A method for developing Reference Enterprise Architectures

Industrial change forces enterprises to constantly adjust their organizational structures in order to stay competitive. In this regard, research acknowledges the potential of Reference Enterprise Architectures (REA). This thesis proposes REAM - a method for developing REAs. After contrasting organizations' needs with approaches available in the current knowledge base, this work identifies the absence of method support for REA development. Proposing REAM, the author aims to close this research gap and evaluates the method's utility by applying REAM in different naturalistic settings

Towards A Method for Developing Reference Enterprise Architectures

In most economic sectors organizations face rapid environmental changes like regulations. Such changes can force them to adjust both their organizational and operational structure. For instance, in the energy utility sector numerous developments moved German Public Utilities (PUs) towards a liberalized market. Nowadays PUs have to stay competitive while managing a heterogeneous information technology (IT) landscape. We address this demand for aligning business and IT by combining the holistic perspective of Enterprise Architecture Management (EAM) with the characteristic of reference modeling to reuse knowledge in a problem domain. Therefore, we utilize configurative reference modeling within Design Science Research (DSR). The artefact at hand is a method for developing a Reference Enterprise Architecture (R-EA), which is applied in the problem domain of PUs. Our contributions are the (i) adaptation of Configurative Reference Modelling (CRM) to develop a R-EA and (ii) a procedure how to elicit knowledge for R-EA development method

Collective dynamics in a monolayer of squirmers confined to a boundary by gravity

We present a hydrodynamic study of a monolayer of squirmer model microswimmers confined to a boundary by strong gravity using the simulation method of multi-particle collision dynamics. The squirmers interact with each other via their self-generated hydrodynamic flow fields and thereby form a variety of fascinating dynamic states when density and squirmer type are varied. Weak pushers, neutral squirmers, and pullers have an upright orientation. With their flow fields they push neighbors away and thereby form a hydrodynamic Wigner fluid at lower densities. Furthermore, states of fluctuating chains and trimers, of kissing, and at large densities a global cluster exist. Finally, pushers at all densities can tilt against the wall normal and their in-plane velocities align to show swarming. It turns into chaotic swarming for strong pushers at high densities. We characterize all these states quantitatively.DFG, 87159868, GRK 1558: Kollektive Dynamik im Nichtgleichgewicht: in kondensierter Materie und biologischen SystemenDFG, 237143019, SPP 1726: Mikroschwimmer - Von Einzelpartikelbewegung zu kollektivem VerhaltenTU Berlin, Open-Access-Mittel - 201

Gravity-induced dynamics of a squirmer microswimmer in wall proximity

We perform hydrodynamic simulations using the method of multi-particle collision dynamics and a theoretical analysis to study a single squirmer microswimmer at high Péclet number, which moves in a low Reynolds number fluid and under gravity. The relevant parameters are the ratio α of swimming to bulk sedimentation velocity and the squirmer type β. The combination of self-propulsion, gravitational force, hydrodynamic interactions with the wall, and thermal noise leads to a surprisingly diverse behavior. At α > 1 we observe cruising states, while for α < 1 the squirmer resides close to the bottom wall with the motional state determined by stable fixed points in height and orientation. They strongly depend on the squirmer type β. While neutral squirmers permanently float above the wall with upright orientation, pullers float for α larger than a threshold value ath and are pinned to the wall below αth. In contrast, pushers slide along the wall at lower heights, from which thermal orientational fluctuations drive them into a recurrent floating state with upright orientation, where they remain on the timescale of orientational persistence.DFG, 325093850, Open Access Publizieren 2017 - 2018 / Technische Universität Berli

Time Pressure and Regret in Sequential Search

Perceived urgency and regret are common in many sequential search processes; for example, sellers often pressure buyers in search of the best offer, both time-wise and in terms of potential regret of forgoing unique purchasing opportunities. theoretically, these strategies result in anticipated and experienced regret, which systematically affect search behavior and thereby distort optimal search. In addition, urgency may alter decision-making processes and thereby the salience of regret. To understand the empirical relevance of these aspects, we study the causal effects of regret, urgency, and their interaction on search behavior in a pre-registered, theory-based, and well-powered experiment. Empirically, we and that anticipated regret does not affect search behavior either with or without time pressure, while experienced regret leads to systematic adjustments in search length. Urgency reduces decision times and perceived decision quality, but does not generally alter search length. Only very inexperienced decision-makers buy earlier when pressured. Thus, consumer protection measures against pressure selling tactics can help inexperienced consumers in particular

A METHOD FOR CONTEXT MODELLING IN CAPABILITY MANAGEMENT

Enterprises exist in the context of their dynamically changing environment, which has a strong impact on service design and delivery. Within areas such as ambient intelligence or robotics, most relevant context has a physical nature. However, the context of an enterprise requires a different conceptual-ization of context awareness. Beyond physical context, enterprises need to be aware of their market, legal and social context. Moreover, in order to monitor context and configure services systematically, we need a context modelling method that is integrated within enterprise modelling and supports in-formation and communication technology (ICT) engineering and runtime. The work in this paper has been performed as part of developing Capability Driven Development (CDD), a new paradigm for ICT design where services are customised on the basis of the essential business capabilities and deliv-ery is adjusted according to the current context. The contributions of the paper are (i) the investiga-tion of industrial needs for context modelling, (ii) eCoM, a context modelling method for enterprise ICT addressing such needs, iii) application of the method in an industrial use case and (iv) the evolu-tion of eCoM based on various evaluation cycles by means of Framework for Evaluation in Design Science Research (FEDS)

Wear of Tailored Forming Steels

This study investigates the wear behavior of additively welded cladding layers on less wear-resistant base materials using plasma-transferred arc welding and laser hot-wire cladding. The cladding layers are made from atomized AISI 52100, AISI 5140, and a stainless steel with (0.52 wt% C, 0.9 wt% Si, 14 wt% Cr, 0.4 wt% Mo, 1.8 wt% Ni, 1.2 wt% V, bal. Fe) on unalloyed steel AISI 1022M as the base material. The specimens' microstructure and surface hardness are comparable with conventional specimens of monolithic AISI 52100 and AISI 4140, which is used as a reference. Tribometer tests are carried out in ball-on-disk configuration to investigate the wear resistance of the specimen. The multimaterial specimens show comparable wear behavior to their monolithic counterparts, and a good performance of the stainless specimen in pure sliding is proven. These findings suggest that additive manufacturing processes can be used to clad less wear-resistant base materials and achieve high wear resistance, making it possible to exploit the advantages of surface coatings under severe wear conditions