279 research outputs found
Resolving the productivity paradox of digitalised production
[EN] Although Industry 4.0 and other initiatives predict widespread adoption of digitalised technology on the factory floor, few companies use new digitalised production technology holistically in their ecosystems; in practical implementation, companies often decide against digitalisation for financial reasons. This is due to a paradox (akin to the so called âproductivity paradoxâ) caused by the complexity of value creation and value delivery within digitalised production. This article analyses and synthesises cross-disciplinary research using a grounded theory model, thus offering valuable insights for businesses considering investing in digitalised production. A qualitative model and an associated toolbox (complete with tools for practical application by business leaders and decision-makers) are presented to address organisational uncertainty and leadership disconnect that often contribute to the paradoxical gap between digital strategy and operational implementation.Dold, L.; Speck, C. (2021). Resolving the productivity paradox of digitalised production. International Journal of Production Management and Engineering. 9(2):65-80. https://doi.org/10.4995/ijpme.2021.15058OJS658092Al-Debei, Mutaz M.; Avison, David (2010): Developing a unified framework of the business model concept. In Euro-pean Journal of Information Systems 19 (3), pp. 359-376. https://doi.org/10.1057/ejis.2010.21Andulkar, Mayur; Le, Duc Tho; Berger, Ulrich (2018): A multi-case study on Industry 4.0 for SME's in Brandenburg, Germany. Proceedings of the 51st Hawaii International Conference on System Sciences. Hawaii, 2018. https://doi.org/10.24251/HICSS.2018.574Arnold, Christian; Kiel, Daniel; Voight, Kai-Ingo (2017): Innovative Business Models for the Industrial Internet of Things. In Berg Huettenmaenn Monatsh 162 (9), pp. 371-381. https://doi.org/10.1007/s00501-017-0667-7Arnold, Christian; Voight, Kai-Ingo (2017): Ecosystem Effects of the Industrial Internet of Things on Manufacturing Companies. In Acta INFOLOGICA 1 (2), pp. 99-108.Berghaus, Sabine (2018): The Fuzzy Front End of Digital Transformation. Activities and Approaches for Initiating Organizational Change Strategies. UniversitĂ€t St. Gallen. Available online at https://www1.unisg.ch/www/edis.nsf/SysLkpByIdentifier/4704/$FILE/dis4704.pdf.Berghaus, Sabine; Back, Andrea; Kaltenrieder, Bramwell. (2017): Digital Maturity & Transformation Report 2017. ZĂŒrich: Crosswalk AG,. In Veröffentlichung zur Studie der UniversitĂ€t St. Gallen in Kooperation mit Crosswalk. St. Gallen, March 2017.Bouwman, Harry; Nikou, Shahrokh; Molina-Castillo, Francisco J.; Reuver, Mark de (2018): The impact of digitaliza-tion on business models. In Digital Policy, Regulation and Governance 20 (2), pp. 105-124. https://doi.org/10.1108/DPRG-07-2017-0039Buchholz, Birgit; Ferdinand, Jan-Peter; Gieschen, Jan-Hinrich; Seidel, Uwe (2017): Digitalisierung industrieller Wertschöpfung. Eine Studie im Rahmen der Begleitforschung zum Technologieprogramm AUTONOMIK fĂŒr In-dustrie 4.0 des Bundesministeriums fĂŒr Wirtschaft und Energie. Berlin: iit-Institut fĂŒr Innovation und Technik der VDI/VDE Innovation + Technik GmbH.BurggrĂ€f, Peter; Dannapfel, Matthias; Voet, Hanno; Bök, Patrick-Benjamin; Uelpenich, JĂ©rĂŽme; Hoppe, Julian (2017): Digital Transformation of Lean Production. Systematic Approach for the Determination of Digitally Pervasive Val-ue Chains. In World Academy of Science, Engineering and Technology, International Journal of Social, Behavioral, Educational, Economic, Business and Industrial Engineering 11 (10), 2462-2471.Burmeister, Christian; Luettgens, Dirk; Piller, Frank T. (2016): Business Model Innovation for Industrie 4.0. Why the 'Industrial Internet' Mandates a New Perspective. In Die UnternehmensfĂŒhrung ; RWTH-TIM Working Paper 70 (2), pp. 124-152. https://doi.org/10.2139/ssrn.2571033Cañas, HĂ©ctor; Mula, Josefa; DĂaz-Madroñero, Manuel; Campuzano-BolarĂn, Francisco (2021): Implementing Industry 4.0 principles. In Computers & Industrial Engineering 158 (1), p. 107379. https://doi.org/10.1016/j.cie.2021.107379Charmaz, Kathy (2014): Constructing grounded theory. 2nd edition. Los Angeles, London, New Delhi, Singapore, Washington DC: SAGE.Chesbrough, Henry (2010): Business model innovation: opportunities and barriers. Opportunities and Barriers. 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J Social Sci. 8 (1), pp. 86-95. DOI: 10.21467/ajss.8.1.86-95.Döring, Nicola; Bortz, JĂŒrgen (2016): Forschungsmethoden und Evaluation in den Sozial- und Humanwissenschaften. With assistance of Sandra Pöschl. 5. vollstĂ€ndig ĂŒberarbeitete, aktualisierte und erweiterte Auflage. Berlin, Heidel-berg: Springer (Springer-Lehrbuch). https://doi.org/10.1007/978-3-642-41089-5Dorst, Wolfgang (2016): Implementation Strategy Industrie 4.0. Report on the results of the Industrie 4.0 Platform. With assistance of W. Dorst, C. Glohr, T. Hahn, U. Loewen, Rosen, R. Schiemann, T., F. Vollmar et al. Edited by BITKOM e.V., VDMA e.V., ZVEI e.V. Berlin, Frankfurt am Main.Eruvankai, Saju; Muthukrishnan, Murugesan; Mysore, Anantharamaiah Kumar (2017): Accelerating IIOT Adoption with OPC UA. In INTERNETWORKING INDONESIA 9 (1), pp. 3-8. 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A top-down view on DNA replication and recombination from 9,000 feet above sea level
A report of the Keystone Symposium 'DNA Replication and Recombination' held in Keystone, USA, 27 February to 4 March 2011
Fluctuations and response in a non-equilibrium micron-sized system
The linear response of non-equilibrium systems with Markovian dynamics
satisfies a generalized fluctuation-dissipation relation derived from time
symmetry and antisymmetry properties of the fluctuations. The relation involves
the sum of two correlation functions of the observable of interest: one with
the entropy excess and the second with the excess of dynamical activity with
respect to the unperturbed process, without recourse to anything but the
dynamics of the system. We illustrate this approach in the experimental
determination of the linear response of the potential energy of a Brownian
particle in a toroidal optical trap. The overdamped particle motion is
effectively confined to a circle, undergoing a periodic potential and driven
out of equilibrium by a non-conservative force. Independent direct and indirect
measurements of the linear response around a non-equilibrium steady state are
performed in this simple experimental system. The same ideas are applicable to
the measurement of the response of more general non-equilibrium micron-sized
systems immersed in Newtonian fluids either in stationary or non-stationary
states and possibly including inertial degrees of freedom.Comment: 12 pages, submitted to J. Stat. Mech., revised versio
The ORC/Cdc6/MCM2-7 complex facilitates MCM2-7 dimerization during prereplicative complex formation.
The replicative mini-chromosome-maintenance 2-7 (MCM2-7) helicase is loaded in Saccharomyces cerevisiae and other eukaryotes as a head-to-head double-hexamer around origin DNA. At first, ORC/Cdc6 recruits with the help of Cdt1 a single MCM2-7 hexamer to form an 'initial' ORC/Cdc6/Cdt1/MCM2-7 complex. Then, on ATP hydrolysis and Cdt1 release, the 'initial' complex is transformed into an ORC/Cdc6/MCM2-7 (OCM) complex. However, it remains unclear how the OCM is subsequently converted into a MCM2-7 double-hexamer. Through analysis of MCM2-7 hexamer-interface mutants we discovered a complex competent for MCM2-7 dimerization. We demonstrate that these MCM2-7 mutants arrest during prereplicative complex (pre-RC) assembly after OCM formation, but before MCM2-7 double-hexamer assembly. Remarkably, only the OCM complex, but not the 'initial' ORC/Cdc6/Cdt1/MCM2-7 complex, is competent for MCM2-7 dimerization. The MCM2-7 dimer, in contrast to the MCM2-7 double-hexamer, interacts with ORC/Cdc6 and is salt-sensitive, classifying the arrested complex as a helicase-loading intermediate. Accordingly, we found that overexpression of the mutants cause cell-cycle arrest and dominant lethality. Our work identifies the OCM complex as competent for MCM2-7 dimerization, reveals MCM2-7 dimerization as a limiting step during pre-RC formation and defines critical mechanisms that explain how origins are licensed
Decentralized Open Platform for VaccinationâA German Example: COVID-19-Vacc
The COVID-19 pandemic has massively impacted the health of many people worldwide and poses significant challenges for our social, economic, and political life. Global vaccination should help the world overcome the pandemic and return to a ânormalâ life. In Germany, the Federal Ministry of Health presented its âNational Vaccination Strategy COVID-19â, which describes the primary actors, elements, and activities required for the immunization of the German population. However, the implementation is challenging due to the federal organization of the German state in sixteen federal states. While essential processes such as vaccination rate monitoring and surveillance are planned centrally, the sixteen federal states are responsible for implementing the vaccination strategy in a decentralized manner. Furthermore, the European General Data Protection Regulation (EU-GDPR) imposes strict rules for processing and exchanging personal data. However, Germany is only a case in point. Governmental decisions always need to be implemented by regional and/or local actors, the number of which varies greatly depending on the country. This work addresses these challenges by proposing the COVID-19-Vacc Platformâan open and decentralized digital platform focused on vaccinations as a matter of example. The proposed platform model connects various actors and enables them to involve, conduct, and track the vaccination process while meeting all necessary data protection and security requirements defined by EU-GDPR. Using the DMS Reference Model as the theoretical framework, the blueprint of the COVID-19-Vacc Platform is developed, outlining the platformâs ecosystem structure, its interactions process model, and the service stack, defining how the proposed platform works on the operational level. Our COVID-19-Vacc Platform may help facilitate a fast and EU-GDPR compliant implementation of COVID-19 vaccination strategies. Beyond that, the proposed open and decentralized platform model might facilitate international interconnectivity and therefore the management of emerging global pandemics or other global health-related crisi
Fabrication technology for high light-extraction ultraviolet thin-film flip-chip (UV TFFC) LEDs grown on SiC
The light output of deep ultraviolet (UV-C) AlGaN light-emitting diodes
(LEDs) is limited due to their poor light extraction efficiency (LEE). To
improve the LEE of AlGaN LEDs, we developed a fabrication technology to process
AlGaN LEDs grown on SiC into thin-film flip-chip LEDs (TFFC LEDs) with high
LEE. This process transfers the AlGaN LED epi onto a new substrate by
wafer-to-wafer bonding, and by removing the absorbing SiC substrate with a
highly selective SF6 plasma etch that stops at the AlN buffer layer. We
optimized the inductively coupled plasma (ICP) SF6 etch parameters to develop a
substrate-removal process with high reliability and precise epitaxial control,
without creating micromasking defects or degrading the health of the plasma
etching system. The SiC etch rate by SF6 plasma was ~46 \mu m/hr at a high RF
bias (400 W), and ~7 \mu m/hr at a low RF bias (49 W) with very high etch
selectivity between SiC and AlN. The high SF6 etch selectivity between SiC and
AlN was essential for removing the SiC substrate and exposing a pristine,
smooth AlN surface. We demonstrated the epi-transfer process by fabricating
high light extraction TFFC LEDs from AlGaN LEDs grown on SiC. To further
enhance the light extraction, the exposed N-face AlN was anisotropically etched
in dilute KOH. The LEE of the AlGaN LED improved by ~3X after KOH roughening at
room temperature. This AlGaN TFFC LED process establishes a viable path to high
external quantum efficiency (EQE) and power conversion efficiency (PCE) UV-C
LEDs.Comment: 22 pages, 6 figures. (accepted in Semiconductor Science and
Technology, SST-105156.R1 2018
Seal Rotation Device â an Automated System for documenting Cylinder Seals
Cylinder seals are complex artifacts used in many early administrative systems especially in the Near East and Egypt. They are also linked to religious practices and concepts of identity. Several classical methods can be applied to document these objects, like photography, drawing and molding in plaster or plasticine. In addition to more recent methods like structured light scanning, we present an alternative method for 3D data acquisition. By combining existing technologies in a particular way, seals can be documented fast, cost efficiently and safe from a conservation viewpoint. This method developed at the Interdisciplinary Center for Scientific Computing (IWR) at Heidelberg University is a two-step procedure: first several series of images are obtained with a digital reflex camera in an automated way. The seal is mounted between two soft silicone buffers. An Arduino-based control unit rotates the seal using a stepper motor and triggers the camera. In the second step a 3D reconstruction of the seal is computed with the photogrammetric structure-from-motion approach. We will show first results acquired with this method both at the Petrie Museum of Egyptian Archaeology and the British Museum in London
A conformal approach for the analysis of the non-linear stability of pure radiation cosmologies
The conformal Einstein equations for a tracefree (radiation) perfect fluid
are derived in terms of the Levi-Civita connection of a conformally rescaled
metric. These equations are used to provide a non-linear stability result for
de Sitter-like tracefree (radiation) perfect fluid
Friedman-Lema\^{\i}tre-Robertson-Walker cosmological models. The solutions thus
obtained exist globally towards the future and are future geodesically
complete.Comment: 21 page
The structure of ORCâCdc6 on an origin DNA reveals the mechanism of ORC activation by the replication initiator Cdc6
The Origin Recognition Complex (ORC) binds to sites in chromosomes to specify the location of origins of DNA replication. The S. cerevisiae ORC binds to specific DNA sequences throughout the cell cycle but becomes active only when it binds to the replication initiator Cdc6. It has been unclear at the molecular level how Cdc6 activates ORC, converting it to an active recruiter of the Mcm2-7 hexamer, the core of the replicative helicase. Here we report the cryo-EM structure at 3.3âĂ
resolution of the yeast ORCâCdc6 bound to an 85-bp ARS1 origin DNA. The structure reveals that Cdc6 contributes to origin DNA recognition via its winged helix domain (WHD) and its initiator-specific motif. Cdc6 binding rearranges a short α-helix in the Orc1 AAA+ domain and the Orc2 WHD, leading to the activation of the Cdc6 ATPase and the formation of the three sites for the recruitment of Mcm2-7, none of which are present in ORC alone. The results illuminate the molecular mechanism of a critical biochemical step in the licensing of eukaryotic replication origins
- âŠ