15 research outputs found
Land use dynamics in favorable and unfavorable areas of southwest Germany
Since the “Neolithic Revolution” and the beginning of agriculture in central Europe about 7.500 a ago human influence on the environment is increasing. Human activities led to quasi-natural relief formation and created in many places a cultural landscape. Colluvial deposits are the correlate sediments of human induced soil erosion on slopes and depict an excellent archive for land use and landscape history. The present study combines pedological, archaeological and palynological analyses and knowledge with AMS 14C and luminescence datings to build up a stratigraphy of colluvial deposits, thereby allowing the reconstruction of past land use dynamics southwest Germany.
Compared with Black Forest and the Swabian Jura, the Baar is a favorable area for agricultural land use, where seven main phases of colluvial deposition could be detected. Increased colluviation, and thus land use intensity, took place during the younger Neolithic, the early to middle Bronze Age, the Iron Age, the Roman Empire, and in three phases from the High Middle Ages onwards. The southeastern Black Forest low mountain range is an unfavorable area characterized by low temperatures, high precipitation and steep slopes. Nevertheless, human influence dates back to the Neolithic. Minor colluvial deposition phases were detected before the Middle Ages and increased formation of colluvial deposits during the High Middle Ages and the Modern Times. The colluvial stratigraphy shows an intense land use of the Black Forest area from the Middle Ages onwards. In the western Swabian Jura the pattern of colluvial deposition indicates land use from the Bronze Age onwards and for one site even since the Neolithic.
The different land use dynamics in the Baar area compared to the Black Forest and Swabian Jura will be discussed against the paleoenvironmental conditions reconstructed from different archives. It is to analyze whether climate was the main determining factor for the settlement pattern in time and space or if there were other factors responsible, such as: different human motivations to settle the land depending on natural or cultural resources, conflicts in neighboring areas or trading relations. Feedback mechanisms of the anthropogenically modified landscape might also interact and determine settlement and land use dynamics
Model Calculations for a Pushbroom Stereo Camera - The Case of the Mars 94 High Resolution Stereo Camera (HRSC)
Report is a guideline for the understanding of the complex relationships between the requirements and the design parameters of a stereo camera for planetary remote sensing. The model calculations include astronomical parameters, orbit data, viewing geometry, radiometry, contrast assessments, camera operations as well as image analysis aspects
A Widget Based Operations Simulator for a Planetary Camera - A Model for the High Resolution Camera on Mars 94
Soil cultures - the adaptive cycle of agrarian soil use in Central Europe: an interdisciplinary study using soil scientific and archaeological research
Today's global challenges (e.g., food security) are not unprecedented in human history. Starting with the Neolithic transition, the agricultural sector and society underwent several cultural and technological changes and endured natural challenges. These challenges and changes are analyzed by using the adaptive cycle metaphor and the social-ecological system as tools to show the complexity of human-environment interactions and their development. The analysis relies on archaeological, pedological, and botanical research, and demonstrates the importance of interdisciplinary work. Agrarian soil use as a social-ecological system persisted in Central Europe for 7000 years and underwent an adaptive cycle from the Neolithic transition to industrialization. With agriculture's mechanization, a second adaptive cycle started. The resilience of agrarian soil use for thousands of years shows that agriculture, as a human-environmental interaction, is adaptive to change. Understanding past agricultural challenges and changes using archaeological and soil scientific data puts the present development into a new perspective. A cultural perspective on soils might trigger soil protection and sustainable land use in a technical as well as political domain. Applying social-ecological system and adaptive cycle concepts to this interdisciplinary reconstruction of agrarian soil use illustrates their usefulness for archaeology and soil science
High Resolution Stereo Camera (HRSC) Mars 94 Mission Consolidated Phase A Conception; Part B: Technical Description
Model calculations for a pushbroom stereo camera - the case of the Mars 94 high resolution stereo camera (HRSC)
With 125 figs., 44 refs.SIGLEAvailable from TIB Hannover: RN 437(90-57) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Evaluation of different fiducial markers for image-guided radiotherapy and particle therapy
Factors influencing the performance of patient specific quality assurance for pencil beam scanning IMPT fields.
PURPOSE
A detailed analysis of 2728 intensity modulated proton therapy (IMPT) fields that were clinically delivered to patients between 2007 and 2013 at Paul Scherrer Institute (PSI) was performed. The aim of this study was to analyze the results of patient specific dosimetric verifications and to assess possible correlation between the quality assurance (QA) results and specific field metrics.
METHODS
Dosimetric verifications were performed for every IMPT field prior to patient treatment. For every field, a steering file was generated containing all the treatment unit information necessary for treatment delivery: beam energy, beam angle, dose, size of air gap, nuclear interaction (NI) correction factor, number of range shifter plates, number of Bragg peaks (BPs) with their position and weight. This information was extracted and correlated to the results of dosimetric verification of each field which was a measurement of two orthogonal profiles using an orthogonal ionization chamber array in a movable water column.
RESULTS
The data analysis has shown more than 94% of all verified plans were within defined clinical tolerances. The differences between measured and calculated dose depend critically on the number of BPs, total thickness of all range shifter plates inserted in the beam path, and maximal range. An increase of the dose difference was observed with smaller number of BPs (i.e., smaller tumor) and smaller ranges (i.e., superficial tumors). The results of the verification do not depend, however, on the prescribed dose, NI correction, or the size of the air gap. There is no dependency of the transversal and longitudinal spot position precision on the beam angle. The value of NI correction depends on the number of spots and number of range shifter plates.
CONCLUSIONS
The presented study has shown that the verification method used at Centre for Proton Therapy at Paul Scherrer Institute is accurate and reproducible for performing patient specific QA. The results confirmed that the dose discrepancy is dependent on the size and location of the tumor