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Energy budget, growth and exercise as proxies for performance capacity and fitness in Arctic fishes
Full text linkThe boreal Atlantic cod (Gadus morhua) is entering the Arctic in response to rising water temperatures, likely increasing predation pressure on the endemic key species Polar cod (Boreogadus saida). In this thesis, I investigated the whole-animal performance of both fish species after long-term acclimation to future ocean acidification and warming conditions in order to estimate their future competitive strength. More precisely, I focused on aerobic performance such as baseline and maximum metabolism, as well as energetic investment into growth and swimming as indicators for fitness capacity under future ocean conditions. While G. morhua was thriving under conditions projected for the year 2100, the competitive strength of B. saida likely decreases. F.i., the growth performance of B. saida decreased at temperatures above 6 degree Celsius and the swimming performance was impaired under elevated PCO2 levels, potentially resulting in a higher vulnerability to predation and reduced foraging success
Iran's foreign policy towards Afghanistan (2001-2014)
Full text linkThe present Ph.D. dissertation deals with the analysis of Irana s foreign policy towards Afghanistan from 2001 to 2014. The main purpose is to understand and explain the motives for Irana s contradictory behavior and actions with regard to its neighbouring country Afghanistan. The main research question is: a What is the nature of Irana s foreign policy towards Afghanistan from 2001 to 2014?a Conceptually, Irana s foreign policy is interpreted in the study from the realism (Hans Morgenthau; John Mearsheimer) perspective. This is done in a format that provides an overview of the history of Iran-Afghanistan relations, presents an in-depth analysis of the formal power structure of Iran, singles out four main visions of Irana s government which help to interpret the interplay of the three major foreign policy interests Iran has: security, political and economic interests. This is a qualitative study which makes use of historical reconstruction, content analysis, and the analysis of the semi-structured interviews, conducted in Iran and in Afghanistan as part of the field trip research. The analysis of the primary and secondary sources has enabled the answer of the research question on the nature of Irana s FP towards Afghanistan and revealed the contradictory policies of Iran vis-a-vis Afghanistan. The realism approach was assessed as an appropriate approach that adequately addressed Irana s three major foreign policy interests: security, political and economic and it provided explanations for the contradictory character of Irana s foreign policy. Nevertheless, realism was not able to fully unfold the peculiarities of the Iranian governmenta s geographical and cultural vision (the Shia factor). Towards this end, the suggestion for further studies would be to focus on this area in order to elucidate the cultural factor in Irana s FP towards Afghanistan
Retrieval of ozone profiles from OMPS-LP observations and merging with SCIAMACHY and SAGE II time series to study long-term changes
Full text linkStratospheric ozone is considered one of the most important trace gases in the atmosphere. After the strong ozone depletion observed at the end of last century, an ozone recovery is expected in the next decades, in response to the decreasing emissions of chlorine-containing ozone-depleting substances. This recovery is predicted to have a complex spatial structure and is modulated by the ongoing climate change. Within this framework, this dissertation is articulated in 3 main steps. First, the set-up of an ozone retrieval algorithm to be applied to limb observations from the OMPS-LP satellite instrument and its characterization in terms of error budget. Second, the comparison and the validation of the retrieved ozone profiles using independent data sets, e.g., ozonesondes and MLS. Third, the merging of OMPS-LP time series with other satellite data sets (in particular SCIAMACHY) to study long term changes over the last decades, as a function of altitude, latitude and longitude
Microbial composition in biofloc-based shrimp aquaculture systems
Full text linkShrimp disease outbreaks such as EMS can occur at the early post-stocking stage due to the presence of opportunistic pathogenic bacteria, such as species of Vibrio. EMS can cause up to 100% shrimp mortality and result in a 70% drop in total shrimp production. This bacteria-caused disease has led to the conclusion that sustainable shrimp aquaculture will depend on the development of bio-secure production systems, which need to be improved to ensure growth and disease resistance and facilitate bio-shrimp productivity towards sustainable aquaculture. This research work focused on improving the existing methods of disease prevention by examining the nature of shrimp-pathogen interactions to identify promising applications for shrimp farming, such as the use of bio-inoculants. To successfully use microbial composition in shrimp disease management, four different approaches to intensive shrimp aquaculture were compared with regard to the bacterial composition vs. biological and operational parameters. The results indicate that the total suspended solids (TSS) and pH are the most important indicating a systema s biosecurity (i.e. indicate the stability of parameters in a system). Overall, this thesis provides baseline information on bacterial ecology, intending to establish healthy super-intensive shrimp aquaculture with recommendations for best practices. As a future outlook, a shrimp eco-culture system is proposed with a high potential for contributing to responsible aquaculture. We propose a rapid beneficial bacteria kit, such as for Ruegeria sq1 and Pseudoalteromonas sq91 bacteria as r-matured bacteria, using biofloc technology as an alternative approach to controlling shrimp disease outbreaks via bacterial activity management
Externe Expertengemeinschaften im Produktionssektor- Orte gelingender Wissenskooperation : Grundlegung zu einer kritischen Theorie einer co-competitiven beruflichen Praxis von High Professionals
Full text linkObject of this study are external: interorganizational and globally operating communities of practice of high professionals (experts) in the production sector (i.e. automobile and defense weapons industry, aircraft manufacturer). The research question is: How and why will such a domain-specific and competitive practice of knowledge cooperation between experts succeed? The answer will be developed in a critical and transdisciplinary study. The question is discussed in a theoretical framework consisting of the theory of knowledge society, generative educational theory, the CoP-concept of E. Wenger, interaction economics, theories of social exchange, reciprocity and gift. Finally a turn to critical theory - reciprocal recognition theory and the concept of realabstraction (A. Toscano) inspired by K. Marx will fully answer the question of the internal logic and functionality of these communities. It is stated that a just knowledge exchange is the success principle of all communities of this type. The study develops a methodology called empirically informed theory building linking critical theory, constructivism and qualitative empirical research
Measurements of shipping emissions with in-situ instruments
No full textShipping is a major contributor to pollution in coastal areas and harbour towns. It is a growing industry and only few international regulations control its emissions. This thesis describes the set-up and analysis of in-situ measurements at different locations near the German coast, which are influenced by shipping emissions. It focusses on the analysis of a unique and extensive set of plumes measurements, which have been allocated with individual ships. A total of nearly 5 000 plumes could be analysed, especially with respect to their fuel sulphur content (FSC), based on SO2 measurements, and their NOx emission factors. The studies described in this thesis, which are the first of their kind in Germany in this extent, have laid the foundations for the future operational systems determining the pollution emissions from shipping and assessing their compliance with legislation
Nankai Trough fault slip behavior analyzed in-situ and in shear experiments
Full text linkThe Nankai Trough subduction zone hosts various modes of fault slip from slow to megathrust earthquakes. Slow earthquakes release energy slowly over days to years and can only be recorded geodetically or by borehole observatories. It is not well understood how they connect to regular earthquakes. In contrast, megathrust earthquakes are rapid events that often generate destructive tsunamis, documented for several centuries in the Nankai Trough. Successful earthquake mitigation strategies can only be developed with a better understanding of fault slip behavior and deformation processes within the seismogenic zone and the overlying accretionary prism
Alterung von Leistungshalbleitermodulen im Temperatur-Feuchte-Spannungs-Test
Full text linkFor a power semiconductor chip the most critical region is its junction termination. By the formation of a closed water film (monolayer electrolytic solution) linking the chip metallisation of the active area and the channel stopper metallisation or any other structure near the chip edge, a corrosion cell builds up. In case of copper and silver, the electro-chemical migration (ECM) occurs and forms dendrites of the metals at the active area metallisation. In case of aluminium, metal corrosion occurs leading to corrosion of the active area metal and precipitation at the outer part of the junction. This kind of degradation is usually investigated by means of accelerated testing, in this case by the High Humidity, High Temperature, Reverse Bias (H3TRB) test. Traditionally, end-of-life testing was done, but degradation occurs much earlier and, thus, this kind of test strategy is not sufficient. Instead, leakage monitoring and intermediate blocking measurements yield a much better estimation of the degradation status. The more detailed methods reveal a more complex degradation scenario
Security-Pattern Recognition and Validation
Full text linkThe increasing and diverse number of technologies that are connected to the Internet, such as distributed enterprise systems or small electronic devices like smartphones, brings the topic IT security to the foreground. We interact daily with these technologies and spend much trust on a well-established software development process. However, security vulnerabilities appear in software on all kinds of PC(-like) platforms, and more and more vulnerabilities are published, which compromise systems and their users. Thus, software has also to be modified due to changing requirements, bugs, and security flaws and software engineers must more and more face security issues during the software design; especially maintenance programmers must deal with such use cases after a software has been released. In the domain of software development, design patterns have been proposed as the best-known solutions for recurring problems in software design. Analogously, security patterns are best practices aiming at ensuring security. This thesis develops a deeper understanding of the nature of security patterns. It focuses on their validation and detection regarding the support of reviews and maintenance activities. The landscape of security patterns is diverse. Thus, published security patterns are collected and organized to identify software-related security patterns. The description of the selected software-security patterns is assessed, and they are compared against the common design patterns described by Gamma et al. to identify differences and issues that may influence the detection of security patterns. Based on these insights and a manual detection approach, we illustrate an automatic detection method for security patterns. The approach is implemented in a tool and evaluated in a case study with 25 real-world Android applications from Google Play
Multiprofessionelle Kooperation im Kontext des Trainingsraumes. Zwischen Anspruch und Wirklichkeit.
Full text linkViele Schulen verfügen über einen so genannten Trainingsraum, einen Ort, in dem Schüler/innen, die den Unterricht stören, befähigt werden sollen, ihr Handeln eigenverantwortlich zu reflektieren, neue Konfliktlösestrategien zu erlernen und ihr Verhalten im Sinne der institutionell erwünschten Normen und Werte zu modifizieren. Die Arbeit im und mit dem Trainingsraum stellt dabei ein schulpolitisch brisantes Themenfeld dar. Er ist ein Ort, an dem verschiedene pädagogische Berufsgruppen arbeiten, die jedoch primär unterschiedliche Handlungslogiken verfolgen. Dieser Aufsatz zielt auf die Darstellung der gelebten Praxis des Trainingsraumes einer Ganztags-Oberschule und den damit verknüpften Chancen und Risiken einer multiprofessionellen Arbeit zwischen den Lehrkräften und der Schulsozialarbeit ab. Eingerahmt wird dieser Aufsatz durch reflektierende Überlegungen zum Konzept der studentischen Praxisforschun