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To improve the quality of algorithms for automatic generation of Digital Surface Models (DSM) from optical stereo data in the remote sensing community, the Working Group 4 of Commission I: Geometric and Radiometric Modeling of Optical Airborne and Spaceborne Sensors provides on its website http://www2.isprs.org/commissions/comm1/wg4/benchmark-test.html a benchmark dataset for measuring and comparing the accuracy of dense stereo algorithms. The data provided consists of several optical spaceborne stereo images together with ground truth data produced by aerial laser scanning. In this paper we present our latest work on this benchmark, based upon previous work. As a first point, we noticed that providing the abovementioned test data as geo-referenced satellite images together with their corresponding RPC camera model seems too high a burden for being used widely by other researchers, as a considerable effort still has to be made to integrate the test datas camera model into the researchers local stereo reconstruction framework. To bypass this problem, we now also provide additional rectified input images, which enable stereo algorithms to work out of the box without the need for implementing special camera models. Care was taken to minimize the errors resulting from the rectification transformation and the involved image resampling. We further improved the robustness of the evaluation method against errors in the orientation of the satellite images (with respect to the LiDAR ground truth). To this end we implemented a point cloud alignment of the DSM and the LiDAR reference points using an Iterative Closest Point (ICP) algorithm and an estimation of the best fitting transformation. This way, we concentrate on the errors from the stereo reconstruction and make sure that the result is not biased by errors in the absolute orientation of the satellite images. The evaluation of the stereo algorithms is done by triangulating the resulting (filled) DSMs and computing for each LiDAR point the nearest Euclidean distance to the DSM surface. We implemented an adaptive triangulation method minimizing the second order derivative of the surface in a local neighborhood, which captures the real surface more accurate than a fixed triangulation. As a further advantage, using our point-to-surface evaluation, we are also able to evaluate non-uniformly sampled DSMs or triangulated 3D models in general. The latter is for example needed when evaluating building extraction and data reduction algorithms. As practical example we compare results from three different matching methods applied to the data available within the benchmark data sets. These results are analyzed using the above mentioned methodology and show advantages and disadvantages of the different methods, also depending on the land cover classes.

The Second Workshop on Benchmark Problems for Airframe Noise Computations, BANC-II, was held on 7-8 June 2012 in Colorado Springs, CO, USA. The objective of this workshop was to assess the present computational capability in the area of physics-based prediction of dierent types of airframe noise problems and to advance the state-of-the-art via a combined effort. This paper summarizes the results from workshop category 1 which focuses on the prediction of broadband turbulent boundary-layer trailing-edge noise and related source quantities. 2D airfoil sections, namely a NACA0012 and DU-96-180, served as test cases. Code-to-code comparisons in this category were mainly restricted to relatively fast RANS-based methods applying statistical noise theory. Overall, the prediction capability was sufficient to capture the principal trailing-edge farfield noise scaling behavior in the mid-frequency range (about 1 kHz

Straipsnyje, remiantis tekstais, publikuotais mėnraštyje „Ostdeutsche Monatshefte“, analizuojama Kuršių nerija kaip Rytų Prūsijos kraštovaizdžio ikona. Žurnalas buvo leidžiamas Dancige 1920 - 1939 m. redaktoriaus ir leidėjo Carlo Langės. Šis periodinis leidinys buvo pateiktas kaip „kovos už vokiškuosius rytus“ gynėjas, siekiant parodyti „vokišką“ gamtą ir kultūrą teritorijose, kurios buvo prarastos po Pirmojo pasaulinio karo, ir tuo stiprinti šių teritorijų ir visos Vokietijos bendruomenės tarpusavio priklausomumo jausmą. „Ostdeutsche Monatshefte“ skelbė daugybę straipsnių apie „vokiškųjų rytų“ kraštovaizdžio išskirtinumą, ir Kuršių nerija buvo viena iš šio kraštovaizdžio ikonų. Išeities tašku straipsnyje laikomas kraštovaizdžio apibrėžimas, kurį „nukalė“ vokiečių mokslininkas Hansjakobas Kūsteris, apibūdinęs šį reiškinį kaip „viską, ką žmogus suvokia savojoje aplinkoje ir ką įkomponuoja į tam tikras sąryšius“. Kraštovaizdžio elementais laikomi tiek gamtos (jūros, kalnai, upės, flora ir pan.), tiek ir kultūros (miestai, gyvenvietės, keliai, gatvės) reiškiniai. Atrinktų tekstų susijusių su Kuršių nerija, analizė rodo, kad ypatingą kraštovaizdžio „atmosferą“ turėjo išryškinti gausybė elementų. Tarp jų minėtinos kopos, jūra, įlanka ir paukščių pasaulis. Briedis, kuris buvo nuolatinis kiekvieno Kuršių nerijos aprašymo elementas, tapo tam tikra praeities laikų dvasios simboliu. Galiausiai paveikslas būdavo baigiamas minint Kuršių nerijos gyventojus (kuršininkus), kovojančius su gamtos atšiaurumu. Kuršių nerijos kraštovaizdis buvo perteikiamas kaip kupinas kontrastų, kadangi jame koegzistavo nepastovumas ir stabilumas, grožis ir šlykštumas, gyvenimas ir mirtis. Šią Kuršių nerijos kraštovaizdžio „dvasią“ geriausiai išreiškė dažnai vartota dykumos metafora „Kuršių nerija kaip Europos Sachara“. Daugelis analizuotų tekstų pasižymėjo neutraliu kraštovaizdžio aprašymu. Kuršių nerija būdavo pateikiama kaip išskirtinai vokiškas kraštovaizdis tuose tekstuose, kurių tematika būdavo susijusi su Rytų Prūsijai kildavusiomis grėsmėmis ir kuriais siekta perteikti patrauklius kraštovaizdžio elementus Vokietijos Reicho gyventojams. 1939 metai, kai Klaipėdos kraštas buvo „atgautas“ Reicho, šiuo požiūriu yra lūžio momentas. Tekstuose, kurie tuomet pasirodė „Ostdeutsche Monatshefte“, buvo išryškinama „dvidešimties metų kova už Vokietijos kultūrą“. The paper deals with the Curonian Spit as an East Prussian landscape icon by using the texts that appeared in the "Ostdeutsche Monatshefte" monthly as its source. The magazine was published in Danzig in the years 1920-1939 by Carl Lange, who was its publisher and editor-in-chief. The magazine strived to "fight for the German East", or to show the German nature and culture of the land lost by the Reich after World War I and to strengthen the sense of belonging of its inhabitants to the entire German cultural community. The Ostdeutsche Monatshefte published numerous articles about the peculiarities of the Eastern German landscape. The Curonian Spit was one of such landscape icons. The starting point is a definition of landscape coined by the German scientist Hansjakob Küster, who defines this phenomenon as "everything that man perceives in his surroundings and what he combines into a certain relation". Elements of landscape include both items of nature (seas, mountains, rivers, flora, etc.), and also elements of culture (towns, villages, roads, and streets, etc.). The analysis of the selected texts devoted to the Curonian Spit shows a number of elements that make up the peculiar "mood" of the landscape. They include: dunes, the sea, the bay, and the world of birds. The moose is a permanent element of each of the descriptions of the Curonian Spit that grows to become a symbol of the spirit of bygone times. Finally, the picture is completed with the inhabitants of the Curonian Spit (Curonians) who fight against the adversities of nature. The landscape of the Curonian Spit is perceived as full of contrasts. It is characterised by the coexistence of changeability and stability, beauty and ugliness, life and death. That "mood" of the Curonian Spit's landscape is best evoked in the frequently used metaphor of a desert (the Curonian Spit as the "Sahara of Europe"). The majority of the texts reviewed a The majority of the texts reviewed are characterised by neutral descriptions of the landscape. The Curonian Spit is perceived as a specifically German landscape especially in those texts, the topic of which deals with the threats posed for East Prussia and the purpose of which is to present that element of landscape to other inhabitants of the Reich. The year 1939 marks a breakthrough there and the "recapture" of the Klaipeda Region (Memelland) by the Reich. Texts that were then published in the Ostdeutsche Monatshefte explicitly mention the "twenty-year long struggle for German culture".

Investment decisions of cooperative banks are very restricted to their risk capacity. A well defined and organised Risk Management Process supports those investment activities and assists to achieve a balanced situation between risk and return. Several ways can be chosen to allocate risk capital. The aim of this allocation is on the one hand to reduce risk as much as necessary to keep in line with self defined risk limits but on the other hand to get the highest possible return under those conditions. In this paper we first of all analyse and identify several risks in a cooperative bank and then quantify and measure for example interest rate risk with a non parametric Value-at-Risk-approach. Secondly we define risk capacity limits and then use a passive strategy to allocate the available risk capital.