DYNAMIC BUSINESS MODELS: A COMPREHENSIVE CLASSIFICATION OF LITERATURE

Business models are vital to companies’ success; to stay competitive, companies continuously adapt and innovate their business model. The conceptualisation of business models has received much attention from prior research and the focus of research is shifting from a static perspective to a more dynamic perspective. This research is a comprehensive and up-to-date literature analysis of the concept of dynamic business models. To achieve a systematic and objective penetration of the research field, we used a classification framework consisting of 15 evaluation dimensions. We identified the main research streams on the topic and present the most relevant approaches, such as system dynamics modelling. A total of 42 relevant literature sources were found. Finally, we highlighted gaps for future research, such as a need for more detailed analyses of the interdependencies between the components a business models consists of

Adoption of Software Platforms: Reviewing Influencing Factors and Outlining Future Research

Software platforms have received attention as the dominant model for cooperative software development. Growing the ecosystems around software platforms through increasing adoption by users and developers is of great importance for platform owners. However, there is a lack of research on how to increase adoption and growth of software platforms systematically. To address this issue, we conduct a literature review and make an in-depth analysis to uncover and organize factors that drive adoption of software platforms. Additionally, we derive effective directions of these factors on the respective sides. Finally, we outline three avenues for future research: aligning research on platform governance and platform launch and growth, taking an evolutionary, growth-oriented perspective on governance of software platforms and further detailing platform launch and growth strategies towards a design theory for platform launch. This paper contributes to the understanding of software platforms by reviewing factors driving adoption and triggering network effects

The link between product service lifetime and GHG emissions: A comparative study for different consumer products

The production, use, and final disposal of goods are directly linked to various environmental impacts caused along their supply chains and over their entire life cycles. When assessing these impacts for energy‐consuming products such as consumer electronics, not only the emissions caused during production but also the energy consumption during the use phase need to be taken into account in order to provide a holistic view on environmental impacts. However, the interplay between a product\u27s lifetime, reduction of demand through higher durability, energy consumption, and related greenhouse gas (GHG) emissions cannot be generalized but requires very specific analyses, which take into account product‐related aspects and their temporal changes as well as the (changing) properties of the energy and use system. This contribution provides a quantitative assessment of the interrelation between product lifetime and environmental impacts, particularly GHG emissions, using refrigerators and mobile phones as exemplary products with differing characteristics. Whereas in the case of refrigerators, the strongest impact is caused during the use phase because of high energy consumption and related emissions, mobile phones as representatives of classical consumer electronics have their highest environmental impact during production. To assess impacts for both product categories, two simulation models of product life cycles based on methods from dynamic material flow analysis (MFA) are linked with life cycle inventory (LCI) data and LCA results for the respective products, focusing on the impact category of global warming potential (GWP). By systematically evaluating different scenarios, we show major influences on the overall GHG emissions over a product\u27s lifetime capturing temporal developments and modifications within the target system at European scale. In the case of refrigerators, we show that there is a trend towards increasing optimum lifetimes and that current energy efficiency improvements of new devices do not justify early replacement of older devices and, hence, a reduction of service lifetime. This is also because the GHG emissions of electricity production have continuously decreased with an increasing share of renewable energy sources. Regarding mobile phones, we emphasize the counterproductive effect of unused storage time (hibernation) when taking efforts for increasing the service lifetimes aiming at a reduction of demand for new, resource‐consuming devices

Establishing a lesser kestrel colony in an urban environment for research purposes

[ES] Debido al declive reciente de las poblaciones de Falco naumanni, se han llevado a cabo numerosos proyectos de reintroducción y refuerzo de sus poblaciones en varios países mediterráneos. Aprovechando la experiencia de proyectos previos, intentamos establecer una colonia de F. naumanni en la cubierta de la sede central de la Estación Biológica de Doñana, un edificio moderno y recientemente construido en Sevilla, sur de España. Nuestro objetivo es obtener un acceso fácil a una población urbana y silvestre de esta especie modelo con fines científicos. Después de la liberación de los primeros individuos mediante el método de crianza campestre hace cinco años, nuestra colonia experimental parece haberse establecido. Tres, seis y tres parejas intentaron reproducirse en los años 2010, 2011 y 2012, respectivamente.Peer reviewe

Experimental methods for the analysis of the durability behavior of concrete joints

This article addresses the applicability of experimental methods for the evaluation of concrete durability on localized structural weaknesses posed by joints. Three different types of exposure are analyzed: chloride penetration, carbonation, and freeze–thaw attack. First, established experimental methods for the characterization of the durability of plain concrete are presented and their general applicability on concrete joints is discussed. The experimental program focuses on the execution of selected tests on laboratory specimens with and without joints. Indicator tests for both chloride penetration and carbonation are generally feasible, but require attention to specimen preparation. Rapid chloride migration yielded inconclusive results, while uniaxial chloride diffusion coefficient of concrete joints cannot be determined because of the areal extent of profile grinding. For the same reason, the characterization of the resistance to freeze–thaw cycles through surface deterioration is not applicable for concrete joints. The structural damage was instead successfully qualified through direct tension tests

Experimental methods for the analysis of the tensile behavior of concrete joints

Adhesion plays an important role in the evaluation of hydraulic structures with unreinforced concrete joints. The experimental determination of joint tensile strength as a quantifiable parameter is not standardized, resulting in a variety of test setups found in literature. The present paper highlights advantages and disadvantages of three of the most common tension tests for plain concrete and concrete joints through both theoretical and laboratory experimental analysis on specimens with artificial joints. Splitting tension tests were found to be inexpensive but tend to overestimate the adhesive strength of weak joints. Direct tension tests require an elaborate test setup but may yield information on the tension softening behavior. Pull-off tests stand out for their ability to yield in-situ results but deliver inconclusive results

Elend und Euphorie

Mit Beiträgen von: Hans Ulrich Reck, Julia Scher, Matthias Müller, Dietrich Leder, Marc Pfaff, Joscha Steffens, Konstantin Butz, Georg Trogemann, Gabriele Gramelsberger, Anneka Metzger, Andreas Henric

A unified multiscale modelling approach for concrete fatigue with microscale damage-mechanism implementations

A micro-scale-based for the numerical analysis of cement-based materials, subjected to low- and high-cycle fatigue actions, is presented in this paper

Deletion of the Ca2+-activated potassium (BK) alpha-subunit but not the BK-beta-1-subunit leads to progressive hearing loss

The large conductance voltage- and Ca2+-activated potassium (BK) channel has been suggested to play an important role in the signal transduction process of cochlear inner hair cells. BK channels have been shown to be composed of the pore-forming alpha-subunit coexpressed with the auxiliary beta-1-subunit. Analyzing the hearing function and cochlear phenotype of BK channel alpha-(BKalpha–/–) and beta-1-subunit (BKbeta-1–/–) knockout mice, we demonstrate normal hearing function and cochlear structure of BKbeta-1–/– mice. During the first 4 postnatal weeks also, BKalpha–/– mice most surprisingly did not show any obvious hearing deficits. High-frequency hearing loss developed in BKalpha–/– mice only from ca. 8 weeks postnatally onward and was accompanied by a lack of distortion product otoacoustic emissions, suggesting outer hair cell (OHC) dysfunction. Hearing loss was linked to a loss of the KCNQ4 potassium channel in membranes of OHCs in the basal and midbasal cochlear turn, preceding hair cell degeneration and leading to a similar phenotype as elicited by pharmacologic blockade of KCNQ4 channels. Although the actual link between BK gene deletion, loss of KCNQ4 in OHCs, and OHC degeneration requires further investigation, data already suggest human BK-coding slo1 gene mutation as a susceptibility factor for progressive deafness, similar to KCNQ4 potassium channel mutations. © 2004, The National Academy of Sciences. Freely available online through the PNAS open access option