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For axial piston units, product optimisation plays an essential role in the development phase, where an efficient and price-attractive product design and manufacturing process is the key to the success of a product. Moreover, the market needs are on lighter, more compact, efficient, and reliable products designed to the limit. Therefore, reliability is the focus of this work, where the research includes method analysis of the material stress calculation applied to the cylinder block implemented in an axial piston pump. A simplified calculation model is presented and evaluated concerning load while remaining accessible for users without deep technical knowledge or access to expensive Finite Element (FE) simulation tools. The analytical calculation method delivers a stress distribution intended for different purposes like design evaluation or as load spectrum for lifetime calculation. Additionally, the developed calculation method is generalised, enabling the methodology to be used on any standard axial piston pump. The methodology utilises the stress determination model, which includes the load as a sum of forces caused by the external and internal influencing factors. To show the method’s success, a comparison demonstrates strong positive agreement between the calculated and simulated stress results obtained by Finite Element Analysis.

Industrial Digitalization and Automation (DA), promoted through new production paradigms such as Industry 4.0 currently dominates the strategy agendas of industrial companies. However, practitioners report various problems while implementing DA into their organizations work-routines. We find underlying problems in missing operational monitoring systems to assess and control the DA-implementation status. We therefore propose a holistic monitoring system using 143 developed DA-implementation key performance indicators in nine dimensions. Moreover, we integrate the monitoring system into a continuous improvement approach following the PDCA-circle. First applications show increased objectivity during initial KPI-status assessments, higher acceptance of defined KPI-target-states and increased alignment during definition of future DA-projects.

Industrial enterprises increasingly identify their employee's digital competences as a main barrier towards modern manufacturing paradigms - such as Industry 4.0. Considering shorter technology cycles, they find a key enabler in timely capturing existing digital competences to forecast future competence requirements relating to identified trends. To support digital competence planning in practise, we developed a digital competence maturity model (DigiCoM), consisting of 49 attributes in four dimensions to measure maturity on individual employee level. The model considers digital competences required for direct value creation activities as well as competences in supporting areas. We tested the model in several use-cases, whereby two use-cases in SMEs are presented in detail. Result evaluation shows that the proposed approach makes digital competences visible and measurable and builds the basis for the derivation of competence developments. The DigiCoM therefore allows interconnecting strategic human resource planning with operational employee competences on an individual level.

The consideration of the drivetrains behavior under real operating conditions is becoming increasingly important. While in the past decades it was good enough to have a rough knowledge about the operation conditions in field, a more accurate and detailed picture of the duty cycles is required today. Caused by specific and complex operation conditions the load deviation between different applications is significant. In many cases like e.g. lifetime calculation, a precise knowledge of field conditions leads to the more accurate calculated or simulated results. This paper covers the duty cycles investigation of a forwarder application in field including the measurement concept and implementation. Especially, the analysis of the load conditions, clustering algorithm and lifetime calculation is included. The load spectrum generation is consequently done based on comprehensive load cycle determination. The Aim of this work is to verify the calculation accuracy of the load spectrum by using the clustered and raw data. The outcome of the investigation gives an indicator for the load degree of the drivetrain. Here the developed method creates a new and fast possibility of data analysis and is applicable to most drivetrain applications. Furthermore, the collected data is used as reference for future investigation of the forwarder evolution.

The need for improvement of lifetime prediction of hydrostatic axial piston units is driven by partly outdated knowledge dating back to the 1970s and is also motivated by a significant evolution of hydrostatic drivetrains. However, the evolution of the load life is unknown and must be investigated. An additional aspect for the method improvement is the potential decrease of qualification effort caused by required evaluation background. The goal is an increase in the prediction accuracy of the lifetime by using of qualitative and quantitative calculation methods. This paper covers the analysis phase of the lifetime calculation improvement. Hence, the currently used calculation method is investigated and the improvement potential builds the research approach. The improvement potential covers calculation model of load-dependent treatment, where the characteristics of sub-components build a system assessment. The aim includes the representative load cycle acquisition for typical applications in the off-road market.

Manufacturing enterprises are currently facing substantial challenges with regard to disruptive concepts such as the Internet of Things, Cyber Physical Systems or Cloud-based Manufacturing - also referred to as Industry 4.0. Subsequently, increasing complexity on all firm levels creates uncertainty about respective organizational and technological capabilities and adequate strategies to develop them. In this paper we propose an empirically grounded novel model and its implementation to assess the Industry 4.0 maturity of industrial enterprises in the domain of discrete manufacturing. Our main goal was to extend the dominating technology focus of recently developed models by including organizational aspects. Overall we defined 9 dimensions and assigned 62 items to them for assessing Industry 4.0 maturity. The dimensions ""Products"", ""Customers"", ""Operations"" and ""Technology"" have been created to assess the basic enablers. Additionally, the dimensions ""Strategy"", ""Leadership"", Governance, ""Culture"" and ""People"" allow for including organizational aspects into the assessment. Afterwards, the model has been transformed into a practical tool and tested in several companies whereby one case is presented in the paper. First validations of the model's structure and content show that the model is transparent and easy to use and proved its applicability in real production environments.

The occurrence of similar code, or ‘code clones’, can make program code difficult to read, modify and maintain. This paper describes industrial case studies of clone detection and elimination, and were were performed in collaboration with engineers from Ericsson AB using the refactoring and clone detection tool Wrangler for Erlang.\ud \ud We use the studies to illustrate the complex set of decisions that have to be taken when performing clone elimination in practice; we also discuss how the studies have informed the design of the tool. However, the conclusions we draw are largely language-independent, and set out the pragmatics of clone detection and elimination in real-world projects as well as design principles for clone detection decision-support tools.\ud \ud Context. The context of this work is the fact that a software tool is designed to be used; the success of such a tool therefore depends on its suitability and usability in practice.\ud \ud The work proceeds by observing the use of a tool in particular case studies in detail, through a “partici- pant observer” approach, and drawing qualitative conclusions from these studies, rather than collecting and analysing quantitative data from a larger set of applications. Our conclusions help not only programmers but also the designers of software tools.\ud \ud Inquiry. Data collected in this way make two kinds of contribution. First, they provide the basis for deriving a set of questions that typically need to be answered by engineers in the process of removing clones from an application, and a set of heuristics that can be used to help answer these questions. Secondly, they provide feedback on existing features of software tools, as well as suggesting new features to be added to the tools.\ud \ud Approach. The work was undertaken by the tool designers and engineers from Ericsson AB, working to- gether on clone elimination for code from the company.\ud Knowledge. The work led to a number of conclusions, at different levels of generality.\ud \ud At the top level, there is overwhelming evidence that the process of clone elimination cannot be entirely automated, and needs to include the input of engineers familiar with the domain in question.\ud \ud Furthermore, there is strong evidence that the automated tools are sensitive to a set of parameters, which will differ for different applications and programming styles, and that individual clones can be over- and under-identified: again, involving those with knowledge of the code and the domain is key to successful application.\ud \ud Grounding. The work is grounded in “participant observation” by the tool builders, who made detailed logs of the processes undertaken by the group.\ud \ud Importance. The work gives guidelines that assist an engineer in using clone detection and elimination in practice, as well as helping a tool developer to shape their tool building. Although the work was in the context of a particular tool and programming language, the authors would argue that the high-level knowledge gained applies equally well to other notions of clone, as well as other tools and programming languages.

Analyzing a communication protocol by means of simulation and real-world experimentation requires careful protocol implementation in both domains. Differences in the implementation may lead to significantly diverging performance results, which may affect the protocol design process adversely. A code-transparent simulation and experimentation framework for Wireless Access Research Platform (WARP) devices is proposed, which is called WARPsim. By extending the simulation engine appropriately, the same application code that runs on WARP devices can be used for simulation. This work studies the implications of this approach using the example of implementing time-critical Medium Access Control Layer (MAC) protocols on WARP devices. In the demonstration, various MAC protocols will be simulated using WARPsim, while changing protocol parameters, but also crucial aspects of the emulated hardware. A graphical representation integrated into the framework allows for an intuitive examination of the protocol behavior.

Presently, Central European waterways are utilized below their capacities while traffic volume on rail and road is increasing constantly. Especially road transport leads to high external costs caused by air pollution or congestion. Facing these problems, a new inland waterway ship called NEWS (FP7 Project, Development of a Next generation European inland Waterway Ship and logistics system) is being constructed. The resource efficiency is going to be increased by up to 30% due to the adjustable LNG-gas-electric propulsion system. Additionally the fuel consumption can be decreased by 10% due to a new hull design. The main targets of this new development are to reduce greenhouse gas emissions and other pollutants and to shift transport volumes from the road to inland waterways to enable sustainable freight transport. This new development will be integrated in a ready-to-use inland waterway transport concept to fulfil the goals for competitive and resource efficient transport of the European Commission.

Semiconductor wafer bonding has increasingly become a technology of choice for materials integration in microelectronics, optoelectronics, and microelectromechanical systems. The present overview concentrates on some basic issues associated with wafer bonding such as the reactions at the bonding interface during hydrophobic and hydrophilic wafer bonding, as well as during ultrahigh vacuum bonding. Mechanisms of hydrogen-implantation induced layer splitting (“smart-cut” and “smarter-cut” approaches) are also considered. Finally, recent developments in the area of so-called “compliant universal substrates” based on twist wafer bonding are discussed.

In microsystems technologies, frequently complex structures consisting of structured or plain silicon or other wafers have to be joined to one mechanically stable configuration. In many cases, wafer bonding, also termed fusion bonding, allows to achieve this objective. The present overview will introduce the different requirements surfaces have to fulfill for successful bonding especially in the case of silicon wafers. Special emphasis is put on understanding the atomistic reactions at the bonding interface. This understanding has allowed the development of a simple low temperature bonding approach which allows to reach high bonding energies at temperatures as low as 150°C. Implications for pressure sensors will be discussed as well as various thinning approaches and bonding of dissimilar materials.

Lie detection procedures typically aim at determining the guilt or innocence of a single suspect. The Concealed Information Test (CIT), for example, has been shown to be highly successful in detecting the presence or absence of crime-related information in a suspect’s memory. Many of today’s security threats, however, do not come from individuals, but from organized groups such as criminal organizations or terrorist networks. In this study, we tested whether a plan of an upcoming mock terrorist attack could be extracted from a group of suspects using a dynamic questioning approach. One-hundred participants were tested in 20 groups of 5. Each group was asked to plan a mock terrorist attack based on a list of potential countries, cities, and streets. Next, three questions referring to the country, city, and street were presented, each with five options. Skin conductance in all five members of the group was measured simultaneously during this presentation. The dynamic questioning approach entailed direct analysis of the data, and if the average skin conductance of the group to a certain option exceeded a threshold, this option was followed up, e.g., if the reaction to the option “Italy” exceeded the threshold, this was followed up by presenting five cities in Italy. Results showed that in 19 of the 20 groups the country was correctly detected using this procedure. In 13 of these remaining 19 groups the city was correctly detected. In 7 of these 13, the street was also correctly detected. The question about the country resulted in no false positives (out of 20), the question about the city resulted in two false positives (out of 19), while the question about the streets resulted in two false positives (out of 13). Furthermore, the two false positives at the city level also yielded a false positive at the street level. Even though effect sizes were only moderate, these results indicate that our dynamic questioning approach can help to unveil plans about a mock terrorist attack.

In Schaltanlagen des Niederspannungsnetzes konnen Storlichtbogen zu erheblichen Schaden fuhren. Die Ursache der Lichtbogen ist vielfaltig und reicht von Uberschlagen an Isolationsstrecken uber Blitzeinschlage in das Netz bis zu Kurzschlussen, die bei Wartungs- oder Montagearbeiten verursacht werden konnen. Die Wirkungen von Storlichtbogen sind erheblich und konnen die Zerstorung der Schaltanlage zur Folge haben. Die Klockner-Moeller GmbH hat ein Storlichtbogenschutzsystem (ARCON) entwickelt, das in die Schaltanlagen integriert wird. Da das Auftreten der Storlichtbogen nicht vorhersehbar ist, wird die gesamte Schaltanlage von Sensoren auf der Basis von Lichtwellenleitern uberwacht. Fur diesen Einsatzzweck sind die Sensoren so konzipiert, dass das Licht des Bogens nicht uber die Stirnflache des Lichtleiters, sondern seitlich uber den Mantel in den Kern eingekoppelt wird. Die Leuchterscheinungen jedes sich bildenden Lichtbogens konnen von dem Sensor erfasst und an einen Detektor weitergeleitet werden, dessen Signal die Schutzmasnahmen einleitet. Dadurch kann der Strom noch wahrend der ersten Halbwelle abgeschaltet und der Schaden begrenzt werden.

Although industrial decision makers show increased readiness to invest in their company’s digital transformation – currently referred to as Industry 4.0, they lack knowledge regarding their current status in Industry 4.0 and strategic guidance towards its realization. In this paper, we present a holistic procedure model that guides manufacturing companies from their first contact with Industry 4.0 until the definition of concrete action fields and their realization. Our model thereby builds on the maturity assessment of 65 critical success factors in Industry 4.0 and their sequencing to create company specific realization-paths and roadmaps following a 10-step approach. We validated und improved the model over a time-period of two years, whereby one application from a manufacturing company - aiming for the creation of their global Industry 4.0 strategy – will be presented.