Der "Dropstein-Laminit" von Bögerhof und seine Zuordnung zu den Drenthe-zeitlichen Ablagerungen des Wesertals bei Rinteln

Die vorliegende Untersuchung befaßt sich mit eiszeitlichen Ablagerungen im Raum der TK Rinteln. Ein "Ton"-Vorkommen wurde als drenthezeitlicher Dropstein- Laminit angesprochen. Dieser liegt stratigraphisch unter den Krankenhagen-Möllenbecker-Kieskörpern und wurde als geringfügig jünger als der Hauptvorstoß der Drenthe-Vereisung in diesem Raum eingestuft. Für die oben erwähnten Kieskörper wurde eine Entstehung als Endmoränen ausgeschlossen. Sie wurden als Kame-Terrassen gedeutet

Mengenbestimmung der jungen Abtragungsprodukte des Thüringer Waldes am Beispiel des Weser-Fluß-Systems

Es wird der Versuch unternommen, auf der Basis von Geröllanalysen die Menge der Abtragungsprodukte des Thüringer Waldes im Weser-Fluß-System zu bestimmen. Die errechnete Menge wird in Bezug gesetzt zu der Größe des Abtragungsgebietes. Daraus ergibt sich, daß innerhalb der letzten 200 000 Jahre mindestens eine Schicht von 50 m Mächtigkeit abgetragen worden sein muß. Um die Höhe des Gebirges unverändert zu belassen, müsste eine junge Hebung von 1/4 mm pro Jahr angenommen werden. Solche Vorgaben sollten zu einer kritischen Diskussion Anlaß geben.researc

Assessment of Buffet Forcing Function Development Process Using Unsteady Pressure Sensitive Paint

A wind tunnel test was conducted at the Ames Unitary Plan Wind Tunnel to characterize the transonic buffet environment of a generic launch vehicle forebody. The test examined a highly instrumented version of the Coe and Nute Model 11 test article first tested in the 1960s. One of the measurement techniques used during this test was unsteady pressure sensitive paint (uPSP) developed at the Arnold Engineering Development Complex. This optical measurement technique measured fluctuating pressures at over 300,000 locations on the surface of the model. The high spatial density of these measurements provided an opportunity to examine in depth the assumptions underpinning the development of buffet forcing functions (BFFs) used in the development of the Space Launch System vehicle. The comparison of discrete-measurement-based BFFs to BFFs developed by continuous surface pressure integration indicates that the current BFF development approach under predicts low frequency content of the BFFs while over predicting high frequency content. Coherence-based adjustments employed to reduce over prediction in the surface integration of discrete pressure measurements contribute to the inaccuracy of the BFFs and their implementation should be reevaluated

The Importance of Sustainability Aspects When Purchasing Online : Comparing Generation X and Generation Z

As research on sustainability orientation across generations is still sparse, we contribute to literature by enriching this research field, focusing on Generation Z (‘Zers’) and X (‘Xers’). Moreover, no other study has analyzed cross-generational differences in the sustainability context by making use of choice experiments, which overcome issues related to (Likert) scale item investigations, and allow respondents to evaluate the trade-off between different purchase factors simultaneously. We thus applied one of the most recent advancements in choice experiments, named Adaptive Choice-Based Conjoint analysis, which appears to be more realistic than previous alternatives. The results indicate Zers consume more sustainably (inter alia higher importance of social labels; higher purchase likelihood) when shopping online; however, differences within each generation were uncovered, especially among Xers (e.g., gender differences regarding importance of price)

Ares Launch Vehicle Transonic Buffet Testing and Analysis Techniques

It is necessary to define the launch vehicle buffet loads to ensure that structural components and vehicle subsystems possess adequate strength, stress, and fatigue margins when the vehicle structural dynamic response to buffet forcing functions are considered. In order to obtain these forcing functions, the accepted method is to perform wind-tunnel testing of a rigid model instrumented with hundreds of unsteady pressure transducers designed to measure the buffet environment across the desired frequency range. The buffet wind-tunnel test program for the Ares Crew Launch Vehicle employed 3.5 percent scale rigid models of the Ares I and Ares I-X launch vehicles instrumented with 256 unsteady pressure transducers each. These models were tested at transonic conditions at the Transonic Dynamics Tunnel at NASA Langley Research Center. The ultimate deliverable of the Ares buffet test program are buffet forcing functions (BFFs) derived from integrating the measured fluctuating pressures on the rigid wind-tunnel models. These BFFs are then used as input to a multi-mode structural analysis to determine the vehicle response to buffet and the resulting buffet loads and accelerations. This paper discusses the development of the Ares I and I-X rigid buffet model test programs from the standpoint of model design, instrumentation system design, test implementation, data analysis techniques to yield final products, and presents normalized sectional buffet forcing function root-mean-squared levels

Analysis of a Transonic Alternating Flow Phenomenon Observed During Ares Crew Launch Vehicle Wind Tunnel Tests

A transonic wind tunnel test of the Ares I-X Rigid Buffet Model (RBM) identified a Mach number regime where unusually large buffet loads are present. A subsequent investigation identified the cause of these loads to be an alternating flow phenomenon at the Crew Module-Service Module junction. The conical design of the Ares I-X Crew Module and the cylindrical design of the Service Module exposes the vehicle to unsteady pressure loads due to the sudden transition from separated to attached flow about the cone-cylinder junction with increasing Mach number. For locally transonic conditions at this junction, the flow randomly fluctuates back and forth between a subsonic separated flow and a supersonic attached flow. These fluctuations produce a square-wave like pattern in the pressure time histories which, upon integration result in large amplitude, impulsive buffet loads. Subsequent testing of the Ares I RBM found much lower buffet loads since the evolved Ares I design includes an ogive fairing that covers the Crew Module-Service Module junction, thereby making the vehicle less susceptible to the onset of alternating flow. An analysis of the alternating flow separation and attachment phenomenon indicates that the phenomenon is most severe at low angles of attack and exacerbated by the presence of vehicle protuberances. A launch vehicle may experience either a single or, at most, a few impulsive loads since it is constantly accelerating during ascent rather than dwelling at constant flow conditions in a wind tunnel. A comparison of a wind-tunnel-test-data-derived impulsive load to flight-test-data-derived load indicates a significant over-prediction in the magnitude and duration of the buffet loa

Managed Evolution of Automotive Software Product Line Architectures: A Systematic Literature Study

The rapidly growing number of software-based features in the automotive domain as well as the special requirements in this domain ask for dedicated engineering approaches, models, and processes. Nowadays, software development in the automotive sector is generally developed as product line development, in which major parts of the software are kept adaptable in order to enable reusability of the software in different vehicle variants. In addition, reuse also plays an important role in the development of new vehicle generations in order to reduce development costs. Today, a high number of methods and techniques exist to support the product line driven development of software in the automotive sector. However, these approaches generally consider only partial aspects of development. In this paper, we present an in-depth literature study based on a conceptual model of artifacts and activities for the managed evolution of automotive software product line architectures. We are interested in the coverage of the particular aspects of the conceptual model and, thus, the fields covered in current research and research gaps, respectively. Furthermore, we aim to identify the methods and techniques used to implement automotive software product lines in general, and their usage scope in particular. As a result, this in-depth review reveals that none of the studies represent a holistic approach for the managed evolution of automotive software product lines. In addition, approaches from agile software development are of growing interest in this field

Analysis of Ares Crew Launch Vehicle Transonic Alternating Flow Phenomenon

A transonic wind tunnel test of the Ares I-X Rigid Buffet Model (RBM) identified a Mach number regime where unusually large buffet loads are present. A subsequent investigation identified the cause of these loads to be an alternating flow phenomenon at the Crew Module-Service Module junction. The conical design of the Ares I-X Crew Module and the cylindrical design of the Service Module exposes the vehicle to unsteady pressure loads due to the sudden transition between a subsonic separated and a supersonic attached flow about the cone-cylinder junction as the local flow randomly fluctuates back and forth between the two flow states. These fluctuations produce a square-wave like pattern in the pressure time histories resulting in large amplitude, impulsive buffet loads. Subsequent testing of the Ares I RBM found much lower buffet loads since the evolved Ares I design includes an ogive fairing that covers the Crew Module-Service Module junction, thereby making the vehicle less susceptible to the onset of alternating flow. An analysis of the alternating flow separation and attachment phenomenon indicates that the phenomenon is most severe at low angles of attack and exacerbated by the presence of vehicle protuberances. A launch vehicle may experience either a single or, at most, a few impulsive loads since it is constantly accelerating during ascent rather than dwelling at constant flow conditions in a wind tunnel. A comparison of a windtunnel- test-data-derived impulsive load to flight-test-data-derived load indicates a significant over-prediction in the magnitude and duration of the buffet load. I. Introduction On