Littérature scientifique sur le sujet « DEM of Difference »
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Articles de revues sur le sujet "DEM of Difference"
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Bhardwaj, Ashutosh, Kamal Jain et Rajat Subhra Chatterjee. « Refining IKONOS DEM for Dehradun Region Using Photogrammetry Based DEM Editing Methods, Orthoimage Generation and Quality Assessment of Cartosat-1 DEM ». Environmental Sciences Proceedings 5, no 1 (2 décembre 2020) : 3. http://dx.doi.org/10.3390/iecg2020-06966.
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The correct representation of the topography of terrain is an important requirement to generate photogrammetric products such as orthoimages and maps from high-resolution (HR) or very high-resolution (VHR) satellite datasets. The refining of the digital elevation model (DEM) for the generation of an orthoimage is a vital step with a direct effect on the final accuracy achieved in the orthoimages. The refined DEM has potential applications in various domains of earth sciences such as geomorphological analysis, flood inundation mapping, hydrological analysis, large-scale mapping in an urban environment, etc., impacting the resulting output accuracy. Manual editing is done in the presented study for the automatically generated DEM from IKONOS data consequent to the satellite triangulation with a root mean square error (RMSE) of 0.46, using the rational function model (RFM) and an optimal number of ground control points (GCPs). The RFM includes the rational polynomial coefficients (RPCs) to build the relation between image space and ground space. The automatically generated DEM initially represents the digital surface model (DSM), which is used to generate a digital terrain model (DTM) in this study for improving orthoimages for an area of approximately 100 km2. DSM frequently has errors due to mass points in hanging (floating) or digging, which need correction while generating DTM. The DTM assists in the removal of the geometric effects (errors) of ground relief present in the DEM (i.e., DSM here) while generating the orthoimages and thus improves the quality of orthoimages, especially in areas such as Dehradun that have highly undulating terrain with a large number of natural drainages. The difference image of reference, i.e., edited IKONOS DEM (now representing DTM) and automatically generated IKONOS DEM, i.e., DSM, has a mean difference of 1.421 m. The difference DEM (dDEM) for the reference IKONOS DEM and generated Cartosat-1 DEM at a 10 m posting interval (referred to as Carto10 DEM) results in a mean difference of 8.74 m.
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Frankenberg, Elizabeth, et Duncan Thomas. « Women's Health and Pregnancy Outcomes : Do Services Make a Difference ? » Demography 38, no 2 (2001) : 253–65. http://dx.doi.org/10.1353/dem.2001.0014.
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London, Andrew S., et Cheryl Elman. « The Influence of Remarriage on the Racial Difference in Mother-Only Families in 1910 ». Demography 38, no 2 (2001) : 283–97. http://dx.doi.org/10.1353/dem.2001.0017.
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Zhou, Zhu Bo, Hong Zhang Ma, Xiao Bo Zhu et Lin Sun. « Comparative Analysis of Forest Height Retrieval Methods by Polarimetric SAR Interferometry ». Advanced Materials Research 726-731 (août 2013) : 4686–89. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.4686.
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The objective of this paper is to compare and analyze the forest height retrieval methods from Polarimetric SAR Interferometry(POLINSAR).Both of the methods based on DEM difference and that on interferometry coherence amplitude are generalized, analyzed, and compared.Also in this paper combined methods of DEM difference and interferometry coherence amplitude are proposed and validated.The ESA fullpolarimetric interferometry L-band data are used for forest height analysis.The results show that the height is severely underestimated using DEM difference method,In constast,interferometry coherence amplitude method has a overest imation of height.The combined method of DEM difference and interferometry coherence amplitude has a much better estimate,closer to the true height than these two methods.
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Bernhard, Stefan, et Sarah Bernhard. « Do EU Anti-discrimination Provisions Make a Difference ? » Zeitschrift für Soziologie 45, no 1 (1 février 2016) : 57–72. http://dx.doi.org/10.1515/zfsoz-2015-1003.
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Zusammenfassung: Das Diskriminierungsverbot ist zwar ein wichtiger Grundsatz in der Europäischen Union (EU), über seine Auswirkungen innerhalb der Mitgliedsstaaten ist bisher allerdings wenig bekannt. Wir gehen davon aus, dass das Diskriminierungsverbot das Ausmaß von Lohndiskriminierung gegen EU-Ausländer auf den nationalen Arbeitsmärkten in der EU verringert. Diese Vermutung wird mit administrativen Prozessdaten überprüft, indem die Veränderungen von Lohnunterschieden zwischen vollzeitbeschäftigten deutschen und ausländischen Männern auf dem westdeutschen Arbeitsmarkt mit Juhn-Murphy-Pierce-Zerlegungen analysiert werden. Die Ergebnisse stützen die Hypothese: Während die Lohndiskriminierung für die meisten untersuchten Gruppen von EU-Ausländern nach dem Beitritt ihrer Herkunftsländer zurückgegangen ist, lässt sich für die meisten Ausländergruppen aus Drittstaaten gestiegene oder konstante Lohndiskriminierung beobachten. Die europäischen Nichtdiskriminierungsregeln und die mit ihnen verbundenen Übertragungsmechanismen wirken demnach in die intendierte Richtung.
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Fu, C. Y., et J. R. Tsay. « STATISTIC TESTS AIDED MULTI-SOURCE DEM FUSION ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B6 (17 juin 2016) : 227–33. http://dx.doi.org/10.5194/isprs-archives-xli-b6-227-2016.
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Since the land surface has been changing naturally or manually, DEMs have to be updated continually to satisfy applications using the latest DEM at present. However, the cost of wide-area DEM production is too high. DEMs, which cover the same area but have different quality, grid sizes, generation time or production methods, are called as multi-source DEMs. It provides a solution to fuse multi-source DEMs for low cost DEM updating. The coverage of DEM has to be classified according to slope and visibility in advance, because the precisions of DEM grid points in different areas with different slopes and visibilities are not the same. Next, difference DEM (dDEM) is computed by subtracting two DEMs. It is assumed that dDEM, which only contains random error, obeys normal distribution. Therefore, student test is implemented for blunder detection and three kinds of rejected grid points are generated. First kind of rejected grid points is blunder points and has to be eliminated. Another one is the ones in change areas, where the latest data are regarded as their fusion result. Moreover, the DEM grid points of type I error are correct data and have to be reserved for fusion. The experiment result shows that using DEMs with terrain classification can obtain better blunder detection result. A proper setting of significant levels (α) can detect real blunders without creating too many type I errors. Weighting averaging is chosen as DEM fusion algorithm. The priori precisions estimated by our national DEM production guideline are applied to define weights. Fisher’s test is implemented to prove that the priori precisions correspond to the RMSEs of blunder detection result.
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Fu, C. Y., et J. R. Tsay. « STATISTIC TESTS AIDED MULTI-SOURCE DEM FUSION ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B6 (17 juin 2016) : 227–33. http://dx.doi.org/10.5194/isprsarchives-xli-b6-227-2016.
Texte intégralRésumé :
Since the land surface has been changing naturally or manually, DEMs have to be updated continually to satisfy applications using the latest DEM at present. However, the cost of wide-area DEM production is too high. DEMs, which cover the same area but have different quality, grid sizes, generation time or production methods, are called as multi-source DEMs. It provides a solution to fuse multi-source DEMs for low cost DEM updating. The coverage of DEM has to be classified according to slope and visibility in advance, because the precisions of DEM grid points in different areas with different slopes and visibilities are not the same. Next, difference DEM (dDEM) is computed by subtracting two DEMs. It is assumed that dDEM, which only contains random error, obeys normal distribution. Therefore, student test is implemented for blunder detection and three kinds of rejected grid points are generated. First kind of rejected grid points is blunder points and has to be eliminated. Another one is the ones in change areas, where the latest data are regarded as their fusion result. Moreover, the DEM grid points of type I error are correct data and have to be reserved for fusion. The experiment result shows that using DEMs with terrain classification can obtain better blunder detection result. A proper setting of significant levels (α) can detect real blunders without creating too many type I errors. Weighting averaging is chosen as DEM fusion algorithm. The priori precisions estimated by our national DEM production guideline are applied to define weights. Fisher’s test is implemented to prove that the priori precisions correspond to the RMSEs of blunder detection result.
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Borlaf-Mena, Ignacio, Maurizio Santoro, Ludovic Villard, Ovidiu Badea et Mihai Andrei Tanase. « Investigating the Impact of Digital Elevation Models on Sentinel-1 Backscatter and Coherence Observations ». Remote Sensing 12, no 18 (16 septembre 2020) : 3016. http://dx.doi.org/10.3390/rs12183016.
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Spaceborne remote sensing can track ecosystems changes thanks to continuous and systematic coverage at short revisit intervals. Active remote sensing from synthetic aperture radar (SAR) sensors allows day and night imaging as they are not affected by cloud cover and solar illumination and can capture unique information about its targets. However, SAR observations are affected by the coupled effect of viewing geometry and terrain topography. The study aims to assess the impact of global digital elevation models (DEMs) on the normalization of Sentinel-1 backscattered intensity and interferometric coherence. For each DEM, we analyzed the difference between orbit tracks, the difference with results obtained with a high-resolution local DEM, and the impact on land cover classification. Tests were carried out at two sites located in mountainous regions in Romania and Spain using the SRTM (Shuttle Radar Topography Mission, 30 m), AW3D (ALOS (Advanced Land Observation Satellite) World 3D, 30 m), TanDEM-X (12.5, 30, 90 m), and Spain national ALS (aerial laser scanning) based DEM (5 m resolution). The TanDEM-X DEM was the global DEM most suitable for topographic normalization, since it provided the smallest differences between orbital tracks, up to 3.5 dB smaller than with other DEMs for peak landform, and 1.4–1.9 dB for pit and valley landforms.
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Argys, Laura M., et Susan L. Averett. « The effect of family size on education : new evidence from China's one-child policy ». Journal of Demographic Economics 85, no 1 (mars 2019) : 21–42. http://dx.doi.org/10.1017/dem.2018.22.
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AbstractEconomists theorize that the inverse relationship between income and family size reflects a trade-off between child quality and quantity. Testing this hypothesis requires addressing the simultaneity of the quality and quantity decisions. The unanticipated birth of twins and sex composition of the first two children have been used as the exogenous variation in family size with mixed results. We exploit the One-Child Policy (OCP) in China, which exogenously reduced fertility, and examine how the OCP affected the education of Chinese migrants to the USA. Using the American Community Survey and a difference-in-differences strategy, we find higher levels of education for Chinese migrants born after the OCP compared with their counterparts from other East Asian countries. This finding provides additional support for the existence of a quality-quantity trade-off.
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Liu, Zhiheng, Ling Han, Zhaohui Yang, Hongye Cao, Fengcheng Guo, Jianhua Guo et Yiqi Ji. « Evaluating the Vertical Accuracy of DEM Generated from ZiYuan-3 Stereo Images in Understanding the Tectonic Morphology of the Qianhe Basin, China ». Remote Sensing 13, no 6 (22 mars 2021) : 1203. http://dx.doi.org/10.3390/rs13061203.
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Currently available high-resolution digital elevation model (DEM) is not particularly useful to geologists for understanding the long-term changes in fluvial landforms induced by tectonic uplift, although DEMs that are generated from satellite stereo images such as the ZiYuan-3 (ZY3) satellite include characteristics with significant coverage and rapid acquisition. Since an ongoing analysis of fluvial systems is lacking, the ZY3 DEM was generated from block adjustment to describe the mountainous area of the Qianhe Basin that have been induced by tectonic uplift. Moreover, we evaluated the overall elevation difference in ZY3 DEM, Shuttle Radar Topography Mission (1″ × 1″) (SRTM1), and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM) by using the Ice Cloud and Land Elevation Satellite/Geoscience Laser Altimeter (ICESat/GLAH14) point cloud and a DEM of 1:50,000 scale. The values of the root mean square error (RMSE) of the elevation difference for ZY3 DEM were 9.31 and 9.71 m, respectively, and are in good agreement with SRTM1. The river long profiles and terrace heights were also extracted to compare the differences in channel steepness and the incision rates with SRTM1 and ASTER GDEM. Our results prove that ZY3 DEM would be a good alternative to SRTM1 in achieving the 1:50,000 scale for DEM products in China, while ASTER GDEM is unsuitable for extracting river longitudinal profiles. In addition, the northern and southern river incision rates were estimated using the ages and heights of river terraces, demonstrating a range from 0.12–0.45 to 0.10–0.33 m/kyr, respectively. Collectively, these findings suggest that ZY3 DEM is capable of estimating tectonic geomorphological features and has the potential for analyzing the continuous evolutionary response of a landscape to changes in climate and tectonics.
Thèses sur le sujet "DEM of Difference"
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Ryherd, Julia Kay. « QUANTIFYING THE RATES AND SPATIAL DISTRIBUTION OF RECENT SEDIMENTATION WITHIN THE HYDROLOGICALLY CONNECTED FLOODPLAINS OF THE MIDDLE MISSISSIPPI RIVER, USA, USING DIGITAL ELEVATION MODELS AND DENDROGEOMORPHOLOGY ». OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2189.
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The construction of levees along the Mississippi River [MR], beginning in the mid-to-late nineteenth century, have isolated the river along many segments from its floodplain. Sediment from the river is currently deposited in the hydrologically connected floodplain [HCF], the area between the channel margin at low water and the levees. Researchers have studied the amount and rates of sediment deposition along the Upper and Lower Mississippi River segments from the headwaters to Pool 22 and from the Ohio River to the delta; however, no such assessments have been undertaken along the Middle Mississippi River [MMR]. This study attempts to fill the knowledge gap by assessing sedimentation along three islands within the Middle Mississippi River National Wildlife Refuge. On these islands two approaches were undertaken to assess sedimentation along the MMR’s HCF: dendrogeomorphology and the DEM of Difference [DoD] approach. The dendrogeomorphic approach uses tree-ring analyses to document and interpret geomorphic processes and the rates at which they are occurring. The DoD approach subtracts an older DEM from a newer DEM in order to see the change in elevation/depth over time. The geomorphology of the islands and then the entire MMR HCF (from the confluence of the Missouri River to Thebes, IL) were mapped. Using the sedimentation rates for the geomorphic landforms from the three study islands, the sedimentation rates and volumes for the aforementioned portion of the MMR’s HCF were estimated. The estimated volume of sediment was then compared to the MMR’s suspended sediment flux to determine how much of the suspended sediment was going into storage within the MMR’s HCF. The dendrogeomorphic and DoD methods for the study islands yielded average sedimentation rates of 13.3-16.9 mm year-1 and 21.5-80.1 mm year-1, respectively. The rates for the individual landforms on the islands using the dendrogeomorphic results ranged from 5.2 mm year-1 for the splay to 21.8 mm year-1 for the natural levee and splay, with a weighted average of 16.6 mm year-1 for the MMR HCF. Using these rates and the likely range of densities for the floodplain sediments, it is estimated that 4.9-6.6 million metric tons of sediment is accumulating within the MMR annually. This is approximately 5.4-7.4% of the average annual suspended sediment load of the Mississippi River at St. Louis. This means that the MMR is a major sediment sink. If these relatively rapid rates of deposition continue, they have the potential to substantially reduce the HCF’s ability to convey and store flood water which will result in increased flood levels and, consequently, flood risk within the MMR’s levee protected floodplain in the coming decades.
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Rosenberger, Elke. « Asymptotic spectral analysis and tunnelling for a class of difference operators ». Phd thesis, [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=98050368X.
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Rekowsky, Isabel Cristiane. « Variações de área das geleiras da Colômbia e da Venezuela entre 1985 e 2015, com dados de sensoriamento remoto ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/149546.
Texte intégralRésumé :
Nesse estudo foram mapeadas e mensuradas as variações de área, elevação mínima e orientação das geleiras da Colômbia e da Venezuela (trópicos internos), entre os anos 1985-2015. Para o mapeamento das áreas das geleiras foram utilizadas como base imagens Landsat, sensores TM, ETM+ e OLI. Às imagens selecionadas foi aplicado o Normalized Difference Snow Index (NDSI), no qual são utilizadas duas bandas em que o alvo apresenta comportamento espectral oposto ou com características bem distintas: bandas 2 e 5 dos sensores TM e ETM+ e bandas 3 e 6 do sensor OLI. Os dados de elevação e orientação das massas de gelo foram obtidos a partir do Modelo Digital de Elevação SRTM (Shuttle Radar Topography Mission – v03). Em 1985, a soma das áreas das sete geleiras estudadas correspondia a 92,84 km², enquanto no último ano estudado (2015/2016) esse valor passou para 36,97 km². A redução de área ocorreu em todas as geleiras analisadas, com taxas de retração anual variando entre 2,49% a.a. e 8,46% a.a. Houve retração das áreas de gelo localizadas em todos os pontos cardeais considerados, bem como, elevação da altitude nas frentes de geleiras. Além da perda de área ocorrida nas menores altitudes, onde a taxa de ablação é mais elevada, também se observou retração em alguns topos, evidenciado pela ocorrência de altitudes menores nos anos finais do estudo, em comparação com os anos iniciais. Como parte das geleiras colombianas está localizada sobre vulcões ativos, essas áreas sofrem influência tanto de fatores externos, quanto de fatores internos, podendo ocorrer perdas de massa acentuadas causadas por erupção e/ou terremoto.In this study, glaciers located in Colombia and Venezuela (inner tropics) were mapped between 1985-2015. The area of these glaciers was measured and the variations that occurred in each glacier were compared to identify whether the glacier was growing or shrinking. The minimum elevation of the glaciers fronts and the aspect of the glaciers were analyzed. The glaciers areas ware obtained by the use of Landsat images, TM, ETM+ and OLI sensors. The Normalized Difference Snow Index (NDSI) was applied to the selected images, in which two bands were used, where the ice mass has opposite (or very different) spectral behavior: bands 2 and 5 from sensors TM and ETM+, and bands 3 and 6 from sensors OLI. The elevation and the aspect data of the glaciers were obtained from SRTM (Shuttle Radar Topography Mission – v03) Digital Elevation Model. In 1985/1986, the sum of the areas of the seven studied glaciers corresponded to 92.84 km², while in the last year analyzed (2015/2016), this value shrank to 36.97 km². The area shrinkage occurred in all the glaciers that were mapped, with annual decline rates ranging from 2.49%/year to 8.46%/year. It is also possible to observe a decrease of the ice covered in all aspects considered, as well as an elevation in all glaciers fronts. In addition to the area loss occurred at lower altitudes, where the ablation rate is higher than in higher altitudes, shrinkage in some mountain tops was also present, which is evidenced by the occurrence of lower maximum elevations in the final years of the study, when compared with the initial years. Considering that part of the Colombian’s glaciers are located on active volcanoes, these areas are influenced by external and internal factors, and the occurrence of volcanic eruption and/or earthquake can cause sharp mass losses.
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PODESTA', ARIANNA. « L’IMPATTO DEI MEGA-EVENTI SUL WELFARE DI UNA CITTÀ : UN'ANALISI DEL MERCATO IMMOBILIARE APPLICATA AL CASO DELE OLIMPIADI DI TORINO ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2014. http://hdl.handle.net/10280/3678.
Texte intégralRésumé :
In una realtà sempre più globalizzata e di competizione tra città, ospitare un mega-evento è un’opportunità di accelerazione della trasformazione economica, infrastrutturale, sociale e urbana. Questa tesi si propone di valutare se Torino è stata capace di trasformare l’occasione dei Giochi Olimpici Invernali 2006 in una duratura eredità per la città, separando l’effetto dei Giochi in se' e per se' da quello degli investimenti pubblici e della visibilità. Il primo capitolo evidenzia l’importanza di ospitare un evento per l’economia locale e fornisce un quadro generale d’analisi, presentando la scelta della dinamica dei prezzi immobiliari rispetto ad altri metodi usati in letteratura, assieme a quella della tecnica difference-in-differences. Infine, propone il contesto teorico dell’analisi empirica che viene sviluppata nei due capitoli successivi, spiegando le ragioni dietro la scelta del caso delle Olimpiadi di Torino. Il secondo capitolo mira a separare l’effetto differenziale degli investimenti pubblici locali (introducendo una loro nuova misurazione diretta) sull’attrattività della città, distinto da quello dell’ospitare i Giochi di per sé. Il terzo capitolo amplia l’analisi empirica introducendo il ruolo della visibilità internazionale tramite la creazione di un innovativo indice di visibilità basato sui dati forniti dallo strumento Google Trends.In a context of increasing globalisation and competition between cities, hosting mega-events is an opportunity to accelerate economic, infrastructural, social and urban transformation. This dissertation aims at analysing if Turin was able to transform the hosting of the 2006 Winter Olympic Games in a long-lasting legacy for the city, separating the effect of the Olympics per se from the ones of public investments and visibility. In doing so, the first chapter highlights the importance of event hosting for local economies and provides a general framework of analysis, discussing the choice of housing prices dynamics to evaluate the impact of mega events with respect to other methods used in literature, as well as the one of difference-in-differences technique. Finally, the theoretical background of the empirical analysis that follows in the subsequent chapters is presented along with the choice of the case of Turin’s Olympics. The second paper aims at disentangling the differential effect of local public investments (introducing a new direct measure of them) on city appeal, distinguished from that of hosting the Olympics per se. The third paper extends the empirical analysis introducing the role of international visibility in shaping the legacy of Turin Olympics. In doing so, an innovative index of visibility is constructed using data from the Google Trend Tool.
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PODESTA', ARIANNA. « L’IMPATTO DEI MEGA-EVENTI SUL WELFARE DI UNA CITTÀ : UN'ANALISI DEL MERCATO IMMOBILIARE APPLICATA AL CASO DELE OLIMPIADI DI TORINO ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2014. http://hdl.handle.net/10280/3678.
Texte intégralRésumé :
In una realtà sempre più globalizzata e di competizione tra città, ospitare un mega-evento è un’opportunità di accelerazione della trasformazione economica, infrastrutturale, sociale e urbana. Questa tesi si propone di valutare se Torino è stata capace di trasformare l’occasione dei Giochi Olimpici Invernali 2006 in una duratura eredità per la città, separando l’effetto dei Giochi in se' e per se' da quello degli investimenti pubblici e della visibilità. Il primo capitolo evidenzia l’importanza di ospitare un evento per l’economia locale e fornisce un quadro generale d’analisi, presentando la scelta della dinamica dei prezzi immobiliari rispetto ad altri metodi usati in letteratura, assieme a quella della tecnica difference-in-differences. Infine, propone il contesto teorico dell’analisi empirica che viene sviluppata nei due capitoli successivi, spiegando le ragioni dietro la scelta del caso delle Olimpiadi di Torino. Il secondo capitolo mira a separare l’effetto differenziale degli investimenti pubblici locali (introducendo una loro nuova misurazione diretta) sull’attrattività della città, distinto da quello dell’ospitare i Giochi di per sé. Il terzo capitolo amplia l’analisi empirica introducendo il ruolo della visibilità internazionale tramite la creazione di un innovativo indice di visibilità basato sui dati forniti dallo strumento Google Trends.In a context of increasing globalisation and competition between cities, hosting mega-events is an opportunity to accelerate economic, infrastructural, social and urban transformation. This dissertation aims at analysing if Turin was able to transform the hosting of the 2006 Winter Olympic Games in a long-lasting legacy for the city, separating the effect of the Olympics per se from the ones of public investments and visibility. In doing so, the first chapter highlights the importance of event hosting for local economies and provides a general framework of analysis, discussing the choice of housing prices dynamics to evaluate the impact of mega events with respect to other methods used in literature, as well as the one of difference-in-differences technique. Finally, the theoretical background of the empirical analysis that follows in the subsequent chapters is presented along with the choice of the case of Turin’s Olympics. The second paper aims at disentangling the differential effect of local public investments (introducing a new direct measure of them) on city appeal, distinguished from that of hosting the Olympics per se. The third paper extends the empirical analysis introducing the role of international visibility in shaping the legacy of Turin Olympics. In doing so, an innovative index of visibility is constructed using data from the Google Trend Tool.
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Lundberg, Tilda, et Hanne Enoksson. « Flygskatt - Kjempebra eller kan det va ? : En kvantitativ studie om hur individers konsumtion av flygresor påverkas av den norska flygskatten ». Thesis, Uppsala universitet, Nationalekonomiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387888.
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Den första juni 2016 trädde en norsk styckskatt på flygresor i kraft. Avsikten med skatten var både att generera inkomster till statskassan och att minska flygandet hos den norska befolkningen. Denna kvantitativa studie syftar till att utvärdera huruvida den andra avsikten förverkligats. Detta görs genom att undersöka vilken effekt flygstolsavgiften haft på norrmännens flygande. Via en difference-in-differences-estimation med Norge som behandlingsgrupp och Sverige som kontrollgrupp utläses ett signifikant positivt resultat på 0,79 procentenheter när kontrollvariablerna BNP per capita, flygskam och månadsdummies inkluderas. Detta kan tolkas som att skatten har ökat andelen passagerare. Resultatet motsäger ekonomisk teori och tidigare landspecifika utvärderingar av flygskatt. Samtidigt antyder tidigare studier inom området att resultatet kan ha sin grund i att det finns en betalningsvilja för miljöskatter. Däremot finns skäl att vara kritisk mot att sambandet är kausalt eftersom det kan finnas icke-observerade faktorer som påverkar utfallet. I känslighetsanalysen försvinner signifikansen, vilket är ytterligare ett tecken på att flygskatten inte kan förklara den ökning som skett. Huvudresultat är att den norska flygstolsavgiften inte kan bevisas ha minskat andelen passagerare, vilket kan ha sin förklaring i skattens utformning och magnitud. Således är det tvivelaktigt om denna typ av flygskatt kan användas som medel för att minska flygets klimatpåverkan.
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Balaguer, Puig Matilde. « Análisis empírico de soluciones fotogramétricas en estudios de erosión hídrica en laboratorio ». Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/58989.
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[EN] Hydric soil erosion is an economic and ecological problem throughout the world. Current investigation of the processes intervening in the erosion needs detailed information about the soil's surface topography appropriate in resolution and precision for the work's scale. Part of the studies trying to model and quantify the erosive processes are carried out in laboratories, in detailed scales (millimetric), and need methods capable of giving accurate measurements of the surface, in an efficient way. Experiments carried out in a laboratory to measure hydric erosion are based on the use of rain simulators on small soil plots. Soil's rugosity or micro relief influences considerably the distribution of rain water among infiltration and run-off, and is a key factor when modelling erosive processes. Accurate measurement of the plot's relief before and after the rain simulation allows estimation based on the volume differences.
In recent years there is an increasing demand for accurate topographical data in the area of geomorphological science. Reproduction of the soil's surface is done by means of Digital Elevation Models (DEM), generated from massive altimetric data acquired by means of laser scanners or image-based photogrammetric techniques. These data have been collected by means of classical photogrammetric techniques (among others) up until recently; it is not, however, an easy task, and furthermore, to achieve the necessary accuracy, a strict methodology is needed, taking into account all the error sources in the process.
Advances in digital photogrammetry and related fields, such as image processing and computer vision, have brought new software tools with potential application in various fields, such as geomorphology and erosion study. Structure from Motion (SfM) method produces automatically a 3D model of an object from multiple converging images, using automatic image to image registry methods and image correspondence algorithms, which allow a great degree of automatization and a greater ease of use, with a very low cost.
This thesis tries to establish a DEM collection methodology of an experimental zone in a laboratory after repeated episodes of simulated rain by means of photogrammetric techniques based on SfM. Based on the obtained DEM, an estimation of the erosion using DEM of Difference (DoD) techniques will be carried out, comparing these estimations with the results of the obtained run-off and infiltration to validate the method. The results show the suitability of this technique for laboratory erosion studies.[ES] La erosión hídrica del suelo es hoy un problema económico y ecológico en todo el mundo. La investigación actual de los procesos que intervienen en la erosión requiere información detallada sobre la topografía de la superficie del suelo con resolución y precisión adecuadas a la escala de trabajo. Una parte de los estudios que se realizan para la modelización y cuantificación de los procesos erosivos se llevan a cabo en laboratorio, a escalas de detalle (milimétricas), y necesitan métodos capaces de proporcionar mediciones precisas de la superficie, de una manera eficiente. Los experimentos realizados en laboratorio para la medición de la erosión hídrica se basan en el uso de simuladores de lluvia sobre parcelas de suelo de reducidas dimensiones. La rugosidad o microrrelieve del suelo influye considerablemente en el reparto de agua de lluvia entre infiltración y escorrentía, y es un parámetro importante para la modelización de procesos erosivos. La medición precisa del relieve de la parcela antes y después de la simulación de la lluvia permite estimar la erosión a partir de las diferencias de volumen. Así, en los últimos años se ha producido una creciente demanda de datos topográficos de precisión en el ámbito de las ciencias geomorfológicas. La representación de la superficie del suelo se realiza a través de Modelos Digitales de Elevaciones (MDE), generados a partir de datos altimétricos masivos, adquiridos mediante escáneres láser o por técnicas fotogramétricas basadas en imágenes. La obtención de estos datos se ha realizado mediante técnicas fotogramétricas clásicas (entre otras) hasta hace poco; sin embargo, no es una tarea trivial, y además para conseguir las precisiones necesarias se ha de trabajar con una metodología rigurosa que tenga en cuenta todas las fuentes de error en el proceso. Los avances experimentados en fotogrametría digital y otros ámbitos relacionados, como el procesamiento de imágenes y la visión por computador, han proporcionado nuevas herramientas software disponibles con gran potencial de aplicación en muchas y variadas disciplinas, entre ellas la geomorfología y el estudio de la erosión. El método Structure from Motion (SfM) obtiene de forma automática un modelo 3D de un objeto a partir de múltiples imágenes convergentes empleando métodos automáticos de registro imagen a imagen y algoritmos de correspondencia de imágenes, lo que permite un alto nivel de automatización y una mayor facilidad de uso, con un coste muy bajo. En esta tesis se pretende establecer una metodología para la obtención de MDE de una zona experimental en laboratorio tras sucesivos episodios de simulación de lluvia mediante técnicas fotogramétricas basadas en SfM. A partir de los MDE obtenidos se realizará una estimación de la erosión aplicando técnicas de diferencias de MDE (DoD), contrastando estas estimaciones con los resultados de los sedimentos arrastrados por la escorrentía y la infiltración para validar el método. Los resultados han demostrado la idoneidad de esta técnica en los estudios de erosión en laboratorio.
[CAT] L'erosió hídrica del sòl és actualment un problema econòmic i ecològic en tot el món. La investigació actual dels processos que intervenen en l'erosió requereix informació detallada sobre la topografia de la superfície del sòl amb resolució i precisió adequades a l'escala de treball. Una part dels estudis que es realitzen per a la modelització i quantificació dels processos erosius es duen a terme en laboratori, a escales de detall (mil·limètriques) , i necessiten mètodes capaços de proporcionar mesuraments precisos de la superfície, d'una manera eficient. Els experiments realitzats en laboratori per al mesurament de l'erosió hídrica es basen en l'ús de simuladors de pluja sobre parcel·les de sòl de reduïdes dimensions. La rugositat o microrrelleu del sòl influeix considerablement en el repartiment d'aigua de pluja entre infiltració i escolament, i és un paràmetre important per a la modelització de processos erosius. La medició precisa del relleu de la parcel·la abans i després de la simulació de la pluja permet estimar l'erosió a partir de les diferències de volum. Així, en els últims anys s'ha produït una creixent demanda de dades topogràfiques de precisió en l'àmbit de les ciències geomorfològiques. La representació de la superfície del sòl es realitza a través de Models Digitals d'Elevacions (MDE) , generats a partir de dades altimètriques massives, adquirides per mitjà d'escàners làser o per tècniques fotogramètriques basades en imatges. La obtenció d'estes dades s'ha realitzat amb tècniques fotogramètriques clàssiques (entre altres) fins fa poc; no obstant això, no és una tasca trivial, i a més per a aconseguir les precisions necessàries s'ha de treballar amb una metodologia rigorosa que tinga en compte totes les fonts d'error en el procés. Els avanços experimentats en fotogrametria digital i altres àmbits relacionats, com el processament d'imatges i la visió per computador, han proporcionat noves ferramentes disponibles amb gran potencial d'aplicació en moltes i variades disciplines, entre elles la geomorfologia i l'estudi de l'erosió. El mètode Structure from Motion (SfM) obté de forma automàtica un model 3D d'un objecte a partir de múltiples imatges convergents emprant mètodes automàtics de registre imatge a imatge i algoritmes de correspondència d'imatges, la qual cosa permet un alt nivell d'automatització i una major facilitat d'ús, amb un cost molt baix. En esta tesi es pretén establir una metodologia per a l'obtenció de MDE d'una zona experimental en laboratori després de successius episodis de simulació de pluja per mitjà de tècniques fotogramètriques basades en SfM. A partir dels MDE obtinguts es realitzarà una estimació de l'erosió aplicant tècniques de diferències de MDE (DoD) , contrastant estes estimacions amb els resultats dels sediments arrossegats per l'escolament i la infiltració per a validar el mètode. Els resultats han demostrat la idoneïtat d'esta tècnica en els estudis d'erosió en laboratori.
Balaguer Puig, M. (2015). Análisis empírico de soluciones fotogramétricas en estudios de erosión hídrica en laboratorio [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/58989
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Stenbeck, Kelly, et Daniel Törnqvist. « EXPANSION AV KOLLEKTIVTRAFIKEN – ÄR DET VÄRT PENGARNA ? : En studie av bostadspriser och den planlagda tunnelbanan i Stockholm ». Thesis, Uppsala universitet, Nationalekonomiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387788.
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Stockholms län har upplevt en stark demografisk tillväxt det senaste decenniet, vilket har medfört behov av nya investeringar i kollektivtrafiken och i bostäder. I denna uppsats studeras sambandet mellan närhet till den nya planerade tunnelbanan i Stockholm och bostadsrättspriser. Baserat på egeninsamlade paneldata om bostadsrättsförsäljningar i Barkarby och Nacka strand perioden 2013–2017 skattas en hedonisk prismodell för att se hur euklidiskt avstånd till närmsta planerade tunnelbaneentré samvarierar med bostadsrättspriser. Vidare undersöks om besluten om stationslokalisering i Barkarby och Nacka har haft en positiv effekt på bostadspriser, genom att jämföra skillnader i priser före och efter beslut om nya tunnelbanestationer. Resultaten visar att sambandet mellan närhet till den planerade tunnelbanan och bostadsrättspriser skiljer sig beroende på område. Priser på bostadsrätter stiger med minskat avstånd till närmsta planerade tunnelbaneentré i Barkarby medan de sjunker i Nacka strand. Det återfinns ingen statistiskt säkerställd effekt av besluten om stationslokalisering på bostadsrättspriser.
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Emery, Russell N. « Refining and Expanding the Feature Stamping Process ». Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd1004.pdf.
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GAZZAROLI, DILETTA. « Culture della differenza e diversity management nelle organizzazioni : una sfida già raccolta ? » Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/32573.
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Nel campo della psicologia delle organizzazioni, la gestione della differenza è un argomento di crescente interesse. Studi sul Diversity Managemetn sono stati promossi dalla graduale consapevolezza che per le organizzazioni, promuovere la diversità non solo contribuisce a garantire la soddisfazione e le prestazioni dei singoli lavoratori, ma offre anche vantaggi in termini di business e riconoscimento da stakeholders esterni e contesto sociale. Podsiadlowski et al (2012) hanno identificato cinque culture – Reinforcing Homogeneity, Color-Blind, Fairness, Access, Integration – con cui le organizzazioni possono approcciare la differenza e che possono essere collocate su un continuum da difensiva, a reattiva, a proattiva. Scopo di questo lavoro è ottenere una fotografia delle culture organizzative della differenza nel contesto italiano al fine di comprendere "lo stato dell'arte". Inoltre, si mira a capire: se e che tipo di interazioni la cultura organizzativa della differenza può avere con altri fattori della vita organizzativa e che tipo di impatto la cultura organizzativa della differenza può avere sulla creatività organizzativa e sul benessere individuale. Al fine di offrire un contributo alla validazione di due strumenti non ancora particolarmente diffusi in ambito italiano si sono anche testate le proprietà psicometriche della Cultural Intelligence Scale e del Diversity Perspective Questionnaire.In the field of organizational psychology, Diversity Management is a topic of growing interest. Studies on Diversity Management have been led by the gradual awareness that for organizations, fostering diversity not only helps to ensure the satisfaction and performance of the individual workers, but also offers benefits in terms of business and recognition from external stakeholders and social context. Podsiadlowski et al. (2012) identified five different ways organizations approach diversity – Reinforcing Homogeneity, Color-Blind, Fairness, Access, Integration – that can be seen on a continuum from defensive, to reactive, to proactive attitude. Aim of this work is taking a picture of the organisational cultures of difference in the Italian context in order to understand "the state of the art". Moreover, this work aims to understand: if and what kind of interactions the organisational cultures of difference can have with other organizational life factors and what kind of impact the organisational cultures of difference can have on organizational creativity and individual well-being. In order to offer a contribution to the validation of two tools not yet particularly widespread in terms of use in the Italian context we also tested the psychometric properties of: the Cultural Intelligence Scale and the Diversity Perspective Questionnaire.
Livres sur le sujet "DEM of Difference"
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Gabriella, Schubert, et Dahmen Wolfgang, dir. Bilder vom Eigenen und Fremden aus dem Donau-Balkan-Raum : Analysen literarischer und anderer Texte. München : Südosteuropa-Gesellschaft, 2003.
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Institut für Sozialpädagogische Forschung Mainz., dir. Differenz und Differenzen : Zur Auseinandersetzung mit dem Eigenen und dem Fremden im Kontext von Macht und Rassismus bei Frauen. Bielefeld : K. Böllert, KT-Verlag, 1994.
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Landis, Beth. Making a difference. Reno, Nev. (P.O. Box 19081, Reno 89511) : Michael Sion, 2002.
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comp, Larrosa Jorge, et Pérez de Lara, Nuria, comp., dir. Imágenes del otro. Barcelona : Virus Editorial, 1997.
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Wege aus dem stummen Spiegel : Versuch einer Phänomenologie der Geschlechterdifferenz. Frankfurt am Main : Verlag J. Knecht, 2000.
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Un mondo del tutto differente : La storia di Wow e dei Verdena. Castel Gandolfo (Rm) [i.e. Rome, Italy] : Arcana, 2012.
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Identità e differenze nell'architettura del Mediterraneo. Roma : Gangemi, 2006.
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Bono, Paola. Esercizi di differenza : Letture partigiane del mondo e dei suoi testi. Ancona : Costa & Nolan, 1999.
Trouver le texte intégralChapitres de livres sur le sujet "DEM of Difference"
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Hochstätter, Ulrica. « Das Opfer : Begriff, Viktimisierungsfolgen und -bewältigung ». Dans Die Fragen der Opfer im Strafprozess, 5–18. Wiesbaden : Springer Fachmedien Wiesbaden, 2023. http://dx.doi.org/10.1007/978-3-658-40530-4_2.
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ZusammenfassungDie Viktimologie (abgeleitet von lat. victima = Opfer) ist die Lehre vom Verbrechensopfer: Sie beschäftigt sich mit dem Opfer-Werden und dem Opfer-Sein. Diese Lehre ist ein Teilgebiet der Kriminologie und eine interdisziplinäre Wissenschaft, deren zentrale Fächer die Rechtswissenschaft, die Soziologie, die Psychologie und die Psychotraumatologie darstellen. Die systematische wissenschaftliche Beschäftigung mit dem Opfer begann etwa Mitte des vergangenen Jahrhunderts vor dem Hintergrund des nationalsozialistischen Völkermords, dem Holocaust. Die sozialwissenschaftliche kriminologische und viktimologische Forschung entstammt traditionell dem englischsprachigen Raum und prägt zudem die hiesige Forschung. Seit dem Aufkommen der Viktimologie wird Kriminalität aus differenten Blickrichtungen, im „Dreiklang von Tat, Täter und Opfer“, erforscht. Inhaltlich setzt sich die Viktimologie mit den Erscheinungsformen, Ursachen und Folgen von Opferwerdungsprozessen auseinander und thematisiert Fragen der Intervention und Prävention.
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Deuber-Mankowsky, Astrid, et Christoph F. E. Holzhey. « Blurb ». Dans Situiertes Wissen und regionale Epistemologie, 289. Wien : Turia + Kant, 2013. http://dx.doi.org/10.37050/ci-07_001.
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Wie wird das Leben zum Objekt des Wissens? Und wie gestaltet sich das Verhältnis von Leben, Wissenschaft und Technik? Donna J. Haraway und Georges Canguilhem verstehen diese Fragen als politische Fragen und Epistemologie als eine politische Praxis. Die besondere Aktualität von Canguilhems Denken leitet sich aus der von ihm gestellten Frage her, wie sich eine Geschichte der Rationalität des Wissens vom Leben schreiben lässt. Niemand hat die politische Intention dieser Frage besser verstanden als Foucault, der in Canguilhems Nachfolge den Menschen als Lebewesen und dessen Geschichte als Teil der Geschichte der Rationalisierung des Lebens problematisierte. Haraway bezieht sich nicht explizit auf Canguilhem, schließt jedoch in ihrer Auseinandersetzung mit der amerikanischen feministischen Wissenschaftskritik, der Actor-Netzwerk-Theorie, der Philosophie des Pragmatismus und Whiteheads relationistischen Philosophie an die von ihm gestellte Frage an. In dem vorliegenden Band diskutieren namhafte PhilosophInnen, EpistemologInnen und MedienwissenschaftlerInnen aus Frankreich, Belgien und Deutschland offenliegende und verborgene Bezüge, Relationen und Differenzen zwischen dem Konzept des „situierten Wissens“ Haraways und der „regionalen Epistemologie“ Canguilhems. Es ist eine Diskussion, die zugleich interdisziplinär und international ist und damit in doppelter Weise versucht, dem Anspruch der Situiertheit und der Regionalität des Wissens gerecht zu werden.
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Werner, Micha H. « Ist Moral nur kluger Egoismus ? Ansätze des Kontraktualismus ». Dans Einführung in die Ethik, 65–89. Stuttgart : J.B. Metzler, 2020. http://dx.doi.org/10.1007/978-3-476-05293-3_3.
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ZusammenfassungKlassischer Naturalismus: Die systematischen Überlegungen des vorangehenden Kapitels haben sich mit dem inhaltlichen Ertrag der antiken Tugendethik beschäftigt (siehe Kap. 10.1007/978-3-476-05293-3_2). Hinterfragen lässt sich jedoch auch deren Begründungsbasis: Was ist der Maßstab, an dem sich unsere Urteile über das gute Leben und das gerechte Zusammenleben in letzter Hinsicht orientieren sollen, und wie wird dieser Maßstab begründet? Hinsichtlich dieser Frage erscheinen die Differenzen zwischen den dominierenden Strömungen antiker und scholastischer Tugendethik und Naturrechtslehre aus heutiger Sicht weniger gravierend als die Gemeinsamkeiten. Dass das naturgemäße Leben auch das gute und richtige Leben sei, ist zwischen den philosophischen Schulen der Antike nicht strittig.
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Cede, Franz, et Gerhard Mangott. « Die Außenpolitik gegenüber Russland ». Dans Handbuch Außenpolitik Österreichs, 555–77. Wiesbaden : Springer Fachmedien Wiesbaden, 2022. http://dx.doi.org/10.1007/978-3-658-37274-3_26.
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ZusammenfassungDer Artikel schildert die Entwicklung der Beziehungen zwischen Österreich und der Russländischen Föderation. Kontroversen über die Frage, ob Russland als Fortsetzerstaat der Union der Sozialistischen Sowjetrepubliken (UdSSR) anzuerkennen sei und Differenzen über den Beitrittsantrag Österreichs an die Europäische Gemeinschaft (EG)/Europäische Union (EU) prägten den Beginn des Untersuchungszeitraums. Seitdem sind die Beziehungen weitgehend unbelastet, der wirtschaftliche und kulturelle Austausch sehr eng. In den letzten Jahren hat Österreich eine sehr aktive Russlandpolitik mit intensiver Besuchsdiplomatie verfolgt – mit dem Ziel, eine „Brückenfunktion“ zwischen der EU und Russland einzunehmen. Das aber war illusionär. Rechtsstaatlichkeit, Menschen- und Bürgerrechte und die repressive Verhärtung der Lage in Russland sind im bilateralen Dialog nahezu völlig ausgespart geblieben.
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Müller-Seeger, Julia. « Mikrofundierung von Vermittlungs- und Übersetzungsprozessen in Co-Working Spaces als neue Arbeitsform der Sharing Economy ». Dans Differenz - Übersetzung - Teilhabe, 163–78. Bielefeld, Germany : transcript Verlag, 2023. http://dx.doi.org/10.14361/9783839464809-008.
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Dieser Beitrag widmet sich der Mikrofundierung von Teilhabemöglichkeiten in der Sharing Economy am Beispiel von Co-Working Spaces. Die Mikrofundierung ist ein Ansatz des Strategischen Managements in der Betriebswirtschaftslehre, der den Fokus auf die Individual-Ebene, konkret auf die Interaktion von Mitgliedern einer Organisation(seinheit) legt. Dadurch sollen Makro-Phänomene, wie z.B. Marktführerschaft, Gewinnerzielung oder Kundenzufriedenheit, durch die Mikro-Ebene erklärt werden. Auf der Mikro-Ebene hat sich als neue Arbeitsform das Arbeiten im Co-Working Space herauskristallisiert. Co-Working Spaces sind Einrichtungen, die Büroinfrastruktur zur Verfügung stellen. Diese kann von Nutzern für eine bestimmte Zeit gemietet werden. Gleichzeitig bieten Co-Working Spaces aber auch Begegnungsflächen, sodass Nutzer verschiedener Unternehmen (z.B. Start-ups oder Freelancer) miteinander interagieren können. Manche Co-Working Konzepte integrieren auch gemeinsam Events und Workshops, um den (in)formellen Austausch der Co-Worker zu ermöglichen. Dadurch verschwimmen traditionelle Unternehmensgrenzen, die sich bisher auch räumlich voneinander abgegrenzt haben (z.B. durch eigene Gebäude). Ob diese neue Arbeitsform Teilhabe ermöglicht, soll mit Hilfe des Mikro-Makro-Modells von Will und Müller (2020) (2019) rekonstruiert werden. Dazu wird die Mikro-Ebene mit ihren Interaktionen zwischen Individuen genauer betrachtet und das Ziel der Teilhabe auf der Makro-Ebene rekonstruiert. Es zeigt sich, dass die zugrundeliegende Denkweise der Trennung zwischen Mikro- und Makro-Ebene bzw. der intendierten und nicht-intendierten Konsequenzen für diese spezielle Form der Zusammenarbeit überdacht werden sollte.
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Sun, Huinan, et Zhuoqing Zhang. « Discussion on the Difference of the Grain Particle Parameters in Reality and DEM ». Dans Springer Proceedings in Physics, 177–82. Singapore : Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-1926-5_20.
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Lewis, Alison. « The Stasi, the Confession and Performing Difference : Brigitte Burmeister’s Unter dem Namen Norma ». Dans German Writers and the Politics of Culture, 155–72. London : Palgrave Macmillan UK, 2003. http://dx.doi.org/10.1057/9781403938756_10.
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Haus, Juliane. « Going native und coming home – Ein Ausblick ». Dans Wissen, Kommunikation und Gesellschaft, 375–77. Wiesbaden : Springer Fachmedien Wiesbaden, 2021. http://dx.doi.org/10.1007/978-3-658-33019-4_6.
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ZusammenfassungDie vorliegende Untersuchung ist das Resultat der Auseinandersetzung einer qualitativen Forscherin mit dem Feld der wirtschaftswissenschaftlichen Laborexperimente. Die Inspiration zu neuen Forschungsarbeiten entstammt nicht selten aus dem Gefühl der Befremdung und der Differenz zwischen der beobachteten und der eigenen Wissenschaftskultur der Forschenden. So regte mich die Auseinandersetzung mit dem wissenschaftlichen Verfahren des Experiments zu einer kritischen Reflexion der Frage an, welche Potenziale ein experimentelles Vorgehen für die qualitative soziologische Forschung besitzen könnte. Das abschließende Kapitel skizziert kurz , welche Anstöße die Erkenntnisse dieser Arbeit für die Methodologie der Soziologie selbst bieten und plädiert für eine konstruktive Auseinandersetzung mit dem Potential verschiedener Spielarten experimenteller Forschungsdesigns in der qualitativen sozialwissenschaftlichen Forschung.
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Beck, Laura. « Dazwischen : Ich ». Dans Interkulturalität. Studien zu Sprache, Literatur und Gesellschaft, 123–42. Bielefeld, Germany : transcript Verlag, 2022. http://dx.doi.org/10.14361/9783839460887-007.
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Laura Beck widmet sich in diesem Beitrag der Verhandlung von Alteritäts- und Adoleszenzerfahrungen in Julya Rabinowichs Jugendroman »Dazwischen: Ich« (2016), in dem diese ein ganzes Panorama an ,Alteritäten' auffächere. Die Migrationserfahrung der jugendlichen Ich-Erzählerin sei nicht nur durch ,kulturelle Differenz', sondern ebenfalls durch eine Vielzahl an miteinander verschränkten körperlichen, psychischen, sprachlichen und räumlichen Grenzüberschreitungen bedingt. Diese würden u.a. durch Rückgriff auf Raummetaphern und literarische Intertexte ausgestaltet. Der Beitrag zeigt, wie »Dazwischen: Ich« gegen eine Vorstellung von ,Identitäten' arbeitet, die sich nur in Abhängigkeit von monolithischen Kulturkonzepten herausbilden. Beck stellt jedoch auch heraus, dass die Fokussierung des Textes auf ,Überkulturelles' Gefahr läuft, Widerständiges an den Rand zu drängen.
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Stock, Robert, et Jan Müggenburg. « Assistenz für wen ? » Dans Autonome Autos, 339–58. Bielefeld, Germany : transcript Verlag, 2021. http://dx.doi.org/10.14361/9783839450246-012.
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Der Beitrag von Robert Stock und Jan Müggenburg historisiert Konzepte und Praktiken assistierter PKW-Mobilität. Der Text befasst sich mit Techniken des Autofahrens, der Einpassung von Körpern in die Fahrkabine sowie dem Verhältnis von körperlicher Differenz und der Entwicklung spezifischer Assistenzsysteme. Betrachtet werden behindertengerecht umgebaute Fahrzeuge mit eingebautem Rollstuhllift, PKW-fahrende Menschen mit Behinderung und ihre Vorstellungen automobiler Freiheit angesichts nicht-barrierefreier ÖPNV sowie blinde Fahrer:innen im Kontext autonomer Fahrzeuge. Die Autoren argumentieren, dass Mobilitätsgerechtigkeit in Zeiten autonomer Fahrzeuge nur unter der Berücksichtigung körperlicher Variabilität und gesellschaftlicher Heterogenität möglich sein wird.
Actes de conférences sur le sujet "DEM of Difference"
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Wang, Lei, Jun Chen, Hongwei Zhang et Lijun Chen. « Difference Analysis of SRTM C-Band DEM and ASTER GDEM for Global Land Cover Mapping ». Dans 2011 International Symposium on Image and Data Fusion (ISIDF). IEEE, 2011. http://dx.doi.org/10.1109/isidf.2011.6024257.
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Haneberg, William C., et Sarah Johnson. « DOUBLE GAUSSIAN FILTERING TO SUPPRESS NOISE AND IMPROVE IDENTIFICATION OF NEW LANDSLIDES ON DEM DIFFERENCE MAPS ». Dans GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-305313.
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Ishii, Shuto, Isami Suto, Hiroaki Tabe, Keisuke Nagato, Moju Zhao, Yoshifumi Ueshige, Takashi Iritani et Masayuki Nakao. « Construction of a Soil Clods Recognition Bench-Scale Experiment for Discrete Element Method Modeling of Tilling Phenomena ». Dans 11th Asia-Pacific Regional Conference of the ISTVS. International Society for Terrain-Vehicle Systems, 2022. http://dx.doi.org/10.56884/vbxy3767.
Texte intégralRésumé :
The development of rotary claws in tiller machines has been evaluated using actual equipment and analysis based on the discrete element method (DEM), which is an effective method for modeling the movement of granular materials. The required functions of the rotary claw are to break the soil into small pieces and plow the soil flat. However, evaluation by testing using actual equipment is difficult for precise measurements, and a considerable amount of time is required for one test. Additionally, DEM simulations have difficulty reproducing the soil behavior owing to the large number of parameters that determine their accuracy. Therefore, a comparison with the experimental results is necessary when determining DEM parameters. This research aims to develop a soil clod recognition method and an evaluation system for evaluating tractor performance. The evaluation system was designed to measure the soil shape before and after tilling with a 1/4-scale tillage claw. To capture the changes in the soil shape and distribution and size of the soil clods, we developed an image processing method. This method uses pointcloud data obtained from a depth camera to calculate the difference before and after tilling. The experimental parameters were the soil moisture content and claw rotation speed. Their effects on the formation and decomposition of the soil clods were evaluated. To confirm the feasibility of the results obtained from the proposed evaluation system, DEM simulations were performed under identical conditions to compare the distribution and size of the soil clods and changes in soil shape. The experimental results showed that the location, number, and size of scattered soil clods varied with the moisture content of the soil, and rotational speed of the claw. Based on the experimental results, a comparison was made with the results of the DEM analysis to clarify the differences between the two. The developed model experiment system for soil clods and the image processing method made it possible to quantitatively compare soil dispersal between the experiment and the DEM, which may accelerate the search for parameters for the DEM to reproduce the tilling.
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Yang, Yancheng, et Haixiao Liu. « Coupled Discrete Element-Finite Difference Method Simulations of OMNI-Max Anchor Installation in Granular Seabed ». Dans ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18452.
Texte intégralRésumé :
Abstract The ocean resources development is becoming increasingly urgent as the depletion of land reserves combine to enhance demand. In some of the deep-water areas, terrigenous deposits are found near landmasses, which are formed from material eroded from the land surface. They are constituted of clay, silt, sand, and granular soil. More and more gravity installed anchors (GIA) are employed as a part of the offshore foundation systems in these deep-water areas. A kind of newly developed GIA, called OMNI-Max anchor, with a mooring arm located near the anchor tip that is free to rotate about the anchor length, are an effective approach for mooring marine devices to the ocean floor. While providing the reaction force, these anchors can maintain the stability of offshore facilities. The ability of the anchor to achieve these duties relies on its keying and diving behaviors after penetration. Both shallow and deep penetrations, including offshore foundations and anchors penetrations, in granular media are what long interests geotechnical and geophysical fields. The final penetration depth of GIA in the granular seabed is also influenced by quite a few factors, such as impact velocity, particle size distribution (PSD) and anchor surface friction. However, this kind of large-strain problem is not agreeable to typical continuum numerical methods. In the current work, we propose that the coupled discrete element method (DEM) and finite difference method (FDM) is a more proper and efficient tool to investigate the penetration of OMNI-Max anchors in granular soil. The effects of the factors mentioned above are considered in the coupled DEM-FDM simulations. The relative ultimate penetration depths for different penetration conditions are presented and quantified. The response of granular material during penetration is applied to provide insight into system response at the microscale. Energy dissipation in the assembly by both friction and collision at the particle scale is considered. Results show that anchor penetration depth grows with rising impact velocity, while it decreases with an increase of anchor surface friction. When the ratio of fluke width and median diameter of granular size is smaller than 5.6, even under a relatively loose state, the application of OMNI-Max anchor is not recommended because of difficulty in assuring the required penetration depth (about 1.3 anchor lengths, 11.90 m). Although, at the similar impact velocity, the GIA tip embedment in sand is quite shallower than that in clay, alternative GIA designs may realize higher penetrations in the sand, and prove to be viable anchoring solution for granular seabed sediments. Finally, the fabric characters after penetrations are presented to analyze and reveal the state of soil experienced drastic disturbance. The characteristics of these distributions tend to particular states depending on the relative position to the anchor, which have a significant influence on subsequent behaviors of OMNI-Max anchor during the keying process.
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Menezes, Chelsea, et Cameron J. Turner. « Implementing a Discrete Element Method for Fused Deposition Modeling Additive Manufacturing Thermal Modeling ». Dans ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-71947.
Texte intégralRésumé :
Abstract One of the challenges of additively manufactured parts is that additive manufacturing processes can lead to anisotropic material properties. For this research, we focus on fused deposition modeling (FDM) which is a common consumer grade process that also is often used for early prototyping due to its low investment and processing cost. In FDM, a semimolten filament is extruded. Within the filament (the intrafilament bonds), the material properties are essentially that of a bulk material that has been injection molded. However, because of the differences in temperature when adjacent filaments are deposited, the material properties between filaments within a layer (the intralayer bonds) are generally less than that of the intrafilament bonds leading to an anisotropic behavior within a layer. Similarly, the temperature difference between layers leads to yet another different material bonding strength (interlayer) that is also less than that of the intralayer or intrafilament bonds. Our hypothesis is that these anisotropic property differences can be predicted using Discrete Element Models (DEM) to model the process of printing the part filament by filament and layer by layer and the subsequent cooling process. A DEM approach discretizes the filament into discrete elements that are treated as a lumped parameter elements connected to adjacent elements through a set of heat transfer boundary conditions. Elements with external part surfaces are therefore connected to the external environment, or in the case of elements in the base layer of the part, are connected to the print bed which is often heated to encourage bonding between filaments. The DEM model is validated by comparing the predictions of the model against observed behaviors in FDM printing. For instance, the exposed surfaces of an FDM print will cool faster than elements in the core of the print, or elements that are in contact with the heated printing bed. This paper describes the process of developing a thermal DEM model in MatLAB, including the assumptions underlying the element level heat transfer model. In addition, discussion of the model results is included to demonstrate the validity of the model as well as the comparisons made to available simulation and experimental data which allows us to validate the underlying behavior of the model. As a result of this research, there are several avenues available for future work including the estimation of bond strength between fibers and layers, the incorporation of viscosity effects, mechanical loading, and the possibilities for process optimization based on intelligent filament path planning, reheating technologies and adaptively controlling the build plate and environmental temperatures.
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Higashida, Kyohei, Teppei Yamada, Takuya Tsuji et Toshitsugu Tanaka. « A Numerical Model for the Motion of Large Non-Spherical Object in Fluidized Bed ». Dans ASME/JSME/KSME 2015 Joint Fluids Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/ajkfluids2015-32744.
Texte intégralRésumé :
In practical application of fluidized beds, large solids coexist with small solids. Tsuji et al. (AIChE J., 60(5), pp. 1606–1620, 2014) proposed a numerical model which expresses the behavior of flows including dense solid objects with large size difference based on the DEM-CFD coupling method. In the present study, the model is extended to represent the non-sphericity of large objects by adding a multi-sphere model. Firstly, we perform validation study in a mm-size bubbling fluidized bed and confirm qualitative agreements between the numerical model and the experiment. After that, sinking and floating motion of a large non-spherical object in a fluidized bed are numerically investigated in detail.
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Sun, Jin, et Francine Battaglia. « Analysis of Solid Structures and Stresses in a Gas Fluidized Bed ». Dans ASME/JSME 2007 5th Joint Fluids Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/fedsm2007-37189.
Texte intégralRésumé :
Structures and stresses for the solid phase in a gas-solid fluidized bed are analyzed using results from hybrid simulations. The hybrid method couples the discrete element method (DEM) for particle dynamics with the averaged two-fluid (TF) equations for the gas phase. The coupling between the two phases is modeled using an interphase momentum transfer term. Structure information is characterized using force network size distribution, which shows no large force network existing in the fluidized bed. The normal contact forces have an exponentially decaying distribution. Solid phase continuum fields (local volume fraction, strain rate, stress tensor, and granular temperature) are computed using a coarse-graining process. The results show that the stress has difference in normal stress components. The collisional contribution is larger than the kinetic contribution and spatially correlated to force networks. Stresses are also computed using a kinetic theory stress model. It is demonstrated that the kinetic theory model predicts no difference in normal stress components and larger normal stresses than those computed from the coarse-graining process.
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Mart, Steven R., Stephen T. McClain et Lesley M. Wright. « Turbulent Convection From Deterministic Roughness Distributions With Varying Thermal Conductivities ». Dans ASME 2011 Turbo Expo : Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45146.
Texte intégralRésumé :
Many flows of engineering interest are bounded by surfaces that exhibit roughness with thermal conductivities much lower than common metals and alloys. Depending on the local roughness element convection coefficients, the low thermal conductivities of the roughness elements may create situations where temperature changes along the heights of the elements are important and must be considered in predicting the overall surface convection coefficient. The discrete-element model (DEM) for flows over rough surfaces was recently adapted to include the effects of internal conduction along the heights of ordered roughness elements. While the adapted DEM provided encouraging agreement with the available data, more data are required to validate the model. To further investigate the effects of roughness element thermal conductivity on convective heat transfer and to acquire more experimental data for DEM validation, four wind tunnel test plates were made. The test plates were constructed using Plexiglas and Mylar film with a gold deposition layer creating a constant flux boundary condition with steady state wind tunnel measurements. The four test plates were constructed with hexagonal distributions of hemispheres or cones made of either aluminum or ABS plastic. The plates with hemispherical elements had element diameters of 9.53 mm and a spacing-to-diameter ratio of 2.099. The plates with conical elements had base element diameters of 9.53 mm and a spacing-to-base-diameter ratio of 1.574. An infrared camera was used to measure the temperature of the heated plates in the Baylor Subsonic Wind Tunnel for free stream velocities ranging from 2.5 m/s to 35 m/s (resulting in Reynolds number values ranging from 90,000 to 1,400,000 based on the distance from the knife-edge to the center of the infrared camera image) in turbulent flow. At lower Reynolds numbers, the thermal conductivity of the roughness elements is a primary factor in determining the heat transfer enhancement of roughness distributions. At the higher Reynolds numbers investigated, the hemispherical distribution, which contained more sparsely spaced elements, did not exhibit a statistically significant difference in enhancement for the different thermal conductivity elements used. The results of the study indicate that the packing density of the elements and the enhancement on the floor of the roughness distribution compete with the roughness element thermal conductivity in determining the overall convection enhancement of rough surfaces.
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Fang, X., et J. Tang. « Analysis of Segregation Phenomenon in Granular Motion ». Dans ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14443.
Texte intégralRésumé :
Over the past decade, many studies have been carried out to investigate one of the unique phenomena in granular materials: vibration-induced segregation in granular mixture, i.e., under vertical vibration, larger granules rise to the top even without density difference with other granules. However, the mechanisms behind this phenomenon are not yet completely understood. In this study, the discrete element method (DEM) is used for the numerical analysis of the granular segregation in a vertically vibrating container. We systematically investigate the rising time of an intruder inside the granular mixture as a function of the granular size, density, depth, and the vibrating frequency and amplitude. Our studies show that the segregation phenomenon is caused by a variety of mechanisms within different vibration regimes. Under weak vibration, segregation is driven by the geometrical effect and inertia. Under moderate vibration, segregation can be enhanced dramatically with the occurrence of convection. Under strong vibration where the granular material becomes fluidized, the buoyancy or sinkage of granules prevails and segregation may be suppressed.
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Kiracofe, Daniel, Matthew Postell, Onome Scott-Emuakpor, Brian Runyon et Tommy George. « Discrete Element Method Simulations of Additively Manufactured Components With Integrated Particle Dampers ». Dans ASME Turbo Expo 2021 : Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/gt2021-58462.
Texte intégralRésumé :
Abstract One major benefit of Additive Manufacturing is parts counts reduction. Several formerly distinct parts can be printed as one unit, reducing cost and weight. However, the interface between parts is often a major source of vibration damping, so eliminating interfaces can lead to fatigue failures. To alleviate this, researchers have been exploring the integration of damping features inside parts. Leaving a small pocket of unfused powder creates a particle damper. Particle dampers have long been known to suppress unwanted vibration. However they are highly complex and predicting their behavior is difficult. The particle damper literature often has contradictory claims, as what works best for one application does not work for another. Because the additive feedstock powder is much smaller (5–50 μm) than particles in typical particle dampers, it is difficult to draw conclusions from the existing literature to develop design guidelines. This papers reports on a Discrete Element Method (DEM) numerical simulation of additively manufactured cantilever beams with a small pocket of unfused powder. DEM explicitly simulates the motion of each particle and their interactions. Previously reported experiments with varying beam geometry showed nearly an order of magnitude difference in damping ratio depending on the location of the pocket along the beam. The simulation was able to accurately predict the damping ratio based on the input geometry. As a result, the correlated simulation tool can be used to optimize future designs. From the simulations, it was observed that particle-wall momentum exchange and particle-particle inelastic collisions appeared to be key contributors to the damping ratio. Additionally, a non-linear subharmonic motion of particles was observed, which suggests additional ways to improve performance.
Rapports d'organisations sur le sujet "DEM of Difference"
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Blundell, S. User guide : the DEM Breakline and Differencing Analysis Tool—gridded elevation model analysis with a convenient graphical user interface. Engineer Research and Development Center (U.S.), août 2022. http://dx.doi.org/10.21079/11681/45040.
Texte intégralRésumé :
Gridded elevation models of the earth’s surface derived from airborne lidar data or other sources can provide qualitative and quantitative information about the terrain and its surface features through analysis of the local spatial variation in elevation. The DEM Breakline and Differencing Analysis Tool was developed to extract and display micro-terrain features and vegetative cover based on the numerical modeling of elevation discontinuities or breaklines (breaks-in-slope), slope, terrain ruggedness, local surface optima, and the local elevation difference between first surface and bare earth input models. Using numerical algorithms developed in-house at the U.S. Army Engineer Research and Development Center, Geospatial Research Laboratory, various parameters are calculated for each cell in the model matrix in an initial processing phase. The results are combined and thresholded by the user in different ways for display and analysis. A graphical user interface provides control of input models, processing, and display as color-mapped overlays. Output displays can be saved as images, and the overlay data can be saved as raster layers for input into geographic information systems for further analysis.
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Mason, H., C. Colla, S. Matt et L. Dinh. Solid state NMR Investigation of Structural Differences in Pelletized DEB Samples. Office of Scientific and Technical Information (OSTI), janvier 2022. http://dx.doi.org/10.2172/1860808.
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English, M., S. Schexnayder, J. Altman et M. Schweitzer. Making a difference : Ten case studies of DSM/IRP interactive efforts and related advocacy group activities. Office of Scientific and Technical Information (OSTI), mars 1994. http://dx.doi.org/10.2172/10160467.
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Ahn, T., A. Charnes et W. W. Cooper. A Note on the Efficiency Characterizations Obtained in Different DEA (data Envelopment Analysis) Models. Fort Belvoir, VA : Defense Technical Information Center, juin 1988. http://dx.doi.org/10.21236/ada201343.
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Reed, David M. DPEM (Depot Purchased Equipment Maintenance)Versus DMIF (Depot Maintenance Industrial Fund) : What's the Difference and Why Should We Care ? Fort Belvoir, VA : Defense Technical Information Center, mai 1988. http://dx.doi.org/10.21236/ada202640.
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Fiedler, Björn. Report on demo mission and dissemination pathways of obtained data based on different observational platforms. EuroSea, 2022. http://dx.doi.org/10.3289/eurosea_d7.1.
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Wibowo, Johannes, et Jamie López-Soto. Field Jet Erosion Tests on Benbrook Dam, Texas. Engineer Research and Development Center (U.S.), décembre 2021. http://dx.doi.org/10.21079/11681/42545.
Texte intégralRésumé :
This report summarizes the results of eight field Jet Erosion Tests (JETs) performed on Benbrook Dam, TX. The results from these tests will be used by the U.S. Army Corps of Engineers, Fort Worth District, in assessments of the erosion resistance of the Benbrook Dam with regards to possible overtopping by extreme flooding. The JETs were performed at four different locations, i.e., two locations at the lowest crest elevation and two locations at the mid-slope face of the downstream embankment. Variations in estimated critical hydraulic shear stress and erosion rate values may have been caused by differences in soil composition, i.e., when the material changed from silt/sand to clay. The resulting values of the Erodibility Coefficient, Kd, and Critical Stress, τc, are very useful information in assessing the stability of Benbrook Dam during an overtopping event. Because of the observed natural variability of the materials, combining the erosion parameters presented in this report with the drilling logs and local geology will be imperative for assessing erosion-related failure modes of Benbrook Dam.
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Tan, Peng, et Nicholas Sitar. Parallel Level-Set DEM (LS-DEM) Development and Application to the Study of Deformation and Flow of Granular Media. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, mars 2023. http://dx.doi.org/10.55461/kmiz5819.
Texte intégralRésumé :
We present a systematic investigation of computational approaches to the modeling of granular materials. Granular materials are ubiquitous in everyday life and in a variety of engineering and industrial applications. Despite the apparent simplicity of the laws governing particle-scale interactions, predicting the continuum mechanical response of granular materials still poses extraordinary challenges. This is largely due to the complex history dependence resulting from continuous rearrangement of the microstructure of granular material, as well as the mechanical interlocking due to grain morphology and surface roughness. X-Ray Computed Tomography (XRCT) is used to characterize the grain morphology and the fabric of the granular media, naturally deposited sand in this study. The Level-Set based Discrete Element Method (LS-DEM) is then used to bridge the granular behavior gap between the micro and macro scale. The LS-DEM establishes a one-to-one correspondence between granular objects and numerical avatars and captures the details of grain morphology and surface roughness. However, the high-fidelity representation significantly increases the demands on computational resources. To this end a parallel version of LS-DEM is introduced to significantly decrease the computational demands. The code employs a binning algorithm, which reduces the search complexity of contact detection from O(n2) to O(n), and a domain decomposition strategy is used to elicit parallel computing in a memory- and communication-efficient manner. The parallel implementation shows good scalability and efficiency. High fidelity LS avatars obtained from XRCT images of naturally deposited sand are then used to replicate the results of triaxial tests using the new, parallel LS-DEM code. The result show that both micro- and macro-mechanical behavior of natural material is well captured and is consistent with experimental data, confirming experimental observation that the primary source of peak strength of sand is the mechanical interlocking between irregularly shaped grains. Specifically, triaxial test simulations with a flexible membrane produce a very good match to experimentally observed relationships between deviatoric stress and mobilized friction angle for naturally deposited sand. We then explore the viability of modeling dynamic problems with a new formulation of an impulse based LS-DEM. The new formulation is stable, fast, and energy conservative. However, it can be numerically stiff when the assembly has substantial mass differences between particles. We also demonstrate the feasibility of modeling deformable structures in the rigid body framework and propose several enhancements to improve the convergence of collision resolution, including a hybrid time integration scheme to separately handle at rest contacts and dynamic collisions. Finally, we extend the impulse-based LS-DEM to include arbitrarily shaped topographic surfaces and exploit its algorithmic advantages to demonstrate the feasibility of modeling realistic behavior of granular flows. The novel formulation significantly improves performance of dynamic simulations by allowing larger time steps, which is advantageous for observing the full development of physical phenomena such as rock avalanches, which we present as an illustrative example.
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Toutin, T. Comparison of stereo-extracted DTM from different high-resolution sensors : SPOT-5, EROS-A, IKONOS-II, and QuickBird. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2004. http://dx.doi.org/10.4095/220073.
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Schwedes, Christian. Präventionsarbeit an Schulen in Deutschland : Handlungsfelder und räumliche Implikationen. Goethe-Universität, Institut für Humangeographie, mars 2010. http://dx.doi.org/10.21248/gups.7576.
Texte intégralRésumé :
Die hier vorgestellte Studie wurde durch eine konstruktivistisch informierte Betrachtung kontrastiert, um dadurch sowohl das methodische Vorgehen der quantitativen Empirie als auch deren Ergebnisse zu reflektieren. Abschließend sollen diese beiden Aspekte noch einmal aufgegriffen werden. Bezüglich der empirischen Methodik macht sie offensichtlich, dass die quantitative Studie eine Reifikation eingeschränkter Raumbilder darstellt. Sie reproduziert eine Denkweise, die komplexe soziale Prozesse anhand vereinfachter Faktoren nachvollziehbar zu machen versucht. Bei der Einbeziehung der Raumstrukturtypisierung des BBR in die Auswertung zeigt sich eine begrenzte Aussagereichweite von räumlichen Strukturdaten bezüglich (sub-)lokaler und regionaler Analysen. Die komplexen sozialräumlichen Bedingungen schulischer Präventionsarbeit, so das Ergebnis, entziehen sich weitgehend einer Analyse mithilfe von Geodaten, die entweder aus mehreren Einzelkomponenten aggregiert sind (im Falle der Raumstrukturtypen20, Bevölkerungsdichtewerte und Zentrenerreichbarkeit) oder relativ große räumliche Einheiten umfassen (z. B. siedlungsstrukturelle Gebietstypen21). Eine differenzierte Sicht auf spezifisch urbane oder rurale Settings schulischer Präventionsarbeit können die (bisher) zur Verfügung stehenden räumlichen Daten nicht leisten. Darüber hinaus wäre es selbst bei Verfügbarkeit räumlicher Daten in größerer Detailschärfe unmöglich, eine kontingente soziale Wirklichkeit vor Ort mit Hilfe sozialstatistischer Raumdaten adäquat abzubilden. Als zum Teil sehr aussagekräftig im Sinne des quantitativen Forschungsparadigmas ergaben sich hingegen die Einschätzungen der Befragten bezüglich ihres räumlichen Umfeldes. Aus Sicht eines konstruktivistisch informierten Forschungsverständnisses geben aber auch diese Ergebnisse nur eine ganz spezifische Form einer durch den quantitativen Forschungsprozess geprägten Wahrheit wieder. Trotz dieser erkenntnistheoretischen Einschränkungen können die Ergebnisse der Umfrage zur Präventionsarbeit an Schulen Anlass für weiterführende Diskussionen sein und als Basis für eine kritische Reflektion dienen. Im Folgenden werden daher die zentralen Punkte der Diskussion der empirischen Ergebnisse noch einmal aufgenommen und zusammengeführt. Pädagogen an Schulen in Deutschland sehen sich in sehr unterschiedlichem Maße mit Herausforderungen konfrontiert. Die Verschiedenheit der Bedingungen des schulischen Alltags ist vor allem geprägt durch die hohe Selektivität und die darin zugrundeliegende Ausdifferenzierung des deutschen Schulsystems. Wie bei anderen schulischen Belangen auch liegen die Differenzen bezüglich der Herausforderungen, die sich den Schulen stellen, und der Ausgestaltung von Präventionsarbeit zumeist zwischen den Schulformen. Die Aussagen der Pädagog/-innen deuten dabei auf den Einfluss sehr unterschiedlicher sozialer Wirklichkeiten auf den Schulalltag hin. Aus Sicht der Schulleiter/-innen ballen sich Herausforderungen, insbesondere was die Thematisierung abweichenden Verhaltens von Schüler/-innen angeht, vor allem an Förder- und Hauptschulen. In städtischen Quartieren, die aus Sicht der Befragten durch soziale Problemlagen gekennzeichnet sind, konzentrieren sich die Probleme in Schulen zusätzlich. Präventionsarbeit an Schulen versteht sich häufig als Antwort auf problematische soziale Verhältnisse. Da sich insgesamt ein sehr positives Bild bezüglich der von Schüler/-innen erlernten sozialen Fähigkeiten ergibt und andere Studien auf einen Rückgang beispielsweise der Jugendgewalt hindeuten, muss davon ausgegangen werden, dass es andere Gründe für die Konjunktur von schulischer Präventionsarbeit gibt als zunehmend aggressives Verhalten unter Kindern und Jugendlichen. Die Ergebnisse der Untersuchung belegen auch, dass Präventionsarbeit unabhängig von der Problemwahrnehmung an Schulen zur – oder nicht zur – Anwendung kommt. So spielt die Problemwahrnehmung beispielsweise keine Rolle für die Schwerpunktsetzung bei ihrer Finanzierung. Der verstärkte Einsatz von Geldern in Städten und vor allem dort, wo das Umfeld der Schulen für „multikulturell“ oder „sozial schwach“ gehalten wird, macht einen kulturalistischen bzw. sozialökologischen Einschlag von Präventionsarbeit an Schulen offensichtlich. Eine eingeschränkte Problemorientierung wird ebenfalls durch die Ergebnisse bezüglich der Prävention politisch motivierter (Hass-)Kriminalität deutlich. Fremdenfeindlichkeit im Schulumfeld wird zwar wahrgenommen, in vielen Fällen jedoch folgen darauf keine Präventionsaktivitäten. Auf der einen Seite reagiert schulische Präventionsarbeit gar nicht auf offensichtliche Missstände, auf der anderen Seite wird Prävention eingesetzt, obwohl kaum Probleme thematisiert werden (vgl. z. B. Gewaltprävention an Gymnasien). Im Wesen des Präventionsgedankens liegt begründet, dass sich Präventionsarbeit nicht unbedingt an den Herausforderungen des schulischen Alltags orientiert. Selbst wenn keine konkreten Probleme vorliegen, ist im Sinne von Primärprävention vorbeugendes Handeln angezeigt. So kommt es auch dazu, dass Präventionsarbeit häufig die Durchführung allgemeiner Lebenskompetenzprogramme bedeutet. Die Vielzahl sehr allgemein auf die Aneignung von Sozialkompetenzen ausgerichteter Präventionscurricula macht deutlich, wie der Präventionsgedanke/- diskurs den Schulalltag auch in Bereichen durchdringt, die vormals von anderen Diskursen beeinflusst waren. Unter dem Begriff „Prävention“ wird heute explizit vermittelt, was in früheren Jahrzehnten als „Erziehung“ en passant von den Lehrer/-innen geleistet wurde. Mit dem Erstarken des Präventionsparadigmas hat sich der Umgang der Lehrer/-innen mit ihren Schüler/-innen verändert. Das Fördern sozialer Fähigkeiten findet stärker institutionalisiert statt und erhält, das ist ein entscheidender Machteffekt (im Sinne Foucaults (1978)) des Präventionsbegriffs, mit der neuen Bezeichnung auch eine neue Konnotation. Sie ist verknüpft mit Begriffen wie „Risiko“, „Gefährdung“ oder „Sicherheit“. Schon die Vermittlung grundlegender sozialer Kompetenzen wird, durch den Präventionsgedanken geprägt, zunehmend von dem defizitorientierten Ziel geleitet, abweichendes Verhalten zukünftig zu verhindern oder zu minimieren. Gerade an Grundschulen, die nach den Ergebnissen der Umfrage die wichtigsten Sozialisationsinstanzen unter den Schulen sind, ist der Aspekt der frühen Förderung von Sozialkompetenzen bei Kindern Ausgangspunkt für die zunehmende Durchdringung mit dem Präventionsgedanken. Der Präventionsdiskurs, so zeigen die Ergebnisse der Umfrage, besitzt die Macht, Eingriffe in das schulische Miteinander von Lehrer/-innen und Schüler/-innen zu legitimieren, die ohne seine Popularität kaum denkbar wären. Geht man davon aus, dass unter der Bedingung „individualisierter Lebenslagen“ (Beck 2003: 144) und einer damit Einhergehenden Pluralisierung von Lebensweisen Grenzerfahrungen ein wesentliches Element von Sozialisation und Identitätsbildung sind, kommt abweichendem Verhalten eine große Bedeutung im Prozess des Aufwachsens zu. Schädlich für die Gesellschaft, im Sinne einer Verstetigung in Form kriminellen Verhaltens, ist es in den seltensten Fällen. Aus dieser Sicht erfordert nicht jedes abweichende Verhalten ein präventives Entgegenwirken und es müsste ein besonderes Augenmerk darauf liegen, dass der Präventionsgedanke nicht unreflektiert als Legitimationsfolie für ordnungspolitische Eingriffe instrumentalisiert wird. Ob der verdachtsgeleitete Umgang mit Kindern wünschenswert ist, bleibt fraglich. Bezweifelt werden kann, dass die Notwendigerweise mit Prävention einhergehende Defizitorientierung lustvolles Lernen befördert.