Description: This brochure is designed for scientists and engineers of upcoming drilling projects and explains the key steps and important challenges in planning and executing continental scientific drilling.

Description: 47th IAMSLIC Annual Conference and 19th EURASLIC Regional Meeting held 12-14 October, 2021 Virtually via Galway, Ireland

Description: 37th IAMSLIC Conference & 5th AFRIAMSLIC Conference, Zanzibar, Tanzania, October 16-21, 2011

Description: 32nd Annual Conference of IAMSLIC held 8-12 October, 2006 at Portland, Oregon, USA

Description: SummaryThe aim of this study was to identify scientific criteria and to acquire performance data for the development of mariculture in the context of sustainable multifunctional use of offshore space and natural resources.In connection with current plans for a massive expansion of wind farms in offshore areas of the North Sea, the idea emerged to combine these with the installation of extensive mariculture for bivalves and macroalgae. Since offshore wind farms provide safety from shipping and infrastructure for attachment and service support, the opportunity for a multiple-use concept presented itself. However, prior to such a multifunctional development, it is necessary to determine the appropriate biological, technological and management requirements as well as the performance characteristics that would allow the employment of favourable and cost-effective methodologies. To this end, spezial focus was placed on the combination of extensive offshore shellfish and seaweed farming at exposed sites within the proposed offshore wind farms.This thesis deals in detail with1. the effects of abiotic and biotic factors on the growth potential of indigenous macroalgae and bivalves in extensive mariculture systems exposed to the stressful conditions of offshore habitats: (a) effects of physical forces on the cultivated species, (b) various parameters characterising the growth performance of species, (c) testing these parameters while using a variety of substrates and technical setups, (d) survival and health conditions, (e) recruitment, (f) parasite infestation of mussels in relation to inshore and offshore exposure, and (g) site-specific responses of the species to the various harsh offshore environments,2. the interaction between physical offshore processes and man-made structures in areas of the German North Sea Territory where mariculture has potential,3. the conditions for possible combination of mariculture systems with offshore wind farms in terms of the legal framework and possible management strategies, and4. the socio-economic and legal consequences and interactions for offshore mussel farming with the existing conventional inshore bottom culture activities.The research locations were specifically selected sites in the offshore region of the German Bight, mainly in the outer estuary of the River Weser, the offshore waters off the Island of Helgoland, several offshore areas where wind farms are planned, and habitats along the northern part of the Island of Sylt.In this yet relatively young research field the performance of different offshore culture systems with attached macroalgae (Laminaria saccharina) and blue mussels (Mytilus edulis) was assessed at monthly sampling intervals. These procedures were carried out using research vessels, boats and scuba surveys, while determining morphometric parameters (e.g. length, width, thickness) as well as weight for growth analysis of mussels and seaweeds. Furthermore, the condition index, the meat content and the degree of parasite infestation of blue mussels were determined. The abundance of mussel larvae in the water column and the resulting settlement success of post-larvae on various spat collectors were investigated. Seaweed studies included attachment strength, breaking and drag forces on kelp sporophytes in order to describe the resistance of cultivated Laminarians to high energy environments. Additional assessment criteria were biochemical parameters (e.g. chlorophyll-, nutrient-, POC- and TON-concentrations and their ratios) to describe the food availability for mussels and the nutrient composition for algal growth as well as oceanographic parameters (currents, waves, swell, salinity, temperature, light attenuation) to describe the wave climate and current velocities of the study sites in the offshore environment. Technical studies comprised two system designs (longline, ring structure) of various set ups (submerged or floating mode) in different locations (offshore or inshore) to find an appropriate culture design to sustain growth and survival of cultivated species. Further, a specially designed offshore spat collector was used for settlement investigations of mussel post larvae. Some fundamental studies were carried out in order to pave the way for the realisation of open ocean aquaculture in offshore wind farms (e.g. multifunctional use of offshore habitats in terms of avoidance of stakeholder conflicts, the legal framework for such activities in coastal areas and in the Exclusive Economic Zone (EEZ), the multi-use concept in terms of integrated coastal zone management).Laminaria saccharina showed sufficient length increments in offshore habitats growing on a submerged ring system. It could be demonstrated by drag and breaking-/dislodgement force experiments that algae were capable of resisting the high-energy environment of the North Sea. The concentration of mussel larvae in the water column decreased offshore and resulted in a low settlement success while at the same time infestation load decreased and was lacking at offshore suspended collectors. The three system designs showed different results. While the offshore ring proved to be superior for seaweed cultivation under the harsh conditions, the longline showed some major drawbacks in terms of materials used, design and installation modes (submerged or floating). The spat collector largely withstood the harsh hydrodynamic conditions of the North Sea. The hitherto fragmented legal framework for the offshore waters was found to be one of the key constraints for the successful implementation of multifunctional use schemes. However, participation of all involved stakeholders may provide a window of opportunity to turn the existing lack of offshore regulations into a positive momentum, as scope exists to move with the development of new offshore co-management concepts beyond existing management approaches.Whether such offshore installations would provide sufficient economic returns could not be answered yet, as experience on the maintenance of offshore wind farms is lacking so far.However, the discovery that Laminaria saccharina resists offshore forces and shows sufficient length increments and mussels growing in offshore habitats are not affected by parasites may provide a key incentive for positive commercial use.It thus can be shown that there is a high potential for farming the deep blue in the German EEZ, provided that some of the constraints, of which the lack of legal framework and technical aspects seems to be most severe, are resolved in the near future.

Description: The Global Geodetic Reference Frame (GGRF) plays a fundamental role in geodesy and related Positioning, Navigation, and Timing applications, and allows to quantify the Earth’s change in space and time. The ITRF and ICRF are the two most important components to realize GGRF, while the determination of these two reference frames relies on the combination of several space geodetic techniques, mainly, VLBI, SLR, GNSS, and DORIS. The combination is currently done on either the parameter level, or the normal equation level. However, the combination on the observation level, or the so-called integrated processing of multi-technique on the observation level, provides the results of best consistency, robustness, and accuracy. This thesis focuses on the investigation of the integrated processing of GNSS and VLBI on the observation level. The benefits of integrated processing are demonstrated in terms of TRF, CRF, and EOP, while the impact of global ties (EOP), tropospheric ties, and local ties are underlined. Several issues in integrated processing are addressed, including the systematic bias in ties (for instance, LOD and tropospheric ties), the relative weighting. An automatic reweighting strategy based on the normalized residuals is developed, which can properly handle the uncertainty of the ties without losing too much constraint. A software with state-of-the-art modules is the prerequisite to perform integrated processing. Based on the GNSS data processing software: Positioning And Navigation Data Analyst (PANDA), the VLBI and SLR modules are implemented in the common least-squares estimator. Therefore, the best consistency can be guaranteed. The software capability is demonstrated with the single-technique solutions. The station coordinate precision is at millimeter level for both GNSS and VLBI, while the EOP estimates are comparable to other Analysis Centers and the IERS products. It is also demonstrated that the SLR station coordinate precision is improved by 20% to 30% with additional GLONASS and GRACE satellites to contributing to the LAGEOS and ETALON constellation. Focusing on the tropospheric ties in GNSS and VLBI integrated processing, its contribution is demonstrated for the first time comprehensively. Applying tropospheric ties improves the VLBI station coordinate precision by 12% on the horizontal components and up to 30% on the vertical component. The network scale repeatability is reduced by up to 33%. The EOP estimates are also improved significantly, for instance, 10% to 30% for polar motion, and up to 10% for other components. Furthermore, applying the gradient ties in the VLBI intensive sessions reduces the systematic bias in UT1-UTC estimates. The consistent TRF, CRF, and EOP are achieved in the integrated VLBI and GNSS solution. Applying the global ties, tropospheric ties, and local ties stables the reference frame. The ERP estimates in the integrated solution are dominated by the GNSS technique, and the VLBI technique introduces additional 10% improvement on the y-pole component in terms of the day-boundary-discontinuity. The UT1-UTC and celestial pole offsets are also slightly improved in the integrated solution. It is also demonstrated that applying the LTs inappropriately distorts the network and introduces systematic biases to the ERP estimates, addressing the necessity of updating the local surveys. Moreover, the coordinates of AGN are also enhanced by up to 20% in the integrated solutions, especially the southern ones. This study reveals the importance of integrated processing of multi-technique on the observation level, as the best consistency can be achieved, and the applied ties improve the solutions significantly. It is strongly recommended that for the future realization of celestial and terrestrial reference frames, the concept of integrated processing on the observation level should be implemented, and all the possible ties should be applied, including the global ties (EOP), local ties, space ties, and tropospheric ties. Such kind of integrated solution of all the four techniques can provide robust estimates of the reference frames and EOP, with the advantage of each technique exploited to its full extend.

Description: Der Globale Geodätische Referenzrahmen (Global Geodetic Reference Frame, GGRF) spielt eine fundamentale Rolle in der Geodäsie und den damit verbundenen Positionierungs-, Navigations- und Zeitmessungsanwendungen (Positioning, Navigation, and Timing, PNT) und ermöglicht die Quantifizierung der Veränderung der Erde in Raum und Zeit. Der ITRF und der ICRF sind die beiden wichtigsten Komponenten zur Realisierung des GGRF, wobei die Bestimmung dieser beiden Referenzrahmen auf der Kombination verschiedener raumgeodätischer Techniken beruht, hauptsächlich VLBI, SLR, GNSS und DORIS. Die Kombination wird derzeit entweder auf der Parameterebene oder auf der Normalgleichungsebene durchgeführt. Die Kombination auf der Beobachtungsebene oder die sogenannte integrierte Daten-Verarbeitung von Multi-Techniken auf der Beobachtungsebene, bietet jedoch eine Lösung mit der besten Konsistenz, Robustheit und Genauigkeit. Diese Arbeit konzentriert sich auf die Untersuchung der integrierten Daten-Verarbeitung von GNSS und VLBI auf der Beobachtungsebene. Die Vorteile der integrierten Lösung werden in Bezug auf TRF, CRF, und EOP aufgezeigt, während die Auswirkungen von „Global Ties (EOP), Tropospheric Ties, and Local Ties“ hervorgehoben werden. Einige Punkte der integrierten Verarbeitung werden in dieser Arbeit untersucht, einschließlich der systematischen Abweichungen von „Ties“ (z.B. LOD und Tropospheric Ties), der relativen Gewichtung usw. Anhand der normalisierten Residuen wird eine automatische Umgewichtungsstrategie entwickelt, mit der die Unsicherheit der „Ties“ angemessen behandelt werden kann, ohne dass zu viel Einschränkung dabei verloren geht. Eine Software mit modernsten Modulen ist die Voraussetzung für die integrierte Daten Verarbeitung. Basierend auf der GNSS-Datenverarbeitungssoftware Paket: Positioning And Navigation Data Analyst (PANDA) werden die Module VLBI und SLR in demselben Least-Squares-Estimator wie GNSS implementiert, damit kann man die beste Konsistenz in der Datenverarbeitung erreichen. In dieser Arbeit wird die Leistungsfähigkeit der Software mit den Ein-Technik-Lösungen demonstriert. Die Genauigkeit der Stationskoordinaten liegt sowohl für GNSS als auch für VLBI im Millimeterbereich, und die geschätzten EOP-Parameter sind auch mit der anderer Analysezentren und den IERS-Produkten vergleichbar. Es wird auch gezeigt, dass die Koordinatengenauigkeit der SLR-Station um 20-30% verbessert wird, wenn zusätzliche GLONASS- und GRACE-Satelliten zur LAGEOS und ETALON-Konstellation beitragen. Mit dem Schwerpunkt auf den „Tropospheric Ties“ in der integrierten GNSS- und VLBI- Daten Verarbeitung wird ihr Beitrag zum ersten Mal umfassend dargestellt. Die Anwendung der „Tropospheric Ties“ verbessert die Genauigkeit der VLBI-Koordinaten um 12% bei der horizontalen Komponente und bis zu 30% bei der vertikalen Komponente. Die Genauigkeit im Netzwerkmaßstab wird um bis zu 33% verbessert. Auch die EOP-Bestimmungen werden deutlich verbessert, z.B. um 10-30% bei polaren Bewegungen und bis zu 10% bei anderen Komponenten. Darüber hinaus reduziert die Einführung der „Gradient Ties“ in der VLBI-Intensivsession die systematische Abweichung in den dUT1-Bestimmungen. Die konsistente TRF, CRF, und EOP werden bei der integrierten VLBI- und GNSS-Lösung erreicht. Die Anwendung der „Global Ties, Tropospheric Ties and Local Ties“ stabilisiert die Bestimmungen des Referenzrahmens. Die ERP-Bestimmungen in der integrierten Lösung werden von der GNSS-Technik dominiert, und die VLBI-Technik bringt eine zusätzliche Verbesserung um 10% auf die Tagesgrenzen-Diskontinuität (day-boundary-discontinuity, DBD) für die y-Pol-Komponente. Die dUT1- und CPO werden in der integrierten Lösung ebenfalls leicht verbessert. Es wird auch gezeigt, dass eine ungeeignete Anwendung der LTs das Netzwerk verzerrt und systematische Abweichungen in die ERP-Bestimmungen einführt, wodurch die Notwendigkeit einer Aktualisierung der lokalen Tie Messungen deutlich wird. Darüber hinaus werden die Koordinaten der AGN in den integrierten Lösungen um bis zu 20% verbessert, insbesondere im Süden. Diese Arbeit zeigt die Bedeutung der integrierten Daten Verarbeitung von Multi-Technik auf der Beobachtungsebene, da die beste Konsistenz erreicht werden kann und die angewandten „Ties“ die Lösungen erheblich verbessern. Es wird nachdrücklich empfohlen, für die zukünftige Realisierung von himmelsfesten und erdfesten Referenzrahmen das Konzept der integrierten Verarbeitung auf Beobachtungsebene durchzuführen und alle möglichen „Ties“ anzuwenden, einschließlich der „Global Ties (EOP), Local Ties, Space Ties, and Tropospheric Ties“. Eine solche integrierte Lösung aller vier Techniken kann die robusten Bestimmungen der Referenzrahmen und der EOP liefern, wobei die Vorteile jeder Technik voll ausgeschöpft werden.