Uncertainty modeling of random and systematic errors by means of Monte Carlo and fuzzy techniques

The standard reference in uncertainty modeling is the “Guide to the Expression of Uncertainty in Measurement (GUM)”. GUM groups the occurring uncertain quantities into “Type A” and “Type B”. Uncertainties of “Type A” are determined with the classical statistical methods, while “Type B” is subject to other uncertainties which are obtained by experience and knowledge about an instrument or a measurement process. Both types of uncertainty can have random and systematic error components. Our study focuses on a detailed comparison of probability and fuzzy-random approaches for handling and propagating the different uncertainties, especially those of “Type B”. Whereas a probabilistic approach treats all uncertainties as having a random nature, the fuzzy technique distinguishes between random and deterministic errors. In the fuzzy-random approach the random components are modeled in a stochastic framework, and the deterministic uncertainties are treated by means of a range-of-values search problem. The applied procedure is outlined showing both the theory and a numerical example for the evaluation of uncertainties in an application for terrestrial laserscanning (TLS).DFG/KU/1250/4-

Estimation of Measurement Uncertainty of kinematic TLS Observation Process by means of Monte-Carlo Methods

In many cases, the uncertainty of output quantities may be computed by assuming that the distribution represented by the result of measurement and its associated standard uncertainty is a Gaussian. This assumption may be unjustified and the uncertainty of the output quantities determined in this way may be incorrect. One tool to deal with different distribution functions of the input parameters and the resulting mixed-distribution of the output quantities is given through the Monte Carlo techniques. The resulting empirical distribution can be used to approximate the theoretical distribution of the output quantities. All required moments of different orders can then be numerically determined. To evaluate the procedure of derivation and evaluation of output parameter uncertainties outlined in this paper, a case study of kinematic terrestrial laserscanning (k-TLS) will be discussed. This study deals with two main topics: the refined simulation of different configurations by taking different input parameters with diverse probability functions for the uncertainty model into account, and the statistical analysis of the real data in order to improve the physical observation models in case of k-TLS. The solution of both problems is essential for the highly sensitive and physically meaningful application of k-TLS techniques for monitoring of, e. g., large structures such as bridges

On the detection of systematic errors in terrestrial laser scanning data

Quality descriptions are parts of the key tasks of geodetic data processing. Systematic errors should be detected and avoided in order to insure the high quality standards required by structural monitoring. In this study, the iterative closest point (ICP) method was invested to detect systematic errors in two overlapping data sets. There are three steps to process the systematic errors: firstly, one of the data sets was transformed to a reference system by the introduction of the Gauss–Helmert (GH) model. Secondly, quadratic form estimation and segmentation methods are proposed to guarantee the overlapping data sets. Thirdly, the ICP method was employed for a finer registration and detecting the systematic errors. A case study was casted in which a dam surface in Germany was scanned by terrestrial laser scanning (TLS) technology. The results indicated that with the conjugation of ICP algorithm the accuracy of the data sets was improved approximately by 1.6 mm

Direct geo-referencing of a static terrestrial laser scanner

This paper describes an adaptive extended Kalman filter (AEKF) approach for geo-referencing tasks for a multi-sensor system (MSS). The MSS is a sensor fusion of a phase-measuring terrestrial laser scanner (TLS) with navigation sensors such as Global Navigation Satellite System (GNSS) equipment and inclinometers. The position and orientation of the MSS are the main parameters which are constant on a station and will be derived by a Kalman filtering process. Hence, the orientation of a TLS/MSS can be done without any demand for other artificial targets in the scanning area. However, using inclinometer measurements the spatial rotation angles about the X- and Y-axis of the fixed MSS station can be estimated by the AEKF. This makes it possible to determine all six degrees of freedom of the transformation from a sensor-defined to a global coordinate system. The paper gives a detailed discussion of the strategy used for the direct geo-referencing. The AEKF for the transformation parameters estimation is presented with focus on the modelling of the MSS motion. The usefulness of the suggested approach will be demonstrated using practical investigations

Synthesis, biological evaluation and SAR study of novel pyrazole analogues as inhibitors of Mycobacterium tuberculosis

As a continuation of our previous work that turned toward the identification of antimycobacterial compounds with innovative structures, two series of pyrazole derivatives were synthesized by parallel solution-phase synthesis and were assayed as inhibitors of Mycobacterium tuberculosis (MTB), which is the causative agent of tuberculosis. One of these compounds showed high activity against MTB (MIC = 4 μg/mL). The newly synthesized pyrazoles were also computationally investigated to analyze their fit properties to the pharmacophoric model for antitubercular compounds previously built by us and to refine structure–activity relationship analysis

German and European Ground Motion Service: a Comparison

Since the end of 2022, two ground motion services that cover the complete area of Germany are available as web services: the German Ground Motion Service (Bodenbewegungsdienst Deutschland, BBD) provided by the Federal Institute for Geosciences and Natural Resources (BGR), and the first release of the European Ground Motion Service (EGMS) as part of the Copernicus Land Monitoring Service. Both services are based on InSAR displacement estimations generated from Sentinel‑1 data. It would seem relevant to compare the products of the two services against one another, assess the data coverage they provide, and investigate how well they perform compared to other geodetic techniques. For a study commissioned by the surveying authority of the state of Baden-Württemberg (Landesamt für Geoinformation und Landentwicklung Baden-Württemberg, LGL), BBD and EGMS data from different locations in Baden-Württemberg, Saarland, and North Rhine-Westphalia (NRW) were investigated and validated against levelling and GNSS data. We found that both services provide good data quality. BBD shows slightly better calibration precision than EGMS. The coverage provided by EGMS is better than that of BBD on motorways, federal roads, and train tracks of the Deutsche Bahn. As an example, where both services have difficulties in determining the correct displacements, as they cannot be described well by the displacement models used for processing, we present the test case of the cavern field at Epe (NRW). Finally, we discuss the implications of our findings for the use of the products of BBD and EGMS for monitoring tasks

Geodäsie im gesellschaftlichen Kontext

Die Geodäsie ist eine traditionsreiche Disziplin, deren Bedeutung für Wissenschaft, Politik und Verwaltung sowie für die Gesellschaft insgesamt in den vergangenen zwei bis drei Jahrzehnten im Zuge verschiedener Entwicklungen noch einmal deutlich zugenommen hat. In diesem Beitrag wird diese Situation am Beispiel der Erdmessung aus drei verschiedenen Perspektiven betrachtet: Geodäsie als Wissenschaft, Geodäsie als Methode und Geodäsie als Beruf. Es wird argumentiert, dass die Geodäsie über diese drei Perspektiven hinweg verschiedene Alleinstellungsmerkmale aufweist, die sie mehr denn je zu einer wichtigen Partnerdisziplin im interdisziplinären Umfeld machen

The Archaeological Site HLO1 - A Bronze Age Copper Mining and Smelting Site in the Emirate of Sharjah (U.A.E.)

The site HLO1 in the Wadi al-Hilo, which means “Hilo river valley”, in the Emirate of Sharjah, UAE, has been excavated since 2007 by a Joint Project of the Directorate of Antiquities of the Government of Sharjah and the Institute of Pre- and Protohistory of Tübingen University under the direction of Sabah A. Jasim from the Sharjah side and Margarethe Uerpmann and Hans-Peter Uerpmann from the Tübingen side. The author was in charge of the actual excavations at the site from 2007 to 2012 and, under the supervision of Ernst Pernicka and Gregor Markl, of the evaluation of finds and findings presented in this dissertation. The site is situated near the upper end of the valley. Its name translates as “sweet valley”, which is due to its fertility and the rich supply of fresh water in its alluvial underground. Geologically, the area is dominated by Gabbro of the Oman–UAE Ophiolite, which contains small occurrences of copper ore. Some of them indicate traces of surface mining, including a locality at the northern periphery of the archaeological site. Indications for copper smelting at the site begin during the transition from the Neolithic to the Bronze Age. At present, this is the earliest proof for metallurgy in SE Arabia. Indications for continued occupation of the site during the Bronze and Iron Ages exist in the form of typical pottery from these periods. Direct and indirect evidence for metal production was found in the form of smelting furnaces, workshops, and traces of ore processing. An ingot of pure copper with a weight of 4.6 kg—which, according to the lead isotopes, was produced from local ore—is direct evidence for on-site metallurgy. Isotope analyses of artefacts from other Bronze Age sites indicate that HLO1 is a potential source of copper for a larger area of SE Arabia. The economic importance of the site and its products is indicated by traces of fortifications. The most obvious is the base of a watchtower of the Umm an-Nar period excavated near the southern access to the site. Traces of a fortification wall were found along the northern border of the site. The stone foundations of a house with several rooms are the only indication for potential domestic buildings. This house was later transformed into a workshop. Presumably, wooden huts, which have left no traces, served as housing for the prehistoric population. An additional outcome of the excavations at HLO1 is the evidence for a Neolithic occupation of the site. Unfortunately, the only evidence for that period are five radiocarbon dates for fireplaces which span the time from the 9th to the 4th millennium BC. Based on stratigraphy, a partly excavated stone structure also belongs to this period. Some few flint artefacts from the corresponding levels are insufficiently characteristic for a typological characterization. Obvious ruins indicate human presence during the historic period in the form of fairly well preserved rural buildings in the north of the site. They seem to form a “socio-economic unit”, which as such seemed deserving of detailed description before their state of preservation deteriorates further. A large number of presumably Islamic graves were spared from excavation. A well preserved Islamic watchtower at the southern entrance of HLO1 and the ruins of a noble house on the other side of the wadi indicate that the ecological advantages of the area attracted people at all times.Die Fundstelle HLO1 im Wadi Hilo (Emirat Sharjah, VAE) wird seit 2007 von einem gemeinsamen Projekt des Instituts für Naturwissenschaftliche Archäologie der Universität Tübingen unter Leitung von Margarethe und Hans-Peter Uerpmann und des Antikendirektorats des Emirats Sharjah (VAE) unter Leitung von Sabah A. Jasim untersucht. Der Autor dieser Dissertation hat die Grabungen an der Fundstelle HLO1 von 2007 bis 2012 geleitet. Die Auswertung von Funden und Befunden unter Anleitung durch Ernst Pernicka und Gregor Markl sind Gegenstand der vorliegenden Dissertation. Die Fundstelle liegt am oberen Ende des Wadi Hilo auf einer alten Wadi Terrasse am Ostrand des Tales. Sein Name bedeutet "`Süßes Tal"', was sich auf seine Fruchtbarkeit und den Reichtum an Wasser in seinem alluvialen Untergrund bezieht. Geologisch wird die Gegend durch Gabbro-Formationen des Oman-VAE-Ophioliths bestimmt, der kleine Vorkommen von Kupfererz enthält. Einige davon zeigen Hinweise auf einen obertägigen Abbau, darunter auch ein kleines Vorkommen nahe der Fundstelle. Hinweise auf Kupferverhüttung am Fundplatz beginnen am Übergang vom Neolithikum zur Bronzezeit. Derzeit sind dies die ältesten Spuren metallurgischer Aktivitäten in Südost-Arabien. Eine Besiedlung des Fundplatzes von der Bronze- bis zur Eisenzeit wird durch charakteristische Keramik-Funde dieser Perioden belegt. Direkte und indirekte Belege für die Erzverhüttung liegen in Form von Schmelzöfen, Werkstätten, Schlacken und Spuren der Erz-Aufbereitung vor. Der Fund eines Barrens aus reinem Kupfer mit einem Gewicht von 4,6kg – der nach Ausweis der Blei-Isotopie aus lokalem Erz gewonnen wurde – ist ein klarer Beleg für Kupfergewinnung vor Ort. Isotopenanalysen an Bronzefunden anderer Fundstellen weisen darauf hin, dass HLO1 eine potentielle Produktionsstätte von Kupfer für größere Gebiete in SO-Arabien gewesen ist. Die ökonomische Bedeutung der Fundstelle und ihrer Produkte ergibt sich aus den Spuren einer aufwendigen Befestigungsanlage. Ihr auffälligster Bestandteil ist der Stumpf eines Turmes, der in die Umm an-Nar Phase der Frühen Bronzezeit datiert. Er liegt auf der Südseite der Fundstelle und kontrolliert den dortigen Zugang. Weniger gut erhaltene Spuren einer Befestigungsanlage wurden entlang der Nordseite gefunden. Grundmauern eines Hauses mit mehreren Räumen sind die einzigen Spuren potenzieller Wohnbauten. Dieses Haus wurde später zu einer metallurgischen Werkstätte umgebaut. Vermutlich hat die prähistorische Bevölkerung in Holzbauten gelebt, die keine archäologischen Spuren hinterlassen haben. Ein zusätzliches Ergebnis der Ausgrabungen sind die klaren Hinweise auf eine Nutzung der Fundstelle im Neolithikum. Leider besteht der Nachweis für die Periode nur aus fünf Radiocarbon-Daten, die den Zeitraum vom 9. bis ins 4. Jahrtausend v. Chr. belegen. Auf Grund der Stratigraphie gehört auch eine partiell ergrabene Steinstruktur zu dieser Periode. Einige Silexartefakte aus den zugehörigen Schichten sind zu uncharakteristisch um eine typologische Zuordnung zu ermöglichen. Augenfällige Ruinen belegen die menschliche Anwesenheit in historischer Zeit. Diese liegen am Nordrand der Fundstelle. Da sie die sozio-ökonomische Struktur der Ansiedlung widerspiegeln, rechtfertigten sie eine detaillierte Beschreibung und Dokumentation bevor sie weiter zerfallen