dans l’équation intégrale discrétisée par la méthode des moments est étudié pour évaluer la précision des calculs numériques.Les méthodes approchées de diffraction permettent des calculs numériques beaucoup plus rapides, et sont donc en pratique incontournables. Le modèle rigoureux est donc utilisé, en conjonction avec des données expérimentales, pour servir de référence permettant d’étudier la précision, en incidence rasante et dans le cas de la surface de la mer, de ces méthodes approchées. Nous étudions en particulier la méthode à deux échelles GOSSA, et proposons une correction à son comportement aux angles rasants.Le mouvement de la surface de la mer crée un décalage de fréquence radar dans l’onde rétrodiffusée (effet Doppler), décalage mesuré expérimentalement et que l’algorithme de méthode des moments permet de simuler. Nous étudions par des simulations bidimensionnelles l’évolution du décalage Doppler micro onde avec l’incidence, et l’influence des nonlinéarités de la surface de la mer. Le comportement limite en incidence rasante est précisé, et les contributions respectives des phénomènes électromagnétiques et hydrodynamiques discutées
The grazing incidence is a specific problem, which appears especially when an antenna is placed on a mast (telecommunications, defence...) or on the coast (environmental or military maritime spatial monitoring). The modelization of the scattering process in such a configuration is difficult, due to low backscattering and to the importance of complex phenomena such as multiple scattering. The issue remains important even if the echo is very low, because it is potentially sufficient to disturb the proper functioning of microwave antenna systems on a ship. Moreover, it carries interesting informations about the sea state, as was demonstrated in HF and VHF bands.A rigorous model of the three-dimensional scattering process, previously developed, is extended to the computation of the scattered fiel in the four fundamental polarizations (Horizontal and Vertical polarization of incident and reflected waves). It is now possible to take into account the finite conductivity of the surface, a crucial point when the incident field is vertically polarized. The hyper- singular operator involved in the integral equation discretized by the method of moments is studied to evaluate the accuracy of numerical calculations.The approximate methods of diffraction allow much faster numerical calculations, and are therefore essential. The rigorous model is used in conjunction with experimental data, as a reference to study the accuracy of such approximate methods, in the case of the sea surface at grazing incidence. We study in particular the two-scale method GOSSA and propose a correction to its behaviour at grazing angles. The motion of the sea surface creates a frequency shift in the radar backscattered wave (Doppler effect). This offset can be measured experimentally, our algorithm allows us to simulate it. We proceed to two-dimensional simulations showing the evolution of the Doppler shift with respect to the grazing angle, and show the influence of the nonlinearities in the sea model. The limit of the mean Doppler shift at very low grazing angles is studied, and the respective contributions of electromagnetic and hydrodynamic phenomena are discussed
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4

Lurton, Thibaut. „Modélisation et simulation de l'interaction entre onde électromagnétique et surfaces de mer“. Télécom Bretagne, 2010. http://www.theses.fr/2010TELB0118.

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L'objectif de cette thèse consiste en une modélisation numérique de l'interaction entre une onde électromagnétique émanant d'un radar d'observation aéroporté et une scène marine, c'est-à-dire une étendue d'eau de mer de caractéristiques physiques déterminées, portant éventuellement un ou plusieurs objets de composition métallique en surface, et d'évolution temporelle donnée. À cette fin, l'étude que nous avons menée fait appel à différentes techniques de modélisation numérique de la propagation ondulatoire électromagnétique : on s'est dans un premier temps penché sur l'utilisation de la technique des différences finies, puis sur le principe TLM (Transmission-Line Matrix), hérité du domaine des micro-ondes. Chacune des deux méthodes est appliquée au comportement de l'onde électromagnétique de manière locale, à proximité de la surface de mer uniquement, la simulation de la propagation en espace libre étant assurée par des moyens géométriques. Nous proposons dans un premier temps une brève étude critique de l'opportunité des méthodes numériques et de leur faisabilité en termes de demande en ressources de calcul notamment. Après cette évaluation théorique, un suivi du développement de l'implantation de la solution retenue est proposé. Nous présentons par la suite diverses applications de notre méthode de simulation : évaluation de la surface équivalente radar d'un patch de mer, dérivation de cartes de réflectivité, extension de l'évaluation de la surface équivalente radar à une grande zone de mer, mise en évidence de l'effet de la rugosité sur la puissance rétrodiffusée, simulation de l'observation par radar à synthèse d'ouverture d'un objet manufacturé sur une scène de mer, et comparaison de l'observation de scènes marines statiques et mouvantes. Le champ d'application des travaux présentés est large. Le travail de thèse s'inscrit dans le cadre du projet de développement MODENA, mené à l'échelle régionale bretonne, dont l'objectif est le développement d'outils de simulation d'acquisition radar au dessus de la surface de l'océan. À cet égard, les avancées théoriques et pratiques détaillées dans ce rapport de thèse offrent des perspectives intéressantes quant à la modélisation de telles observations
The aim of this thesis consists in numerically modelling the interaction between an electromagnetic wave emitted by an airborne observation radar and a maritime scene, i. E. An expanse of sea water of determined physical characteristics, possibly bearing one or several objects of metallic constitution on its surface, with a given temporal evolution. To this end, the study we carried out draws on different numerical modelling techniques for electromagnetic wave propagation: to begin with, the Finite-Differences Time-Domain (FDTD) technique was investigated, then the Transmission-Line Matrix method, inherited from the microwave domain, was studied. Each of the two methods is applied to the behaviour of the electromagnetic wave locally, in the vicinity of the sea surface only, the free space propagation simulation being undertaken through geometrical means. We propose a brief critical survey of the appropriateness of numerical methods and of their feasibility, particularly in terms of computation resources. After this theoretical study, we follow the development and implementation of the solution retained. We subsequently present several applications of our simulation method: radar cross section evaluation for small sea patches, derivation of reflectivity maps, extension of the radar cross section estimation to a large sea zone, yielding of the sea surface roughness influence upon the backscattered power, simulation of the synthetic aperture radar observation of a manufactured object in a sea scene, and comparison of the observation of static and moving sea scenes. The area of application of the work presented here is wide. The frame for the thesis is the MODENA development project, led at the Breton regional level, and whose objective is the development of radar acquisition simulation tools above the ocean's surface. In that respect, the theoretical and practical advances detailed in this thesis report widen the scope of the
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Bessin, Paul. „Évolution géomorphologique du Massif armoricain depuis 200 MA : approche Terre-Mer“. Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S180/document.

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Le Massif armoricain est un domaine de socle cadomo-varisque ouest-européen de faible altitude (maximum 400m), caractérisé par des surfaces d'aplanissement, dont l'évolution géologique et géomorphologique mésozoïque et cénozoïque est débattue. L'objectif de cette étude est de reconstituer la croissance du relief de ce massif. Une analyse géomorphologique, à terre et à mer, des surfaces d'aplanissement à été réalisée. Celle-ci est basée sur leur (i) cartographie, (i) chronologie relative, (iii) relations avec les profils d'altération et (iv) datation au moyen des dépôts sédimentaires datés les fossilisant. Six surfaces d'aplanissement ont été identifiées et datées et la plupart sont exhumées. Elles sont d'âge anté-Jurassique inférieur (PS1 à PS3), anté-Jurassique moyen (PS4), ante-Crétacé inférieur (PS5) et Paléocène (PS6). Au moins deux phases d'enfouissement/exhumation ont été identifiées : (1) un enfouissement au cours du Jurassique suivi d'une exhumation au Crétacé inférieur et (2) un enfouissement au Crétacé supérieur suivi d'une dénudation du Crétacé terminal à l'Éocène inférieur. La première période d'exhumation est probablement reliée à l'initiation puis l'ouverture du rift entre les paques Ibérie et Eurasie (Golfe de Gascogne) et la seconde à la convergence entre ces deux plaques. Enfin, les mouvements verticaux cénozoïque du massif ont été quantifiés à partir (i) de la position des sédiments marins datés et de milieu de sédimentation connus et (ii) des paléoniveaux marins respectifs de ces dépôts déduits de différentes chartes eustatiques. Ces travaux mettent en évidence (i) une surrection au Paléocène, (ii) une susidence à l'Éocène supérieur et (iii) la surrection déjà caractérisée au Pléistocène
The Armoricain massif is a west-european Cadomo-variscan domain of low altitude (maximum 400 m), characterized by planation surfaces, whose Mesozoic and Cenozoic geological and geomorphological evolution is still debated. The purpose of this study is to retrace the growth of this relief. A geomorphological analysis of the planation surfaces was performed on land and at sea. It is based on their (i) mapping, (ii) relative chronology, (iii) relationships with weathering mantles and (iv) dating using dated sediments that seal those them. Six stepped planation surfaces have been identified and mapped and most of them are exhumed. They are pre-early Jurassic (PS1 to PS3), pre-middle Jurassic (PS4), pre-late Cretaceous (PS5) and Paleocene (PS6). At least two phases of burial and exhumation have been identified: (1) burial in Jurassic time followed by denudation during the early Cretaceous and (2) burial in late Cretaceous time followed dy denudation during the latest Cretaceous to early Eocene. The first period of exhumation is probably related to the initiation and break-up of the rift between Iberia and Eurasia (Bay of Biscay) and the second to the convergence betwenn these two plates. At last, Cenozoic vertical movements of the massif have been quantified from (i) position of dated marine sediments of known depositional environment and (ii) their respective paleo-sea levels deduced from different eustatic charts. This work highlights (i) Paleocene uplift, (ii) late Eocene subsidence and (iii) the already characterized Pleistocene uplift
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Demarty, Yaël. „Modélisation cohérente de la diffusion électromagnétique par des surfaces de mer tridimensionnelles en incidence rasante : application aux radars HF à ondes de surface“. Paris 6, 2008. http://www.theses.fr/2008PA066293.

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Cette thèse repose sur l’analyse des interactions électromagnétiques (EM) entre les ondes de surface, aux fréquences HF, et une surface de mer évoluant dans le temps. Un simulateur comprenant trois modules spécifiques est développé. Le premier élément permet de modéliser une surface de mer en 3D variant dans le temps, par application de la théorie linéaire des vagues. Le second fait interagir une onde EM en incidence rasante avec une surface de mer grâce à un modèle exact qui s’appuie sur la méthode des moments. Enfin, un outil de post-traitement offre la possibilité de tracer et d’analyser des spectres Doppler (SD) résultants. Une étude portant sur des surfaces statiques puis dynamiques est menée. Elle fait apparaître respectivement le phénomène de résonance de Bragg et l’effet Doppler. Des données déjà publiées ou mesurées indiquent une bonne adéquation avec les SD simulés. Finalement, l’effet sur les SD, de la présence d’un film de polluant sur la surface de mer, est analysé.
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Jousselme, Anne-Laure. „Contribution aux études de signaux radar de surfaces de mer et mise au point d'un traitement rapide“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25423.pdf.

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Steinmetz, François. „Étude de la correction de la diffusion atmosphérique et du rayonnement solaire réfléchi par la surface agitée de la mer pour l'observation de la couleur de l'océan depuis l'espace“. Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10010/document.

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La principale difficulté pour l'observation de la "couleur de l'océan" depuis l'espace est d'effectuer les corrections atmosphériques, c'est à dire extraire le signal provenant des océans du signal total largement dominé par la contribution de l'atmosphère. Dans ce cadre, des problèmes spécifiques liés aux capteurs satellitaires utilisés, ou aux conditions d'observations, peuvent apparaître. Dans le cas du capteur POLDER-3, nous avons diagnostiqué des défauts sur les produits marins grâce aux mesures in situ BOUSSOLE, notamment attribuables aux données d'entrée (de niveau 1), et de proposer plusieurs ajustements. Ces modifications ont abouti à une amélioration majeure de précision des produits, d'un facteur 1.5 à 2. De plus, le même algorithme de correction atmosphérique a été appliqué aux données du capteur MERlS, ce qui a permis de mettre en évidence ses propriétés de fonctionnement. Les algorithmes de correction atmosphérique existants sont également limités par la tâche brillante du rayonnement solaire réfléchi par la surface agitée de la mer (le sun glint), ne pouvant fonctionner lorsque ce signal est trop intense. Pour de nombreux capteurs (MERlS, MODIS ... ) ceci rend près de la moitié des observations aux latitudes subtropicales inutilisables. Nous proposons un algorithme, appelé POLYMER, conçu pour fonctionner sur l'ensemble du sun glint. Si le gain en couverture spatiale est spectaculaire, il se fait encore au détriment de la précision des produits. Néanmoins, cet algorithme montre qu'il est possible d'utiliser de données contaminées par le sun glint pour la couleur de l'océan, et ouvre de nouvelles perspective pour les applications futures
The main challenge for observing the”ocean colour” from space is to make the atmospheric correction which consists in extracting the marine signal from the measured dominated by the atmospheric scattering. In this context, we have studied specific problems that arise due to the quality of the sensor radiometry or to the viewing conditions. In the case of POLDER-3, we have used the in situ BOUSSOLE data to detect some problems, one of which can be attributed to a defect in the input (level1) data. We have made empirical corrections for these defects, resulting in an improvement of the accuracy of the marine reflectance products by a factor 1.5 to 2. Moreover, the same atmospheric correction algorithm was applied to the MERIS data to emphasize some of its features. The existing atmospheric correction algorithms are also limited by the sunglint, failing to retrieve marine parameters in the bright pattern of the sun reflected by the wavy sea surface. For many sensors (MERIS,MODIS...), this makes almost half of the observations at subtropical latitudes unusable, reducing the global coverage accordingly. We are presenting an original algorithm, called POLYMER, designed to make atmospheric correction over the whole sun glint pattern. The increase of spatial coverage is spectacular, while the accuracy on the retrieved marine parameters remains acceptable.This study shows that itis possible to retrieve the ocean colour in the sun glint contaminated areas and opens new opportunities for future applications
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Essalhi, Abdenacer. „Étude de la diffraction d'une onde électromagnétique par des surfaces apériodiques parfaitement conductrices. Application au calcul du renforcement des champs électromagnétiques par la surface d'une mer houleuse“. Clermont-Ferrand 2, 1990. http://www.theses.fr/1990CLF21206.

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La résolution des équations de Maxwell écrites sous forme covariante est faite dans un système de coordonnées non orthogonales adapté aux conditions aux limites. Les solutions du problème de la diffraction d'une onde électromagnétique plane par une surface rugueuse parfaitement conductrice sont obtenues par une méthode différentielle, conduisant à la recherche des valeurs propres et vecteurs propres. Les valeurs propres fournissent les directions des ondes diffractées et les vecteurs propres permettent de calculer les énergies diffractées. En outre nous avons adapté à notre problème une méthode de perturbation des conditions aux limites. Cette méthode est valable dans le cas de rugosités de faible hauteur par rapport à la longueur d'onde de l'onde incidente. Des résultats numériques sont présentés dans le cas d'une mer houleuse parfaitement conductrice. Pour représenter le profil de la surface de la mer, nous avons adopté un modèle périodique sinusoïdal
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Merlatti, Céline. „Etude de la dégradation de matrices organiques et des interfaces dans des systèmes de peinture : contribution à la maîtrise de leur durabilité en environnement humain“. Toulon, 2006. http://www.theses.fr/2006TOUL0011.

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Les plateformes navales sont soumises à un environnement naturel particulièrement agressif qui peut non seulement affecter les conditions opérationnelles des navires mais également générer des coûts d'entretien élevés. La protection contre la corrosion des navires de la Marine Nationale est souvent assurée par des revêtements organiques. La durabilité attendue des systèmes se situe autour de 15 ans. Aujourd'hui, la durée d'efficacité de la protection est inférieure ce qui nécessite des travaux de maintenance fréquents. Les objectifs de ce travail sont multiples : tout d'abord, évaluer la représentativité des essais de vieillissement réalisés en laboratoire vis-à-vis du vieillissement en milieu naturel ; ensuite, définir un cycle de vieillissement artificiel plus représentatif du vieillissement naturel ; puis, comprendre les facteurs qui sont déterminants dans les pertes de protection. A l'issue de ces travaux, un ou plusieurs traceur(s) de l'évolution des performances anticorrosion pourront donc être proposé(s). Les résultats présentés ici portent sur l'étude de trois systèmes anticorrosion industriels constitués de trois couches : finition - intermédiaire - primaire. L'épaisseur totale des revêtements étudiés est comprise entre 200 et 250 μm. Dans cette étude, chaque système anticorrosion est soumis à cinq vieillissements artificiels : Brouillard Salin (BS ISO 227), trois cycles normalisés (QUV ASTM G 53, ASTM D 5894 et ISO 20340) et un cycle innovant défini au laboratoire. Parallèlement, les échantillons sont exposés durant quatre ans sur trois sites de vieillissement naturel: d'une part, à Bandol, (83, France) de classe de corrosivité C3 et d'autre part, à Pipady (83, France) et Kure Beach (Caroline du Nord, USA), de classe de corrosivité C5M qui permettent d'associer les contraintes d'un climat chaud et ensoleillé à ceux d'une atmosphère marine. Après vieillissement, la combinaison de différentes techniques de caractérisation (Microscopie IRTF, pyrolyse couplée GC-MS, Analyse Mécanique Dynamique, Microdureté Vickers et MEB) permet d'étudier les évolutions physico-chimiques dans les différentes couches. L'évolution des propriétés d'interface substrat/revêtement est évaluée par des méthodes destructives (décapage et observations) et non destructives (Spectroscopie d'impédance électrochimique classique et locale, mesures de potentiel de surface). La comparaison des dégradations physiques et physico-chimiques observées après vieillissements naturel et artificiel sont différentes. La température joue un rôle déterminant dans la représentativité des cycles artificiels. Sur la base de ces résultats, un essai de vieillissement artificiel, plus représentatif des mécanismes de dégradation en milieu naturel marin, a pu être défini. De plus, les résultats obtenus ont permis de hiérarchiser l'impact des différentes contraintes d'agressivité des vieillissements sur la durabilité des systèmes. Les évolutions chimiques et physico-chimiques identifiées ne contrôlent pas spécifiquement les pertes de propriétés anticorrosion. Par contre, nous montrons que les contraintes internes générées lors des vieillissements par les cycles chaud/froid et séchage/humidité influencent directement les performances des systèmes
In the French Navy, organic coating systems are used to protect ships from corrosion. The service life requirements for protection are a long-term durability of 15 years. Today, the protection is insufficiently durable to meet the requirements, involving important maintenance cost. Thus, coating weatherability testing must be carried out to predict coating failures. The goal of this work is to, first, evaluate whether artificial test is reliable and representative of weathering, secondly, define a new reliable artificial test and finally, understand and identify loss of protection controlling factor. Three anticorrosive systems are studied. Each system presents three layers: topcoat – basecoat – primer. The total width is comprised between 200 and 250 μm. All samples are exposed to four different standard artificial weathering tests: a neutral salt spray test (NSS ISO 9227) and three cycles (QUV ASTM G53, ASTM D5894 and ISO 20340. Besides, the same samples are exposed to a natural weathering during four years in three different locations: Bandol, (83, France) classified as a C3 site, Pipady (83, France) and Kure Beach (North Caroline, USA), classified as C5M sites. Both Kure Beach and Pipady permit to expose coatings to high intensity sunlight in a marine atmosphere. After ageing, the rate of chemical and physico-chemical changes in each layer is followed using different characterisation methods (FTIR Microscopy, Pyrolysis – GC/MS, Dynamical Mechanical Analysis, Vickers Microhardness and SEM). Substrate/primer interface properties are studied by destructive method (the corroded area measurement in the scribing area beneath the coating) and non –destructive methods (Electrochemical Impedance Spectroscopy (EIS), Local EIS, surface potential measure). By comparing the kinds of chemical and physico-chemical changes in the different tests, it is possible to assess the validity of the accelerated tests. QUV ASTM G53, ASTM D5894 and ISO 20340 artificial cycles involve chemical processes which differ from those obtained after natural exposure. Here, the temperature is believed to be a key factor to explain such differences. On the bases of these results, a new cycle has been defined, more reliable. The variety of different weathering conditions permits to determine the more severe conditions in terms of degradation. Coating durability is not directly linked to physicochemical evolution that occurs in the coating. In fact, internal stresses developed during both temperature and moisture cycles control the coating performance
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Bücher zum Thema "Mer – Surfaces"

1

Eric, Marcus, Hrsg. Breaking the surface. London: Orion, 1995.

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Loire, René. La mer pour vaincre: Et le ciel aussi : des idées navalement incorrectes : essai. Houston, Texas: A. Ghosh, c1999., 1999.

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Vedligeholdelsesafdelingen, Denmark Vejdirektoratet, Hrsg. Målinger på hovedlandeveje med laser road surface tester, 1989: Analyse af sporkøringsmålinger. [Copenhagen]: Vejdirektoratet, Vedligeholdelsesafdelingen, 1990.

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4

United States. National Aeronautics and Space Administration., Hrsg. [Global surface-based cloud observation for ISCCP]: [final report, 18 Mar. 1989 - 30, Jun. 1994]. [Boulder, Colo: University of Colorado, Boulder, Dept. of Astrophysical, Planetary and Atmospheric Sciences, 1994.

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United States. National Aeronautics and Space Administration., Hrsg. [Global surface-based cloud observation for ISCCP]: [final report, 18 Mar. 1989 - 30, Jun. 1994]. [Boulder, Colo: University of Colorado, Boulder, Dept. of Astrophysical, Planetary and Atmospheric Sciences, 1994.

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United States. National Aeronautics and Space Administration., Hrsg. [Global surface-based cloud observation for ISCCP]: [final report, 18 Mar. 1989 - 30, Jun. 1994]. [Boulder, Colo: University of Colorado, Boulder, Dept. of Astrophysical, Planetary and Atmospheric Sciences, 1994.

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7

Masia, François. Atlas des anomalies du niveau de la mer et des courants géostrophiques de surface déduits de GEOSAT, novembre 1986-février 1989. Nouvelle-Calédonie: Centre ORSTOM de Nouméa, 1996.

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8

Rebelle, Michel. Sédimentologie, géochimie et palynologie du bassin évaporitique du Zechstein, à partir de données de sub-surface (mer du Nord, Hesse-R.F.A.). Paris: Laboratoire de géologie du Muséum, 1986.

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United States. National Aeronautics and Space Administration., Hrsg. Analysis of surfaces from the LDEF A0114, phase II: Semi-annual report on NAG1-1228 for the reporting period Mar. 1st - Aug. 31, 1992. [Washington, DC: National Aeronautics and Space Administration, 1992.

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Blunn, Gordon. Bearing surfaces. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199550647.003.007006.

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♦ Traditionally bearings were made from polyethylene and cobalt chrome. These bearings are still most commonly used for knee replacements. In hip replacements due to osteolysis caused by polyethylene wear alternative material combinations at the bearing surface are used♦ Highly cross linked plastics have been developed and have been shown to reduce wear. There are a number of different types available which differ in their performance♦ Metal on metal bearings first used in the 1960s have also been developed and show very low wear rates. These bearings are more susceptible to edge loading and the resulting metal ion release can result in adverse biological reactions leading to failure♦ Whilst ceramic on plastic surfaces have been used for a considerable amount of time the reduction in wear is not as great as with well functioning metal on metal bearings♦ Ceramic on ceramic bearings have been used for a considerable time and show even lower wear rates than metal on metal bearings. In the past there has been an incidence of catastrophic fracture of these bearings but developments in materials technology have considerably reduced these events.
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Buchteile zum Thema "Mer – Surfaces"

1

Pitolli, Francesca. „Neuroelectric Current Localization from Combined EEG/MEG Data“. In Curves and Surfaces, 562–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-27413-8_37.

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Fletcher, Colin. „Men in the middle: a reformulation of the thesis“. In Beneath the Surface, 3–14. London: Routledge, 2023. http://dx.doi.org/10.4324/9781003459927-2.

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Lin, L., G. S. Blackman und R. R. Matheson. „Micromechanical Characterization of Scratch and Mar Behavior of Automotive Topcoats“. In Microstructure and Microtribology of Polymer Surfaces, 428–38. Washington, DC: American Chemical Society, 1999. http://dx.doi.org/10.1021/bk-2000-0741.ch027.

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Gohin, F. „Analyse Structurale de La Temperature de Surface de La Mer“. In Geostatistics, 433–44. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-015-6844-9_33.

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Andronikou, Savvas. „Brain Surface Anatomy and Functional Regions“. In See Right Through Me, 101–16. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-23893-2_5.

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Ridgway, John P. „Improving SNR with Surface Coils and Array Coils“. In Cardiovascular MR Manual, 77–80. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-20940-1_9.

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Plein, Sven, John P. Greenwood und John P. Ridgway. „Improving SNR with Surface Coils and Array Coils“. In Cardiovascular MR Manual, 83–86. London: Springer London, 2010. http://dx.doi.org/10.1007/978-1-84996-362-6_9.

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MAHFOUF, Jean-François. „Les variables de surface“. In Satellites pour les sciences de l’atmosphère 2, 51–72. ISTE Group, 2025. https://doi.org/10.51926/iste.9141.ch3.

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La prévision numérique du temps nécessite la spécification précise d’un certain nombre de variables caractérisant les surfaces terrestres et océaniques. La télédétection satellitaire permet d’accéder à certaines d’entre elles, comme la température de surface, le vent à la surface de la mer, l’humidité des sols et certaines propriétés de la végétation ou de la neige.
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McEvoy, Andrew. „Dermoid and epidermoid cysts“. In Oxford Textbook of Neurological Surgery, herausgegeben von Ramez W. Kirollos, Adel Helmy, Simon Thomson und Peter J. A. Hutchinson, 197–204. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780198746706.003.0016.

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Dermoid and epidermoid cysts are important intracranial developmental lesions. They are commonly derived from retained surface ectoderm trapped by two fusing neuroectodermal surfaces during neural tube closure, and are also termed congenital ectodermal inclusion cysts. Occasionally epidermoid cysts are acquired lesions derived from iatrogenic implantation of surface ectoderm (termed implantation dermoids). Dermoid cysts are rare, usually midline lesions that present early; these include dermoid structures and may rupture, causing meningitis. Epidermoids are usually lateral, slightly more common, and present later. Radiologically these lesions are characterized by restricted diffusion on MRI which distinguishes them from arachnoid cysts. Treatment is usually surgical with complete or subtotal resection of the cyst, the need for long-term follow-up is controversial.
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Schissel, Scott L. „Pleural Disease“. In The Brigham Intensive Review of Internal Medicine, 325–33. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199358274.003.0032.

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The pleural space is lined by the parietal and visceral pleurae. The parietal pleura covers the inner surface of the thoracic cavity, including the mediastinum, diaphragm, and ribs. The visceral pleura covers all lung surfaces, including the interlobar fissures. The right and left pleural spaces are separated by the mediastinum. The pleural space contains a relatively small amount of fluid, approximately 10 mL on each side (approximately 0.13 mL/kg of body weight). The pleural space plays an important role in respiration by coupling the movement of the chest wall with that of the lungs in two ways. First, a relative vacuum in the space keeps the visceral and parietal pleurae in close proximity. Second, the small volume of pleural fluid serves as a lubricant to facilitate movement of the pleural surfaces against each other in the course of respirations. The small volume of fluid is maintained through the balance of hydrostatic and oncotic pressure and lymphatic drainage, a disturbance of which may lead to pathology. A pleural effusion is defined as an abnormal amount of pleural fluid accumulation in the pleural space and is the result of an imbalance between excessive pleural fluid formation and pleural fluid absorption.
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Konferenzberichte zum Thema "Mer – Surfaces"

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You, Jiahao, Ziye Jia, Chao Dong, Qihui Wu und Zhu Han. „Generative AI-Enhanced Cooperative MEC of UAVs and Ground Stations for Unmanned Surface Vehicles“. In 2025 59th Annual Conference on Information Sciences and Systems (CISS), 1–6. IEEE, 2025. https://doi.org/10.1109/ciss64860.2025.10944752.

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Lu, Pengfei, und Makoto Ando. „Correction term of MER for PO surface-to-line integral reduction for curved surfaces“. In 2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium). IEEE, 2014. http://dx.doi.org/10.1109/usnc-ursi.2014.6955552.

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Geranpour, Mansoureh, Zahra Emam-Djomeh und Gholamhassan Asadi. „Microencapsulation of pumpkin seed oil by spray dryer under various process conditions and determination of the optimal point by RSM“. In 21st International Drying Symposium. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/ids2018.2018.7332.

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The objective of this research was to microencapsulating the pumpkin seed oil (PSO) by the spray dryer and also investigating the effects of some process conditions on physicochemical properties of PSO microparticles. Inlet drying air temperature (140-180 ͦC), aspirator rate (55-75%), and peristaltic pump rate (5-15%) effects were studied. Moisture content (%W.b.), Microencapsulation Efficiency (MEE, %) and Peroxide value (POV, meq/kg sample) considered as model responses. Consequently, the ideal drying state for microencapsulation of PSO as a result of optimizing by Response Surface Methodology (RSM) determined with the aim of minimizing the Moisture content and POV and maximizing the MEE. Keywords: Microencapsulation; spray dryer; pumpkin seed oil; optimization; RSM.
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Borello, Domenico, Lucio Cardillo, Alessandro Corsini, Giovanni Delibra, Franco Rispoli, Alessandro Salvagni, A. G. Sheard und Paolo Venturini. „Modelling of Particle Transport, Erosion and Deposition in Power Plant Gas Paths“. In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57984.

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Flow evolving in turbomachinery applications is turbulent and laden with particles, such as dust, ash, dirt, etc. This would affect the behaviour of the turbine components given that solid particles can impact and then bounce off, deposit or erode their surfaces. Erosion and deposition phenomena may seriously affect the components performance, because they alter the blade profile and hence the flow field. It is thus clear that the prediction of these phenomena would be of great help form both design optimization and maintenance of turbomachinery. Besides experiments, in the last decade CFD became one of the main tool for studying flow evolution within turbine components, phenomena that involve them, and prediction of problems. In particle-laden flows, CFD is used to simulate the flow field, but also solid particle transport and dispersion, impact mechanics, adhesion or rebound, and erosion. Several approaches can be used depending on the kind of application studied and information expected. Particle transport can be simulated adopting a single or cluster of particle tracking approach (Crowe et al, 2006). Since to have a statistically independent results a large number of simulated particles is needed, the for-mer approach can be used when the domain size is not too large; moreover the instantaneous flow field is needed, otherwise turbulent dispersion of particles has to be accounted for. The cluster of particles approach (i.e., Particle Cloud Tracking model, Baxter 1989) overcomes some of these problems, since it usually uses a model for particle dispersion, computing very few trajectories to simulate a large number of particles. Particle impact/rebound and deposit/erosion are modelled using one of the available choice. For instance, impact mechanics can be modelled according to the Johnson-Kendall-Roberts theory (1971) if the particle temperature is not large enough to modify the physical properties of the particles, or the Thornton and Ning variation (1997). When the effect of temperature becomes relevant, a temperature based sticking model is used, such as that of Walsh et al. (1990). Erosion can be studied according to the model of Tabackof (1979). Aim of this study is showing how CFD can be used to simulate particle deposition/erosion in all the components of a turbine (i.e. fan, turbine, compressor), and predict the most critical regions of a given component. This will be done introducing the numerical models used for some applications, describing reference test cases, and showing/discussing results.
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Kang, Kyungho, und Pranav Shrotriya. „Surface Stress Development Associated With Hybridization of Monomolecular DNA Film“. In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12011.

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Surface stress changes associated with hybridization of surface immobilized DNA molecules are measured. A novel interferometry technique employing two adjacent micromachined cantilevers a sensing/reference pair is used to measure the surface stress development. Measurement approach relies on coating the sensing cantilever with single stranded DNA (30-mer Adenine (poly A)) and reference cantilever with hybridized DNA. The sensing/reference pair is exposed to varying concentrations of complimentary DNA strand (30-mer Thymine (Poly T)) and differential deflection of sensing cantilever with respect to reference is measured to determine the change in surface stress. Experimental results indicate that surface stress develops only on exposure to complimentary strands (specific binding) and is not affected by exposure to other single stranded DNA (non-specific binding). Varying the poly T concentration from 0.1 to 1.0 μM results in a linear increase of the surface stress changes from 40 to 110 mN/m during DNA hybridization. Surface stress development starts as soon as the complementary poly T is introduced in the fluid cell and reaches a stable value within 15 minutes of injection time.
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Staab, Michael S., Jennifer A. Herman, Kevin Reich, Vishnu Sridhar und Robert W. Nelson. „MER Opportunity Dust-Storm Recovery Operations and Implications for Future Mars Surface Missions“. In 2020 IEEE Aerospace Conference. IEEE, 2020. http://dx.doi.org/10.1109/aero47225.2020.9172528.

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Bonnin-Pascual, Francisco, und Alberto Ortiz. „An AdaBoost-based approach for coating breakdown detection in metallic surfaces“. In Automation (MED 2011). IEEE, 2011. http://dx.doi.org/10.1109/med.2011.5983121.

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Yang, Bo, Xueyao Zhang, Zhiwen Yu, Xuelin Cao, Chongwen Huang, George C. Alexandropoulos, Yan Zhang, Mérouane Debbah und Chau Yuen. „Reconfigurable Intelligent Computational Surfaces for MEC-Assisted Autonomous Driving Networks“. In 2024 IEEE Wireless Communications and Networking Conference (WCNC). IEEE, 2024. http://dx.doi.org/10.1109/wcnc57260.2024.10570740.

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Gong, Wenyong, Minghao Guo und Tieru Wu. „Computing ruled surfaces using weighted graph“. In 2011 International Conference on Mechatronic Science, Electric Engineering and Computer (MEC). IEEE, 2011. http://dx.doi.org/10.1109/mec.2011.6025638.

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Rodriguez, L., Y. Katakai, M. Oishi und M. Ando. „PO-surface to MER-line integral reduction -Local error criteria in terms of Fresnel region indices-“. In 2008 IEEE Antennas and Propagation Society International Symposium and USNC/URSI National Radio Science Meeting. IEEE, 2008. http://dx.doi.org/10.1109/aps.2008.4619471.

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Berichte der Organisationen zum Thema "Mer – Surfaces"

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Yermiyahu, Uri, Thomas Kinraide und Uri Mingelgrin. Role of Binding to the Root Surface and Electrostatic Attraction in the Uptake of Heavy Metal by Plants. United States Department of Agriculture, 2000. http://dx.doi.org/10.32747/2000.7586482.bard.

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The principal accomplishment of the research supported by BARD was progress toward a comprehensive view of cell-surface electrical effects (both in cell walls [CWs] and at plasma membrane [PM] surfaces) upon ion uptake, intoxication, and amelioration. The research confirmed that electrostatic models (e.g., Gouy-Chapman-Stern [G-C-S]), with parameter values contributed by us, successfully predict ion behavior at cell surfaces. Specific research objectives 1. To characterize the sorption of selected heavy metals (Cu, Zn, Pb, Cd) to the root PM in the presence of other cations and organic ligands (citric and humic acids). 2. To compute the parameters of a G-C-S model for heavy-metal sorption to the root PM. 3. To characterize the accumulation of selected heavy metals in various plant parts. 4. To determine whether model-computed ion binding or ion activities at root PM surfaces predict heavy-metal accumulation in whole roots, root tips, or plant shoots. 5. To determine whether measured ion binding by protoplast-free roots (i.e., root CWs) predicts heavy-metal accumulation in whole roots, root tips, or plant shoots. 6. To correlate growth inhibition, and other toxic responses, with the measured and computed factors mentioned above. 7. To determine whether genotypic differences in heavy-metal accumulation and toxic responses correlate with genotypic differences in parameters of the G-C-S model. Of the original objectives, all except for objective 7 were met. Work performed to meet the other objectives, and necessitated on the basis of experimental findings, took the time that would have been required to meet objective 7. In addition, work with Pb was unsuccessful due to experimental complications and work on Cd is still in progress. On the other hand, the uptake and toxicity of the anion, selenate was characterized with respect to electrostatic effects and the influences of metal cations. In addition, the project included more theoretical work, supported by experimentation, than was originally planned. This included transmembrane ion fluxes considered in terms of PM-surface electrical potentials and the influence of CWs upon ion concentrations at PM surfaces. A important feature of the biogeochemistry of trace elements in the rhizosphere is the interaction between plant-root surfaces and the ions present in the soil solution. The ions, especially the cations, of the soil solution may be accumulated in the aqueous phases of cell surfaces external to the PMs, sometimes referred to as the "water free space" and the "Donnan free space". In addition, ions may bind to the CW components or to the PM surface with variable binding strength. Accumulation at the cell surface often leads to accumulation in other plant parts with implications for the safety and quality of foods. A G-C-S model for PMs and a Donnan-plus-binding model for CWs were used successfully to compute electrical potentials, ion binding, and ion concentration at root-cell surfaces. With these electrical potentials, corresponding values for ion activities may be computed that are at least proportional to actual values also. The computed cell-surface ion activities predict and explain ion uptake, intoxication, and amelioration of intoxication much more accurately than ion activities in the bulk-phase rooting medium.
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Ritsche, M. T. ARM mobile facility surface meteorology (MET) handbook. Office of Scientific and Technical Information (OSTI), April 2006. http://dx.doi.org/10.2172/925320.

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J.A. Ziegler. CLASSIFICATION OF THE MGR SURFACE ENVIRONMENTAL MONITORING SYSTEM. Office of Scientific and Technical Information (OSTI), August 1999. http://dx.doi.org/10.2172/860256.

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Hanson, A. E. H., A. L. Bobst, G. Abdo, J. I. LaFave und M. Sutherland. Managed Aquifer Recharge (MAR): An initial hydrogeologic screening for surface infiltration suitability in Montana. Montana Bureau of Mines and Geology, Oktober 2024. http://dx.doi.org/10.59691/sxsp1714.

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As an initial screening to identify areas in Montana that may be appropriate for the MAR surface infiltration method, a suitability analysis was conducted using a geographic information system (GIS) and multi-criteria decision analysis (MCDA). Four hydrogeologic criteria were chosen for the suitability analysis: geology/aquifer, depth to groundwater, soil permeability, and topographic slope. The final suitability map is provided as a plate and as an interactive WebApp that identifies locations that appear hydrogeologically suitable for MAR surface infiltration methods.
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Riede, Wolfgang. Surface Evaluation of Laser-Irradiated Coated/Uncoated MIR Optronic Components. Fort Belvoir, VA: Defense Technical Information Center, Dezember 2000. http://dx.doi.org/10.21236/ada410688.

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Braams, Baastian, und Christian Hill. Plasma-wall Interaction with Reduced-activation Steel Surfaces in Fusion Devices. IAEA Nuclear Data Section, März 2018. http://dx.doi.org/10.61092/iaea.basb-m78v.

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Seven experts in the field of plasma-wall interaction on steel surfaces together with IAEA staff met at IAEA Headquarters 16–18 October 2017 for the Second Research Coordination Meeting of an IAEA Coordinated Research Project on Plasma-wall Interaction with Reduced-activation Steel Surfaces in Fusion Devices. They described progress with their research since the previous project meeting in December 2015, discussed open issues and made plans for continued coordinated research during the remaining years of the project. The proceedings of the meeting are summarized in this report.
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Hill, Christian. Plasma-wall Interaction with Reduced-activation Steel Surfaces in Fusion Devices. IAEA Nuclear Data Section, März 2019. http://dx.doi.org/10.61092/iaea.nw6r-gvbe.

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Eight experts in the field of plasma-wall interaction on steel surfaces together with IAEA staff met at IAEA Headquarters 25 – 27 March 2019 for the Third Research Coordination Meeting of an IAEA Coordinated Research Project on Plasma-wall Interaction with Reduced-activation Steel Surfaces in Fusion Devices. They described progress with their research since the previous project meeting in October 2017, discussed open issues and made plans for a final project report giving details of outcomes of the CRP and for future research work relevant to the project. The proceedings of the meeting are summarized in this report.
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Tawfik, Aly, Deify Law, Juris Grasis, Joseph Oldham und Moe Salem. COVID-19 Public Transportation Air Circulation and Virus Mitigation Study. Mineta Transportation Institute, Juni 2022. http://dx.doi.org/10.31979/mti.2021.2036.

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COVID-19 may have forever changed our world. Given the limited space and air circulation, potential infections on public transportation could be concerningly high. Accordingly, this study has two objectives: (1) to understand air circulation patterns inside the cabins of buses; and (2) to test the impact of different technologies in mitigating viruses from the air and on surfaces inside bus cabins. For the first objective, different devices, metrics and experiments (including colored smoke; videotaping; anemometers; pressure differentials; particle counts; and 3D numerical simulation models) were utilized and implemented to understand and quantify air circulation inside different buses, with different characteristics, and under different operating conditions (e.g. with windows open and shut). For the second objective, three different live prokaryotic viruses were utilized: Phi6, MS2 and T7. Various technologies (including positive pressure environment inside the cabin, HEPA filters with different MERV ratings, concentrated UV exposure with charged carbon filters in the HVAC systems, center point photocatalytic oxidation technology, ionization, and surface antiviral agents) were tested to evaluate the potential of mitigating COVID-19 infections via air and surfaces in public transportation. The effectiveness of these technologies on the three live viruses was tested in both the lab and in buses in the field. The results of the first objective experiments indicated the efficiency of HVAC system designs, where the speed of air spread was consistently much faster than the speed of air clearing. Hence, indicating the need for additional virus mitigation from the cabin. Results of the second objective experiments indicated that photocatalytic oxidation inserts and UVC lights were the most efficient in mitigating viruses from the air. On the other hand, positive pressure mitigated all viruses from surfaces; however, copper foil tape and fabrics with a high percentage of copper mitigated only the Phi6 virus from surfaces. High-temperature heating was also found to be highly effective in mitigating the different viruses from the vehicle cabin. Finally, limited exploratory experiments to test possible toxic by-products of photocatalytic oxidation and UVC lights inside the bus cabin did not detect any increase in levels of formaldehyde, ozone, or volatile organic compounds. Implementation of these findings in transit buses, in addition to the use of personal protective equipment, could be significantly valuable for protection of passengers and drivers on public transportation modes, possibly against all forms of air-borne viruses.
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Tawfik, Aly, Deify Law, Juris Grasis, Joseph Oldham und Moe Salem. COVID-19 Public Transportation Air Circulation and Virus Mitigation Study. Mineta Transportation Institute, Juni 2022. http://dx.doi.org/10.31979/mti.2022.2036.

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COVID-19 may have forever changed our world. Given the limited space and air circulation, potential infections on public transportation could be concerningly high. Accordingly, this study has two objectives: (1) to understand air circulation patterns inside the cabins of buses; and (2) to test the impact of different technologies in mitigating viruses from the air and on surfaces inside bus cabins. For the first objective, different devices, metrics and experiments (including colored smoke; videotaping; anemometers; pressure differentials; particle counts; and 3D numerical simulation models) were utilized and implemented to understand and quantify air circulation inside different buses, with different characteristics, and under different operating conditions (e.g. with windows open and shut). For the second objective, three different live prokaryotic viruses were utilized: Phi6, MS2 and T7. Various technologies (including positive pressure environment inside the cabin, HEPA filters with different MERV ratings, concentrated UV exposure with charged carbon filters in the HVAC systems, center point photocatalytic oxidation technology, ionization, and surface antiviral agents) were tested to evaluate the potential of mitigating COVID-19 infections via air and surfaces in public transportation. The effectiveness of these technologies on the three live viruses was tested in both the lab and in buses in the field. The results of the first objective experiments indicated the efficiency of HVAC system designs, where the speed of air spread was consistently much faster than the speed of air clearing. Hence, indicating the need for additional virus mitigation from the cabin. Results of the second objective experiments indicated that photocatalytic oxidation inserts and UVC lights were the most efficient in mitigating viruses from the air. On the other hand, positive pressure mitigated all viruses from surfaces; however, copper foil tape and fabrics with a high percentage of copper mitigated only the Phi6 virus from surfaces. High-temperature heating was also found to be highly effective in mitigating the different viruses from the vehicle cabin. Finally, limited exploratory experiments to test possible toxic by-products of photocatalytic oxidation and UVC lights inside the bus cabin did not detect any increase in levels of formaldehyde, ozone, or volatile organic compounds. Implementation of these findings in transit buses, in addition to the use of personal protective equipment, could be significantly valuable for protection of passengers and drivers on public transportation modes, possibly against all forms of air-borne viruses.
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Grönbäck, Anna-Maria, Tobias Andersson Granberg und Niki Matinrad. Tillämpningar av modern teknik inom räddning : möjligheter och framtida frågeställningar. Linköping: Linköping University Electronic Press, Oktober 2024. http://dx.doi.org/10.3384/9789180758468.

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Denna rapport ger en översikt över forskning och erfarenheter gällande räddningsinsatser där nya tekniker har använts, eller skulle kunna användas, vid såväl faktiska insatser som vid övning. Via en litteraturstudie, kompletterad med intervjuer med personer som är verksamma i projekt inom området, identifierades utmaningar och potential med modern teknik inom räddning. De olika teknologierna kategoriserades som Unmanned aerial/ground/surface vehicles (UXV), Artificiell intelligens (AI), Extended reality (XR, vilket inkluderar bland annat virtual och augmented reality), Kommunikationer, Sensorer, Robotar och Övrigt.Inom området artificiell intelligens för räddning behövs projekt som kan ta fram data av god kvalitet för att träna AI-modeller inom olika räddningstillämpningar (till exempel identifiering av skogsbrand, eller eftersök av person) i Sveriges varierande miljöer. Dessutom måste data och modeller valideras tillsammans med praktiker och förankras i räddningsverksamheten. Genom att utbilda responspersonal i principerna för maskininlärning kan användbarheten öka och risken för felaktiga resultat och tolkningar minskas.Teknikutvecklingen går fort medan relaterad metodutveckling och utvärdering ligger efter. För effektiv implementering av ny teknik är det viktigt att, tillsammans med användarna, undersöka vilka behov räddningstjänsten har och att ta fram metoder och modeller för hur nyttan med den nya tekniken ska utvärderas. Vidare måste den nya tekniken integreras med nuvarande arbetsmetoder, och modeller och metoder för effektiv gemensam resursanvändning av såväl nya som befintliga resurser måste utvecklas. Många mindre organisationer har svårt att själva driva denna typ av större utvecklingsprojekt, men skulle kunna hjälpas av administrativt stöd, till exempel från Myndigheten för samhällsskydd och beredskap (MSB).Säkra, robusta kommunikationsmöjligheter vid räddningsinsatser är ett viktigt område, och vidare forskning behövs för att möjliggöra detta med hjälp av drönare (UAS) i såväl fjällmiljö som till havs. Dessutom behövs flera projekt som kan tillhandahålla säkra lösningar för kommunikation och datasäkerhet inom räddning, och forskning kring hur relevant informationsdelning mellan olika aktörer kan möjliggöras. Användandet av UAS inom räddning börjar bli etablerat, och det finns potential i att utforska möjligheten med delat användande, till exempel hur drönare med andra tillämpningsområden (exempelvis matleveranser) skulle kunna bidra i räddningsinsatser. Många av de undersökta teknologierna kan användas kombinerat, till exempel kan en AI-modell tolka bilder som fångas av en drönare. Hur olika teknologier kan kombineras är ett område med fortsatt stor potential. Det saknas också vetenskapliga studier över potentialen av användningen av exoskelett inom räddning.
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