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See detailThe spatial Solow model
Camacho, Camen; Zou, Benteng UL

in Economics Bulletin (2004)

In this paper, we solve a Solow model in continuous time and space. We prove the existence of a solution to the problem and its convergence to a stationary solution. The simulations of various scenario in ... [more ▼]

In this paper, we solve a Solow model in continuous time and space. We prove the existence of a solution to the problem and its convergence to a stationary solution. The simulations of various scenario in the last section of the paper illustrates the convergence issue. [less ▲]

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See detailSpatial sorting, attitudes and the use of green space in Brussels
Schindler, Mirjam; Le Texier, Marion; Caruso, Geoffrey UL

in Urban Forestry and Urban Greening (2018), 31

Extensive evidence exists on the benefits provided by urban green space (UGS) but evidence is lacking about whether and how socio-economic benefits accrue to all residents or disproportionally depending ... [more ▼]

Extensive evidence exists on the benefits provided by urban green space (UGS) but evidence is lacking about whether and how socio-economic benefits accrue to all residents or disproportionally depending on their socio-economic status or residential location. We model joint effects of socio-economic and locational attributes on attitudes and use of UGS in Brussels (BE). The analysis is based on a survey conducted along an urban-suburban continuum with respondents sampled across non-park public space. Patterns of use are depicted by the frequency and the distance travelled to the most used UGS. Attitudes are analysed along three dimensions: willingness to (i) pay for UGS, (ii) trade-off housing for green space and (iii) substitute private for public green. Our results stress the importance of separating effects of attitudes from socio-economic and locational effects to quantify UGS use, and suggest endogenous effects of green space with residential sorting. [less ▲]

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See detailSpatial Sparsity Based Direct Positioning for IR-UWB in IEEE 802.15.4a Channels
Lagunas, Eva UL; Najar, Montse; Navarro, Monica et al

in IEEE Int. Conf. UltraWide-Band (ICUWB) (2014)

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See detailA spatially constrained generative model and an EM algorithm for image segmentation
Diplaros, Aristeidis; Vlassis, Nikos UL; Gevers, Theo

in IEEE Transactions on Neural Networks (2007), 18(3), 798-808

In this paper, we present a novel spatially constrained generative model and an expectation-maximization (EM) algorithm for model-based image segmentation. The generative model assumes that the unobserved ... [more ▼]

In this paper, we present a novel spatially constrained generative model and an expectation-maximization (EM) algorithm for model-based image segmentation. The generative model assumes that the unobserved class labels of neighboring pixels in the image are generated by prior distributions with similar parameters, where similarity is defined by entropic quantities relating to the neighboring priors. In order to estimate model pa rameters from observations, we derive a spatially constrained EM algorithm that iteratively maximizes a lower bound on the data log-likelihood, where the penalty term is data-dependent. Our algorithm is very easy to implement and is similar to the standard EM algorithm for Gaussian mixtures with the main difference that the labels posteriors are "smoothed" over pixels between each E-and M-step by a standard image filter. Experiments on synthetic and real images show that our algorithm achieves competitive segmentation results compared to other Markov-based methods, and is in general faster. [less ▲]

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See detailSpatially Differentiated, Temporally Variegated: The Study of Life Cycles for a Better Understanding of Suburbia in German City Regions
Hesse, Markus UL; Polivka, Jan; Reicher, Christa

in Raumforschung und Raumordnung (2017), 76(2), 149-163

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See detailSpatially resolved measurements of depletion properties of large gate two-dimensional electron gas semiconductor terahertz modulators
Kleine-Ostmann, T.; Pierz, K.; Hein, G. et al

in Journal of Applied Physics (2009), 105(9), 093707-1-093707-6

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See detailSpatially resolved raman spectroscopy of single- and few-layer graphene
Graf, D.; Molitor, F.; Ensslin, K. et al

in Nano Letters (2007), 7(2), 238-242

We present Raman spectroscopy measurements on single- and few-layer graphene flakes. By using a scanning confocal approach, we collect spectral data with spatial resolution, which allows us to directly ... [more ▼]

We present Raman spectroscopy measurements on single- and few-layer graphene flakes. By using a scanning confocal approach, we collect spectral data with spatial resolution, which allows us to directly compare Raman images with scanning force micrographs. Single-layer graphene can be distinguished from double- and few-layer by the width of the D' line: the single peak for single-layer graphene splits into different peaks for the double-layer. These findings are explained using the double-resonant Raman model based on ab initio calculations of the electronic structure and of the phonon dispersion. We investigate the D line intensity and find no defects within the flake. A finite D line response originating from the edges can be attributed either to defects or to the breakdown of translational symmetry. [less ▲]

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See detailSpatial–temporal variations of water vapor content over Ethiopia: a study using GPS observations and the ECMWF model
Abraha, Kibrom Ebuy UL; Lewi, Elias; Masson, Frederic et al

in GPS Solutions (2015)

We characterize the spatial–temporal variability of integrated water vapor (IWV) in Ethiopia from a network of global positioning system (GPS) stations and the European Center for Medium range Weather ... [more ▼]

We characterize the spatial–temporal variability of integrated water vapor (IWV) in Ethiopia from a network of global positioning system (GPS) stations and the European Center for Medium range Weather Forecasting (ECMWF) model. The IWV computed from the ECMWF model is integrated from the height of the GPS stations on 60 pressure levels to take both the actual earth surface and the model orography discrepancies into account. First, we compare the IWV estimated from GPS and from the model. The bias varies from site to site, and the correlation coefficients between the two data sets exceed 0.85 at different time scales. The results of this study show that the general ECMWF IWV trend is underestimation over highlands and overestimation over lowlands for wet periods, and overestimation over high- lands and underestimation over lowlands for dry periods with very few exceptional stations. Second, we observe the spatial variation of the IWV. High values are obtained in those stations that are located in the north-eastern (Afar depression) sites and the south-western part of the country. This distribution is related to the spatial variability of the climate in Ethiopia. Finally, we study the seasonal cycle and inter-annual variability of IWV for all stations over Ethiopia. The main result is the strong inter-annual vari- ability observed for the dry seasons. [less ▲]

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See detailSpatio-temporal activation of chromatin on the human CYP24 gene promoter in the presence of 1alpha,25-Dihydroxyvitamin D3
Väisänen, Sami; Dunlop, Thomas W.; Sinkkonen, Lasse UL et al

in Journal of Molecular Biology (2005), 350(1), 65-77

The vitamin D3 24-hydroxylase gene (CYP24) is one of the most strongly induced genes known. Despite this, its induction by the hormone 1alpha,25-dihydroxyvitamin D3 (1alpha,25OH2D3) has been characterized ... [more ▼]

The vitamin D3 24-hydroxylase gene (CYP24) is one of the most strongly induced genes known. Despite this, its induction by the hormone 1alpha,25-dihydroxyvitamin D3 (1alpha,25OH2D3) has been characterized only partially. Therefore, we monitored the spatio-temporal, 1alpha,25OH2D3-dependent chromatin acetylation status of the human CYP24 promoter by performing chromatin immunoprecipitation (ChIP) assays with antibodies against acetylated histone 4. This was achieved by performing PCR on 25 contiguous genomic regions spanning the first 7.7 kb of the promoter. ChIP assays using antibodies against the 1alpha,25OH2D3 receptor (VDR) revealed that, in addition to the proximal promoter, three novel regions further upstream associated with VDR. Combined in silico/in vitro screening identified in three of the four promoter regions sequences resembling known VDREs and reporter gene assays confirmed the inducibility of these regions by 1alpha,25OH2D3)=. In contrast, the fourth VDR-associated promoter region did not contain any recognizable classical VDRE that could account for the presence of the protein on this region. However, re-ChIP assays monitored on all four promoter regions simultaneous association of VDR with retinoid X receptor, coactivator, mediator and RNA polymerase II proteins. These proteins showed a promoter region-specific association pattern demonstrating the complex choreography of the CYP24 gene promoter activation over 300 minutes. Thus, this study reveals new information concerning the regulation of the CYP24 gene by 1alpha,25OH2D3, and is a demonstration of the simultaneous participation of multiple, structurally diverse response elements in promoter activation in a living cell. [less ▲]

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See detailThe spatio-temporal correlates of holistic face perception
Schiltz, Christine UL; Jacques, Corentin; Rossion, Bruno

Poster (2007, May)

It is well known that faces are perceived holistically: their parts are integrated into a global or so-called holistic individual representation. Here we clarify where and how early in time individual ... [more ▼]

It is well known that faces are perceived holistically: their parts are integrated into a global or so-called holistic individual representation. Here we clarify where and how early in time individual holistic representations are extracted from the visual stimulus, by means of an event-related identity adaptation paradigm in fMRI (study 1; 10 subjects) and ERPs (study 2; 16 subjects). During blocks, subjects were presented with trials made of two sequentially presented faces and performed a same/different judgement on the top parts of each pair of faces. Face parts were presented either aligned or misaligned. For each face pair, the identity of top and bottom parts could be (a) both identical, (b) both different, (c) different only for the bottom part. The latter manipulation resulted in a strong face composite illusion behaviourally, i.e. the perception of identical top parts as being different, only in the aligned format. In the face-sensitive area of the middle fusiform gyrus (‘fusiform face area’) we observed a stronger response to the top part perceived as being different (release from adaptation), but only when the top and the bottom parts were aligned. It is consistent with the illusion of viewing different top parts of faces, and this release from fMR-adaptation is similar to the one observed in the ‘different’ condition for both aligned and misaligned parts. The same observations were made in ERPs as early as 150 ms, the amplitude of the electrophysiological response at occipito-temporal sites to the second face stimulus being reduced for identical relative to different top face parts, and to identical top parts perceived as different (aligned - bottom different). With both methods, the effects were stronger in the right hemisphere. Altogether, these observations indicate that individual faces are perceived holistically as early as 150 ms in the occipito-temporal cortex. [less ▲]

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See detailSpatio-temporal distribution of chondromodulin-I mRNA in the chicken embryo: expression during cartilage development and formation of the heart and eye.
Dietz, U. H.; Ziegelmeier, G.; Bittner, K. et al

in Developmental Dynamics : An Official Publication of the American Association of Anatomists (1999), 216(3), 233-43

To define genes specifically expressed in cartilage and during chondrogenesis, we compared by differential display-polymerase chain reaction (DD-PCR) the mRNA populations of differentiated sternal ... [more ▼]

To define genes specifically expressed in cartilage and during chondrogenesis, we compared by differential display-polymerase chain reaction (DD-PCR) the mRNA populations of differentiated sternal chondrocytes from chicken embryos with mRNA species modulated in vitro by retinoic acid (RA). Chondrocyte-specific gene expression is downregulated by RA, and PCR-amplified cDNAs from both untreated and RA-modulated cells were differentially displayed. Amplification products only from RNA of untreated chondrocytes were further analyzed, and a cDNA-fragment of the chondromodulin-I (ChM-I) mRNA was isolated. After obtaining full length cDNA clones, we have analyzed the mRNA expression patterns at different developmental stages by RNase protection assay and in situ hybridization. Analysis of different tissues and cartilage from 17-day-old chicken embryos showed ChM-I mRNA only in chondrocytes. During somitogenesis of the chicken embryo, ChM-I transcripts were detected in the notochord, the floor and the roof plate of the neural tube, and in cartilage precursor tissues such as the sclerotomes of the somites, the developing limbs, the pharyngeal arches, the otic vesicle, and the sclera. ChM-I continued to be expressed in differentiated cartilages derived from these tissues and also in noncartilaginous domains of the developing heart and retina. Thus, in the chicken, the expression of ChM-I is not restricted to mature cartilage but is already present during early development in precartilaginous tissues as well as in heart and eye. [less ▲]

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See detailSpatio-temporal ToF data enhancement by fusion
Garcia, F.; Aouada, D.; Mirbach, B. et al

in Proceedings - International Conference on Image Processing, ICIP (2012)

We propose an extension of our previous work on spatial domain Time-of-Flight (ToF) data enhancement to the temporal domain. Our goal is to generate enhanced depth maps at the same frame rate of the 2-D ... [more ▼]

We propose an extension of our previous work on spatial domain Time-of-Flight (ToF) data enhancement to the temporal domain. Our goal is to generate enhanced depth maps at the same frame rate of the 2-D camera that, coupled with a ToF camera, constitutes a hybrid ToF multi-camera rig. To that end, we first estimate the motion between consecutive 2-D frames, and then use it to predict their corresponding depth maps. The enhanced depth maps result from the fusion between the recorded 2-D frames and the predicted depth maps by using our previous contribution on ToF data enhancement. The experimental results show that the proposed approach overcomes the ToF camera drawbacks; namely, low resolution in space and time and high level of noise within depth measurements, providing enhanced depth maps at video frame rate. © 2012 IEEE. [less ▲]

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See detailSpatio-Temporal ToF Data Enhancement by Fusion
Garcia Becerro, Frederic UL; Aouada, Djamila UL; Mirbach, Bruno et al

in 19th IEEE International Conference on Image Processing (2012)

Detailed reference viewed: 58 (5 UL)
See detailSpätmittelalterliche Fronarbeiten im Dienst der Stadt Luxemburg
Pauly, Michel UL

in Ebeling, Dietrich; Henn, Volker; Holbach, Rudolf (Eds.) et al Landesgeschichte als multidisziplinäre Wissenschaft. Festgabe für Franz Irsigler zum 60. Geburtstag (2001)

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See detailSpätmittelalterliche Städte in der Großregion SaarLor-Lux (1180-1500)
Penny, Alain; Pauly, Michel UL; Caruso, Geoffrey UL et al

E-print/Working paper (2010)

Aufgrund von unterschiedlichen natürlichen, politischen und wirtschaftlichen Voraussetzungen lassen sich deutliche Unterschiede in der räumlichen Verteilung und zeitlichen Entwicklung der ... [more ▼]

Aufgrund von unterschiedlichen natürlichen, politischen und wirtschaftlichen Voraussetzungen lassen sich deutliche Unterschiede in der räumlichen Verteilung und zeitlichen Entwicklung der spätmittelalterlichen Städte in der Großregion feststellen. In der Karte "Spätmittelalterliche Städte" sind die Siedlungen dargestellt, die im späten Mittelalter, das heißt in der Zeit zwischen dem frühen 13. Jahrhundert und dem Jahr 1500, als Städte bezeichnet werden konnten. Ausschlaggebend dafür ist die Erfüllung einer Reihe von Kriterien, die durch die Definition der mittelalterlichen Stadt vorgegeben werden. [less ▲]

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See detailSpaßguerilla : Über die humoristische Dimension des politischen Aktivismus
Doll, Martin UL

in Kaul, Susanne; Kohns, Oliver (Eds.) Politik und Ethik der Komik (2012)

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See detailSpecial edition on constructing Banking Union: Introduction
Howarth, David UL; Schild, Joachim

in Journal of Economic Policy Reform (2018), 21(2), 99-110

European Banking Union arguably represents the most important step in European economic integration since the launch of Monetary Union. Little wonder, then, that this major deepening of integration ... [more ▼]

European Banking Union arguably represents the most important step in European economic integration since the launch of Monetary Union. Little wonder, then, that this major deepening of integration sparked a lively academic debate and triggered an ever-growing number of publications from different disciplinary backgrounds. The first wave of publications on European Banking Union (BU) provided us with overviews on the legal changes; they discussed at length the economic rationale underpinning BU; and they traced the political dynamics of establishing BU discussing key explanatory factors. This literature reflected BU’s foundational phase between 2012 and 2014 when the major texts enshrining BU in law were negotiated and adopted. This special issue is located at the intersection of this first phase and a second stage of research covering different topics as regards to the functioning of BU. New research questions are triggered by the — so far still limited — experiences regarding BU’s implementation and current operation. Based on this empirical evidence, contributions to this second wave of BU-related research try to identify potentially dangerous lacunae and design faults, contributing to the ongoing reform debates. Taken together, the contributions to this special issue provide us with a nuanced picture of Banking Union’s construction problems, lacunae, and governance structure design faults. Banking Union resembles an unfinished cathedral. Given its problematic architecture, there remain important stability risks. [less ▲]

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See detailSpecial Education and the Risk of Becoming Less Educated
Powell, Justin J W UL

in European Societies (2006), 8(4), 577-599

With educational expansion and rising standards, ever more students are being transferred into special education. These programs serve children and youth with ‘special educational needs’ (SEN), a ... [more ▼]

With educational expansion and rising standards, ever more students are being transferred into special education. These programs serve children and youth with ‘special educational needs’ (SEN), a heterogeneous group with social, ethnic, linguistic, physical, and intellectual disadvantages. An increasing proportion of students at risk of leaving secondary school without qualifications participate in special education. While most European countries aim to replace segregated schools and separate classes with school integration and inclusive education, cross-national comparisons of special education’s diverse student bodies show considerable disparities in rates of SEN classification, provided learning opportunities, and educational attainments. Analyses of European special education demographics and organizations emphasize institutional instead of individual explanations. Findings from Germany and the United States further demonstrate that which students bear the greatest risk of becoming less educated depends principally on the institutionalization of special education systems and on definitions of ‘special educational needs’. [less ▲]

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See detailSpecial Education and the Risk of Becoming Less Educated in Germany and the US
Powell, Justin J W UL

E-print/Working paper (2004)

Detailed reference viewed: 29 (2 UL)