Die Kosten-Wirksamkeitsanalyse als methodischer Ansatz zur Bewertung alternativer Schulnetze. Bericht über eine Simulationsstudie

Die durch den dramatischen Geburtenrückgang in den neuen Bundesländern erzwungene Reorganisation des Schulsystems in den kommenden Jahren kann zu gravierenden Ineffizienzen führen, wenn die Implikationen schulorganisatorischer Lösungsansätze nicht ausreichend bedacht werden. In dem Projekt „Anwendung von Optimierungsverfahren im Rahmen der Schulnetzplanung" versuchen wir deshalb, über ein Simulationsmodell und eine ex-ante Evaluation mittels einer Kosten-Wirksamkeitsanalyse, die finanziellen, pädagogischen und regionalpolitischen Auswirkungen unterschiedlicher Planungsansätze simultan zu erfassen. Untersuchungsregion ist das Bundesland Mecklenburg-Vorpommern. Durch das Forschungsvorhaben wird Systemwissen für eine prioritätengeleitete Ressourcenallokation zur Verfügung gestellt, auf das angesichts der Steuerungsprobleme im Bildungssystem, die sich durch rückläufige Schülerzahlen und die öffentliche Finanzknappheit sowie durch die Komplexität der Entscheidungssituationen ergeben, nicht verzichtet werden kann. (DIPF/Orig.)The renewed re-organization of the school system to be undertaken in the next few years, necessitated by the dramatic decline in the birthrate in the new Laender, may lead to severe inefficiencies if the implications of school. Organizational solutions are not adequately taken into account. In the project "Application of optimization procedures within the framework of school network planning", we therefore try to simultaneously register the financial, pedagogical, and regional-political consequences of different planning approaches through a simulation model and an ex-ante evaluation by means of a cost-effectiveness analysis. Mecklenburg-Vorpommern was chosen as site of the investigation. The research project provides systemic knowledge for a priority-guided allocation of resources we cannot do without in view of the problems connected with managing the educational system, - problems that are caused by the decline in the number of students, by the shortage of public funds as well as by the complexity of the situations in which decisions have to be taken. (DIPF/Orig.

Fracture geometry and statistics of Ceres’ floor fractures

Floor-fractured craters are one of the most distinct features on Ceres. Most of the fractures are located on the crater floors. The floor-fractures are concentric, radial or polygonal and share similarities with the floor-fractured craters (FCC) of Class 1 and 4 on the Moon (e.g., Buczkowski et al., 2018; Schultz, 1976) In total we measured 2336 fractures in thirteen craters. We analyzed their width, length, orientation and density. Floor-fractures on Ceres do not show a global uniform sense of orientation. Nevertheless, two or more preferred orientations can be found in nearly every crater. The density map illustrates that there is typically no decrease of fracturing from the crater center to the crater rim and denotes formation mechanisms that are not necessarily impact driven. Because of the variation in these parameters, it is more likely that FFC on Ceres are globally independent and show different formation mechanisms. The geometry of the floor-fractures suggests an inhomogeneous, brittle surface material, in some cases with volatile components. We also propose that the formation mechanisms on Ceres are comparable to those on the Moon and Mars and such mechanisms include cooling/melting processes, degassing, and subsidence of the crater floor by up-doming of subsurface material as a result of absolute tensile stresses

Characteristics of Polygonal Craters on (1) Ceres

The Dawn spacecraft arrived at Ceres in March 2015. There, the on-board Framing Camera (FC) collects image data with a resolution of up to 35 m/pixel, which reveal a large variety of impact crater morphologies including polygonal craters. Polygonal craters show straight rim sections aligned to form an angular shape. They are com- monly associated with fractures in the target material, which may be preserved as linear structures on Ceres [3, 4]. On Ceres, we find polygonal craters with a size ranging between 5 km and 280 km in diameter. However, the ma- jority of polygonal craters have diameters ranging between 10 km and 50 km diameter. A preferential hexagonal shape is observed and some polygonal craters exhibit central peaks or relaxed crater floors. On average there are eight to ten polygonal craters per 100,000 km 2 , however the northern latitudes have a slightly higher and the southern latitudes a slightly lower polygonal crater density. This may hint at an older and younger age of the northern (> 60°N) and southern regions (> 60°S) compared to the mid latitudes, respectively. Alter- natively, the relaxation of craters may be advanced in the mid latitudes which are generally warmer than the poles and thus support the relaxation of depressions. Also, the southern region harbors relatively large craters which may have altered or destroyed preexisting structures in the crust which are necessary for the formation of polygonal craters. Most polygonal craters have six or seven straight rim sections; however, there is a tendency for fewer edges with decreasing crater size. Although this observation may be biased due to the map resolution, it is also possible that the impactor creating a relatively small polygonal crater embeds less energy and thus forms the straight rim sections during the excavation stage. This may result in fewer straight rim sections compared to more energetic impactors which form their polygonal shape during the modification stage. Straight rim sections and edges of polygonal craters often align with linear features associated with Ceres’ tec- tonics. Small and medium-sized polygonal crater rims tend to align with the general direction of linear features, whereas very large polygonal crater edges tend to be intersected by the linear features. This may hint at the differ- ent formation processes of polygonal craters depending on the embedded energy. In contrast, polygonal craters are also present in areas with no obvious tectonic features. These polygonal craters may be produced by subresolution or subsurface fractures. [3] Buczkowski, D. et al., GSA 2015, 1-4 November 2015, Baltimore, MD, USA, #282-8, 2015 [4] von der Gathen, I. et al., GSA 2015, 1-4 November 2015, Baltimore, MD, USA, #282-9, 201

Morphologie von Einschlagskratern und die Verteilung von Auswurfmaterial auf dem Zwergplaneten Ceres

The following thesis describes a combined approach of geologic mapping and ballistic calculations of ejected material to investigate the surface composition and the processes that shaped the dwarf planet Ceres. The analyses are based on data of the Dawn mission. After orbiting the asteroid Vesta from 2011 to 2012, the Dawn spacecraft reached Ceres’ orbit in March 2015. The main goals of the Dawn mission were to investigate the geology, interior composition and past and present endogenic and exogenic processes of Ceres and Vesta to describe their evolution and to gain a broader understanding of the early solar system and protoplanet growth (Russell and Raymond, 2011; Russell et al., 2016). This thesis will contribute to the understanding of the geology, the evolution and the dynamics of Ceres. This work utilized a two step procedure to analyze the composition and geologic history of the surface of Ceres. First, including clear filter, topographic and color data, geologic mapping was conducted for the Sintana quadrangle in the southern hemisphere of Ceres to identify geologic processes and to help to assemble a global stratigraphy for Ceres. In the course of the mapping, geologic units and features were analyzed and absolute ages of geologic units were determined. Second, ejecta deposition of the small and fast rotating dwarf planet was investigated by analytical ballistic calculations in order to understand the origin and distribution of geologic units. To examine the relation between ejecta and secondary cratering, particle sizes were calculated. Moreover, the special case of ejecta dynamics of boulder craters was analyzed, as well as the ballistics and size frequency distributions of the ejecta blocks themselves. The geologic mapping reveals an ice rich subsurface that is predominantly resurfaced by large impact events. The crater shapes in the Sintana quadrangle resemble those on icy satellites with a great variety of morphologies. Moreover, secondary crater chains cross the quadrangle. In addition, the morphology of blocky landslides is indicative of an ice rich subsurface. The mapping region shows no evidence of endogenic activity, but the absolute age of the cratered terrain background unit hints to a resurfacing event that was possibly induced by impact ejecta/melt of the close by Kerwan basin. Features and processes that were identified in the Sintana region, such as secondary crater chains, boulders, resurfacing by large impact craters and asymmetric ejecta blankets, are even more distinct in other regions of Ceres. Ballistic calculations were used to investigate the origin of those observations. The results of the ballistic calculations show that the rotation of Ceres leads to a specifically asymmetric ejecta deposition and that a planet wide contamination with secondary craters that bias surface ages is very likely. The low gravity regime results in a long range transport of particles; hence ejecta might be deposited far away from its primary crater. The particle sizes of high velocity particles could be large enough to produce distant secondary craters and can therefore explain the secondary crater chains that are observed all over Ceres. The analysis of boulder crater ejecta deposits shows that they are as asymmetric as the ejecta deposits of larger impact basins on Ceres. The investigation of boulders demonstrates that the deposition of low velocity ejecta is also influenced by the Coriolis effect. Steep slopes of boulder size frequency distributions are in agreement with the idea that such blocks produce secondary craters with a similar distribution (McEwen and Bierhaus, 2006). As already revealed by geologic mapping, the ballistic analysis confirms that a high contamination of the surface by secondary impacts is likely, for instance, in the shape of non radial crater chains. Secondary craters, in turn, pose problems in the dating of geological units, because they can increase the estimated age of a surface. In short, this work is the first extensive study about the rotational effects on ejecta deposition on the dwarf planet Ceres

Grid-mapping Hellas Planitia, Mars – Insights into distribution, evolution and geomorphology of (peri)-glacial, fluvial and lacustrine landforms in Mars' deepest basin

• Grid mapping provides valuable datasets for geographic and geostatistical analyses. • Gap of latitude-dependent mantle in NE Hellas probably caused by wind currents. • Scalloped terrain is controlled by solar insolation and aeolian activities. • Viscous-flow features and gullies are scarce at low elevations. • Even at high-resolution mapping, no clear shoreline morphologies have been discovere