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Development and application of a climate emulator
No full textLinear and nonlinear response functions (RF) are extracted for the climate system and the carbon cycle represented by the MPI-ESM and cGENIE models, respectively. Appropriately designed simulations are run for this purpose. Joining these RFs, we have a climate emulator with carbon emissions as the forcing and any desired observable quantity (provided the data is saved), such as the surface air temperature or precipitation, as the predictand. Like e.g. for atmospheric CO2 concentration, we also have RFs for the solar constant as a forcing — mimicking solar radiation management (SRM) geoengineering. We consider two application cases. 1. One is based on the Paris 2015 agreement, determining the necessary least amount of SRM geoengineering needed to keep the global mean surface air temperature below a certain threshold, e.g. 1.5 or 2 [oC], given a certain amount of carbon emission abatement (ABA) and carbon dioxide removal (CDR) geoengineering. 2. The other application considers the conservation of the Greenland ice sheet (GrIS). Using a zero-dimensional simplification of a complex ice sheet model, we determine (a) if we need SRM given some ABA and CDR, and, if possible, (b) the required least amount of SRM to avoid the collapse of the GrIS. Keeping temperatures below 2 [oC] even is hardly possible without sustained SRM (1.); however, the collapse of the GrIS can be avoided applying SRM even for moderate levels of CDR and ABA, an overshoot being affordable (2.)
Potential for the Development of Service Business Models Through Digital Services and the Active Inclusion of Customers
No full textAs one of the most important branches of the industry in Germany and
the European Union, the mechanical and plant engineering sector is confronted with fundamental changes due to ever shorter innovation cycles and increased competitive pressure. This makes it even more important to increase the level of service components in business models with a low service level, which are still frequently found in SMEs. This paper is dedicated to the changes that the individual components of a business model have experienced and will experience. Special attention is paid to economic sustainability, since service business models can also positively influence the long-term nature of a business. Seven interviews conducted with relevant companies serve as the empirical basis of this paper. The analysed effects of smart services and active customer integration are structured and summarized within the three pillars of every business model (value proposition, the value creation architecture and the revenue mechanic)
Simplifying Vulnerability-Scan Results
Get PDFThis thesis emphasizes problems that reports generated by vulnerability scanners impose on the process of vulnerability management, which are a. an overwhelming amount of data and b. an insufficient prioritization of the scan results.
To assist the process of developing means to counteract those problems and to allow for quantitative evaluation of their solutions, two metrics are proposed for their effectiveness and efficiency. These metrics imply a focus on higher severity vulnerabilities and can be applied to any simplification process of vulnerability scan results, given it relies on a severity score and time of remediation estimation for each vulnerability.
A priority score is introduced which aims to improve the widely used Common Vulnerability Scoring System (CVSS) base score of each vulnerability dependent on a vulnerability’s ease of exploit, estimated probability of exploitation and probability of its existence.
Patterns within the reports generated by the Open Vulnerability Assessment System (OpenVAS) vulnerability scanner between vulnerabilities are discovered which identify criteria by which they can be categorized from a remediation actor standpoint. These categories lay the groundwork of a final simplified report and consist of updates that need to be installed on a host, severe vulnerabilities, vulnerabilities that occur on multiple hosts and vulnerabilities that will take a lot of time for remediation. The highest potential time savings are found to exist within frequently occurring vulnerabilities, minor- and major suggested updates.
Processing of the results provided by the vulnerability scanner and creation of the report is realized in the form of a python script. The resulting reports are short, straight to the point and provide a top down remediation process which should theoretically allow to minimize the institutions attack surface as fast as possible. Evaluation of the practicality must follow as the reports are yet to be introduced into the Information Security Management Lifecycle
A triangle-shape region of interest in cardiorespiratory estimation during sleep monitoring
No full textSimulation of the Mixed Lubrication Regime of Foil-Air Bearings
Get PDFFoil-air bearings (FABs) are predominantly used for high-speed, oil-free applications. Offering many advantages such as friction loss at high speeds, stability and price, they lack, however, load capacity as well as start-up and coast-down friction wear resistance.
The friction losses of FABs have been studied experimentally by many authors. In order to predict the friction and, consequently, the lifespan of a FAB, the start-up and coast-down regimes are modelled in such a way that allows for accurate, efficient simulation and later optimisation of lift-off speed and wear characteristics. The proposed simulation method applies the Kirchhoff-Love plate theory to the top foil mapping [20]. This system of differential equations is coupled with the underlying compliant foil to simulate the displacement due to the pressure buildup. Consequently, this coupled system allows for simulation from almost zero rounds per minute (rpm) to full speed. The underlying simulation model uses the finite difference method for spatial discretisation and a temporal explicit Runge-Kutta method.
Difficulties to overcome are the smooth combination of various friction regimes across the sliding surfaces as well as the synchronous coupling of Reynolds, deformation and kinematic equations with highly non-linear terms. Introducing an exponential pressure component based on Greenwood and Tripp’s theory avoids impingement between the rotor and foil
Klassische Teilzeit und Brückenteilzeit
Get PDFTeilzeitmodelle sind beliebt und haben für viele Mitarbeiter einen ernsten Hintergrund. Ihre Lebensentwürfe lassen schlicht keine andere Form der Arbeit zu. Arbeitgeber sollten einerseits auf die Flexibilisierungswünsche der Betroffenen eingehen, um das Betriebsklima zu fördern und eine Unternehmensbindung herzustellen. Andererseits sind sie aber (mit wenigen Ausnahmen) verpflichtet, Teilzeit zu ermöglichen. Eine Variante ist dabei die Brückenteilzeit, also eine zuvor festgelegte (nur) zeitlich begrenzte Verringerung der Arbeitszeit
MPPI Control of a Self-Balancing Vehicle Employing Subordinated Control Loops
No full textRecently published nonlinear model-based control
approaches achieve impressive performances in complex real-
world applications. However, due to model-plant mismatches
and unforeseen disturbances, the model-based controller’s per-
formance is limited in full-scale applications. In most applica-
tions, low-level control loops mitigate the model-plant mismatch
and the sensitivity to disturbances. But what is the influence
of these low-level control loops? In this paper, we present
the model predictive path integral (MPPI) control of a self-
balancing vehicle and investigate the influence of subordinate
control loops on closed-loop performance. Therefore, simulation
and full-scale experiments are performed and analyzed. Subor-
dinate control loops empower the MPPI controller because they
dampen the influence of disturbances, and thus improve the
model’s accuracy. This is the basis for the successful application
of model-based control approaches in real-world systems. All
in all, a model is used to design a low-level controller, then
its closed-loop behavior is determined, and this model is used
within the superimposed MPPI control loop – modeling for
control and vice versa
Common Data Environment (CDE): Das digitale Werkzeug für ein besseres Daten- und Informationsmanagement im Bauwesen
Get PDFThe architecture, engineering and construction (AEC) industry is currently in transformation. Within this transformation, digitalization has a leading function, whereby a higher level of efficiency is pursued. In order to ensure a coordinated information exchange within the digitalization, the concept of the Common Data Environment (CDE) has been developed in the last years. A CDE is a cloud based collaborative platform that is used to exchange project information and data between the different stakeholders of a construction project. The main objective of this thesis is the implementation of a suitable CDE solution for the purpose of a construction management company.
For this purpose, an evaluation of different CDE software on the market, based on the functions and usability of the different software, has been complied to identify the most suitable solution. Secondly, a concept for the setup and implementation of a CDE solution has been developed. Therefore, advice for a successful change-management has been established to ensure the good implementation of the CDE.
The first part of the thesis includes a literature review through which the current state of the information management in the AEC industry is analyzed. The advantages of a CDE for the information management are also analyzed. Therefore, a synthesis of the functions and requirements to a CDE has been complied.
The second part of the thesis links the concept of Building Information Modelling (BIM) with the CDE. The advantages of a CDE in the BIM process has been established.
The third part of the thesis treats the evaluation of CDE software. This evaluation has been complied with a scoring method. As basis of the evaluation, a requirement list has been developed in which all the required functions of a CDE are listed.
In the fourth part of the thesis, a concept for the establishment of a CDE has been developed. The developed concept is a practical application of the standards specifications to CDE. The concept has been developed with CDE expert and CDE power users. The developed concept treats overall of the structuration, the standardization, and the implementation of a CDE.
The last part treats of the change process engender by the implementation of a CDE.
Summary, this thesis provides a structure for the implementation of a CDE software and serves as framework for companies of the AEC industry to select and establish a CDE
Wien, Berlin, Porto, Paris, Stuttgart, Wien...
No full textTrotz des seit über zehn Jahren anhaltend negativen Trends im traditionellen Kameramarkt werden in Zukunft exponentiell mehr Bilder mit technischen Hilfsmitteln produziert und veröffentlicht werden, nur eben auf eine fundamental andere Weise, mit anderen, vermeintlich komfortableren Geräten, im Hintergrund unterstützt durch sogenannte »smarte« Technologien. Die blitzschnelle Verrechnung von kurzen Bildserien zu einem einzigen Bild, unter Zuhilfenahme von leistungsfähigen Algorithmen aus dem Bereich des maschinellen Sehens, simuliert eine handwerkliche Perfektion, die auf optisch, chemischem Weg so nicht möglich wäre. Auch wenn die analoge Fotografie, teils im Rückgriff auf Jahrhunderte alte Praktiken der Bildenden Kunst, einstmals die Vorbilder und Standards etabliert hat, auf die KI-Modelle derzeit trainiert werden, spielen analoge Bildgebungsverfahren heutzutage quantitativ kaum mehr eine Rolle. Qualitativ erfährt die analoge Fotografie, sowohl im Sinne einer entschleunigenden Gegenbewegung, als auch auf Grund ihrer vermeintlich höheren Authentizität und ihrer haptischen und materiellen Qualitäten, eine überraschend starke Aufmerksamkeit. Diese richtet sich auf die Auseinandersetzung mit fotografischen Wahrnehmungsweisen, die Erforschung unserer realen Umgebung und nicht zuletzt auf die Begegnung mit uns selbst. Analoge Kameras, die Arbeit in der Dunkelkammer und historische Verfahren, wie das Nasse-Kollodion-Verfahren oder die Cyanotypie haben seit einigen Jahren weltweit wieder Konjunktur unter Photoenthusiasten und Studierenden. Was die Protagonisten eines vermeintlich nostalgischen Retro-Trends indes nicht davon abhält, in ihrem Alltag ganz selbstverständlich in »Echtzeit« mit Handys und häufig unter strategisch diversifizierten, mehr oder weniger privaten User-Profilen und Identitäten in den sogenannten sozialen Netzwerken mit anderen (und auch sich selbst) in Form von digitalen bzw. digitalisierten Bildern in einen möglichst flüchtigen Kontakt zu treten