Sample records for zata poutziouris kosmas
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A Genome-wide Breast Cancer Scan in African Americans
2012-06-01
Vuorinen A, Kaaks R, Ko YD, Kolonel LN, Konstantopoulou I, Kosma VM, Kulkarni S, Lambrechts D, Lee AM, Marchand LL, Lesnick T, Liu J, Lindstrom S...Mannermaa A, Margolin S, Martin NG, Miron P, Montgomery GW, Nevanlinna H, Nickels S, Nyante S, Olswold C, Palmer J, Pathak H, Pectasides D, Perou CM...Vuorinen A, Kaaks R, Ko YD, Kolonel LN, Konstantopoulou I, Kosma VM, Kulkarni S, Lambrechts D, Lee AM, Marchand LL, Lesnick T, Liu J, Lindstrom S
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1983-03-01
var. cerifera L. Wax myrtle Onagraceae *Ludiigia aZata Ell. W. - r-priurose Oenothera frticoea L. drops 0. hisniflsa Nuttall Evening primrose... Orchidaceae Spiranthee cernua ver. odorata Nodding ladies’ (Nuttall) Correll. tresses Passiflorarese *PassifZora lutea L. Passion-flower Phytolacaceat POytoZaca
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Obama Kennedy Space Center Visit
2010-04-14
President Barack Obama, left, exits of Air Force One with, from left, Representative US Representative Suzanne M. Kosmas (D - FL), U.S Senator Bill Nelson (D-FL), NASA Administrator Charles Bolden, and Apollo 11 Astronaut Buzz Aldrin after landing at the NASA Kennedy Space Center in Cape Canaveral, Fla. on Thursday, April 15, 2010. Obama visited Kennedy to deliver remarks on the bold new course the administration is charting to maintain U.S. leadership in human space flight. Photo Credit: (NASA/Bill Ingalls)
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NASA Astrophysics Data System (ADS)
Ángel González Peñaloza, Félix; Cerdà, Artemi
2014-05-01
The Enviromental Sensitive Areas (ESAs) approach to study the Land Degradation is a methodology developed by professor Costas Kosmas et al., (1999) to map environmental sensitive areas and then the impact of Land Degradation and desertification on Mediterranean Type Ecosystems (Salvati et al., 2013). This methodology has been applied mainly to the Mediterranean Belt (Lavado Contador et al., 2009), but other authors adapted the methodology to other climatic regions (Izzo et al., 2013). The ESAs methodology allows mapping changes in the distribution of the sensitive areas to Desertification as a consequence of biophysical or human chances. In the Mediterranean countries of Europe, especially Spain, suffered a dramatic change due to the application of the European Common Agricultural Policies (CAP) after 1992. The objective of the CAP was to implemented policies to improve the environmental conditions of agricultural land. This target is especially relevant in Mediterranean areas of Spain, mainly the South and the East of the country. An Environmental Sensitive Area (ESAs) model (Kosmas et al., 2009) was implemented using Geographical Information System (GIS) tools, to identify, assess, monitor and map the levels of sensitivity to land degradation in the Canyoles river watershed, which is a representative landscape of the Mediterranean belt in Eastern Spain The results show that it was found that after the implementation of CAP, the most sensitive areas have expanded. This increase in degraded areas is driven by the expansion of commercial and chemically managed crops that increased the soil erosion (Cerdà et al., 2009) and that few soil conservation strategies were applied (Giménez Morera et al., 2010). Another factor that triggered Desertification processes is the increase in the recurrencesof forest fires as a consequence of land abandonment (Cerdà and Lasanta, 2005; Cerdà and Doerr, 2007). This contributed to an increase of scrubland. Our research show an increase in the rangeland vegetation that is dominated by scrubland, meanwhile the woodlands are reduced. Circa 50 % of the land that was classified as "Critical" to land degradation after 1985 had been previously classified as "Non-affected". However, not all changes occurred in the Cànyoles watershed are characterized by a negative change; i.e., 82 % of the land has turned from "Critical" values to "Non- sensitive" to land degradation between mid-20th century and recent times. We found this negative trend to be having been caused by the removal of those crops that are most sensitive to land degradation, such as rain-fed crops, and that are mainly located in the west of the studied watershed. Similar findings were found by Zema et al., (2012) when applying the AnnAGNPS model to the agriculture land in Belgiums, Prokop and Poreba (2012) to the India, Miao e t al., (2012) in China and Haile and Fetene (2012) in Ethiopia: man made changes in the landscape that trigger land degradation processes.. Acknowledgements This research was undertaken in the frame of the 7FP project LEDDRA - Land Ecosystem Degradation and Desertification: Assessing the Fit of Responses - ENV, 2009.2.1.3.2. We thank professor Costas Kosmas for his guidance. References Cerdà, A., Doerr, S.H. 2007. Soil wettability, runoff and erodibility of major dry-Mediterranean land use types on calcareous soils. Hydrological Processes, 21, 2325-2336. doi: 10.1016/j.catena.2008.03.010. Cerdà, A., Giménez-Morera, A. y Bodí, M.B. 2009. Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34, 1822-1830. DOI: 10.1002/esp.1889 Cerdà, A., Lasanta, A. 2005. Long-term erosional responses after fire in the Central Spanish Pyrenees: 1. Water and sediment yield. Catena, 60, 59-80. Giménez Morera, A., Ruiz Sinoga, J.D. y Cerdà, A. 2010. The impact of cotton geotextiles on soil and water losses in Mediterranean rainfed agricultural land. Land Degradation and Development , 210- 217. DOI: 10.1002/ldr.971. Haile, G.W., and Fetene, M. 2012. Assessment of soil erosion hazard in Kilie catchment, East Shoa, Ethiopia. Land Degradation & Development, 23 (3): 293-306. Miao, C. Y., Yang, L., Chen, X. H., Gao, Y. 2012. The vegetation cover dynamics (1982-2006) in different erosion regions of the Yellow River Basin, China. Land Degradation & Development, 23: 62- 71. DOI 10.1002/ldr.1050 Izzo, M., Araujo, N., Aucelli, P. P. C., Maratea, A., and Sánchez, A. 2013. Land sensitivity to Desertification in the Dominican Republic: an adaptation of the ESA methodology. Land Degradation & Development, 24: 486- 498. DOI 10.1002/ldr.2241 Kosmas, C., Ferrara, A., Briassouli, H., Imeson, A., 1999. Methodology for mapping Environmentally Sensitive Areas (ESAs) to Desertification. In: Kosmas, C., Kirkby, M., Geeson, N. (Eds.), The Medalus project: Mediterranean desertification and land use. Manual of key indicator of desertification and mapping environmentally sensitive areas to desertification. European Union, 31-47. Lavado Contador, J.F., Schnabel, S., Gómez Gutiérrez, A., Pulido Fernández, M., 2009. Mapping sensitivity to land degradation in Extremadura, SW Spain. Land Degradation and Development 20, 129-144. Prokop, P., Poreba, G. J. 2012. Soil erosion associated with an upland farming system under population pressure in Northeast India. Land Degradation & Development, 23: 310- 321. DOI 10.1002/ldr.2147 Salvati, L., Zitti, M., Perini, L. 2013. Fifty years on: long-term patterns of land sensitivity to desertification in Italy. Land Degradation and Development DOI: 10.1002/ldr.2226 Science 61, 174-185. Similar findings were found by Zema et al., (2012) when applying the AnnAGNPS model to the agriculture land in Belgiums, Prokop and Poreba (2012) to the India, Miao e t al., (2012) in China and Haile and Fetene (2012) in Ethiopia: man made changes in the landscape that trigger land degradation processes.. Zema, D. A., Bingner, R. L., Denisi, P., Govers, G., Licciardello, F., Zimbone, S. M. 2012. Evaluation of runoff, peak flow and sediment yield for events simulated by the AnnAGNPS model in a belgian agricultural watershed. Land Degradation & Development, 23: 205- 215. DOI 10.1002/ldr.1068
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Micromechanical Waveguide Mounts for Hot Electron Bolometer Terahertz Mixers
NASA Astrophysics Data System (ADS)
Brandt, Michael; Jacobs, Karl; Honingh, C. E.; Stodolka, Jörg
The superior beam matching of waveguide horn antennas to a telescope suggests using waveguide mounts even at THz-frequencies. In contrast to the more common quasi-optical (substrate lens) designs, the exceedingly small dimensions of the waveguide require novel micro-mechanical fabrication technologies. We will present a novel fabrication scheme for 1.9 THz waveguide mixers for SOFIA. Hot Electron Bolometer devices (HEB) are fabricated on 2 μm thick Si3N4 membrane strips. The strips are robust enough to be mounted on a separately fabricated Si support frame using an adapted flip-chip technology. Mounted onto the frame, the devices can be easily positioned and glued into a copper waveguide mount. Further developments regarding micro-mechanical processes to fabricate this copper waveguide mount and the receiving horn antenna will be presented, as well as the KOSMA Micro Assembly Station and its capabilities to handle mixer substrates.
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2009-01-26
CAPE CANAVERAL, Fla. – Representatives from NASA, Lockheed Martin, Space Florida and the state of Florida participate in a ceremony at NASA's Kennedy Space Center in Florida to mark the completion of renovations on the historic Operations and Checkout Building high bay for use by the Constellation Program. At center, U.S. Rep. Suzanne Kosmas and Lt. Governor Jeff Kottcamp listen to Richard Harris, with Lockheed Martin, describe some of the hardware that will be used in the building. Originally built to process space vehicles in the Apollo era, the building will serve as the final assembly facility for the Orion crew exploration vehicle. Orion, America's future human spaceflight vehicle, will be capable of transporting four crew members to the moon and later will support crew transfers to Mars. The Orion spacecraft also will be used to transport crew members to the International Space Station after space shuttles are retired in 2010. The first operational launch of Orion atop an Ares I rocket is planned for 2015. Photo credit: NASA/Dimitri Gerondidakis
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2009-05-27
CAPE CANAVERAL, Fla. – Gathering on stage for the groundbreaking ceremony for the joint NASA and Florida Power & Light, or FPL, solar power project at NASA's Kennedy Space Center are Florida Rep. Bill Posey, Eric Draper, deputy director of Audubon of Florida, Sen. Bill Nelson, Florida Rep. Suzanne Kosmas, Armando Olivera, president and CEO of FPL, Center Director Bob Cabana and Pam Rauch, vice president of External Affairs for FPL. FPL, Florida's largest electric utility, will build and maintain two solar photovoltaic power generation systems at Kennedy. One will produce an estimated 10 megawatts of emissions-free power for FPL customers, which is enough energy to serve roughly 1,100 homes. The second is a one-megawatt solar power facility that will provide renewable energy directly to Kennedy. The FPL facilities at NASA will help provide Florida residents and America's space program with new sources of clean energy that will cut reliance on fossil fuels and improve the environment by reducing greenhouse gas emissions. The one megawatt facility also will help NASA meet its goal for use of power generated from renewable energy. Photo credit: NASA/Kim Shiflett
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2009-05-27
CAPE CANAVERAL, Fla. – Armando Olivera, president and CEO of Florida Power & Light, or FPL, speaks to guests at the groundbreaking ceremony for the joint NASA and FPL solar power project at NASA's Kennedy Space Center. Others on the stage are, from left, Ed Smeloff with SunPower Corporation, Florida Rep. Suzanne Kosmas, Sen. Bill Nelson, Center Director Bob Cabana, Florida Rep. Bill Posey, Eric Draper, deputy director of Audubon of Florida, and Pam Rauch, vice president of External Affairs for FPL. FPL, Florida's largest electric utility, will build and maintain two solar photovoltaic power generation systems at Kennedy. One will produce an estimated 10 megawatts of emissions-free power for FPL customers, which is enough energy to serve roughly 1,100 homes. The second is a one-megawatt solar power facility that will provide renewable energy directly to Kennedy. The FPL facilities at NASA will help provide Florida residents and America's space program with new sources of clean energy that will cut reliance on fossil fuels and improve the environment by reducing greenhouse gas emissions. The one megawatt facility also will help NASA meet its goal for use of power generated from renewable energy. Photo credit: NASA/Kim Shiflett
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2009-05-27
CAPE CANAVERAL, Fla. – Pam Rauch, vice president of External Affairs for Florida Power & Light, or FPL, speaks to guests at the groundbreaking ceremony for the joint NASA and FPL solar power project at NASA's Kennedy Space Center. Others on the stage are Ed Smeloff with SunPower Corporation, Florida Rep. Suzanne Kosmas, Sen. Bill Nelson, Center Director Bob Cabana, Armando Olivera, president and CEO of FPL, Florida Rep. Bill Posey and Eric Draper, deputy director of Audubon of Florida. FPL, Florida's largest electric utility, will build and maintain two solar photovoltaic power generation systems at Kennedy. One will produce an estimated 10 megawatts of emissions-free power for FPL customers, which is enough energy to serve roughly 1,100 homes. The second is a one-megawatt solar power facility that will provide renewable energy directly to Kennedy. The FPL facilities at NASA will help provide Florida residents and America's space program with new sources of clean energy that will cut reliance on fossil fuels and improve the environment by reducing greenhouse gas emissions. The one megawatt facility also will help NASA meet its goal for use of power generated from renewable energy. Photo credit: NASA/Kim Shiflett
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2009-05-27
CAPE CANAVERAL, Fla. – Center Director of NASA's Kennedy Space Center in Florida, Bob Cabana addresses guests at the groundbreaking ceremony for the joint NASA and Florida Power & Light, or FPL, solar power project at Kennedy. Others on the stage are (from left) Ed Smeloff with SunPower Corporation, Florida Rep. Suzanne Kosmas, Sen. Bill Nelson, Armando Olivera, president and CEO of FPL, Florida Rep. Bill Posey, Eric Draper, deputy director of Audubon of Florida, and Pam Rauch, vice president of External Affairs for FPL. FPL, Florida's largest electric utility, will build and maintain two solar photovoltaic power generation systems at Kennedy. One will produce an estimated 10 megawatts of emissions-free power for FPL customers, which is enough energy to serve roughly 1,100 homes. The second is a one-megawatt solar power facility that will provide renewable energy directly to Kennedy. The FPL facilities at NASA will help provide Florida residents and America's space program with new sources of clean energy that will cut reliance on fossil fuels and improve the environment by reducing greenhouse gas emissions. The one megawatt facility also will help NASA meet its goal for use of power generated from renewable energy. Photo credit: NASA/Kim Shiflett
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Kairis, Or; Kosmas, C; Karavitis, Ch; Ritsema, C; Salvati, L; Acikalin, S; Alcalá, M; Alfama, P; Atlhopheng, J; Barrera, J; Belgacem, A; Solé-Benet, A; Brito, J; Chaker, M; Chanda, R; Coelho, C; Darkoh, M; Diamantis, I; Ermolaeva, O; Fassouli, V; Fei, W; Feng, J; Fernandez, F; Ferreira, A; Gokceoglu, C; Gonzalez, D; Gungor, H; Hessel, R; Juying, J; Khatteli, H; Khitrov, N; Kounalaki, A; Laouina, A; Lollino, P; Lopes, M; Magole, L; Medina, L; Mendoza, M; Morais, P; Mulale, K; Ocakoglu, F; Ouessar, M; Ovalle, C; Perez, C; Perkins, J; Pliakas, F; Polemio, M; Pozo, A; Prat, C; Qinke, Y; Ramos, A; Ramos, J; Riquelme, J; Romanenkov, V; Rui, L; Santaloia, F; Sebego, R; Sghaier, M; Silva, N; Sizemskaya, M; Soares, J; Sonmez, H; Taamallah, H; Tezcan, L; Torri, D; Ungaro, F; Valente, S; de Vente, J; Zagal, E; Zeiliguer, A; Zhonging, W; Ziogas, A
2014-11-01
Indicator-based approaches are often used to monitor land degradation and desertification from the global to the very local scale. However, there is still little agreement on which indicators may best reflect both status and trends of these phenomena. In this study, various processes of land degradation and desertification have been analyzed in 17 study sites around the world using a wide set of biophysical and socioeconomic indicators. The database described earlier in this issue by Kosmas and others (Environ Manage, 2013) for defining desertification risk was further analyzed to define the most important indicators related to the following degradation processes: water erosion in various land uses, tillage erosion, soil salinization, water stress, forest fires, and overgrazing. A correlation analysis was applied to the selected indicators in order to identify the most important variables contributing to each land degradation process. The analysis indicates that the most important indicators are: (i) rain seasonality affecting water erosion, water stress, and forest fires, (ii) slope gradient affecting water erosion, tillage erosion and water stress, and (iii) water scarcity soil salinization, water stress, and forest fires. Implementation of existing regulations or policies concerned with resources development and environmental sustainability was identified as the most important indicator of land protection.
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Recent results obtained on the APEX 12 m antenna with the ArTeMiS prototype camera
NASA Astrophysics Data System (ADS)
Talvard, M.; André, P.; Rodriguez, L.; Le-Pennec, Y.; De Breuck, C.; Revéret, V.; Agnèse, P.; Boulade, O.; Doumayrou, E.; Dubreuil, D.; Ercolani, E.; Gallais, P.; Horeau, B.; Lagage, PO; Leriche, B.; Lortholary, M.; Martignac, J.; Minier, V.; Pantin, E.; Rabanus, D.; Relland, J.; Willmann, G.
2008-07-01
ArTeMiS is a camera designed to operate on large ground based submillimetric telescopes in the 3 atmospheric windows 200, 350 and 450 µm. The focal plane of this camera will be equipped with 5760 bolometric pixels cooled down at 300 mK with an autonomous cryogenic system. The pixels have been manufactured, based on the same technology processes as used for the Herschel-PACS space photometer. We review in this paper the present status and the future plans of this project. A prototype camera, named P-ArTeMiS, has been developed and successfully tested on the KOSMA telescope in 2006 at Gornergrat 3100m, Switzerland. Preliminary results were presented at the previous SPIE conference in Orlando (Talvard et al, 2006). Since then, the prototype camera has been proposed and successfully installed on APEX, a 12 m antenna operated by the Max Planck Institute für Radioastronomie, the European Southern Observatory and the Onsala Space Observatory on the Chajnantor site at 5100 m altitude in Chile. Two runs have been achieved in 2007, first in March and the latter in November. We present in the second part of this paper the first processed images obtained on star forming regions and on circumstellar and debris disks. Calculated sensitivities are compared with expectations. These illustrate the improvements achieved on P-ArTeMiS during the 3 experimental campaigns.
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SOFIA/GREAT Discovery of Terahertz Water Masers
NASA Astrophysics Data System (ADS)
Neufeld, David A.; Melnick, Gary J.; Kaufman, Michael J.; Wiesemeyer, Helmut; Güsten, Rolf; Kraus, Alex; Menten, Karl M.; Ricken, Oliver; Faure, Alexandre
2017-07-01
We report the discovery of water maser emission at frequencies above 1 THz. Using the GREAT instrument on SOFIA, we have detected emission in the 1.296411 THz {8}27-{7}34 transition of water toward three oxygen-rich evolved stars: W Hya, U Her, and VY CMa. An upper limit on the 1.296 THz line flux was obtained toward R Aql. Near-simultaneous observations of the 22.23508 GHz {6}16-{5}23 water maser transition were carried out toward all four sources using the Effelsberg 100 m telescope. The measured line fluxes imply 22 GHz/1.296 THz photon luminosity ratios of 0.012, 0.12, and 0.83, respectively, for W Hya, U Her, and VY CMa, values that confirm the 22 GHz maser transition to be unsaturated in W Hya and U Her. We also detected the 1.884888 THz {8}45-{7}52 transition toward W Hya and VY CMa, and the 1.278266 THz {7}43-{6}52 transition toward VY CMa. Like the 22 GHz maser transition, all three of the THz emission lines detected here originate from the ortho-H2O spin isomer. Based upon a model for the circumstellar envelope of W Hya, we estimate that stimulated emission is responsible for ˜85% of the observed 1.296 THz line emission, and thus that this transition may be properly described as a terahertz-frequency maser. In the case of the 1.885 THz transition, by contrast, our W Hya model indicates that the observed emission is dominated by spontaneous radiative decay, even though a population inversion exists. GREAT is a development by the MPI für Radioastronomie and the KOSMA/Universität zu Köln, in cooperation with the MPI für Sonnensystemforschung and the DLR Institut für Planetenforschung.
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OT1_nschneid_1: Pillars of creation: physical origin and connection to star formation
NASA Astrophysics Data System (ADS)
Schneider, N.
2010-07-01
Herschel SPIRE/PACS photometry observations performed within the HOBYS (Herschel imaging survey of OB Young Stellar objects) key program have revealed a wealth of interesting structures in high-mass star forming regions. The most spectacular of those are 'pillars' and 'globules'. These features -- partly known from Hubble Space telescope or Spitzer images -- are formed due to photoevaporation at the interface between a molecular cloud and an HII region, and are thus intimately linked to high-mass star formation. The process of how these pillars are created, and under which conditions low- or high-mass stars form within them, are not yet clear. Classical approaches (e.g. Rayleigh-Taylor) can not explain pillar formation, so we have embarked upon a dedicated project to fully simulate pillars and globules using the (magneto)-hydrodynamic code HERACLES that comprises gravity and ionization. The model is intended to be coupled with a radiative transfer photon dominated region code (KOSMA-tau). We propose here to make use of the Herschel spectroscopy capacities to map/make single pointings, in a number of atomic and molecular lines, of selected pillars and globules in three different regions (Rosette, Cygnus, M16), spanning a large range in UV intensity and density. We intend to observe the important cooling lines of [CII] at 158 micron and [OI] at 63 and 145 micron with PACS, the [CI] finestructure lines at 370 and 609 micron and the mid-to high-J CO and HCO+ ladder with the SPIRE FTS. Spectrally resolved [CII] mapping with HIFI is also required to derive the velocity information. These observations will be compared to the large existing complementary data set for each source, to study the physics of pillars and will additionally serve as input for the models, to ultimately explain pillar formation and star formation within them.
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PREFACE: IC-MSQUARE 2012: International Conference on Mathematical Modelling in Physical Sciences
NASA Astrophysics Data System (ADS)
Kosmas, Theocharis; Vagenas, Elias; Vlachos, Dimitrios
2013-02-01
The first International Conference on Mathematical Modelling in Physical Sciences (IC-MSQUARE) took place in Budapest, Hungary, from Monday 3 to Friday 7 September 2012. The conference was attended by more than 130 participants, and hosted about 290 oral, poster and virtual papers by more than 460 pre-registered authors. The first IC-MSQUARE consisted of different and diverging workshops and thus covered various research fields in which mathematical modelling is used, such as theoretical/mathematical physics, neutrino physics, non-integrable systems, dynamical systems, computational nanoscience, biological physics, computational biomechanics, complex networks, stochastic modelling, fractional statistics, DNA dynamics, and macroeconomics. The scientific program was rather heavy since after the Keynote and Invited Talks in the morning, two parallel sessions ran every day. However, according to all attendees, the program was excellent with a high level of talks and the scientific environment was fruitful; thus all attendees had a creative time. The mounting question is whether this occurred accidentally, or whether IC-MSQUARE is a necessity in the field of physical and mathematical modelling. For all of us working in the field, the existing and established conferences in this particular field suffer from two distinguished and recognized drawbacks: the first is the increasing orientation, while the second refers to the extreme specialization of the meetings. Therefore, a conference which aims to promote the knowledge and development of high-quality research in mathematical fields concerned with applications of other scientific fields as well as modern technological trends in physics, chemistry, biology, medicine, economics, sociology, environmental sciences etc., appears to be a necessity. This is the key role that IC-MSQUARE will play. We would like to thank the Keynote Speaker and the Invited Speakers for their significant contributions to IC-MSQUARE. We would also like to thank the members of the International Scientific Committee and the members of the Organizing Committee. Conference Chairmen Theocharis Kosmas Department of Physics, University of Ioannina Elias Vagenas RCAAM, Academy of Athens Dimitrios Vlachos Department of Computer Science and Technology, University of Peloponnese The PDF also contains a list of members of the International Scientific Committes and details of the Keynote and Invited Speakers.
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Relation of runoff and soil erosion to weather types in the Mediterranean basin
NASA Astrophysics Data System (ADS)
Nadal-Romero, Estela; Peña-Angulo, Dhais
2017-04-01
Nadal-Romero, E. (1), Peña-Angulo, D. (1), Albaladejo, J. (2), Andreu, V. (3), Bahri, H. (4), Bagarello, V. (5), Batalla, R., (6), Bienes, R. (7), Campo, J. (3), Campo-Bescós, M.A. (8), Canatario, A. (9), Cantón, Y. (10), Casali, J. (8), Castillo, V. (2), Cid, P. (11), Cortesi, N. (12), Desir, G. (13), Díaz, E. (2), Ferreira, C. (14), Ferro, V. (5), Giménez, R. (8), Gimeno, E. (3), Gómez, J.A. (15), Gómez-Gutiérrez, A. (16), González-Hidalgo, J.C. (1), Klotz, S. (17) Kosmas, C. (18), Lana-Renault, N. (19), Lasanta, T. (20), Lázaro, R., (21), Le Bissonnais, Y. (22), Le Bouteiller, C. (17), Licciardello, F. (23), López-Tarazón, J.A. (24), Lucía, A. (25), Marín, C. (13), Marqués, M.J., (26) Martínez-Fernández, J. (27), Martínez-Mena, M. (2), Martínez-Murillo, J.F. (28), Mateos, L. (15), Novara, A. (5), Pachecho, E. (29), Raclot, D. (22), Rodríguez-Blanco, M.L. (30), Romero-Díaz, A. (31), Rubio, J.L. (3), Ruiz-Sinoga, J.D. (28), Schnabel, S. (16), Simonneaux, V. (32), Solé-Benet, A. (21), Taguas, E.V. (33), Taboada-Castro, M.M. (30), Taboada-Casto, M.T. (30), Todisco, F. (34), Úbeda, X. (29), Varouchakis, E. A. (35), Zabaleta, A. (36), Zorn, M. (37) (1) Departamento de Geografía, Instituto Universitario de Ciencias Ambientales (IUCA), Universidad de Zaragoza, Zaragoza, Spain (2) Soil and water conservation research group, CEBAS-CSIC, Murcia, Spain (3) Degradación y conservación de suelos, Centro de Investigación sobre Desertificación (CIDE), Valencia, Spain (4) INRGREF, Tunis, Tunisia (5) Department of Scienze Agrarie e Forestali, University of Palermo, viale delle scienze, Palermo, Italy (6) Department de Medi Ambient, Universitat de Lleida, Lleida, Spain (7) Departamento Investigación Aplicada y Extensión Agraria. Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Madrid, Spain (8) Escuela Técnica Superior de Ingeniería Agrónoma, Universidad Pública de Navarra, Pamplona, Spain (9) Polytechnic Institute of Catelo Branco, School of Agriculture (ESACB), Portugal (10) Departamento de Agronomía, Universidad de Almería, Almería, Spain (11) Center for Research and Advanced Studies of the Nactional Polytechnic Institute, Mexico City, DF, Mexico (12) Centro Nacional de Supercomputacion, Department of Earth Sciences, Barcelona, Spain (13) Departamento de Ciencias de la Tierra, Universidad de Zaragoza, Zaragoza, Spain (14) Centro de Estudos de Recursos Naturais, Ambiente e Sociedade (CERNAS), Coimbra Agrarian Technical School, Polytechnic Institute of Coimbra, Coimbra, Portugal (15) Instituto de Agricultura Sostenible—CSIC, Córdoba, Spain (16) Grupo de Investigación GeoAmbiental (GIGA), Área de Geografía Física, Facultad de Filosofía y Letras. Universidad de Extremadura, Cáceres, Spain (17) Department of Waters, National Research Institute of Science and Technology for Environment and Agriculture, France (18) Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, Athens, Greece (19) Area of Physical Geography, Luis Vives Building, Luis de Ulloa Street, University of La Rioja, 26006 Logroño, Spain (20) Instituto Pirenaico de Ecología, IPE-CSIC, Zaragoza, Spain (21) Estación Experimental de Zonas Áridas, EEZA-CSIC, Almería, Spain (22) IRD, LISAH, Montpellier, France (23) Department of Agri-Food and Environmental Systems Management, University of Catania, Catania, Italy (24) Institute of Earth and Environmental Science, University of Potsdam, Potsdam, Germany (25) Center for Applied Geosciences. Faculty of Science, Eberhard Karls Universität Tübingen, Germany (26) Departamento de Geología y Geoquímica, Universidad Autónoma Madrid, Madrid, Spain (27) Departamento de Geografía, Universidad de Salamanca, Salamanca, Spain (28) Departamento de Geografía, Grupo de Investigación Geografía Física y Territorio—RNM279, Andalucía Tech, Universidad de Málaga, Málaga, Spain (29) Grup de Recerca Ambiental Mediterrània, Departamento de Geografia Física i AGR, Universitat de Barcelona, Spain (30) Facultad de Ciencias and Centro de Investigaciones Científicas Avanzadas (CICA), University of A Coruña, Campus de A Coruña, Spain (31) Departamento de Geografía, Universidad de Murcia, Murcia, Spain (32) French National Research Institut for Sustainable Development (IRD), CESBIO Laboratory, Toulouse, France. (33) Escuela Técnica Superior de Ingeniería Agronómica e I. de Montes, Departamento de Ingeniería Rural, Universidad de Córdoba, Córdoba, Spain (34) Departament of Environmental and Agricultural Sciences, Università degli Studi di Perugia, Perugia, Italy (35) Technical University of Crete, School of Environmental Engineering, Chania, Greece (36) Departamento de Geodinámica, Universidad del País Vasco UPV/EHU, Leioa, Spain (37) Geographical Institute, Research Centre of the Slovenian Academy of Sciences and Arts, Ljubljana, Slovenia Erosion processes and land degradation are recognized as one of the most significant environmental problems worldwide. In the Mediterranean region, intense erosion processes occur as a consequence of complex interactions between environmental conditions (e.g. climate, lithology) and human-related factors (e.g. history of human activity, land use changes) (García-Ruiz et al., 2013). Precipitation has been recognized as one of the main factors driving soil erosion. In climatology, one of the most common approaches in analyzing spatial and temporal precipitation variability is the circulation of weather types (WTs), which categorize the continuum of atmospheric circulation into a small number of classes or types. Flood generation and soil erosion are associated with specific weather conditions. Previous research in the Iberian Peninsula has analyzed the relationship between precipitation and specific WTs, demonstrating that specific WTs are the main drivers of precipitation and soil erosion in the different areas (Cortesi et al., 2014; Nadal-Romero et al., 2015). In this study, we present a preliminary analysis of WTs and runoff and soil erosion data from 50 study areas in the Mediterranean basin including different land uses. To do so,we have collected and jointed different research groups cross the Mediterranean Basin, and combined different databases (plots and small representative catchments) with the WT classification calculated using the NCEP/NCAR 40-Year Reanalysis Project. This pioneer research will be a valuable tool in understanding the relationships between weather types, precipitation and soil erosion dynamics. Acknowledgments Estela Nadal-Romero was the beneficiary of a "Ramón y Cajal" postdoctoral contract (Spanish Ministry of Economy and Competitiveness). José Andrés López-Tarazón is in receipt of a Marie Curie Intra-European Fellowship (Project ''Floodhazards'', PIEF-GA-2013-622468, Seventh EU Framework Programme). References Cortesi, N., González-Hidalgo, J.C., Trigo, R.M., Ramos, A.M., 2014. Weather types and spatial variability of precipitation in the Iberian Peninsula. International Journal of Climatology 34(8), 2661-2677. García-Ruiz, J.M., Nadal-Romero, E., Lana-Renault, N., Beguería, S., 2013. Erosion in Mediterranean landscapes: Changes and future challenges. Geomorphology 198, 20-36. Nadal-Romero, E., González-Hidalgo, J.C., Cortesi, N., Desir, G., Gómez, J.A., et al., 2015. Relationship of runoff, erosion and sediment yield to weather types in the Iberian Peninsula. Geomorphology 228, 372-381.
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NASA Astrophysics Data System (ADS)
Dorn, O.; Lesselier, D.
2010-07-01
Inverse problems in electromagnetics have a long history and have stimulated exciting research over many decades. New applications and solution methods are still emerging, providing a rich source of challenging topics for further investigation. The purpose of this special issue is to combine descriptions of several such developments that are expected to have the potential to fundamentally fuel new research, and to provide an overview of novel methods and applications for electromagnetic inverse problems. There have been several special sections published in Inverse Problems over the last decade addressing fully, or partly, electromagnetic inverse problems. Examples are: Electromagnetic imaging and inversion of the Earth's subsurface (Guest Editors: D Lesselier and T Habashy) October 2000 Testing inversion algorithms against experimental data (Guest Editors: K Belkebir and M Saillard) December 2001 Electromagnetic and ultrasonic nondestructive evaluation (Guest Editors: D Lesselier and J Bowler) December 2002 Electromagnetic characterization of buried obstacles (Guest Editors: D Lesselier and W C Chew) December 2004 Testing inversion algorithms against experimental data: inhomogeneous targets (Guest Editors: K Belkebir and M Saillard) December 2005 Testing inversion algorithms against experimental data: 3D targets (Guest Editors: A Litman and L Crocco) February 2009 In a certain sense, the current issue can be understood as a continuation of this series of special sections on electromagnetic inverse problems. On the other hand, its focus is intended to be more general than previous ones. Instead of trying to cover a well-defined, somewhat specialized research topic as completely as possible, this issue aims to show the broad range of techniques and applications that are relevant to electromagnetic imaging nowadays, which may serve as a source of inspiration and encouragement for all those entering this active and rapidly developing research area. Also, the construction of this special issue is likely to have been different from preceding ones. In addition to the invitations sent to specific research groups involved in electromagnetic inverse problems, the Guest Editors also solicited recommendations, from a large number of experts, of potential authors who were thereupon encouraged to contribute. Moreover, an open call for contributions was published on the homepage of Inverse Problems in order to attract as wide a scope of contributions as possible. This special issue's attempt at generality might also define its limitations: by no means could this collection of papers be exhaustive or complete, and as Guest Editors we are well aware that many exciting topics and potential contributions will be missing. This, however, also determines its very special flavor: besides addressing electromagnetic inverse problems in a broad sense, there were only a few restrictions on the contributions considered for this section. One requirement was plausible evidence of either novelty or the emergent nature of the technique or application described, judged mainly by the referees, and in some cases by the Guest Editors. The technical quality of the contributions always remained a stringent condition of acceptance, final adjudication (possibly questionable either way, not always positive) being made in most cases once a thorough revision process had been carried out. Therefore, we hope that the final result presented here constitutes an interesting collection of novel ideas and applications, properly refereed and edited, which will find its own readership and which can stimulate significant new research in the topics represented. Overall, as Guest Editors, we feel quite fortunate to have obtained such a strong response to the call for this issue and to have a really wide-ranging collection of high-quality contributions which, indeed, can be read from the first to the last page with sustained enthusiasm. A large number of applications and techniques is represented, overall via 16 contributions with 45 authors in total. This shows, in our opinion, that electromagnetic imaging and inversion remain amongst the most challenging and active research areas in applied inverse problems today. Below, we give a brief overview of the contributions included in this issue, ordered alphabetically by the surname of the leading author. 1. The complexity of handling potential randomness of the source in an inverse scattering problem is not minor, and the literature is far from being replete in this configuration. The contribution by G Bao, S N Chow, P Li and H Zhou, `Numerical solution of an inverse medium scattering problem with a stochastic source', exemplifies how to hybridize Wiener chaos expansion with a recursive linearization method in order to solve the stochastic problem as a set of decoupled deterministic ones. 2. In cases where the forward problem is expensive to evaluate, database methods might become a reliable method of choice, while enabling one to deliver more information on the inversion itself. The contribution by S Bilicz, M Lambert and Sz Gyimóthy, `Kriging-based generation of optimal databases as forward and inverse surrogate models', describes such a technique which uses kriging for constructing an efficient database with the goal of achieving an equidistant distribution of points in the measurement space. 3. Anisotropy remains a considerable challenge in electromagnetic imaging, which is tackled in the contribution by F Cakoni, D Colton, P Monk and J Sun, `The inverse electromagnetic scattering problem for anisotropic media', via the fact that transmission eigenvalues can be retrieved from a far-field scattering pattern, yielding, in particular, lower and upper bounds of the index of refraction of the unknown (dielectric anisotropic) scatterer. 4. So-called subspace optimization methods (SOM) have attracted a lot of interest recently in many fields. The contribution by X Chen, `Subspace-based optimization method for inverse scattering problems with an inhomogeneous background medium', illustrates how to address a realistic situation in which the medium containing the unknown obstacles is not homogeneous, via blending a properly developed SOM with a finite-element approach to the required Green's functions. 5. H Egger, M Hanke, C Schneider, J Schöberl and S Zaglmayr, in their contribution `Adjoint-based sampling methods for electromagnetic scattering', show how to efficiently develop sampling methods without explicit knowledge of the dyadic Green's function once an adjoint problem has been solved at much lower computational cost. This is demonstrated by examples in demanding propagative and diffusive situations. 6. Passive sensor arrays can be employed to image reflectors from ambient noise via proper migration of cross-correlation matrices into their embedding medium. This is investigated, and resolution, in particular, is considered in detail, as a function of the characteristics of the sensor array and those of the noise, in the contribution by J Garnier and G Papanicolaou, `Resolution analysis for imaging with noise'. 7. A direct reconstruction technique based on the conformal mapping theorem is proposed and investigated in depth in the contribution by H Haddar and R Kress, `Conformal mapping and impedance tomography'. This paper expands on previous work, with inclusions in homogeneous media, convergence results, and numerical illustrations. 8. The contribution by T Hohage and S Langer, `Acceleration techniques for regularized Newton methods applied to electromagnetic inverse medium scattering problems', focuses on a spectral preconditioner intended to accelerate regularized Newton methods as employed for the retrieval of a local inhomogeneity in a three-dimensional vector electromagnetic case, while also illustrating the implementation of a Lepskiĭ-type stopping rule outsmarting a traditional discrepancy principle. 9. Geophysical applications are a rich source of practically relevant inverse problems. The contribution by M Li, A Abubakar and T Habashy, `Application of a two-and-a-half dimensional model-based algorithm to crosswell electromagnetic data inversion', deals with a model-based inversion technique for electromagnetic imaging which addresses novel challenges such as multi-physics inversion, and incorporation of prior knowledge, such as in hydrocarbon recovery. 10. Non-stationary inverse problems, considered as a special class of Bayesian inverse problems, are framed via an orthogonal decomposition representation in the contribution by A Lipponen, A Seppänen and J P Kaipio, `Reduced order estimation of nonstationary flows with electrical impedance tomography'. The goal is to simultaneously estimate, from electrical impedance tomography data, certain characteristics of the Navier--Stokes fluid flow model together with time-varying concentration distribution. 11. Non-iterative imaging methods of thin, penetrable cracks, based on asymptotic expansion of the scattering amplitude and analysis of the multi-static response matrix, are discussed in the contribution by W-K Park, `On the imaging of thin dielectric inclusions buried within a half-space', completing, for a shallow burial case at multiple frequencies, the direct imaging of small obstacles (here, along their transverse dimension), MUSIC and non-MUSIC type indicator functions being used for that purpose. 12. The contribution by R Potthast, `A study on orthogonality sampling' envisages quick localization and shaping of obstacles from (portions of) far-field scattering patterns collected at one or more time-harmonic frequencies, via the simple calculation (and summation) of scalar products between those patterns and a test function. This is numerically exemplified for Neumann/Dirichlet boundary conditions and homogeneous/heterogeneous embedding media. 13. The contribution by J D Shea, P Kosmas, B D Van Veen and S C Hagness, `Contrast-enhanced microwave imaging of breast tumors: a computational study using 3D realistic numerical phantoms', aims at microwave medical imaging, namely the early detection of breast cancer. The use of contrast enhancing agents is discussed in detail and a number of reconstructions in three-dimensional geometry of realistic numerical breast phantoms are presented. 14. The contribution by D A Subbarayappa and V Isakov, `Increasing stability of the continuation for the Maxwell system', discusses enhanced log-type stability results for continuation of solutions of the time-harmonic Maxwell system, adding a fresh chapter to the interesting story of the study of the Cauchy problem for PDE. 15. In their contribution, `Recent developments of a monotonicity imaging method for magnetic induction tomography in the small skin-depth regime', A Tamburrino, S Ventre and G Rubinacci extend the recently developed monotonicity method toward the application of magnetic induction tomography in order to map surface-breaking defects affecting a damaged metal component. 16. The contribution by F Viani, P Rocca, M Benedetti, G Oliveri and A Massa, `Electromagnetic passive localization and tracking of moving targets in a WSN-infrastructured environment', contributes to what could still be seen as a niche problem, yet both useful in terms of applications, e.g., security, and challenging in terms of methodologies and experiments, in particular, in view of the complexity of environments in which this endeavor is to take place and the variability of the wireless sensor networks employed. To conclude, we would like to thank the able and tireless work of Kate Watt and Zoë Crossman, as past and present Publishers of the Journal, on what was definitely a long and exciting journey (sometimes a little discouraging when reports were not arriving, or authors were late, or Guest Editors overwhelmed) that started from a thorough discussion at the `Manchester workshop on electromagnetic inverse problems' held mid-June 2009, between Kate Watt and the Guest Editors. We gratefully acknowledge the fact that W W Symes gave us his full backing to carry out this special issue and that A K Louis completed it successfully. Last, but not least, the staff of Inverse Problems should be thanked, since they work together to make it a premier journal.