Relevant bibliographies by topics / Step migration

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Step migration'

Author: Grafiati
Published: 25 January 2025

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Journal articles on the topic "Step migration"

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Stoffa, P. L., J. T. Fokkema, R. M. de Luna Freire, and W. P. Kessinger. "Split‐step Fourier migration." GEOPHYSICS 55, no. 4 (April 1990): 410–21. http://dx.doi.org/10.1190/1.1442850.

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The split‐step Fourier method is developed and applied to migrating stacked seismic data in two and three dimensions. This migration method, which is implemented in both the frequency‐wavenumber and frequency‐space domains, takes into account laterally varying velocity by defining a reference slowness (reciprocal of velocity) as the mean slowness in the migration interval and a perturbation term that is spatially varying. The mean slowness defines a reference vertical wavenumber which is used in the frequency‐wavenumber domain to downward continue the data across a depth interval as in constant‐velocity phase‐shift migration. The perturbation term is used to define a “source” contribution that is taken into account by the application of a second phase shift in the frequency‐space domain. Since the method does not include the effects of second and higher order spatial derivatives of the slowness field, the method theoretically is accurate only when there are no rapid lateral slowness variations combined with steep angles of propagation. However, synthetic and real examples indicate that good results are obtained for realistic geologic structures.
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Larner, Ken, and Craig Beasley. "Cascaded migrations: Improving the accuracy of finite‐difference migration." GEOPHYSICS 52, no. 5 (May 1987): 618–43. http://dx.doi.org/10.1190/1.1442331.

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The accuracy of time migrations done with finite‐difference schemes deteriorates with increasing reflector dip. Some properties of migration in general, and of finite‐difference approaches in particular, suggest a way of improving the accuracy of finite‐difference schemes for migrating steep dips. First, although data will be undermigrated when too low a velocity is used in migration, a correctly migrated result can be obtained by migrating again, this time with the previously undermigrated result as input. In fact, a sequence of undermigrations will yield the correct result as long as the sum of the squares of the migration velocities used in the different migration stages equals the square of the correct migration velocity. A second property is that the apparent spatial dip of a reflector perceived by the migration process is a function of not only the time dip of the unmigrated reflection, but also the velocity used in the migration. In a sequence of low‐velocity migrations, the apparent spatial dip perceived at each migration stage can be considerably less than the true dip. Thus, because finite‐difference migration is accurate for small spatial dips, the cascaded migrations yield a more accurate result than that of single‐stage migration. Also, because each migration stage is done with low velocity, the depth step can be large; hence, the computational effort need not be. The accuracy of the method is not compromised (in fact, it improves) in media in which velocity increases with depth. Moreover, the cascaded approach suffers no more than other methods of time migration where velocity varies mildly in the lateral direction. In applications of the method to stacked data from the Gulf of Mexico, reflections from near‐vertical flanks of salt domes were migrated with accuracy comparable to that achieved by frequency‐wavenumber domain migration.
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Ashraf, Syed Ziauarrahman. "Data Migration Strategies: A Step-by-Step Guide." Journal of Artificial Intelligence, Machine Learning and Data Science 1, no. 1 (January 20, 2024): 1593–97. https://doi.org/10.51219/jaimld/syed-ziaurrahman-ashraf/357.

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Cooke, Dennis, Andrej Bóna, and Benn Hansen. "Simultaneous time imaging, velocity estimation, and multiple suppression using local event slopes." GEOPHYSICS 74, no. 6 (November 2009): WCA65—WCA73. http://dx.doi.org/10.1190/1.3242751.

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Starting with the double-square-root equation we derive expressions for a velocity-independent prestack time migration and for the associated migration velocity. We then use that velocity to identify multiples and suppress them as part of the imaging step. To describe our algorithm, workflow, and products, we use the terms velocity-independent and oriented. While velocity-independent imaging does not require an input migration velocity, it does require input [Formula: see text]-values (also called local event slopes) measured in both the shot and receiver domains. There are many possible methods of calculating these required input [Formula: see text]-values, perhaps the simplest is to compute the ratio of instantaneous spatial frequency to instantaneous temporal frequency. Using a synthetic data set rich in multiples, we test the oriented algorithm and generate migrated prestack gathers, the oriented migration velocity field, and stacked migrations. We use oriented migration velocities for prestack multiple suppression. Without this multiple suppression step, the velocity-independent migration is inferior to a conventional Kirchhoff migration because the oriented migration will flatten primaries and multiples alike in the common image domain. With this multiple suppression step, the velocity-independent are very similar to a Kirchhoff migration generated using the known migration velocity of this test data set.
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Badov, A. D. "New Step in Migration Study." Izvestiya Rossiiskoi Akademii Nauk. Seriya Geograficheskaya., no. 3 (July 21, 2015): 118. http://dx.doi.org/10.15356/0373-2444-2012-3-118-119.

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Lee, Hong‐Yuan, and Shie‐Tsung Hwang. "Migration of Backward‐Facing Step." Journal of Hydraulic Engineering 120, no. 6 (June 1994): 693–705. http://dx.doi.org/10.1061/(asce)0733-9429(1994)120:6(693).

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Arntsen, Børge, Constantin Gerea, and Tage Røsten. "Imaging salt bodies using explicit migration operators offshore Norway." GEOPHYSICS 74, no. 2 (March 2009): S25—S32. http://dx.doi.org/10.1190/1.3063660.

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We have tested the performance of 3D shot-profile depth migration using explicit migration operators on a real 3D marine data set. The data were acquired offshore Norway in an area with a complex subsurface containing large salt bodies. We compared shot-profile migration using explicit migration operators with conventional Kirchhoff migration, split-step Fourier migration, and common-azimuth by generalized screen propagator (GSP) migration in terms of quality and computational cost. Image quality produced by the explicit migration operator approach is slightly better than with split-step Fourier migration and clearly better than in common-azimuth by GSP and Kirchhoff migrations. The main differences are fewer artifacts and better-suppressed noise within the salt bodies. Kirchhoff migration shows considerable artifacts (migration smiles) within and close to the salt bodies, which are not present in images produced by the other three wave-equation methods. Expressions for computational cost were developed for all four migration algorithms in terms of frequency content and acquisition parameters. For comparable frequency content, migration cost using explicit operators is four times the cost of the split-step Fourier method, up to 260 times the cost of common-azimuth by GSP migration, and 25 times the cost of Kirchhoff migration. Our results show that in terms of image quality, shot-profile migration using explicit migration operators is well suited for imaging in areas with complex geology and significant velocity changes. However, computational cost of the method is high and makes it less attractive in terms of efficiency.
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Popovici, Alexander Mihai. "Prestack migration by split‐step DSR." GEOPHYSICS 61, no. 5 (September 1996): 1412–16. http://dx.doi.org/10.1190/1.1444065.

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The double‐square‐root (DSR) prestack migration equation, though defined for depth variable velocity, can be used to image media with strong velocity variations using a phase‐shift plus interpolation (PSPI) or split‐step correction. The split‐step method is based on applying a phase‐shift correction to the extrapolated wavefield—a correction that attempts to compensate for the lateral velocity variations. I show how to extend DSR prestack migration to lateral velocity media and exemplify the method by applying the new algorithm to the Marmousi data set. The split‐step DSR migration is very fast and offers excellent imaging results.
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Wenzel, F. "Frequency‐wavenumber migration in laterally heterogeneous media." GEOPHYSICS 56, no. 10 (October 1991): 1671–73. http://dx.doi.org/10.1190/1.1442977.

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In a recent paper, Stoffa et al. (1990) presented a split‐step Fourier migration method. It takes laterally varying migration velocities into account by splitting the reference slowness into an average slowness, constant within the migration interval, and a perturbation term which accounts for the lateral variations. The method works accurately only if the lateral slowness variations are smooth and angles of propagation are near‐vertical. The restriction to steep propagation angles stems from the fact that the wavefield is accurately propagated with respect to the reference slowness but a five‐degree approximation is used to accommodate the lateral variations. This note presents a theory that avoids the five‐degree assumption and thus generalizes the split‐step algorithm.
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Rickman, J. M., S. R. Phillpot, D. Wolf, D. L. Woodraska, and S. Yip. "On the mechanism of grain-boundary migration in metals: A molecular dynamics study." Journal of Materials Research 6, no. 11 (November 1991): 2291–304. http://dx.doi.org/10.1557/jmr.1991.2291.

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The migration of a (100) θ = 43.6°(Σ29) twist grain boundary is observed during the course of a molecular-dynamics simulation. The atomic-level details of the migration are investigated by determining the time dependence of the planar structure factor, a function of the planar interparticle bond angles, and the location of the center of a mass of planes near the grain boundary. It is found that a migration step consists of local bond rearrangements which, when the simulation cell is made large enough, produce domain-like structures in the migrating plane. Although no overall sliding is observed during migration, a local sliding of the planes near the migrating grain boundary accompanies the migration process. It is suggested that a three-dimensional cloud of thermally produced Frenkel-like point defects near the boundary accompanies, and facilitates, its migration.
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Dissertations / Theses on the topic "Step migration"

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Ng, Colin Uber. "STEP-enabled Force Measurement Platform of Single Migratory Cells." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/25329.

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Spinneret based Tunable Engineered Parameters (STEP) Platform is a recently reported pseudo-dry spinning and non-electrospinning technique that allows for the deposition of aligned polymeric nano-fibers with control on fiber diameters and orientation in single and multiple layers (diameter: sub 100nm micron, length: mm-cm), deposition (parallelism 2.5 degrees) and spacing (microns)). A wide range of polymers such as PLGA, PLA, PS, and PU have been utilized for their unique material properties in scaffold design. In this thesis two unique bioscaffolds are demonstrated for the measurement of group cell migration for wound closure and single cell contractility force for the study of force modulation. The wound healing assay bridges the gap between confluent reservoirs of NIH3T3 fibroblasts through arrangement of a suspended array of fibers guiding group cell migration along the fiber axis. This platform demonstrates that topographical and geometrical features of suspended fibers play a very important role in wound closure. Spacing, alignment and orientation were optimized to shown an increased rate of closure. In the second complementary assay, we report a fused-fiber network of suspended fibers capable of measuring single cell forces. Results from our experiments demonstrate that force behavior is dependent on mechanical properties such as stiffness and geometry of fiber networks. We also demonstrate changes in spatial and temporal organization of focal adhesion zyxin in response to single cell migration on these networks.
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Tanis, Mehmet Celaleddin. "Prestack split-step fourier depth migration algorithms and parallel implementations on Cray T3E /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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Jacobs, Albert. "Transport bactérien en milieu poreux : expérimentations et modélisation : migration de bactéries issues de boues de STEP." Avignon, 2007. http://www.theses.fr/2007AVIG0610.

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L’étude du transport bactérien en milieux poreux est un enjeu important pour la protection des nappes phréatiques contre des contaminations microbiologiques. La pratique d’épandage des effluents des stations d’épuration est une source de bactéries pathogènes dont le déplacement dans le sol constitue un risque pour la santé publique. Le transport d’une bactérie dans un milieu poreux résulte d’une compétition entre processus de déplacement, d’adhésion et de blocage. Des expériences avec une large gamme de bactéries aux propriétés de surface différentes (composantes de la tension de surface et charges) ont été réalisées pour essayer de relier ces propriétés à leur rétention en milieu poreux. Les résultats montrent que les cinétiques de rétention sont corrélées aux interactions électrostatiques mais qu’il ne semble pas y avoir de corrélation entre l’énergie libre totale d’interaction et la quantité de bactéries retenues. L’observation in situ par microscopie confocale du déplacement de cellules d’Escherichia coli a mis en évidence le coinçage des cellules bactériennes par des rugosités de surface et les zones de contact entre grains d’un milieu poreux. Ces résultats confirment l’existence de possibilités de rétention en milieux poreux même en présence de conditions défavorables (énergie libre totale d’interaction positive). Des expériences de transport avec Escherichia coli conduites dans des milieux poreux se différentiant par leur porosité et physico-chimie ont été utilisées pour évaluer le poids respectif des phénomènes de transport et d’adhésion dans la migration de cellules et pour tester un modèle de transport. La restitution des courbes d’élution observées a requis la prise en compte de deux types de détachements des cellules retenues. Les cellules retenues par les interactions de faibles intensités (Lifshitz-van der Waals) peuvent se décrocher sous l’effet des forces hydrodynamiques ou par des répulsions électrostatiques dont la portée et l’intensité augmentent lorsque la force ionique de la solution diminue. Les cellules fortement retenues peuvent aussi se détacher mais à un rythme lent et donnent lieu à de longues traînées. Les résultats ont montré que dans les milieux homogènes le transport bactérien est principalement gouverné par les interactions électrostatiques, alors que dans des milieux présentant une porosité plus compliquée, le transport est moins dépendant des interactions électrostatiques, voire très peu influencé par celles-ci. L’étude du transport, dans un sable et dans un sol, d’une communauté bactérienne issue d’une boue de station d’épuration a montré les points suivants : i/ une forte réduction de la diversité microbienne et de la concentration bactérienne ; ii/ parmi les espèces transportées se trouvaient des coliformes fécaux ; iii/ les bactéries ayant traversé les colonnes sont chargées négativement. Ces résultats confirment le rôle important des interactions électrostatiques sur la migration de bactéries en milieux poreux
The study of bacterial transport in porous media is an important stake for the protection of ground water resources against microbial contaminations. Disposal of waste water plants effluents is an important source of pathogenic bacteria in the environment whose displacement in the ground may cause health concerns. The transport of a bacterium in a porous matrix is subjected to a competition between displacement, adhesion and blocking processes. Experiences with a broad range of bacteria with variable cellular surface properties revealed that the transport and adhesion behaviour is not identical for all the strains but depended on their respective hydrophobic and electrophoretic cell characteristics. Bacterial adhesion in porous media prevents their transport but is not an irreversible phenomenon. A model of bacterial transport in porous media able to reproduce correctly the experimental observations required to take into account two types of cell detachments: slow and fast. The cells retained by weak interactions (Lifshitz-van der Waals) can be detached by hydrodynamic forces or electrostatic repulsions whose range and intensity increase when the ionic force of a solution decreases. These results showed also that bacterial transport relied heavily on electrostatic interactions. Transport conditions are enhanced by higher electrostatic repulsions between cells and solid surface. In situ observations of Escherichia coli cells moving through pores highlighted the wedging of the bacterial cells by surface roughness and at zones of contact between porous media grains. In homogeneous mediums such as sand bacterial transport is mainly controlled by electrostatic interactions. However in heterogeneous mediums such as a soil hydrodynamics and porosity are more important. In particular for unsaturated soils where filtration of cells by small pores considerably reduces bacterial transport. The study of the fate in sand and soil media of bacterial communities from waste water plant sludge showed that faecal coliforms were among the species able to be transported. The results of this study made it possible to define safety rules related to waste water plants effluents spreading practices
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Al-Abdullah, Yahya. "Step Migration and Urban Integration : the Transnational Trajectory of the Dom Community from the Levant to the Northern Parisian Suburbs." Electronic Thesis or Diss., Paris, EHESS, 2024. http://www.theses.fr/2024EHES0097.

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Mon projet de recherche traite des déplacements forcés, la migration par étape et de l’insertion urbaine des Doms Syriens. Les Doms Syriens sont une minorité ethnique présente au Levant caractérisé par une forte marginalisation et précarité, un statut d'apatride, et un mode de vie semi-nomadique. Depuis 2012, une grande partie de cette communauté à quitter la Syrie pour s'installer d'abord en Turquie et au Liban, dans des camps de réfugiés. Une partie d'entre eux a par la suite immigré en France et en Belgique à partir de 2014. Leur installation récente en région parisienne les a contraintes à s’adapter à un nouvel environnement urbain et à trouver au jour le jour les moyens de subvenir aux besoins les plus urgents : se nourrir, se loger, se repérer dans l’espace afin de pouvoir s’y déplacer. Mon analyse de leur insertion urbaine se focalise dès lors sur trois thèmes : l’économie informelle, l’habitat et les interactions avec les autorités, avec comme fil conducteur la question de l'école. En effet, l'organisation du foyer est conditionnée par la scolarisation des enfants. Ainsi, une partie centrale de mes recherches se focalise sur la scolarisation des enfants doms comme vecteur d’intégration de la communauté, et ce pour plusieurs raisons. La première est que la quasi-totalité des enfants de la communauté ne bénéficient d’aucune expérience de scolarisation antérieure à leur déplacement, en raison de la stigmatisation de leur statut social en Syrie et du long voyage qu’ils ont dû accomplir pour parvenir en France. Certaines familles ont passé plus d’un an dans cinq pays différents dont le Liban, la Mauritanie, l’Algérie, le Maroc, l’enclave espagnole au Maroc et enfin la France. La seconde raison pour laquelle mes recherches se concentrent sur la scolarisation est l’impact décisif de l’éducation à la fois sur les enfants et sur leur famille. Elle met en jeu la relation des familles avec leur voisinage et les tactiques déployées au jour le jour à travers l’économie informelle, dans laquelle la communauté dom est impliquée
My research project deals with the forced displacement, step migration and urban integration of the Syrian Dom. The Syrian Dom are an ethnic minority present in the Levant, characterised by their strong marginalisation and precariousness, a stateless status, and a semi-nomadic lifestyle.Since 2012, a large part of this community has left Syria to settle in refugee camps in Turkey and Lebanon. Some of them subsequently immigrated to France and Belgium from 2014. Their recent settlement in the Paris region has forced them to adapt to a new urban environment, and to find the means to meet their most pressing needs on a day-to-day basis: food, housing and finding their way around the city. My analysis of their urban integration therefore focuses on three themes: the informal economy, housing and interactions with the authorities, with the question of school as a common thread. Indeed, the organization of the household is conditioned by the children's schooling.Thus, a central part of my research focuses on the schooling of Dom children as a vector of community integration, for several reasons. The first is that almost all the children in the community have no experience of schooling prior to their displacement, due to the stigmatization of their social status in Syria and the long journey they had to make to reach France. Some families have spent more than a year in five different countries, including Lebanon, Mauritania, Algeria, Morocco, the Spanish enclave in Morocco and finally France. The second reason is the decisive impact of education on both children and their families. It involves the relationship of families with their neighbourhoods and the tactics deployed on a day-to-day basis through the informal economy, in which the Dom community is involved
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Swartling, Malin. "Brexit: A step back in Britain’s fight against human trafficking? : A comparative content analysis of the Modern Slavery Act 2015 and the EU Directive 2011/36." Thesis, Uppsala universitet, Teologiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-444132.

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Human trafficking has become an international issue of significant importance; it is the largest and most profitable organised crime after drugs and arms trafficking. Particular concern has recently been raised due to the Brexit potential ramifications on Human trafficking. There is a risk that the EU directive 2011/36 will be repealed as a result of Brexit. Accordingly, it has been questioned whether the UK national efforts and legislation concerning human trafficking are comprehensive and sufficient enough without the strengthening support of the EU and especially the EU directive 2011/36. Thus, this thesis aimed to determine the impact Brexit will have on human trafficking in the UK by investigating if there will be "gaps" in the UK national legislation on human trafficking.  A comparative content analysis was conducted to analyse the UK national legislation on human trafficking, The Modern Slavery Act 2015 (MSA 2015). The Modern Slavery Act was compared with the EU directive 2011/36 to determine how the legislation differed. The method and analysis were conducted on both a latent and manifest level which means it both described the definitions and analysed how the definitions could be interpreted, hence how it affects reality. Based on what has commonly been argued the main reasons behind human trafficking in Europe, the content analysis focused on the definitions of human trafficking, prostitution and protection of migrant victims. Prostitution and migrations are frequently claimed to be the main reasons behind human trafficking in Europe.  Due to the risk of the EU directive 2011/36 being repealed, the result of the thesis exhibits the need for the UK to update their national legislation. The MSA 2015 needs to become coherent with international agreements and strengthen the protection of victims of human trafficking. Due to the gendered nature of human trafficking, this research addressed human trafficking from a feminist perspective by applying the "dominance theory" and the "sameness theory". The feminist theories helped analyse and investigate the issue of human trafficking and the potential ramifications of Brexit. Applying the ideas illustrated the patriarchal structures surrounding human trafficking and within the MSA 2015.
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Falk, Anna. "Stem cells : proliferation, differentiation, migration /." Stockholm, 2005. http://diss.kib.ki.se/2006/91-7140-497-X/.

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Erlandsson, Anna. "Neural Stem Cell Differentiation and Migration." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl.[distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3546.

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Zhao, Zhiqiang. "Electric field-directed cell migration and endothelialization." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until June 30, 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26544.

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Durand, Ellen Marie. "Regulation of hematopoietic stem cell migration and function." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11550.

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Hematopoietic stem cell transplantation (HSCT) is an effective treatment for blood disorders and autoimmune diseases. Following HSCT, these cells must successfully migrate to the marrow niche and replenish the blood system of the recipient. This process requires both non-cell and cell-autonomous regulation of hematopoietic stem and progenitor cells (HSPCs). A transgenic reporter line in zebrafish allowed the investigation of factors that regulate HSPC migration and function. To directly observe cells in their endogenous microenvironment, confocal live imaging was used to track runx1:GFP+ HSPCs as they arrive and lodge in the niche. A novel cellular interaction was observed that involves triggered remodeling of perivascular endothelial cells during niche formation. A chemical screen identified the TGF-beta pathway as a regulator of HSPC and niche interactions. Chemical manipulation of HSPCs was used to improve engraftment and repopulation capability following transplantation. Runx1:GFP fish treated with prostaglandin E2 (PGE2) during embryogenesis exhibit increased runx1+ cells in the AGM and CHT, consistent with previous in situ data. This increase in HSPCs is maintained into adulthood, even in the absence of prolonged PGE2 exposure. Kidney marrow from these treated fish can outcompete control marrow in transplantation assays. The ability of PGE2 to confer a long-term advantage on sorted mouse marrow populations in competitive transplantation assays was tested. I found that PGE2-treated short-term (ST)-HSCs, but not long-term (LT)-HSCs show enhanced transplantability in recipients compared to control animals. My studies demonstrate that the effects of PGE2 on HSC function persist over substantial time despite transient exposure. A population of short-term HSCs can engraft and give rise to long-term multilineage reconstitution following PGE2 treatment. Collectively, our studies have led to novel insights regarding the pathways involved in HSC migration, homing, and repopulation.
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Arocena, Miguel. "Control of neural stem cell migration by electric fields." Thesis, University of Aberdeen, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540498.

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Neural stem cells showed strong electrotaxis, evidenced by highly directed migration towards the cathode.  Optimal electrotaxis was found to require growth factors and phosphoinositide 3-kinase (PI3-K) signalling, although reduced electrotaxis could be obtained without growth factors at the highest EFs used.  After EF exposure, neural stem cell trajectories became much more linear, and a reduction in the number of cell protrusions oriented towards the anode was observed.  Also, protrusions initially orienting towards the cathode retracted after the polarity of the EF was reversed, suggesting that EFs could inhibit the extension of anodal protrusions.  A simple model of neural stem cell migration was built with only two key parameters, which reproduced accurately neural stem cell migration patterns, and predicted that PI3-K functions in electrotaxis mainly by controlling cell orientation.  Finally, wild-type and Pax6-/- embryonic neural stem cells were exposed simultaneously to EFs and contact guidance cues in conflicting orientations.  Only wild-type neural stem cells showed significant integrative migratory responses, suggesting that Pax6 is important for integration of diverse guidance cues during cell migration. The results obtained in this thesis show that neural stem cells display strong electrotaxis in vitro, which is accompanied by a qualitative change in the pattern of migration.  The results also identify the control of protrusion orientation by EFs as an important element in neural stem cell electrotaxis, contributing insight into the mechanisms of electrotaxis.  Finally, these results warrant further studies to assess the possibility of using EFs in brain repair therapies.
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Books on the topic "Step migration"

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Filippi, Marie-Dominique, and Hartmut Geiger, eds. Stem Cell Migration. Totowa, NJ: Humana Press, 2011. http://dx.doi.org/10.1007/978-1-61779-145-1.

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Risan, Kareem. Kareem Risan: Steps in migration. Dubai, United Arab Emirates: Meem Gallery, 2014.

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W, Lee Myung, Grow John A, and Geological Survey (U.S.), eds. Some considerations on the steep-dip finite-difference migration. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1985.

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W, Lee Myung, Grow John A, and Geological Survey (U.S.), eds. Some considerations on the steep-dip finite-difference migration. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1985.

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W, Lee Myung, Grow John A, and Geological Survey (U.S.), eds. Some considerations on the steep-dip finite-difference migration. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1985.

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Poudyal, Jyotsna. "They deceived us at every step": Abuse of Cambodian domestic workers migrating to Malaysia. [New York, N.Y.]: Human Rights Watch, 2011.

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Srivastava, Ravi. Small steps lead the way: The Learning and Migration Program (LAMP) of the AIF : a review. New Delhi: American India Foundation, 2010.

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Srivastava, Ravi. Small steps lead the way: The Learning and Migration Program (LAMP) of the AIF : a review. New Delhi: American India Foundation, 2010.

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Harland, James M. Ethnic Identity and the Archaeology of the Aduentus Saxonum. NL Amsterdam: Amsterdam University Press, 2021. http://dx.doi.org/10.5117/9789463729314.

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For centuries, archaeologists have excavated the soils of Britain to uncover finds from the early medieval past. These finds have been used to reconstruct the alleged communities, migration patterns, and expressions of identity of coherent groups who can be regarded as ethnic ‘Anglo-Saxons’. Even in the modern day, when social constructionism has been largely accepted by scholars, this paradigm still persists. This book challenges the ethnic paradigm. As the first historiographical study of approaches to ethnic identity in modern ‘Anglo-Saxon’ archaeology, it reveals these approaches to be incompatible with current scholarly understandings of ethnicity. Drawing upon post-structuralist approaches to self and community, it highlights the empirical difficulties the archaeology of ethnicity in early medieval Britain faces, and proposes steps toward an alternative understanding of the role played by the communities of lowland Britain – both migrants from across the North Sea and those already present – in transforming the Roman world.
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Verma, A. K. SAP BW on HANA Migration: Step by Step Guide on BW Migration to HANA Db. Independently Published, 2018.

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Book chapters on the topic "Step migration"

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Katzer, Matthew. "Step-by-Step Migration." In Securing Office 365, 405–98. Berkeley, CA: Apress, 2018. http://dx.doi.org/10.1007/978-1-4842-4230-8_7.

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Delsemme, J. P., and Ol Zone. "SAMMI: S.A.M.C.E.F. migration onto parallel platforms: Second step." In High-Performance Computing and Networking, 74–81. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/3-540-61142-8_532.

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Olabanji, Daniel, Tineke Fitch, and Olumuyiwa Matthew. "A Step-By-Step Decision Process for Application Migration to Cloud-Native Architecture." In Advances in Information Systems, Artificial Intelligence and Knowledge Management, 63–77. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-51664-1_5.

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Leuzinger-Bohleber, Marianne, Nora Hettich, Mariam Tahiri, and Tamara Fischmann. "STEP-BY-STEP. Ein Pilotprojekt zur Unterstützung von Geflüchteten in der Hessischen Erstaufnahmeeinrichtung Michaelisdorf in Darmstadt." In Flucht, Migration und Trauma: Die Folgen für die nächste Generation, 345–76. Göttingen: Vandenhoeck & Ruprecht, 2017. http://dx.doi.org/10.13109/9783666402845.345.

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Pisarevskaya, Asya, and Peter Scholten. "Towards a Typology of Urban Diversities." In IMISCOE Research Series, 153–82. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-72211-0_8.

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AbstractHow and why do some cities develop such different diversity configurations? And what is the relation between diversity and segregation levels and broader economic situation, migration history and political factors? After the analysis presented the previous chapters we know how 16 selected cities compare to each other in terms of mobilities, inequalities and broader political-institutional setting. However, to understand how these factors are related to diversity and segregation, requires a further step of analysis. To this aim, in this chapter we make the step towards a typology of cities of migration.
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Djelti, Samir, and Ricard Zapata-Barrero. "Transnational Migrant Entrepreneurship Policies in the Maghreb Countries: Tunisia, Algeria, and Morocco." In Migrations in the Mediterranean, 403–18. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-42264-5_23.

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AbstractThis chapter explores how the economic context shapes the Transnational Migrant Entrepreneurship’s (TME) Policies in three different migratory regimes: Tunisia, Algeria, and Morocco. First, the theoretical background, linking the traditional migration and development debate with a more recent discussion linking migration, transnationalism, and entrepreneurship is reviewed. Second, the influence of the economic context on governments’ to adopt TME’s policies is analyzed. Findings have shown that Tunisia has adopted a step-by-step entrepreneurship migration policy building, Algeria has taken a two-in-one entrepreneurship policy for nationals and bi-nationals, and Morocco has chosen to trigger two parallel entrepreneurship policies for both nationals and their migrants living abroad. The discussion of these outcomes has concluded that the interrelation between the economic context and the political realm drive new patterns of TME’s policies in the three Maghreb countries. These findings open a theoretical debate on how the traditional migration/development discussion draws new understandings on the Global South and Global North relations.
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Pisarevskaya, Asya, and Peter Scholten. "Mapping the Diversity of Urban Diversities." In IMISCOE Research Series, 39–49. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-72211-0_3.

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AbstractWhat variation can be identified in urban diversities? In this chapter we provide an empirical mapping of diversity characteristics in cities as outlined in Chap. 2: diversity of origins and residential segregation between people with and without a (first generation) migration background. Can we identify cities that have distinct combinations of the two main dimensions? Inductive analysis in this chapter will provide a second step towards developing a typology of cities of migration. At the end of this chapter, we will identify clusters of cities and select typical cities to be examined more in-depth in subsequent chapters.
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Pisarevskaya, Asya, and Peter Scholten. "Conclusions." In IMISCOE Research Series, 183–95. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-72211-0_9.

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AbstractThe local turn in migration studies has drawn attention to the local level for understanding migration and migration-related diversities (Zapata-Barrero et al., 2017). This book contributes to this turn by revealing a plurality of urban diversities and exploring the factors that contribute to this plurality. Cities of migration come in various types, reflecting different diversity configurations, different locally situated inequalities, and different local approaches. There is no reason for trying to understand the dynamics of migration-related diversity in Paris and Plauen or in Rotterdam and Rouen in similar terms. These cities have very different diversity configurations, migration histories, opportunity structures and political institutional settings. Rather than defining these cities in terms of one urban model our effort is to grasp and understand the complexity of urban diversities. We see this as an important step towards a more differentiated view of urban diversities, and also a insight into the challenges that form in different cities and a better understanding of how and why cities choose different approaches towards governance of migration and diversity. Where Ingolstadt may need an approach very much tailored to the legacy of industrial migration and urban segregation, Hilversum may need an approach that is focused on the whole local population and on the role of diversity across policy sectors and domains.
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Peixoto, João Alvarez, José Antonio Barata Oliveira, André Dionísio Rocha, and Carlos Eduardo Pereira. "The Migration from Conventional Manufacturing Systems for Multi-Agent Paradigm: the First Step." In IFIP Advances in Information and Communication Technology, 111–18. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16766-4_12.

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Fedyuk, Olena, and Violetta Zentai. "The Interview in Migration Studies: A Step towards a Dialogue and Knowledge Co-production?" In IMISCOE Research Series, 171–88. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-76861-8_10.

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Conference papers on the topic "Step migration"

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Huang, Lianjie, and Michael C. Fehler. "Split‐step Padé migration." In SEG Technical Program Expanded Abstracts 2001. Society of Exploration Geophysicists, 2001. http://dx.doi.org/10.1190/1.1816259.

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Bloor, Robert, and Swavek Deregowski. "Variable Depth Step FX Migration." In SEG Technical Program Expanded Abstracts 1996. Society of Exploration Geophysicists, 1996. http://dx.doi.org/10.1190/1.1826664.

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Kessinger, Walter. "Extended split‐step fourier migration." In SEG Technical Program Expanded Abstracts 1992. Society of Exploration Geophysicists, 1992. http://dx.doi.org/10.1190/1.1822254.

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Lewis, G., E. Morris, D. Smith, and L. O'Brien. "Service-Oriented Migration and Reuse Technique (SMART)." In Proceedings. 13th IEEE International Workshop on Software Technology and Engineering Practice. IEEE, 2005. http://dx.doi.org/10.1109/step.2005.24.

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Varma, P. "Stub Libraries for Software Migration and Development." In 13th IEEE International Workshop on Software Technology and Engineering Practice (STEP'05). IEEE, 2005. http://dx.doi.org/10.1109/step.2005.28.

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Tanis, C., P. L. Stoffa, M. K. Sen, and J. T. Fokkema. "Prestack split-step fourier depth migration." In 58th EAEG Meeting. Netherlands: EAGE Publications BV, 1996. http://dx.doi.org/10.3997/2214-4609.201408684.

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Huang, Lianjie, and Michael C. Fehler. "Split‐step Fourier Padé migration method." In SEG Technical Program Expanded Abstracts 2002. Society of Exploration Geophysicists, 2002. http://dx.doi.org/10.1190/1.1816851.

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O'Brien, L., D. Smith, and G. Lewis. "Supporting Migration to Services using Software Architecture Reconstruction." In 13th IEEE International Workshop on Software Technology and Engineering Practice (STEP'05). IEEE, 2005. http://dx.doi.org/10.1109/step.2005.29.

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Zhang, Linbin, James W. Rector, G. Mike Hoversten, and Sergey Fomel. "Split‐step complex Padé—Fourier depth migration." In SEG Technical Program Expanded Abstracts 2004. Society of Exploration Geophysicists, 2004. http://dx.doi.org/10.1190/1.1845333.

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Freire, Raimundo, and Paul L. Stoffa. "Migration using the ‘split‐step fourier” method." In SEG Technical Program Expanded Abstracts 1986. Society of Exploration Geophysicists, 1986. http://dx.doi.org/10.1190/1.1893138.

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Reports on the topic "Step migration"

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Benvenuti, B., C. Marshall-Denton, S. McCann, and Frontières) MSF (Médecins Sans. Death, despair and destitution: the human costs of the EU’s migration policies. Doctors Without Borders/Médecins Sans Frontières, February 2024. http://dx.doi.org/10.57740/jvow8383.

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This report considers the health and humanitarian consequences of violent policies and practices on people moving along EU migration routes. It details findings from MSF medical humanitarian operations in 12 countries in Europe and Africa, as well as in the Central Mediterranean Sea. Taking stock of MSF operational experiences between August 2021 and September 2023, and drawing upon routine medical and operational data from MSF project and accounts from MSF patients and medical teams during that period, the report highlights how, at every step of people’s migration journey towards and within the EU, their health, wellbeing and dignity have been systematically undermined by the interlinking violent policies and practices embedded in EU and EU member state policies.
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Stalder, Lisa, Denise Efionayi-Mäder, and Didier Ruedin. Evaluation des Pilotprojekts STEPS der isa – Fachstelle Migration. Université de Neuchâtel – Swiss Forum for Migration and Population Studies (SFM), March 2024. http://dx.doi.org/10.35662/unine-sfmstudies-87.

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Das Pilotprojekt STEPS – Schritte zum Berufsziel der isa – Fachstelle Migration im Kanton Bern beriet zwischen 2020 und 2023 insgesamt 170 erwachsene Personen mit Migrationserfahrung beim Berufseinstieg oder -wechsel. Das Schweizerische Forum für Migrations- und Bevölkerungsstudien (SFM) der Universität Neuchâtel wurde beauftragt, eine Evaluation von STEPS durchzuführen. Diese Evaluation hat aufgezeigt, dass für ein solches Pilotprojekt eine Nachfrage vorhanden ist und dass die Beratungen durch die befragten Klient·inn·en überwiegend positiv beurteilt werden. Der auf individuelle Bedürfnisse abgestimmte Ansatz von STEPS konnte Migrant·inn·en konkret und mit vielfältigen Methoden auf dem Weg zur Anerkennung von ausländischen Diplomen oder zu einem Schweizer Berufsabschluss unterstützen und durch seine Ressourcen- und Chancenorientierung auch zur sozialen Anerkennung beitragen. Allerdings erwies sich die Zusammenarbeit zwischen STEPS und weiteren Angeboten in der Anerkennungs-, Bildungs- und Berufsberatung im Kanton Bern auch im Kontext der Covid-19 Pandemie und aufgrund unterschiedlicher institutioneller Logiken als Herausforderung. Die Erfahrungen aus dem Pilotprojekt zeigen aber wichtige Lücken und Handlungsmöglichkeiten auf, welche nicht nur in Bezug auf ein migrantisches Zielpublikum sondern auch allgemein für die Beratungstätigkeit in den Bereichen Bildung und Beruf von Bedeutung sein können.
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Kudin, Roman, Niranjan Singh, Prabhat Chand, Anura Bakmeedeniya, and Jone Tawaketini. Estimating Emissions from Tyre Tread Wear of Motor Vehicles. Unitec ePress, July 2024. http://dx.doi.org/10.34074/ocds.108.

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Over 5.6 million road vehicles are registered in New Zealand, with a wide range of contaminants released as a result of their operation. The material wearing out from tyre tread has previously been identified as a contaminant of potential concern (COPC) in New Zealand, but its amount has not been quantified. Numerous studies confirm that the wear rate of a tyre depends on multiple factors and can vary significantly, even for the same type of vehicle with the same tyres installed. Such factors have already been classified and weighted; therefore, they were not the subject of the current research. The aim of this study is to estimate the total amount of material released into the environment in New Zealand due to the tread wear of tyres. In this research, the New Zealand motor vehicle fleet was divided into categories according to the available statistical data. The estimation of the amount of the tyre material released into the environment was done separately in each category of vehicle, using the three-point method (Low, Medium and High). The calculation was performed using the statistical average annual distances driven by vehicles, and the tyre abrasion rates, also called emission factors (mg/km). The emission factors were adopted through a thorough review of the available studies of tyre abrasion rates in different countries. The three-point estimate shows that every year roughly 6.5 to 15.5 thousand tonnes of material from tyre tread wear is released into the environment in New Zealand, which gives between 1.26 and 2.97 kg when converted per capita. Such quantification is an important step in understanding the impacts of this contaminant on New Zealand ecosystems. Further research of tyre tread wear material is needed with regard to its emission factors; deposition, migration and concentrations in environmental compartments; accumulation and degradation paths; effects on living organisms and human health.
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Bai, John (Jianqiu), William Kerr, Chi Wan, and Alptug Yorulmaz. Everyone Steps Back? The Widespread Retraction of Crowd-Funding Support for Minority Creators when Migration Fear is High. Cambridge, MA: National Bureau of Economic Research, November 2024. http://dx.doi.org/10.3386/w33097.

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Davies, Will. Improving the engagement of UK armed forces overseas. Royal Institute of International Affairs, January 2022. http://dx.doi.org/10.55317/9781784135010.

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The UK government’s Integrated Review of security, defence, development and foreign policy, published in March 2021 alongside a supporting defence command paper, set a new course for UK national security and highlighted opportunities for an innovative approach to international engagement activity. The Integrated Review focused principally on the state threats posed by China’s increasing power and by competitors – including Russia – armed with nuclear, conventional and hybrid capabilities. It also stressed the continuing risks to global security and resilience due to conflict and instability in weakened and failed states. These threats have the potential to increase poverty and inequality, violent extremism, climate degradation and the forced displacement of people, while presenting authoritarian competitors with opportunities to enhance their geopolitical influence. There are moral, security and economic motives to foster durable peace in conflict-prone and weakened regions through a peacebuilding approach that promotes good governance, addresses the root causes of conflict and prevents violence, while denying opportunities to state competitors. The recent withdrawal from Afghanistan serves to emphasize the complexities and potential pitfalls associated with intervention operations in complex, unstable regions. Success in the future will require the full, sustained and coordinated integration of national, allied and regional levers of power underpinned by a sophisticated understanding of the operating environment. The UK armed forces, with their considerable resources and global network, will contribute to this effort through ‘persistent engagement’. This is a new approach to overseas operations below the threshold of conflict, designed as a pre-emptive complement to warfighting. To achieve this, the UK Ministry of Defence (MOD) must develop a capability that can operate effectively in weak, unstable and complex regions prone to violent conflict and crises, not least in the regions on the eastern and southern flanks of the Euro-Atlantic area. The first step must be the development of a cohort of military personnel with enhanced, tailored levels of knowledge, skills and experience. Engagement roles must be filled by operators with specialist knowledge, skills and experience forged beyond the mainstream discipline of combat and warfighting. Only then will individuals develop a genuinely sophisticated understanding of complex, politically driven and sensitive operating environments and be able to infuse the design and delivery of international activities with practical wisdom and insight. Engagement personnel need to be equipped with: An inherent understanding of the human and political dimensions of conflict, the underlying drivers such as inequality and scarcity, and the exacerbating factors such as climate change and migration; - A grounding in social sciences and conflict modelling in order to understand complex human terrain; - Regional expertise enabled by language skills, cultural intelligence and human networks; - Familiarity with a diverse range of partners, allies and local actors and their approaches; - Expertise in building partner capacity and applying defence capabilities to deliver stability and peace; - A grasp of emerging artificial intelligence technology as a tool to understand human terrain; - Reach and insight developed through ‘knowledge networks’ of external experts in academia, think-tanks and NGOs. Successful change will be dependent on strong and overt advocacy by the MOD’s senior leadership and a revised set of personnel policies and procedures for this cohort’s selection, education, training, career management, incentivization, sustainability and support.
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Bulatetska, Lesya V., Vitaliy V. Bulatetskyi, Tetyana O. Hryshanovych, Yulia S. Pavlenko, Tetyana I. Cheprasova, and Andrey V. Pikilnyak. Operation system features and cloud services for lecturer work. [б. в.], June 2021. http://dx.doi.org/10.31812/123456789/4443.

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The work proposes a conception of setup and use of teacher’s or lecturer’s workspace using common software and hardware products. The research object is a system built by using operating system capabilities in conjunction with office suite and public cloud service, as a foundation for teacher’s digital workspace. Research is made on how to set up, scale, and operate such a system, by studying the experience of national and foreign scientists and teachers, and using our own experience in educational processes, and working with operating systems and cloud services. As a result, we got a system which is easy to set up, learn, and apply by teachers without significant experience working remote education systems, and could be used for initial learning of remote education principles. It could be used as an initial step before migrating to specialized remote education systems. In the future, the system itself could be improved by adding additional objects into the system and a higher integration level between objects and external subjects.
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McClure, Michael A., Yitzhak Spiegel, David M. Bird, R. Salomon, and R. H. C. Curtis. Functional Analysis of Root-Knot Nematode Surface Coat Proteins to Develop Rational Targets for Plantibodies. United States Department of Agriculture, October 2001. http://dx.doi.org/10.32747/2001.7575284.bard.

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The goal of this research was to provide a better understanding of the interface between root-knot nematodes, Meloidogyne spp., and their host in order to develop rational targets for plantibodies and other novel methods of nematode control directed against the nematode surface coat (SC). Specific objectives were: 1. To produce additional monoclonal SC antibodies for use in Objectives 2, 3, and 4 and as candidates for development of plantibodies. 2. To determine the production and distribution of SC proteins during the infection process. 3. To use biochemical and immunological methods to perturbate the root-knot nematode SC in order to identify SC components that will serve as targets for rationally designed plantibodies. 4. To develop SC-mutant nematodes as additional tools for defining the role of the SC during infection. The external cuticular layer of nematodes is the epicuticle. In many nematodes, it is covered by a fuzzy material termed "surface coat" (SC). Since the SC is the outermost layer, it may playa role in the interaction between the nematode and its surroundings during all life stages in soil and during pathogenesis. The SC is composed mainly of proteins, carbohydrates (which can be part of glycoproteins), and lipids. SC proteins and glycoproteins have been labeled and extracted from preparasitic second-stage juveniles and adult females of Meloidogyne and specific antibodies have been raised against surface antigens. Antibodies can be used to gain more information about surface function and to isolate genes encoding for surface antigens. Characterization of surface antigens and their roles in different life-stages may be an important step towards the development of alternative control. Nevertheless, the role of the plant- parasitic nematode's surface in plant-nematode interaction is still not understood. Carbohydrates or carbohydrate-recognition domains (CROs) on the nematode surface may interact with CROs or carbohydrate molecules, on root surfaces or exudates, or be active after the nematode has penetrated into the root. Surface antigens undoubtedly play an important role in interactions with microorganisms that adhere to the nematodes. Polyclonal (PC) and monoclonal (MC) antibodies raised against Meloidogyne javanica, M. incognita and other plant-parasitic nematodes, were used to characterize the surface coat and secreted-excreted products of M. javanica and M. incognita. Some of the MC and PC antibodies raised against M. incognita showed cross-reactivity with the surface coat of M. javanica. Further characterization, in planta, of the epitopes recognized by the antibodies, showed that they were present in the parasitic juvenile stages and that the surface coat is shed during root penetration by the nematode and its migration between root cells. At the molecular level, we have followed two lines of experimentation. The first has been to identify genes encoding surface coat (SC) molecules, and we have isolated and characterized a small family of mucin genes from M. incognita. Our second approach has been to study host genes that respond to the nematode, and in particular, to the SC. Our previous work has identified a large suite of genes expressed in Lycopersicon esculentum giant cells, including the partial cDNA clone DB#131, which encodes a serine/threonine protein kinase. Isolation and predicted translation of the mature cDNA revealed a frame shift mutation in the translated region of nematode sensitive plants. By using primers homologous to conserved region of DB#131 we have identified the orthologues from three (nematode-resistant) Lycopersicon peruvianum strains and found that these plants lacked the mutation.
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Abdullah, Hannah, Karim Elgendy, and Hanne Knaepen. Climate Resilience in Cities of the EU’s Southern Neighbourhood: Opportunities for the EU Green Deal. The Royal Institute of International Affairs, November 2021. http://dx.doi.org/10.55317/casc016.

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Cities in the Middle East and North Africa are already suffering the effects of climate change. Weak urban regulation, ineffective climate policies, limited decentralization and insufficient empowerment of local authorities and civil society further decrease urban resilience. Future climate scenarios and projected urban growth threaten the stability of the region; with potential negative knock-on effects on Europe. This CASCADES Spotlight Study examines climate vulnerabilities in urban areas in countries to the south of the EU and the wider Middle East and North Africa region and advocates for systemic approaches to addressing urban climate resilience by strengthening the water-energy-food nexus, as well as other enabling factors such as decentralization. It concludes with recommendations on how the European Green Deal can help cities in the region adapt to climate impacts, based on a water-energy-food nexus approach. Over the past two decades, the European Commission has stepped up its support for urban climate action and resilience. An increasing number of programmes financed under the European Neighbourhood Policy (ENP) South have addressed urban climate resilience in response to the region’s rapid urbanization and the high climate vulnerability of cities. The number of urban dwellers in the wider Middle East and North Africa region is estimated to reach 527 million in 2050, an increase of 72% compared to 2020. At the same time, climate impacts – including both slow onset changes and sudden disasters – are putting additional stress on urban infrastructure. This stress is aggravated by weak urban regulations that have created unsustainable development trends which undermine the potential benefits of urbanization and adversely affect urban climate resilience. The prevalence of highly centralized administrative systems and incomplete decentralization reforms hamper local capacity building and decision-making, which are prerequisites for effective adaptation and resilience. At the same time, climate impacts – including both slow onset changes and sudden disasters – are putting additional stress on urban infrastructure. This stress is aggravated by weak urban regulations that have created unsustainable development trends which undermine the potential benefits of urbanization and adversely affect urban climate resilience. The prevalence of highly centralized administrative systems and incomplete decentralization reforms hamper local capacity building and decision-making, which are prerequisites for effective adaptation and resilience. The convergence of the region’s harsh climatic conditions with rapid, unsustainable urbanization and the associated socio-economic burdens can exacerbate existing political instability, conflict-induced migration and poverty. These developments could cascade into the EU, altering security, trade and diplomatic relations with the Southern Neighbourhood. The EU’s evolving approach to working with local authorities on urban infrastructure and climate governance is a first step towards addressing the region’s intertwined urban and climate crises. However, this approach is still in the early stages and there is a need to reflect on lessons learned and how urban spaces, climates and governance are evolving in the region. This study suggests that the EU’s overwhelming focus on supporting cities in the region with energy efficiency and the transition to sustainable energy systems is not enough to strengthen urban climate resilience. In cities of the Southern Neighbourhood, which typically struggle with resource management and scarcity, climate resilience will increasingly depend on local capacities to formulate and implement nexus approaches, especially in the water, energy and food sectors. Based on case studies of three small and intermediary urban areas, the study advocates for a systemic approach to addressing urban climate resilience in Southern Neighbourhood cities. Considering the established effectiveness of applying a water-energy-food nexus approach to improving climate resilience, the paper stresses the need for local governments to explore nexus opportunities between the water, energy and food sectors in order to achieve resilient and sustainable urbanism, while also highlighting other enabling factors such as decentralization. It concludes by exploring how future external action around the European Green Deal and its ambitions for systemic transformation could benefit from stepping up cooperation with cities in the Southern Neighbourhood around the water-energy-food nexus.
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Aguiar, Angel, and Terrie Walmsley. The Importance of Timing in the U.S. response to Undocumented Immigrants: A Recursive Dynamic Approach. GTAP Working Paper, May 2013. http://dx.doi.org/10.21642/gtap.wp75.

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In an attempt to control the flow of undocumented immigrants, successive US governments have considered everything from large scale deportation, amnesties, expanding visa programs, to fining firms who hire illegal workers. Using a comparative static model, Aguiar and Walmsley (2013), find that amnesties have a positive impact on the US economy. However such policies are one-time changes in the labor force, whose benefits diminish over time, and which are unlikely to stem the flow of undocumented workers or fulfill the demands of U.S. firms for cheap foreign labor. In this paper we use a global dynamic model to investigate the long run implications of three alternative policy scenarios: 1) a one-time amnesty for undocumented workers living in the US; 2) a permanent increase in the number of foreign worker visas; and 3) enhanced border security. We find that an amnesty is much less effective than a permanent increase in visas at promoting growth in the U.S., while enhanced border control by the U.S. is beneficial for Mexico in terms real GDP. Key words: Global Dynamic General Equilibrium Model, USA Migration Policy, Permanent, One-off temporary policy changes, undocumented migrants.
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Siegel, David A., Ivona Cetinic, Andrew F. Thompson, Norman B. Nelson, Michaela Sten, Melissa Omand, Shawnee Traylor, et al. EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) North Atlantic sensor calibration and intercalibration documents. NASA STI Program and Woods Hole Oceanographic Institution, October 2023. http://dx.doi.org/10.1575/1912/66998.

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The following documents collect information regarding the calibration and intercalibration of various sensors that were deployed during the North Atlantic field component of the NASA EXPORTS project (EXPORTS NA), which took place between May 4 and June 1, 2021 (Johnson et al., 2023). The EXPORTS NA campaign was designed to to provide a contrasting end member to the earlier North Pacific field campaign, and focused on carbon export associated with the North Atlantic spring bloom in which gravitational sinking of organic particles, the physical advection and mixing, and active transport by vertically migrating zooplankton are all expected to provide significant flux pathways. During EXPORTS NA data sets were collected from a variety of shipbased, autonomously-piloted, and Lagrangian platforms. Intercalibration activities were tasked to different groups within the EXPORTS project team. Team leads and contact information are listed below. The overarching goal of these activities was to identify a trusted sensor, carry out a careful calibration of this sensor, then base any intercalibraiton needs off of this sensor, occasionally propagating information across platforms. Full details of the intercalibration approach, assumptions, and summary are provided in the attached documents. All calibration and intercalibration activities were completed before data set were uplaoded to the NASA SeaBASS data repository. Data related to this cruise can be publicly accessed at: https://seabass.gsfc.nasa.gov/cruise/EXPORTSNA Updates to calibration and intercalibration documents required to reflect revised data sets will also be provided through SeaBASS. Questions concerning referencing these documents or accessing data sets should be directed to Inia Soto Ramos. NASA EXPORTS Science Lead: David Siegel, davesiegel@ucsb.edu NASA EXPORTS Project Scientist: Ivona Cetini´c, ivona.cetinic@nasa.gov NASA EXPORTS Data Manager: Inia Soto Ramos, inia.m.sotoramos@nasa.gov Calibration and intercalibration leads Temperature and salinity sensors: Andy Thompson, andrewt@caltech.edu Chlorophyll fluorescence sensors: Melissa Omand & Kaley Sten, momand@uri.edu Oxygen sensors: Shawnee Traylor & Roo Nicholson, shawnee@mit.edu Optical backscatter sensors: Xiaodong Zhang, Xiaodong.Zhang@usm.edu Lagrangian float sensors: Eric D’Asaro, dasaro@apl.washington.edu Underway sensors: Leah Johnson, leahjohn@uw.edu Underwater Vision Profiler (UVP)-Particle Size Distribution (PSD): David Siegel, davesiegel@ucsb.edu
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