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In dieser Dissertation wurde die Entwicklung von detaillierten und reduzierten kinetischen Mechanismen theoretisch für Ideal- und Realgas untersucht und mit experimentell erhaltenen Daten abgeglichen. Um Verbrennungsprozesse zu simulieren, sind kinetische Mechanismen nötig. Daher wurden in der ersten Stufe detaillierte Mechanismen für Methylester mit EXGAS entwickelt. Im zweiten Schritt war die große Auswahl von kinetischen Mechanismen zu reduzieren. Dafür wurde eine neue DRG-Generation Methode entwickelt, um die überflüssigen chemischen Spezies auszuschließen. Zusätzlich wurden die Sensivityanalyse, CSP und "Normalized Mole Fraction" NMF implementiert. Die neue DRG-Methode erwies sich als zuverlässige Reduktionsmethode. Reduzierte Skeletal-Mechanismen wurden erzielt für N-Heptan-, Iso-Oktan- und Methyl-Decanoate. Schließlich wurde für Methan-Oxygen-Systeme ein reduzierter Mechanismus abgeleitet, welcher nur aus wenigen globalen Reaktionsschritten besteht.

We consider the production and weak decay of a pair of heavy quarks (mesons) ine+e− experiments and study their effect on the various jet distributions. The relative magnitudes of the two-quark-jet and three-quark-jet final states, in the decay of a heavy quark are estimated in the framework of an SU(2)L×U(1) model. We find that the three quark configuration dominates over the two quark configuration. For the quark jets resulting from the weak decay of the heavy quarks, we calculate the jet distributions in Sphericity, Spherocity and Thrust for the process\(e^ +e^ -\to Q\bar Q \to 6\) quarks. These distributions are compared with the corresponding quantities from the non-perturbative process\(e^ +e^ -\to q\bar q\) and the QCD process\(e^ +e^ -\to q\bar qg\). We find that the weak decay of heavy quarks is the dominant mechanism for jet broadening ine+e− experiments, in the intermediate energy region relevant for PETRA and PEP. (1979). doi:10.1007/BF01445412

多様な気候型が存在する熊本県において，ススキ属の遺伝資源の探索を行った．その結果，ススキ (Miscanthus sinensis) 7点，トキワススキ (M. floridulus) 3点，オギ (M. sacchariflorus）21点を収集した．これらの材料は粗放栽培型牧草品種育成やバイオマス資源用品種育成に有効であると考えられた．

Wind energy holds significant importance in achieving the energy transition towards a sustainable, carbon-free energy future. The core technology has matured over the last decades, resulting in a substantial increase in installed capacity. While these advancements have led to considerable cost reductions, they have also brought about reductions in mechanisms supporting the economic viability of wind energy projects. Additionally, wind energy is required to play a more substantial role in supporting the electrical network, traditionally done by conventional generation technologies. However, wind energy differs fundamentally from these technologies in terms of cost allocation through the project's lifecycle and the ability to forecast and regulate energy production. These factors have given rise to new challenges for wind energy research, expanding its focus on topics such as enhancing grid integration, increasing profitability, and better utilization of existing farms through lifetime extension. The objective of this thesis is to support these goals by introducing a methodology for the management of long-term operational objectives, in terms of revenue and fatigue loading, based on adaptive control considering wind conditions and electricity prices. Currently, wind turbines produce power according to the wind conditions, operating in a single mode for most of their operational life. However, wind turbines have the capability to adjust their power output. They can operate in down-regulation, producing lower power than the baseline mode, which also decreases structural loading. Moreover, they can operate in power-boosting mode, which allows for exceeding the baseline power level at higher wind speeds with a tradeoff in structural loading. Additionally, modern turbines are capable of individually adjusting the pitch angle of each blade, enabling individual pitch control (IPC), which can reduce structural loading with the penalty of increased pitch actuator usage. These functionalities require mainly software modifications and can be applied to most machines, allowing for switching between modes according to an external decision-maker. The active management of power output and fatigue loading over time (e.g, in hourly intervals) according to wind conditions and electricity prices enables operational strategies for optimizing long-term objectives. Fatigue consumption and revenue generation can be effectively redistributed over time and conditions in an optimal manner, providing additional flexibility to both wind farm owners and grid operators. Exploring this research objective requires a multidisciplinary approach encompassing aspects of controller design, surrogate modeling, and optimization. As a first step, a multi-mode controller is synthesized, allowing adjustment of the power level between 50% and 130% of the baseline level and the optional application of an IPC loop. Two configurations are considered to assess the impact of the choice of down-regulation trajectory on structural load reduction. The IPC loop is based on an individual blade control (IBC) approach involving an independent controller for each blade. In the next step, a data-driven surrogate model is created based on mid-fidelity aeroelastic simulations. Two regression approaches are considered: a spline-based interpolation and a Gaussian process regression (GPR). The two methods performed very similarly with low uncertainty in their predictions, possibly due to the dense factorial sampling considered. The surrogate model is utilized to develop an evaluation-optimization framework for long-term operational strategies. As a monitoring tool, it resembles a digital twin, enabling the tracking of fatigue consumption across all components, revenue accumulation, and other metrics potentially useful for condition monitoring purposes based on input time series of wind and prices. Two optimization approaches are developed within this framework. The first employs as input the mean wind distribution, aiming to optimize the controller mode per wind speed, thereby creating a long-term operational schedule according to wind conditions. The second approach leverages forecasts of wind speeds and electricity prices to assign the optimal control mode per time step within the designated horizon. The proposed method is evaluated using two multi-year datasets, each representing distinct boundary conditions with regard to wind and price dynamics. Two optimization scenarios are considered, reflecting potential business cases: revenue maximization with a constraint on fatigue damage accumulation and fatigue damage minimization with constraints on cumulative revenue. This methodology is employed to assess the applicability and performance of the proposed operational approach for different objectives, considering both fixed and fluctuating market prices. Furthermore, it investigates the impact of controller design, optimization approach, and boundary conditions on the optimization outcomes. The results indicate that the method is able to concurrently optimize the revenue and fatigue loads in the long term. The two optimization approaches exhibited differences in terms of improvements achieved and the distribution of fatigue and revenue. Fatigue reduction was possible across all wind turbine components, suggesting that it can enable lifetime extension for the entire system while maintaining profitability. Revenue maximization cases showed higher dependency on the optimization approach and the maximum power boosting level considered. For the forecast-based optimization, the length of the horizon considered proved to be critical. For all cases, the most influential factor determining the extent of improvement was found to be the boundary wind and market dynamics. Overall, this thesis demonstrates that there is potential for optimizing long-term objectives using adaptive control, and it is worth exploring it further to address current research challenges in wind energy.

Modern society relies on convenience services and mobile communication. Cloud computing is the current trend to make data and applications available at any time on every device. Data centers concentrate computation and storage at central locations, while they claim themselves green due to their optimized maintenance and increased energy efficiency. The key enabler for this evolution is the microelectronics industry. The trend to power efficient mobile devices has forced this industry to change its design dogma to: ”keep data locally and reduce data communication whenever possible”. Therefore we ask: is cloud computing repeating the aberrations of its enabling industry?

Transport accounts for roughly one quarter of all greenhouse gas emissions (GHG) in Europe. Transport is the only sector that did not reduce its GHG in recent years. To meet the European and global targets to reduce GHG in industrialized countries by -80 to -95% until 2050 compared with 1990 requires that also the transport sector is put on a pathway to drastically reduce its emissions. The paper demonstrates that with a combined R&D and transport policy strategy reductions of -60 to -70% of GHG until 2050 will be achievable for the European transport sector. The analysis to develop the transport strategy combines an analysis of the innovation system of the transport sector with respect to developing GHG reduction technologies of all modes and a model-based quantitative scenario exercise to assess the transport impacts, economic and environmental impacts of the scenarios. We suppose to support R&D for biofuels for air transport and R&D for cross-modal transport. The policy strategy suggests in early years to focus on road transport (i.e. efficiency of ICE) and in medium time horizon on alternative energy technologies (i.e. electricity and hydrogen both from renewables). Additionally the transport strategy must include pricing measures and ambitious regulations (e.g. ban of fossil fuel cars in 2035).

Balancing financial performance and corporate sustainability is a challenge, especially in today’s economic environment. Based on the idea that there’s a trade-off between what’s “good for the business” and what’s “good for the environment and society,” companies sometimes perceive corporate sustainability and corporate social responsibility (CSR) as an add-on cost, or they may perceive sustainability as an opportunity for “green PR.” By doing so, they may miss significant opportunities for business growth, innovation, and organizational change. In this article, we describe how General Electric (GE) and Procter & Gamble (P&G) have operationalized corporate sustainability initiatives using management control and management accounting systems. Current forces of change are driving a general rethinking of business in a more sustainable direction. Pressures come from national and international regulatory bodies as well as from business partners, stakeholders, and activists. For instance, many companies require their suppliers to comply with standards for environmental management systems certification, such as the ISO 14000 series or the European Union’s Eco-Management and Audit Scheme.Moreover, thanks to new technologies, customers are increasingly informed, empowered, and active, and their demand for products that are clearly identified as sustainable is growing. Employees are also looking for companies that operate in a socially responsible way, which can impact the ability of an organization to recruit and retain talent. In addition, the financial community is paying closer attention to socially responsible investments (SRI) and investment rating systems such as the Dow Jones Sustainability Index. These internal and external stakeholder views shouldn’t be neglected by companies aiming to achieve superior corporate sustainability performance. As suggested in the May 2009 Strategic Finance article “Co-Creating Strategic Risk-Return Management” by Mark Frigo and Venkat Ramaswamy, “Sustainable wealth creation requires balanced risk taking by focusing on co-creation opportunities that can generate superior returns while simultaneously reducing risks for companies and their stakeholders.” Since shareholder value creation is driven from creating value for others (customers, employees, suppliers, and other stakeholders), organizations can think in terms of how these stakeholders can be engaged to help define and achieve sustainability performance. This process can help identify new sustainability opportunities that will create mutual value with internal and external stakeholders. The current drivers of change and the economic downturn provide an opportunity for more integrated, strategic, and value-creating sustainability efforts.

This paper empirically analyzes the determinants of individual tourism-related adaptation to climate change, i.e. the stated choice of alternative travel destina-tions due to increasing temperatures in the future. By examining the tourism sector, our study investigates an industry which was not extensively considered in economic analyses of climate change so far in spite of its worldwide huge eco-nomic relevance and strong sensitivity to global warming. Our empirical analysis on the basis of unique representative data from 5370 German tourists first re-veals a non-negligible extent of tourism-related adaptation to climate change in the amount of more than 22% of the respondents. Our micro-econometric analysis with binary probit models implies strong positive effects of a high awareness of climate change effects, increasing age as indicator for vulnerability of climate change, as well as a high adaptive capacity (measured by disposable financial resources) on this type of adaptation. The estimation results suggest no single significant effect of a high educational level or a high level of information on ad-aptation to climate change, but a positive interaction effect (which was, in con-trast to former studies, estimated according to Ai and Norton 2003 and Norton et al. 2004). Our empirical results underline several challenges for the tourism in-dustry and policy makers in order to transform the tourism infrastructure and to diversify holiday offers. They additionally reveal important focus groups of tour-ists such as (the increasing group of) elderly persons who are crucial for the de-velopment of successful future product strategies in the tourism sector.

11th International Fluid Power Conference, 11. IFK, Aachen, Germany, 19 Mar 2018 - 21 Mar 2018; Aachen : [Mainz], 72-81 (2018). Published by [Mainz], Aachen