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Radiation treatment to the left breast is associated with increased cardiac morbidity as well as mortality. Deep inspiration breath-hold (DIBH) technique with Surface Guided Radiation Therapy (SGRT) could have dosimetric advantages over the free breathing technique (NB, normal breathing) in cardiac (heart and LAD) and ipsilateral lung sparing in patients with left-sided breast cancer after surgery. Therefore this technique was implemented in 2013 at the institute of radiooncology at the KFJ/SMZ-South – Hospital Vienna.

Due to the increase of volatile renewable energy resources, additional flexibility will be necessary in the electricity system in the future to ensure a technically and economically efficient network operation. Although home energy management systems hold potential for a supply of flexibility to the grid, private end users often neglect or even ignore recommendations regarding beneficial behavior. In this work, the social acceptance and requirements of a participatively developed home energy management system with focus on (i) system support optimization, (ii) self-consumption and self-sufficiency optimization, and (iii) additional comfort functions are determined. Subsequently, the socially-accepted flexibility potential of the home energy management system is estimated. Using methods of online household survey, cluster analysis, and energy-economic optimization, the socially-accepted techno-economic potential of households in a three-community cluster sample area is computed. Results show about a third of the participants accept the developed system. This yields a shiftable load of nearly 1.8 MW within the small sample area. Furthermore, the system yields the considerably larger monetary surplus on the supplier-side due to its focus on system support optimization. New electricity market opportunities are necessary to adequately reward a systemically useful load behavior of households.

Sustainable energy consumption behavior in households is a decisive factor in contributing to climate protection. To provide residents comprehensible insights into their household’s energy consumption data, nonintrusive load monitoring on appliance level can assist. To give consumers a simple and comprehensible overview of their consumption data, which they also find aesthetically pleasing, in this work a two-stage experimental design is used to compare the perceived aesthetic appearance of different types of electricity consumption graphs on appliance level (aggregated or time-dependent) and their triggered emotion. First, a representative survey covers the general aesthetics assessment in a 2x3 mixed factorial design. Second, an in-depth eye-tracking and facial expression investigation is used to track and quantify emotions on different electricity consumption graphs on application level and their perceived advantages and disadvantages. The main results provide comprehensive insights into the aesthetics of electricity consumption visualizations to trigger positive emotions, in particular users’ preferences for simple and conventional graphs like bar charts.

In this research the quality of the interconnects of the ultrasonically welded Cu terminals to the Cu substrate in the IGBT-module has been investigated. An ultrasonic resonance fatigue system in combination with a laser Doppler vibrometer and a special specimen design was used for shear fatigue testing of these large ultrasonic Cu-Cu welds (about 0.5 cm2). Fatigue life curves up to 109 loading cycles were obtained in a very short period of time. Using this technique it was possible to evaluate the fatigue strength of these interconnects for the first time. The microstructural features of the interconnects were characterized and their crack growth behaviour was studied. Fracture analysis of the fatigued specimen shows that failure occur due to the propagation of the crack beneath the welding interface into the copper substrate. Additionally performed finite element simulations offer an insight into the stress and strain concentrations during the mechanical fatigue tests. As this method is not restricted to the welding geometry, material joints with larger interconnects can be tested likewise. Thus this new technique can be used as a practical and valid fatigue testing method for evaluation of various interconnects.

In Industry 4.0, Cyber-Physical Systems (CPS) are formed by components, which are interconnected with each other over the Internet of Things (IoT). The resulting capabilities of sensing and affecting the physical world offer a vast range of opportunities, yet, at the same time pose new security challenges. To address these challenges there are various IoT Frameworks, which offer solutions for managing and controlling IoT-components and their interactions. In this regard, providing security for an interaction usually requires performing additional security-related tasks (e.g. authorisation, encryption, etc.) to prevent possible security risks. Research currently focuses more on designing and developing these frameworks and does not satisfactorily provide methodologies for evaluating the resulting costs of providing security. In this paper we propose an initial approach for measuring the resulting costs of providing security for interacting IoT-components by using a Security Cost Modell ing Framework. Furthermore, we describe the necessary building blocks of the framework and provide an experimental design showing how it could be used to measure security costs at runtime.

Many online services and their service providers require the electronic proof of identity for the secure authentication of citizens. Internet of Things (IoT)- and Cyber-Physical Systems (CPS)-services and devices are increasing and these are used in different areas. Furthermore, the increasing distribution of online services and IoT devices need to be monitored, especially in critical infrastructure. The proposal of a framework to authenticate and identify people, devices and services can be a useful tool to improve security and trust in CPS, linking them with identified people by utilizing and combining tools which do exist in isolation. IoT frameworks and identity protocols combined with responsible people, hardware, smartphone-applications, and certification authorities can provide secure authentication, trustworthy communication and the management of identities and permissions. This position paper proposes an IoT-framework for (critical infrastructure) service providers and public administration to authenticate, identify and manage their running devices and services as well as people, their electronic identification and sent records. This can improve the reaction time and processes additionally providing trust and secure communication between people, devices and services, especially for authorities in critical infrastructure areas, where humans and their safety are particularly important.

In the emerging industrial Internet of Things (IIoT) era, machine-to-machine (M2M) communication technology is considered as a key underlying technology for building IIoT environments, where devices (e.g., sensors, actuators, and gateways) are enabled to exchange information with each other in an autonomous way without human intervention. However, most of the existing M2M protocols that can be also used in the IIoT domain provide security mechanisms based on asymmetric cryptography resulting in high computational cost. As a consequence, the resource-constrained IoT devices are not able to support them appropriately and thus, many security issues arise for the IIoT environment. Therefore, lightweight security mechanisms are required for M2M communications in IIoT in order to reach its full potential. As a step toward this direction, in this paper, we propose a lightweight authentication mechanism, based only on hash and XOR operations, for M2M communications in IIoT environment. The proposed mechanism is characterized by low computational cost, communication, and storage overhead, while achieving mutual authentication, session key agreement, device's identity confidentiality, and resistance against the following attacks: replay attack, man-in-the-middle attack, impersonation attack, and modification attack.

Data with high security requirements is being processed and stored with increasing frequency in the Cloud. To guarantee that the data is being dealt in a secure manner we investigate the applicability of Assurance methodologies. In a typical Cloud environment the setup of multiple layers and different stakeholders determines security properties of individual components that are used to compose Cloud applications. We present a methodology adapted from Common Criteria for aggregating information reflecting the security properties of individual constituent components of Cloud applications. This aggregated information is used to categorise overall application security in terms of Assurance Levels and to provide a continuous assurance level evaluation. It gives the service owner an overview of the security of his service, without requiring detailed manual analyses of log files.

Ultrasonically bonded Al wire bonds on Al metallization pads are widely used in power semiconductors. The required long time reliability of the devices is highly dependent on the interfacial quality of Al wire and the bond pad. Reliability of wire bonds is commonly assessed by thermal and power cycling tests. Accelerated mechanical fatigue testing can be used as an alternative to these time consuming procedures. In the present study, lifetime of thick Al wedge bonds on Si substrates was investigated using a novel mechanical fatigue testing technique operating at high frequencies and elevated temperatures. The influence of microstructure, testing temperature and frequency on lifetime of Al wire bonds was investigated. Finite element analysis was applied to calculate the stress distribution at the interfacial region and to establish life time prediction curves. The results of mechanical isothermal fatigue curves were compared and correlated with thermal cycling data of Al wire bonds. © 2014 The Minerals, Metals & Materials Society.

Ultrasonically bonded A1 wire bonds on A1 metallization pads are widely used in power semiconductors. The required long time reliability of the devices is highly dependent on the interfacial quality of A1 wire and the bond pad. Reliability of wire bonds is commonly assessed by thermal and power cycling tests. Accelerated mechanical fatigue testing can be used as an alternative to these time consuming procedures. In the present study, lifetime of thick A1 wedge bonds on Si substrates was investigated using a novel mechanical fatigue testing technique operating at high frequencies and elevated temperatures. The influence of microstructure, testing temperature and frequency on lifetime of A1 wire bonds was investigated. Finite element analysis was applied to calculate the stress distribution at the interfacial region and to establish life time prediction curves. The results of mechanical isothermal fatigue curves were compared and correlated with thermal cycling data of Al wire bonds. Copyright © 2014 by The Minerals, Metals & Materials Society.

The rapid technological advancements and market demands in electronic sector requires application of highly accelerated, still practice relevant reliability assessment methods. At present, accelerated power and temperature cycling tests count as the state of the art for qualification of the devices. However due to physical characteristics of the devices, there are limitations to accelerated thermal and power cycling tests. Further acceleration by exceeding a critical temperature or time reduction may result in occurrence of failure mechanisms other than those encountered in real application or suppressing these failures. An alternative approach for further acceleration of the testing procedures is based on the application of isothermal mechanical fatigue testing at high frequencies (AMT). The principle idea of this approach is replacement of thermally induced strains by means of equivalent mechanical strains. Based on a physics of failure approach, the relevant failure modes in the material interfaces are induced enabling detection of weak sites of the devices in a very short duration of time. In addition of time saving factor a further advantage of mechanical fatigue testing is the possibility of decoupling of thermal, mechanical and environmental stress factors for a more effective investigation and diagnosis. This paper presents an overview of our recent reliability studies on different types of electronic components by using the proposed methodology with the aim to give an insights into the advantages and some restrictions of AMT for qualification of electronic devices.

In this study, a reaction mechanism is presented that is optimized for the simulation of the dual fuel combustion process using n-heptane and a mixture of methane/propane as surrogate fuels for diesel and natural gas, respectively. By comparing the measured and calculated ignition delay times (IDTs) of different homogeneous methane–propane–n-heptane mixtures, six different n-heptane mechanisms were investigated and evaluated. The selected mechanism was used for computational fluid dynamics (CFD) simulations to calculate the ignition of a diesel spray injected into air and a natural gas–air mixture. The observed deviations between the simulation results and the measurements performed with a rapid compression expansion machine (RCEM) and a combustion vessel motivated the adaptation of the mechanism by adjusting the Arrhenius parameters of individual reactions. For the identification of the reactions suitable for the mechanism adaption, sensitivity and flow analyzes were performed. The adjusted mechanism is able to describe ignition phenomena in the context of natural gas–diesel, i.e., dual fuel combustion.

This paper presents and investigates a novel, hybrid model predictive approach to control the auxiliary heating for a combistorage. Faulty design, as well as suitable design schemes cause situations in which solar energy supply has to “compete against” the auxiliary energy supply. This research demonstrates a feasible method to remedy such situations with the utilization of weather forecast data. The developed approach is modular and expandable to be used with additional heat sources. A suitable disturbance-prediction, which approximates the expected solar energy flux into the storage, in connection with a linear model predictive control (MPC), can prevent the auxiliary system to switch on at an early stage and thus reduce the auxiliary energy demand and keep storage capacity for solar thermal energy supply. Results obtained through simulations for selected months show a reduction of auxiliary energy demand up to 40%, when facilitating this approach for a solar thermal combisystem for a single family house. Monthly solar fractions (Fs) increase by approximately 4% points or 5% with respect to the base case.

Facing food insecurity and overuse of resources due to effects of climate change, humanity needs to find new ways to secure food production and produce close to consumers. Vertical farming, where plants are grown in vertical arrays inside buildings with help of Information and Communication Technology (ICT) components, could contribute to solving this issue. Such systems integrate heterogeneous devices on different computing layers and acquire a lot of data to monitor and optimize the production process. We created an indoor testing unit in which growing conditions can be monitored and controlled to optimize growth of microgreens. This setup includes an Indoor Farming Support as a Service (IFSaaS) prototype that provides safe and secure monitoring and controlling, as well as self-adaption of an indoor farming system. In this article we provide information about the combination of most suitable technologies.

Cyber-Physical Systems (CPS) are formed through interconnected components capable of computation, communication, sensing and changing the physical world. The development of these systems poses a significant challenge since they have to be designed in a way to ensure cyber-security without impacting their performance. This article presents the Security Cost Modelling Framework (SCMF) and shows supported by an experimental study how it can be used to measure, normalise and aggregate the overall performance of a CPS. Unlike previous studies, our approach uses different metrics to measure the overall performance of a CPS and provides a methodology for normalising the measurement results of different units to a common Cost Unit. Moreover, we show how the Security Costs can be extracted from the overall performance measurements which allows to quantify the overhead imposed by performing security-related tasks. Furthermore, we describe the architecture of our experimental testbed and demonstrate the applicability of SCMF in an experimental study. Our results show that measuring the overall performance and extracting the security costs using SCMF can serve as basis to redesign interactions to achieve the same overall goal at less costs.