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In several organizations, business workgroups autonomously implement information technology (IT) outside the purview of the IT department. Shadow IT, evolving as a type of workaround from nontransparent and unapproved end-user computing (EUC), is a term used to refer to this phenomenon, which challenges norms relative to IT controllability. This report describes shadow IT based on case studies of three companies and investigates its management. In 62% of cases, companies decided to reengineer detected instances or reallocate related subtasks to their IT department. Considerations of risks and transaction cost economics with regard to specificity, uncertainty, and scope explain these actions and the resulting coordination of IT responsibilities between the business workgroups and IT departments. This turns shadow IT into controlled business-managed IT activities and enhances EUC management. The results contribute to the governance of IT task responsibilities and provide a way to formalize the role of workarounds in business workgroups.
Traditional Western philosophy, cognitive science and traditional HCI frameworks approach the term digital and its implications with an implicit dualism (nature/cul-ture, theory /practice, body/mind, human/machine). What lies between is a feature of our postmodern times, in which different states, conditions or positions merge and co-exist in a new, hybrid reality, a “continuous beta” (Mühlenbeck & Skibicki, 2007) version of becoming .Post-digitality involves the physical dimensions of spatio-temporal engagements. This new ontological paradigm reconceptualizes digital technology through the ex-perience of the human body and its senses, thus emphasizing form-taking, situation-al engagement and practice rather than symbolic, disembodied rationality. This rais-es two questions in particular: how to encourage curiosity, playfulness, serendipity, emergence, discourse and collectivity? How to construct working methods without foregrounding and dividing the subject into an individual that already takes posi-tion? This paper briefly outlines the rhizomatic framework that I developed within my PhD research. This attempts to overcome two prevailing tendencies: first, the one-sided view of scientific approaches to knowledge acquisition and the pure-ly application-oriented handling of materials, technologies and machines; second, the distanced perception of the world. In contrast, my work involves project-driven alchemic curiosity and doing research through artistic design practice. This means thinking through materials, technologies and machinic interactions. Now, at the end of this PhD journey, 10 interdisciplinary projects have emerged from this ontological queer-paradigm that is post-digital–crafting 4.0. Below I illustrate this approach and its outcomes.
The actual task of electrocardiographic examinations is to increase the reliability of diagnosing the condition of the heart. Within the framework of this task, an important direction is the solution of the inverse problem of electrocardiography, based on the processing of electrocardiographic signals of multichannel cardio leads at known electrode coordinates in these leads (Titomir et al. Noninvasiv electrocardiotopography, 2003), (Macfarlane et al. Comprehensive Electrocardiology, 2nd ed. (Chapter 9), 2011).
Infolge des Klimawandels sind entlang der Gewässer Baden-Württembergs verschärfte Niedrigwassersituationen zu erwarten, die unter Umständen zu Wassernutzungskonflikten der lokalen Akteure führen. Anhand des Kochers und der Murg wurden mit Hilfe einer Stakeholder-Analyse solche Konflikte identifiziert sowie erste Handlungsoptionen für eine Niedrigwasservorsorge bzw. ein Niedrigwassermanagement erarbeitet. Den Erhebungen zufolge treten Wassernutzungskonkurrenzen in fast allen Nutzergruppen auf, jedoch mit unterschiedlicher Ausprägung. Hierbei stehen bestimmte Sektoren teilweise mit mehreren Stakeholder-Gruppen im Widerstreit, andere Gruppen haben dagegen keine Erfahrung mit Konkurrenzsituationen. Weiterhin ist auffällig, dass Niedrigwasserereignisse an beiden Flüssen lediglich einen Teil der Nutzungskonflikte auslösen. Ein Großteil der Streitfragen wird durch anthropogene Einflüsse verursacht.
Im vorliegenden Aufsatz werden die rechnerischen Rissbreiten bei frühem und bei spätem Zwang verglichen. Insbesondere wird der Fall betrachtet, dass nach einer frühen Rissbildung infolge Abfließens der Hydratationswärme im fortgeschrittenen Betonalter Zwängungen durch Schwinden und/oder Temperatureinflüsse entstehen. Es wird gezeigt, dass die im jungen Betonalter entstandenen Risse zunächst breiter werden, bevor neue Risse infolge späten Zwangs entstehen können, und dass die resultierende Rissbreite dann größer ist, als wenn die Risse ausschließlich durch späten Zwang entstehen. Für die rechnerische Behandlung dieser Problematik wird ein einfaches Rechenverfahren aufgezeigt. Des Weiteren wird auf die Konzentration von zwangsbedingten Rissen in Schwachstellen, z. B. bei Bodenplatten und Decken mit großen Aussparungen, eingegangen und es wird dargestellt, wie für solche Bauteilgeometrien die rechnerische Begrenzung der Rissbreite erfolgen kann.
Üblicherweise wird bei der Erdbebenbemessung von durch Stahlbetonwände ausgesteiften Gebäuden entweder die ungerissene Biegesteifigkeit oder ein von dieser durch einen Abminderungsfaktor abgeleiteter Wert zur Berücksichtigung des Zustands II verwendet. Tatsächlich ist die Biegesteifigkeit von Stahlbetonquerschnitten jedoch vom Bewehrungsgrad und von der Normalkraft abhängig. Die Fließverschiebung, bei der sich am Fuß einer Stahlbetonwand ein plastisches Gelenk bildet, ist hingegen fast ausschließlich von ihrer Länge im Grundriss abhängig. Torsionswirkungen infolge Exzentrizität zwischen Massen- und Steifigkeitsmittelpunkt werden üblicherweise durch Vergrößerung der Bemessungskräfte der einzelnen Wände berücksichtigt. Den durch die Torsionswirkung vergrößerten Verschiebungen einzelner Wände wird dabei keine Beachtung geschenkt. Da die durch die Verhaltensbeiwerte der Normen implizit vorausgesetzte ertragbare Verformung des Tragsystems zusätzliche Verschiebungen infolge Torsion nicht explizit berücksichtigt, kann es so unter Umständen wegen Überschreitung der maximal möglichen Verformung einzelner Wände zu einem vorzeitigen Versagen kommen. Im vorliegenden Aufsatz wird ein quasi-händisches Nachweisverfahren vorgestellt, mit dem die explizite Berücksichtigung von torsionsbedingten Verschiebungen möglich ist und bei dem realistische Biegesteifigkeiten für die Wände verwendet werden.
In [Zahn, F., Köber, D., Verfahren zum Erdbebennachweis von durch Stahlbetonwände ausgesteiften Gebäuden mit explizitem Nachweis der Verformungen. Beton- und Stahlbetonbau 110 (2015) Heft 4, S. 293–302] wird ein Bemessungsverfahren für durch Erdbeben beanspruchte Tragwerke vorgestellt, mit dem die explizite Berücksichtigung von torsionsbedingten Verschiebungen möglich ist und bei dem realistische Biegesteifigkeiten für die Wände verwendet werden. Da mit diesem vereinfachten Verfahren mit vertretbarem Aufwand nur der getrennte Tragsicherheitsnachweis für Erdbebenbeanspruchungen in den Gebäudehauptrichtungen möglich ist, wird in diesem Aufsatz der Frage nachgegangen, ob ein Gebäude, für welches der Nachweis in beiden Hauptrichtungen erbracht wird, auch für Erdbebenbeanspruchung unter 45° zu den Hauptrichtungen ausreichende Standsicherheit besitzt. Zu diesem Zwecke werden zwei Beispielgebäude zunächst mit dem in [1] beschriebenen Verfahren auf ihre Standsicherheit in den Hauptrichtungen untersucht und anschließend mit dem Programm ETABS nachgerechnet, und zwar zunächst jeweils in einer Gebäudehauptrichtung und danach für eine Beanspruchung unter 45° zu dieser.
Im vorliegenden Beitrag wird der Einfluss der Modellierung des Kellergeschosses auf die Querkraft und die Verformungen von im Kellergeschoss eingespannten Stahlbeton‐Aussteifungswänden untersucht. Der Querkraftverlauf der Wand und die Verschiebung am Kopf der Wand werden mit den entsprechenden, am vereinfachten Kragwandmodell ermittelten Werten verglichen, bei dem die Wand auf Höhe der Kellerdecke voll eingespannt ist und die Weiterleitung der Schnittkräfte im Kellergeschoss nicht näher betrachtet wird. Für die Berücksichtigung des Kellergeschosses wird zunächst eine gelenkige Festhaltung durch die Kellerdecke und die Bodenplatte betrachtet, wodurch sich eine unrealistisch große Wandquerkraft im Kellergeschoss ergibt. Danach wird ein verfeinertes Modell mit Teileinspannung in der Bodenplatte und nachgiebiger Halterung durch die Kellerdecke untersucht. Es werden Empfehlungswerte für die Federkonstante der Drehfeder auf Höhe der Bodenplatte und der horizontalen Translationsfeder auf Höhe der Kellerdecke angegeben, die in der Praxis Anwendung finden können. Es wird besonders der Frage nachgegangen, welche Einflüsse die Berücksichtigung des Kellergeschosses bei der Erdbebenbemessung der Aussteifungswände hat. Dabei wird einerseits die Systemsteifigkeit, von der die Erdbebenersatzlasten abhängen, und andererseits die mögliche Verschiebungsduktilität, von der der mögliche Verhaltensbeiwert q abhängt, betrachtet.
Sanktionen stellen Zwangsmaßnahmen dar, die bei der Bewältigung politischer Spannungen zwischen Nationen eine lange und wiederkehrende Stellung einnehmen. Sie werden sowohl einseitig als auch in Staatenbündnissen verhängt und besonders nach dem 2. Weltkrieg mit zunehmender Häufigkeit eingesetzt. Während im letzten Jahrhundert, insbesondere vor dem 2. Weltkrieg, Handelsbeschränkungen und umfassende Wirtschaftsblockaden die vorherrschenden Sanktionsinstrumente darstellten, werden heute in einer stärker integrierten und globalisierten Welt Sanktionen in verschiedenen weiteren Formen verhängt, einschließlich internationaler Finanzbeschränkungen, Reiseverbote, Handelseinschränkungen für bestimmte Gütergruppen, Aufhebung militärischer Hilfen und spezifische Einschränkungen, wie beispielsweise Flugverbote und Hafensperrungen.
Many countries offer state credit guarantees to support credit-constrained exporters. The policy instrument is commonly justified by governments as a means to mitigating adverse outcomes of financial market frictions for exporting firms. Accumulated returns to the German state credit guarantee scheme deriving from risk-compensating premia have outweighed accumulated losses over the past 60 years. Why do private financial agents not step in and provide insurance given that the state-run program yields positive returns? We argue that costs of risk diversification, liquidity management, and coordination among creditors limit the ability of private financial agents to offer comparable insurance products. Moreover, we suggest that the government’s greater effectiveness in recovering claims in foreign countries endows the state with a cost advantage in dealing with the risks involved in large export projects. We test these hypotheses using monthly firm-level data combined with official transaction-level data on covered exports of German firms and find suggestive evidence that positive effects on trade are due to mitigated financial constraints: State credit guarantees benefit firms that are dependent on external finance, if the value at risk which they seek to cover is large, and at times when refinancing conditions on the private financial market are tight.
This article introduces the Global Sanctions Data Base (GSDB), a new dataset of economic sanctions that covers all bilateral, multilateral, and plurilateral sanctions in the world during the 1950–2016 period across three dimensions: type, political objective, and extent of success. The GSDB features by far the most cases amongst data bases that focus on effective sanctions (i.e., excluding threats) and is particularly useful for analysis of bilateral international transactional data (such as trade flows). We highlight five important stylized facts: (i) sanctions are increasingly used over time; (ii) European countries are the most frequent users and African countries the most frequent targets; (iii) sanctions are becoming more diverse, with the share of trade sanctions falling and that of financial or travel sanctions rising; (iv) the main objectives of sanctions are increasingly related to democracy or human rights; (v) the success rate of sanctions has gone up until 1995 and fallen since then. Using state-of-the-art gravity modeling, we highlight the usefulness of the GSDB in the realm of international trade. Trade sanctions have a negative but heterogeneous effect on trade, which is most pronounced for complete bilateral sanctions, followed by complete export sanctions.
Multi-faceted stresses of social, environmental, and economic nature are increasingly challenging the existence and sustainability of our societies. Cities in particular are disproportionately threatened by global issues such as climate change, urbanization, population growth, air pollution, etc. In addition, urban space is often too limited to effectively develop sustainable, nature-based solutions while accommodating growing populations. This research aims to provide new methodologies by proposing lightweight green bridges in inner-city areas as an effective land value capture mechanism. Geometry analysis was performed using geospatial and remote sensing data to provide geometrically feasible locations of green bridges. A multi-criteria decision analysis was applied to identify suitable locations for green bridges investigating Central European urban centers with a focus on German cities as representative examples. A cost-benefit analysis was performed to assess the economic feasibility using a case study. The results of the geometry analysis identified 3249 locations that were geometrically feasible to implement a green bridge in German cities. The sample locations from the geometry analysis were proved to be validated for their implementation potential. Multi-criteria decision analysis was used to select 287 sites that fall under the highest suitable class based on several criteria. The cost-benefit analysis of the case study showed that the market value of the property alone can easily outweigh the capital and maintenance costs of a green bridge, while the indirect (monetary) benefits of the green space continue to increase the overall value of the green bridge property including its neighborhood over time. Hence, we strongly recommend light green bridges as financially sustainable and nature-based solutions in cities worldwide.
Im vorliegenden Aufsatz wird das grundlegende Vorgehen zur Berechnung der Durchbiegung im gerissenen Zustand inklusive Berücksichtigung von Kriechen und Schwinden vorgestellt. Dabei werden aufbauend auf den Vorgaben des EC2 verschiedene Verfahren mit unterschiedlichen Genauigkeitsniveaus für Balken und einachsig gespannte Platten erläutert. Für einfache Systeme können diese Verfahren auch von Hand durchgeführt werden und bieten dabei ein hohes Maß an Kontrolle über den Rechenablauf. Anschließend wird die Ermittlung der Schwindverformungen genauer betrachtet, welche nur mit hohem Rechenaufwand durchgeführt werden kann. Für eine Auswahl von Systemen können Diagramme mit Multiplikationsfaktoren hergeleitet werden, welche die Berechnung stark vereinfachen. Des Weiteren wird auf die Verformungsberechnung im Zustand II für Plattentragwerke eingegangen. Dabei werden sowohl die Berechnung mit FE‐Plattenprogrammen, welche oftmals entsprechende Funktionen anbieten, als auch vereinfachte manuelle Verfahren vorgestellt. Die Grundlagen der Rissbildung lassen sich von Stabtragwerken auf Platten übertragen, allerdings entstehen dabei neue Fragestellungen, wie beispielsweise zum Vorgehen bei der Steifigkeitsabminderung oder zum Einfluss der Schnittgrößenumlagerung infolge Rissbildung. In diesem Bereich besteht daher noch Forschungsbedarf.
In Ganglaboren werden medizinische Gang- und Laufanalysen durchgeführt. Eine in eine Decke eingelassene Kraftmessplatte ermöglicht dabei die präzise Messung der vom Menschen auf den Boden übertragenen Kräfte. Die Beschleunigungen der Decke, in die die Kraftmessplatte eingelassen ist, müssen begrenzt werden, damit die Messgenauigkeit der Kraftmessplatte nicht beeinträchtigt wird.
Für das wissenschaftliche Ganglabor im Neubau des Medizinischen Trainings- und Rehabilitationszentrums an der Universitätsklinik Tübingen wurde untersucht, inwieweit die Messgenauigkeit einer Kraftmessplatte durch personeninduzierte Deckenschwingungen beeinflusst wird. Als Ergebnis kann der Messfehler in Abhängigkeit von der Masse des Probanden im Ganglabor bei unterschiedlichen Szenarien angegeben werden.
“Crowd contamination”?
(2023)
Misconduct allegations have been found to not only affect the alleged firm but also other, unalleged firms in form of reputational and financial spillover effects. It has remained unexplored, however, how the number of prior allegations against other firms matters for an individual firm currently facing an allegation. Building on behavioral decision theory, we argue that the relationship between allegation prevalence among other firms and investor reaction to a focal allegation is inverted U-shaped. The inverted U-shaped effect is theorized to emerge from the combination of two effects: In the absence of prior allegations against other firms, investors fail to anticipate the focal allegation, and hence react particularly negatively (“anticipation effect”). In the case of many prior allegations against other firms, investors also react particularly negatively because investors perceive the focal allegation as more warranted (“evaluation effect”). The multi-industry, empirical analysis of 8,802 misconduct allegations against US firms between 2007 and 2017 provides support for our predicted, inverted U-shaped effect. Our study complements recent misconduct research on spillover effects by highlighting that not only a current allegation against an individual firm can “contaminate” other, unalleged firms but that also prior allegations against other firms can “contaminate” investor reaction to a focal allegation against an individual firm.
Cities around the world are facing the implications of a changing climate as an increasingly pressing issue. The negative effects of climate change are already being felt today. Therefore, adaptation to these changes is a mission that every city must master. Leading practices worldwide demonstrate various urban efforts on climate change adaptation (CCA) which are already underway. Above all, the integration of climate data, remote sensing, and in situ data is key to a successful and measurable adaptation strategy. Furthermore, these data can act as a timely decision support tool for municipalities to develop an adaptation strategy, decide which actions to prioritize, and gain the necessary buy-in from local policymakers. The implementation of agile data workflows can facilitate the integration of climate data into climate-resilient urban planning. Due to local specificities, (supra)national, regional, and municipal policies and (by) laws, as well as geographic and related climatic differences worldwide, there is no single path to climate-resilient urban planning. Agile data workflows can support interdepartmental collaboration and, therefore, need to be integrated into existing management processes and government structures. Agile management, which has its origins in software development, can be a way to break down traditional management practices, such as static waterfall models and sluggish stage-gate processes, and enable an increased level of flexibility and agility required when urgent. This paper presents the findings of an empirical case study conducted in cooperation with the City of Constance in southern Germany, which is pursuing a transdisciplinary and trans-sectoral co-development approach to make management processes more agile in the context of climate change adaptation. The aim is to present a possible way of integrating climate data into CCA planning by changing the management approach and implementing a toolbox for low-threshold access to climate data. The city administration, in collaboration with the University of Applied Sciences Constance, the Climate Service Center Germany (GERICS), and the University of Stuttgart, developed a co-creative and participatory project, CoKLIMAx, with the objective of integrating climate data into administrative processes in the form of a toolbox. One key element of CoKLIMAx is the involvement of the population, the city administration, and political decision-makers through targeted communication and regular feedback loops among all involved departments and stakeholder groups. Based on the results of a survey of 72 administrative staff members and a literature review on agile management in municipalities and city administrations, recommendations on a workflow and communication structure for cross-departmental strategies for resilient urban planning in the City of Constance were developed.
Healthy and good sleep is a prerequisite for a rested mind and body. Both form the basis for physical and mental health. Healthy sleep is hindered by sleep disorders, the medically diagnosed frequency of which increases sharply from the age of 40. This chapter describes the formal specification of an on-course practical implementation for a non-invasive system based on biomedical signal processing to support the diagnosis and treatment of sleep-related diseases. The system aims to continuously monitor vital data during sleep in a patient’s home environment over long periods by using non-invasive technologies. At the center of the development is the MORPHEUS Box (MoBo), which consists of five main conceptualizations: the MoBo core, the MoBo-HW, the MoBo algorithm, the MoBo API, and the MoBo app. These synergistic elements aim to support the diagnosis and treatment of sleep-related diseases. Although there are related developments in individual aspects concerning the system, no comparative approach is known that gives a similar scope of functionality, deployment flexibility, extensibility, or the possibility to use multiple user groups. With the specification provided in this chapter, the MORPHEUS project sets a good platform, data model, and transmission strategies to bring an innovative proposal to measure sleep quality and detect sleep diseases from non-invasive sensors.
Das Software-Engineering sollte nicht nur über das Aufzählen von Aktivitäten charakterisiert, sondern zusätzlich auch über grundsätzliche Probleme motiviert werden. Die Beschäftigung mit dem Warum des Software-Engineerings erhält so mehr Gewicht gegenüber dem Wie. Mit der Betonung des Problembewusstseins nährt man auch weniger das Missverständnis, das Software-Engineering diene hauptsächlich der Disziplinierung von Software- Entwicklern. Es geht eben nicht in erster Linie darum, sich in ein Vorgehensmodell einzufügen und eine Aktivität nach der anderen regelkonform mit den vorgesehenen Werkzeugen abzuarbeiten. Vielmehr sind Spürsinn, Kreativität und Urteilsvermögen gefragt. Denn die genannten grundsätzlichen Probleme sind zwar in jedem Projekt allgegenwärtig, aber trotzdem nicht unbedingt auf den ersten Blick erkennbar, und sie müssen mangels echter Lösungen immer neu mit angemessenen Kompromissen bewältigt werden. Dabei ist Nützlichkeit der Maßstab, nicht Wahrheit. Das alles ist herausfordernd und Herausforderungen machen Spaß.
This paper compares two popular scripting implementations for hardware prototyping: Python scripts exe- cut from User-Space and C-based Linux-Driver processes executed from Kernel-Space, which can provide information to researchers when considering one or another in their implementations. Conclusions exhibit that deploying software scripts in the kernel space makes it possible to grant a certain quality of sensor information using a Raspberry Pi without the need for advanced real-time operational systems.
A nonlinear mathematical model for the dynamics of permanent magnet synchronous machines with interior magnets is discussed. The model of the current dynamics captures saturation and dependency on the rotor angle. Based on the model, a flatness-based field-oriented closed-loop controller and a feed-forward compensation of torque ripples are derived. Effectiveness and robustness of the proposed algorithms are demonstrated by simulation results.
We have introduced in this paper new variants of two methods for projecting Supply and Use Tables that are based on a distance minimisation approach (SUT-RAS) and the Leontief model (SUT-EURO). We have also compared them under similar and comparable exogenous information, i.e.: with and without exogenous industry output, and with explicit consideration of taxes less subsidies on products. We have conducted an empirical assessment of all of these methods against a set of annual tables between 2000 and 2005 for Austria, Belgium, Spain and Italy. From the empirical assessment, we obtained three main conclusions: (a) the use of extra information (i.e. industry output) generally improves projected estimates in both methods; (b) whenever industry output is available, the SUT-RAS method should be used and otherwise the SUT-EURO should be used instead; and (c) the total industry output is best estimated by the SUT-EURO method when this is not available.
The main objective of this paper is to revisit the Euro method in a critical and constructive way.Wehave analysed some arguments against the Euro method published recently in the literature as well as some other relevant aspects of the SUT-Euro and SUT-RAS methods not covered before. Although not being the Euro method perfect, we believe that there is still space for the use of the Euro method in updating/regionalizing Supply and Use tables.
Software startups
(2016)
Software startup companies develop innovative, software-intensive products within limited time frames and with few resources, searching for sustainable and scalable business models. Software startups are quite distinct from traditional mature software companies, but also from micro-, small-, and medium-sized enterprises, introducing new challenges relevant for software engineering research. This paper’s research agenda focuses on software engineering in startups, identifying, in particular, 70+ research questions in the areas of supporting startup engineering activities, startup evolution models and patterns, ecosystems and innovation hubs, human aspects in software startups, applying startup concepts in non-startup environments, and methodologies and theories for startup research. We connect and motivate this research agenda with past studies in software startup research, while pointing out possible future directions. While all authors of this research agenda have their main background in Software Engineering or Computer Science, their interest in software startups broadens the perspective to the challenges, but also to the opportunities that emerge from multi-disciplinary research. Our audience is therefore primarily software engineering researchers, even though we aim at stimulating collaborations and research that crosses disciplinary boundaries. We believe that with this research agenda we cover a wide spectrum of the software startup industry current needs.
Despite the increased attention dedicated to research on the antecedents and determinants of new venture survival in entrepreneurship, defining and capturing survival as an outcome represents a challenge in quantitative studies. This paper creates awareness for ventures being inactive while still classified as surviving based on the data available. We describe this as the ‘living dead’ phenomenon, arguing that it yields potential effects on the empirical results of survival studies. Based on a systematic literature review, we find that this issue of inactivity has not been sufficiently considered in previous new venture survival studies. Based on a sample of 501 New Technology-Based Firms, we empirically illustrate that the classification of living dead ventures into either survived or failed can impact the factors determining survival. On this basis, we contribute to an understanding of the issue by defining the ‘living dead’ phenomenon and by proposing recommendations for research practice to solve this issue in survival studies, taking the data source, the period under investigation and the sample size into account.
This paper builds upon the widely-used resource-based approach to explaining survival of new technology-based firms (NTBFs). However, instead of looking at the NTBF's initial resource configuration, a process-oriented perspective is taken by focusing on the entrepreneur's ability to transform resources in response to triggers resulting from market interactions. Transaction relations reflect these interactions and are thus operationalized with a suggested method for measuring the status of venture emergence (VE) applicable to early-stage NTBFs. NTBFs' value network maturity is reflected in the number and strength of their transaction relations in the four market dimensions customer, investor, partner, and human resource. Business plans of NTBFs represent the artifact that contains this data in the form of transaction relation descriptions. Using content analysis, a multi-step combined human and computer coding process has been developed to annotate and classify transaction relations from business plans in order to empirically determine NTBFs' status of VE. Results of the business plan analysis suggest that the level of transaction relations allows to draw conclusions on the VE status. Moreover, applying the developed process, first analysis of a business plan coding test shows that the transaction relation based VE status significantly relates to NTBF survival capability.
In this article, we give the construction of new four-dimensional signal constellations in the Euclidean space, which represent a certain combination of binary frequency-shift keying (BFSK) and M-ary amplitude-phase-shift keying (MAPSK). Description of such signals and the formulas for calculating the minimum squared Euclidean distance are presented. We have developed an analytic building method for even and odd values of M. Hence, no computer search and no heuristic methods are required. The new optimized BFSK-MAPSK (M = 5,6,···,16) signal constructions are built for the values of modulation indexes h =0.1,0.15,···,0.5 and their parameters are given. The results of computer simulations are also provided. Based on the obtained results we can conclude, that BFSK-MAPSK systems outperform similar four-dimensional systems both in terms of minimum squared Euclidean distance and simulated symbol error rate.
In this letter, we present an approach to building a new generalized multistream spatial modulation system (GMSM), where the information is conveyed by the two active antennas with signal indices and using all possible active antenna combinations. The signal constellations associated with these antennas may have different sizes. In addition, four-dimensional hybrid frequency-phase modulated signals are utilized in GMSM. Examples of GMSM systems are given and computer simulation results are presented for transmission over Rayleigh and deep Nakagami- m flat-fading channels when maximum-likelihood detection is used. The presented results indicate a significant improvement of characteristics compared to the best-known similar systems.
Production and marketing of cereal grains are some of the main activities in developing countries to ensure food security. However, the food gap is complicated further by high postharvest loss of grains during storage. This study aimed to compare low‐cost modified‐atmosphere hermetic storage structures with traditional practice to minimize quantitative and qualitative losses of grains during storage. The study was conducted in two phases: in the first phase, seven hermetic storage structures with or without smoke infusion were compared, and one selected structure was further validated at scaled‐up capacity in the second phase.
Bernstein polynomials on a simplex V are considered. The expansion of a given polynomial p into these polynomials provides bounds for range of p over V. Bounds for the range of a rational function over V can easily be obtained from the Bernstein expansions of the numerator and denominator polynomials of this function. In this paper it is shown that these bounds converge monotonically and linearly to the range of the rational function if the degree of the Bernstein expansion is elevated. If V is subdivided then the convergence is quadratic with respect to the maximum of the diameters of the subsimplices.
Matrix methods for the computation of bounds for the range of a complex polynomial and its modulus over a rectangular region in the complex plane are presented. The approach relies on the expansion of the given polynomial into Bernstein polynomials. The results are extended to multivariate complex polynomials and rational functions.
Tests for speeding up the determination of the Bernstein enclosure of the range of a multivariate polynomial and a rational function over a box and a simplex are presented. In the polynomial case, this enclosure is the interval spanned by the minimum and the maximum of the Bernstein coefficients which are the coefficients of the polynomial with respect to the tensorial or simplicial Bernstein basis. The methods exploit monotonicity properties of the Bernstein coefficients of monomials as well as a recently developed matrix method for the computation of the Bernstein coefficients of a polynomial over a box.
In this paper, multivariate polynomials in the Bernstein basis over a simplex (simplicial Bernstein representation) are considered. Two matrix methods for the computation of the polynomial coefficients with respect to the Bernstein basis, the so-called Bernstein coefficients, are presented. Also matrix methods for the calculation of the Bernstein coefficients over subsimplices generated by subdivision of the standard simplex are proposed and compared with the use of the de Casteljau algorithm. The evaluation of a multivariate polynomial in the power and in the Bernstein basis is considered as well. All the methods solely use matrix operations such as multiplication, transposition, and reshaping; some of them rely also on the bidiagonal factorization of the lower triangular Pascal matrix or the factorization of this matrix by a Toeplitz matrix. The latter one enables the use of the Fast Fourier Transform hereby reducing the amount of arithmetic operations.
In this paper, multivariate polynomials in the Bernstein basis over a box (tensorial Bernstein representation) are considered. A new matrix method for the computation of the polynomial coefficients with respect to the Bernstein basis, the so-called Bernstein coefficients, is presented and compared with existing methods. Also matrix methods for the calculation of the Bernstein coefficients over subboxes generated by subdivision of the original box are proposed. All the methods solely use matrix operations such as multiplication, transposition and reshaping; some of them rely on the bidiagonal factorization of the lower triangular Pascal matrix or the factorization of this matrix by a Toeplitz matrix. In the case that the coefficients of the polynomial are due to uncertainties and can be represented in the form of intervals it is shown that the developed methods can be extended to compute the set of the Bernstein coefficients of all members of the polynomial family.
In tomato drying, degradation in final quality may occur based on the drying method used and predrying preparation. Hence, this research was conducted to evaluate the effect of different predrying treatments on physicochemical quality and drying kinetics of twin-layer-solar-tunnel-dried tomato slices. During the experimental work, tomato slices of var. Galilea were used. As predrying treatments, 0.5% calcium chloride (CaCl2), 0.5% ascorbic acid (C6H8O6), 0.5% citric acid (C6H8O7), and 0.5% sodium chloride (NaCl) were used. The tomato samples were sliced to 5 mm thickness, socked in the pretreatments for ten minutes, and dried in a twin layer solar tunnel dryer under the weather conditions of Jimma, Ethiopia. Untreated samples were used as control. The moisture losses from the samples were monitored by weighing samples at 2 h interval from each treatment. SAS statistical software version 9.2 was used for analyzing data on the physicochemical quality of tomato slices in CRD with three replications. From the experimental result, it was observed that dried tomato slices pretreated with 0.5% ascorbic acid gave the best retention of vitamin C and total phenolic content with a high sugar/acid ratio. Better retention of lycopene and fast drying were observed in dried tomato slices pretreated with 0.5% sodium chloride, and pretreating tomatoes with 0.5% citric acid resulted in better color values than the other treatments. Compared to the control, pretreating significantly preserved the overall quality of dried tomato slices and increased the moisture removal rate in the twin layer solar tunnel dryer.
Border issues continue to be of interest in tourism literature, most significantly that which focusses on cross-border shopping (e.g., currency values, taxation,
security). Borders as destinations are recognized in this area but the notion of shopping as a destination is perhaps less acknowledged. Following a review of the relevant literature, including the presentation of a table summarizing key areas of cross-border tourism research around the world, this paper presents a unique example of a border region with two-way traffic for cross-border shopping tourism: the border between Germany and Switzerland.
The particular case is where two cities meet at the border: Konstanz, Germany and Kreuzlingen, Switzerland. An intercept survey and key informant interviews were conducted in both communities in the spring of 2015. The results indicate high levels of traffic for various products and services. And while residents are generally satisfied with cross-border shopping in their communities, there are emerging issues related to volume and, in particular, too many in Konstanz and not enough in Kreuzlingen.
The paper concludes with a discussion that includes the development of a model cross-border shopping tourism that recognizes the multiple layers in space and destination.
The paper concludes with a proposal to further investigate the particular issues related to the volume on both sides of borders where cross-border shopping is the destination.
A conceptual framework for indigenous ecotourism projects – a case study in Wayanad, Kerala, India
(2020)
This paper analyses indigenous ecotourism in the Indian district of Wayanad, Kerala, using a conceptual framework based on a PATA 2015 study on indigenous tourism that includes the criteria: human rights, participation, business and ecology. Detailed indicator sets for each criterion are applied to a case study of the Priyadarshini Tea Environs with a qualitative research approach addressing stakeholders from the public sector, non-governmental organisations, academia, tour operators and communities including Adivasi and non-Adivasi. In-depth interviews were supported by participant and non-participant observations. The authors adapted this framework to the needs of the case study and consider that this modified version is a useful tool for academics and practitioners wishing to evaluate and develop indigenous ecotourism projects. The results show that the Adivasi involved in the Priyadarshini Tea Environs project benefit from indigenous ecotourism. But they could profit more if they had more involvement in and control of the whole tourism value chain.
Purpose – The purpose of this paper is to examine visitor management in the German-Swiss border area of the Lake Constance region. Taking a customer perspective, it determines the requirements for an application with the ability to optimize personal mobility.
Design/methodology/approach – A quantitative study and a survey of focus groups were conducted to identify movement patterns of different types of visitors and their requirements concerning the development of a visitor management application.
Findings – Visitors want an application that provides real-time forecasts of issues such as traffic, parking and queues and, at the same time, enables them to create a personal activity schedule based on this information.
Research limitations/implications – Not every subsample reached a sufficient number of cases to yield representative results.
Practical implications – The results may lead to an optimization and management separation of mobility flows in the research area and be helpful to municipal planners, destination marketing organizations and visitors.
Originality/value – The German border cities of Konstanz, Radolfzell and Singen in the Lake Constance region need improved visitor management, mainly because of a high level of shopping tourism by Swiss visitors to Germany. In the Summer months, Lake Constance is also a popular destination for leisure tourists, which causes overtourism. For the first time, the results of this research presented here offer possible solutions, in particular by showing how a mobile application for visitors could defuse the situation.
The aim of this paper is to portray the risks of climate change for low mountain range tourism and to develop sustainable business models as adaption strategy. A mixed-method-approach is applied combining secondary analysis, a quantitative survey, and qualitative in-depth-interviews in a transdisciplinary setting. Results show, that until now, climate change impacts on the snow situation in the Black Forest – at least above 1,000 m – have been mild and compensated by artificial snowmaking, and up to now have not had measurable effects on tourism demand. In general, the Black Forest appears to be an attractive destination for more reasons than just snow. The climate issue seems to be regarded as a rather incidental occurrence with little importance to current business decisions. However, the authors present adaption strategies as alternatives for snow tourism, e. g. the implementation of hiking hostels, since climate change will make winter tourism in the Black Forest impossible in the long run.
The Black Forest offers renewable energy as a specific tourist destination in the form of bioenergy villages (BEV). Particularly expert tourists tend to visit them. The results of two quantitative surveys on the supply and demand side show that there is, up to now, an untapped potential among experienceoriented
tourists for this type of niche tourism.
Für den deutschen bzw. europäischen Tourismus ist
Indien seit Jahrzehnten eine Destination, die kulturtouristisch,
aber auch zunehmend gesundheitstouristische
interessant ist. Sonderformen wie spiritueller
Tourismus, nachhaltiger Tourismus oder Tanztourismus
(Bollywood-Dance) haben sich in Nischen
etabliert oder beginnen diese zu verlassen. Indien
selbst unternahm mit seiner Kampagne „Incredible
India“ 2002 eine weltweit beachtete, selbstironische
Initiative, sich als „unglaubliche“ Destination in den
Auslandsmärkten zu positionieren. Demgegenüber
steht eine Realität in Indien, die einerseits Massenarmut,
Korruption, Sicherheitsprobleme, Bürokratie
und mangelnde Infrastruktur ebenso vorhält wie eine
beeindruckende Kultur- und Naturlandschaft, gut
ausgebildete englischsprachige Menschen, ethnische
Vielfalt sowie Mystik und Spiritualität. Indien definiert
sich – auch touristisch – durch Extreme (vgl. Freyer &
Thimm 2011: 261).
Während jeder Phase der touristischen Wertschöpfungskette spielen Wahrnehmungsprozesse eine relevante Rolle. Sofern es sich nicht um einen Wiederholungsbesucher handelt, kann der potenzielle Tourist zunächst nur auf das Image, das Fremdbild einer Destination, zurückgreifen, das nicht nur durch Tourismusmarketing, sondern auch durch andere Wahrnehmungsprozesse geformt wurde: immer wenn die Destination Gegenstand in einem Film, einer Nachrichtensendung oder einem Buch ist, trägt dies dazu bei, das Image zu formen. Somit ist nur ein Teil der touristischen Wahrnehmung vor der Reise eine durch Tourismusmarketing gesteuerte. Das Image oder Bild, das ein potenziell Reisender von einer Destination hat, kann somit über Jahre hinweg aufgebaut worden sein, durch Verbindung sämtlicher Eindrücke von ihr, die er im Laufe seines Lebens gesammelt hat. Diese inneren Bilder können individuell abweichen, weisen aber in vielen Fällen kollektive Gemeinsamkeiten auf (z. B. wird Paris mehrheitlich mit Romantik, mit der Südsee das Paradies und Berlin mit Party verbunden). Während und nach der Reise sucht der Tourist die Bestätigung dieser inneren Bilder – sie erweisen sich als persistent auch gegenüber der Realität. Diese Art der touristischen Wahrnehmung wird von Hennig (1997) treffend mit dem Begriff der „Imaginären Geographie“ beschrieben und soll daher zentraler Bezugspunkt dieses Beitrages sein. Angewendet wird dieses Konzept auf das Fallbeispiel Sevilla. Ziele des Beitrages sind daher:
- Aufzeigen des Erklärungspotenzialsdes Konzepts der „Imaginären Geographie“ von Christoph Hennig für touristische Wahrnehmungsprozesse
- Darstellung der Rolle der touristischen Intermediäre klassischer und neuer Reisemedienanhand des Fallbeispiels Sevilla
- Erläuterung des Bezugs der „Imaginäre Geographien“ (und verwandter Ansätze) zur Praxis (hier Fallbeispiel Sevilla)
The Kerala tourism model
(2017)
Sustainable tourism in Kerala is on the rise. Therefore, this South Indian state is assessed according to the sustainable tourism criteria of the Strasdas et al. (2007) framework. Kerala as a state does not qualify as a sustainable tourism destination, although individual success stories at the NGO and government level exist. This conceptual paper delivers a detailed analysis of the three dimensions of sustainability, i.e. ecology, economy and socio-cultural aspects, of the ‘Kerala tourism model’ and discusses the question of whether this model can be transferred to other developing countries. Copyright © 2016 John Wiley & Sons, Ltd and ERP Environment
Purpose The purpose of this paper is to find out tourism movement patterns via the tracking of tourists with the help of positioning systems like GPS in the rural area of the Lake Constance destination in Germany. In doing so past, present and future of tourist tracking is illustrated. Design/methodology/approach The tracking is realized via common smartphones extended by an app, with dedicated sensors like position loggers and a survey. The three different approaches are applied in order to compare and cross-check results (triangulation of data and methods). Findings Movement patterns turned out to be diverse and individualistic within the rural destination of Lake Constance and following an ants trail in sub-destinations like the city of Constance. Repeat visitors and first-time visitors alike always visit the bigger cities and main day-trip destinations of the Lake. A possible prediction tool enables new avenues of governing tourism movement patterns. Research limitations/implications The tracking techniques can be developed further into the direction of “quantified self” using gamification in order to make the tracking app even more attractive. Practical implications An algorithm-based prediction tool would offer new perspectives to the management of tourism movements. Social implications Further research is needed to overcome the feeling of invasiveness of the app to allow tracking with that approach. Originality/value This study is original and innovative because of the first-time use of a smartphone app in tourist tracking, the application on a rural destination and the conceptual description of a prediction tool.
Der Süden
(2018)
Dieser Beitrag untersucht, inwiefern die Sapir-Whorf-Hypothese, die die Abhängigkeit des Denkens von der Sprache postuliert, einen Erklärungsansatz zur raumsemantischen Konstruktion des touristischen Südens liefern kann. Sie dient als Analyseraster in Verbindung mit empirischen Befunden zu den touristischen Imageprofilen von Sevilla und Buenos Aires, die als Fallbeispiele touristischer Städte des Südens gewählt wurden.
This paper presents a framework to assess the cultural sustainability of Aboriginal tourism in British Columbia, which meets must take into account the protection of human rights, good self-governance, identity, control of land, the tourism product’s authenticity, and a market-ready tourism product. These criteria are specified by two indicators each. The cultural sustainability framework was generated by triangulating qualitative research methods like experts’ interviews, secondary research, and participant and non-participant observations. This paper is thus conceptual in nature and inductive in its approach. It partly leverages a collaborative approach, as it includes interviewees in an iterative research loop. Furthermore, the paper shows why cultural sustainability is a determinant of the success of Aboriginal tourism.
In diesem Beitrag wird der finnische Tangotanztourismus
unter Berücksichtigung des Konzeptes des verkörperten Raumes (Low 2003) und des Raumverständnisses von Lefebvre (1991) auf den vielschichtig miteinander verbundenen Ebenen von Körper, Kultur und Raum analysiert. Die finnische „Kultur der Schweigsamkeit“ wird in diesem Zusammenhang im Besonderen
betrachtet. Methodisch werden hierbei sowohl Interviews mit Expertinnen und Experten, teilnehmende Beobachtung als auch die Auswertung von Filmmaterial herangezogen. Im Ergebnis zeigen sich vielfältige Wechselwirkungen von Körper, Kultur und Raum, die zusätzlich Potenziale für den finnischen Tangotanztourismus
aufzeigen.
This paper applies the concept of Soja’s Thirdspace to the phenomenon of Lazgi dance and tourism in Uzbekistan. In doing so it analyses the different levels of perception (including Firstspace and Secondspace) of Lazgi and tourism via an autoethnographic lens. Complemented by expert interviews, the interaction of Lazgi and tourism is examined and characteristics of the Lazgisphere (world of Lazgi) in Uzbekistan are distilled. The results show that Lazgi is often directly or indirectly connected with tourism in Uzbekistan, but even more so serves to reaffirm national identity.
Flamenco und Tango gehören zu den ersten Assoziationen, mit denen Sevilla und Buenos Aires in Verbindung gebracht werden. Seit der Entstehung beider Kunstformen im 19. Jahrhundert entwickelte sich kontinuierlich ein Tanztourismus, der bis heute zu ausdifferenzierten Geschäftsmodellen führte. Flamenco und Tango erlangten als immaterielles Weltkulturerbe außerdem erhebliche Bedeutung für das Destinationsimage der beiden Städte. Das Modell von Gereffi et al. (2005) zu «Governance of Global Value Chains» wird in adaptierter Form auf Flamenco- und Tangotanztourismus angewendet, um Bedeutungsdimensionen im Destinationsmanagement herauszuarbeiten.
E-mobility in Tourism
(2018)
This article examines chances for and obstacles to e-mobility in tourism at the cross-border region of Lake Constance, Germany. Using secondary internet research, a database of key e-mobility supply factors was generated and visualized utilizing a geographical information system. The results show that fragmentation in infrastructure and information due to the cross-border situation of the four-country region is the main obstacle for e-mobility in tourism in the Lake Constance region. Cooperation and coordination of the supply side of e-mobility in the Lake Constance region turned out to be weak. To improve the chances of e-mobility in cross-border tourism a more client-oriented approach regarding information, accessibility, and conditions of use is necessary.
A post-growth economy is a comparatively new paradigm in the tourism discourse. The aim of this article is to find out the commonalities between this concept and Māori tourism and in which way the latter can contribute to a post-growth economy. A qualitative mixed method approach, including in-depth-interviews, participant observation, and secondary analysis is applied. The results show that there is a lot of overlap between Māori tourism and a post-growth economy. Differences are visible, as well, regarding the value approach of Māori tourism and the indicator approach of a post-growth economy. Especially the social innovation created in Aotearoa New Zealand at the instigation of Māori groups of granting legal personhood to parts of nature may serve as a driver for a form of tourism that is in line with the idea of a post-growth economy.
The aim of this paper is to find out in how accommodation providers in the Seychelles perceive climate change and what mitigation and adaptation measures they can provide. In order to answer these questions, a qualitative mixed-method-approach, comprised of twenty semi-structured interviews, an online-survey and participant observation was used. Results show that accommodation providers especially perceive the effects of climate change that directly affect their business and that they have already partly implemented some mitigation and adaptation measures. However, strategies and regulations are needed at the Seychelles’ government level and on a global level to actually achieve CO2 neutral travel.
This paper examines the interdependencies of tourism, Buddhism and sustainability combining in-depth-interviews with Buddhism experts and non-participant observation in a mixed-method approach. The area under investigation is the Alpine region of Austria, Germany and Switzerland, since it is home to Asian and Western forms of Buddhism tourism alike. Results show that Buddhism tourism as a value-based activity on the one hand is not commercial, but since demand is rising, on the other hand tendencies towards more commercial forms can be observed. As a modest form of activity Buddhism tourism does not shape the landscape of the Alpine area and by its nature it incorporates sustainability.
Code-based cryptosystems are promising candidates for post-quantum cryptography. Recently, generalized concatenated codes over Gaussian and Eisenstein integers were proposed for those systems. For a channel model with errors of restricted weight, those q-ary codes lead to high error correction capabilities. Hence, these codes achieve high work factors for information set decoding attacks. In this work, we adapt this concept to codes for the weight-one error channel, i.e., a binary channel model where at most one bit-error occurs in each block of m bits. We also propose a low complexity decoding algorithm for the proposed codes. Compared to codes over Gaussian and Eisenstein integers, these codes achieve higher minimum Hamming distances for the dual codes of the inner component codes. This property increases the work factor for a structural attack on concatenated codes leading to higher overall security. For comparable security, the key size for the proposed code construction is significantly smaller than for the classic McEliece scheme based on Goppa codes.
Generalized Concatenated Codes over Gaussian and Eisenstein Integers for Code-Based Cryptography
(2021)
The code-based McEliece and Niederreiter cryptosystems are promising candidates for post-quantum public-key encryption. Recently, q-ary concatenated codes over Gaussian integers were proposed for the McEliece cryptosystem together with the one-Mannheim error channel, where the error values are limited to Mannheim weight one. Due to the limited error values, the codes over Gaussian integers achieve a higher error correction capability than maximum distance separable (MDS) codes with bounded minimum distance decoding. This higher error correction capability improves the work factor regarding decoding attacks based on information-set decoding. The codes also enable a low complexity decoding algorithm for decoding beyond the guaranteed error correction capability. In this work, we extend this coding scheme to codes over Eisenstein integers. These codes have advantages for the Niederreiter system. Additionally, we propose an improved code construction based on generalized concatenated codes. These codes extent the rate region where the work factor is beneficial compared to MDS codes. Moreover, generalized concatenated codes are more robust against structural attacks than ordinary concatenated codes.
Large-scale quantum computers threaten the security of today's public-key cryptography. The McEliece cryptosystem is one of the most promising candidates for post-quantum cryptography. However, the McEliece system has the drawback of large key sizes for the public key. Similar to other public-key cryptosystems, the McEliece system has a comparably high computational complexity. Embedded devices often lack the required computational resources to compute those systems with sufficiently low latency. Hence, those systems require hardware acceleration. Lately, a generalized concatenated code construction was proposed together with a restrictive channel model, which allows for much smaller public keys for comparable security levels. In this work, we propose a hardware decoder suitable for a McEliece system based on these generalized concatenated codes. The results show that those systems are suitable for resource-constrained embedded devices.
The performance and reliability of non-volatile NAND flash memories deteriorate as the number of program/erase cycles grows. The reliability also suffers from cell to cell interference, long data retention time, and read disturb. These processes effect the read threshold voltages. The aging of the cells causes voltage shifts which lead to high bit error rates (BER) with fixed pre-defined read thresholds. This work proposes two methods that aim on minimizing the BER by adjusting the read thresholds. Both methods utilize the number of errors detected in the codeword of an error correction code. It is demonstrated that the observed number of errors is a good measure for the voltage shifts and is utilized for the initial calibration of the read thresholds. The second approach is a gradual channel estimation method that utilizes the asymmetrical error probabilities for the one-to-zero and zero-to-one errors that are caused by threshold calibration errors. Both methods are investigated utilizing the mutual information between the optimal read voltage and the measured error values.
Numerical results obtained from flash measurements show that these methods reduce the BER of NAND flash memories significantly.
Infrastructure-making in interwar India was a dynamic, multilayered process involving roads and vehicles in urban and rural sites. One of their strongest playgrounds was Bombay Presidency and the Central Provinces in central and western India. Focusing on this region in the interwar period, this paper analyzes the varied relationship between peasant households and town-centred modernizing agents in the making of road transport infrastructures. The central argument of this paper is about the persistence of bullock carts over motor cars in the region. This persistence was grounded in the specific regional environment, the effects of the 1930s economic depression, and the priorities of social classes. Pinpointing these connections, the paper highlights that “modernization” of infrastructure was not a simple, linear process of progressivist change, nor did it mean the survival of apparently “old” technologies in the modern era. Instead, the paper pays attention to conflicting social complexities, implications, and meanings of the connection between infrastructure and modernity that modernization assumptions often overlook. Here, the paper shows how technological change occurred as a result of real, material class interests pulling infrastructural technology in different directions. This was where and why arguments of road-motor lobbyists and cart advocates eventually clashed, and Gandhian social workers resisted motor transport in defense of peasant interests.
This paper introduces the third update/release of the Global Sanctions Data Base (GSDB-R3). The GSDB-R3 extends the period of coverage from 1950–2019 to 1950–2022, which includes two special periods—COVID-19 and the new sanctions against Russia. This update of the GSDB contains a total of 1325 cases. In response to multiple inquiries and requests, the GSDB-R3 has been amended with a new variable that distinguishes between unilateral and multilateral sanctions. As before, the GSDB comes in two versions, case-specific and dyadic, which are freely available upon request at GSDB@drexel.edu. To highlight one of the new features of the GSDB, we estimate the heterogeneous effects of unilateral and multilateral sanctions on trade. We also obtain estimates of the effects on trade of the 2014 sanctions on Russia.
Although the Hospice Foundation in Constance knew they had a personnel
problem, they were unsure how to begin to fix it. In addition to difficulties in
finding and keeping employees, the Hospice Foundation’s employees were
often on sick leave, adding pressure on remaining staff. Twelve communication
design students in the masters program at the University of Applied
Sciences in Constance (HTWG Konstanz) conducted a study aimed at
identifying the causes for these problems and, more generally, understanding
how the employees work and feel. Even though the methods in this
study are well known, it presents an important prototype for designers and
design researchers because of its success in finding useful insights. It also
serves as a pre-design project briefing for both management and designers.
It demonstrates the usefulness of qualitative methods in providing a deeper
understanding of a complex situation and its usefulness as a strategic tool
and for defining a project’s focus and scope. Ideally, it also provides insights
into health care for the elderly.
R concretes with a proportion of recycled aggregates are standardized normal concretes which are allowed for use in Germany up to strength class C30/37. Because of the good technical properties and the ecological advantages, the article presents possible applications in the field of concrete products and precast concrete elements. Read part 2 of the paper.
R concretes with a proportion of recycled aggregates are standardized normal concretes which are allowed for use in Germany up to strength class C30/37. Because of the good technical properties and the ecological advantages, the article presents possible applications in the field of concrete products and precast concrete elements. Read part 1 of the paper.
Weder für moderne Recycling-Betone gemäß Regelwerk noch für Ziegelsplittbetone der Nachkriegsjahre bestehen prinzipielle Bedenken gegen deren Einsatz oder die Weiternutzung im Hochbau. Die Autoren wünschen sich mehr Akzeptanz und Vertrauen in Recyclingbaustoffe und dass sich für "Vintage" im Baubereich irgendwann ein ähnliches Interesse herausbildet wie für Vintage-Möbel oder Used-Look-Kleidung - und dies nicht nur hinsichtlich der Wiederverwendung gebrauchter Türen und Treppen, sondern auch für mineralische Massenbaustoffe wie Beton. Der Beitrag veranschaulicht anhand erfolgreich realisierter Objektbeispiele, wie Hochhäuser (z.B. das Studentenwohnheim Max-Kade-Haus in Stuttgart, 1953, aus Bauschuttbeton) oder Sakralgebäude (Fatima-Kirche in Kassel aus Sichtbeton mit Ziegelbruch, 60 Jahre alt) sowie auch Verwaltungsbauten (Technisches Rathaus in Tübingen aus den 1950er Jahren) erfolgreich und nachhaltig mit Recyclingmaterialien errichtet wurden.
Von wegen Bauschutt
(2020)
RC-Betone sind keine Neu-Entwicklungen, aber sie erleben seit circa 15 Jahren in Deutschland eine Renaissance mit Materialzusammensetzungen, die den heutigen Anforderungen an Normalbetone gerecht werden. Es gab immer wieder Abschnitte in der (Bau-)Geschichte, in denen Gebäude aus Ziegelsplitt-Betonen errichtet wurden, wie das Max-Kade-Studentenwohnheim in Stuttgart und das Technische Rathaus in Tübingen. Beide stammen aus der Nachkriegszeit und weisen einen guten Erhaltungszustand auf. Sie sind Beispiele für die Bewährung "historischer" Ziegelsplitt-Betone in der Baupraxis und ihre lange technische Lebensdauer.
Die Quadratur der Risse
(2015)
Lokale Ausbesserungen stellen bei Schadstellen an verputzten Fassaden in vielen Fällen eine technisch sichere und weniger zeit- und kostenaufwendige Alternative zum Putzabschlagen und Neuverputz oder zum vollflächigen Überputzen dar.
Die zum Teil damit verbundenen leichten Einschränkungen beim ästhetischen Gesamteindruck sind in den meisten Fällen tolerierbar. An die Auswahl eines geeigneten Putzes und die handwerkliche Ausführung der Ausbesserung werden hohe Anforderungen gestellt, um ein technisch und ästhetisch zufriedenstellendes Ergebnis zu erzielen.
Mit Injektionen Risse heilen
(2015)
Um Mauerwerksrisse mit einer Injektion erfolgreich zu schließen, sind bei der praktischen Durchführung des Injektionsverfahrens eine Reihe von Details zu beachten: Sie betreffen das Bohren und Setzen der Packer, das Mischen und Einbringen des Füllstoffs, das Schließen der Öffnungen und Fertigstellen der Sichtmauerwerksoberflächen sowie die Dokumentation und Kontrolle des Injektionserfolgs.
Die Putzstrukturen an Fassaden werden maßgeblich durch die Fachhandwerker geprägt. Deshalb wird ihre Ebenmäßigkeit auch nie mit der von industriell gefertigten Fassadenplatten und Ähnlichem vergleichbar sein – aber genau das macht einen Teil des Charmes von Putzfassaden aus. Dies ist auch bei der Bearbeitung von Schadstellen zu berücksichtigen.
Für mehr Qualität am Bau
(2018)
Die Datenschutz-Grundverordnung (DSGVO) sieht in Art. 82 DSGVO einen Anspruch auf Ersatz materieller und immaterieller Schäden vor, allerdings ohne Aussagen darüber, wie die Schadenshöhe zu bestimmen ist. Der Beitrag beleuchtet die bisherige Gerichtspraxis kritisch und zeigt auf, welche Kriterien speziell in data leakage-Fällen herangezogen werden können, um die Schadenshöhe zu bestimmen. Aus der Sicht von Betroffenen stellt sich die Frage nach effektiver Rechtsdurchsetzung, aus der Sicht von Unternehmen stellt sich die Frage nach Prävention und Abwehr von Ansprüchen.
Die Bedeutung immaterieller Rechtsgüter nimmt in der Unternehmensrealität ständig zu. Dieser Bedeutungszuwachs hat einen festen betriebswirtschaftlichen Hintergrund: Zunehmend bestimmen nicht mehr Sachanlagevermögen, Geschäftsbeziehungen oder die Mitarbeiter den Unternehmenswert, sondern überwiegend das Intellectual Property (kurz auch: IP).1 Der Begriff Intellectual Property meint im Folgenden das durch Schutzrechte kodifizierte Wissen, also Patente, Gebrauchsmuster, Marken, Geschmacksmuster und sonstige Schutzrechte (gewerbliche Schutzrechte) sowie Urheberrechte. Diese Schutzrechte vermitteln absolute Verwertungsrechte und damit Monopolrechte, die es den Inhabern ermöglicht, das geschützte IP für eine bestimmte Schutzdauer allein und unter Ausschluss unbefugter Dritter zu verwerten.
Auch die Bedeutung von IT nimmt in der Unternehmenspraxis ständig zu.
Thermal shape memory alloys show extraordinary material properties and can be used as actuators, dampers and sensors. Since their discovery in the middle of the last century they have been investigated and further developed. The majority of the industrial applications with the highest material sales can still be found in the medical industry, where they are used due to their superelastic and thermal shape memory effect, e.g. as stents or as guidewires and tools in the minimal invasive surgery. Particularly in recent years, more and more applications have been developed for other industrial fields, e.g. for the household goods, civil engineering and automotive sector. In this context it is worth mentioning that for the latter sector, million seller series applications have found their way into some European automobile manufacturers. The German VDI guideline for shape memory alloys introduced in 2017 will give the material a further boost in application. Last but not least the new production technologies of additive manufacturing with metal laser sintering plants open up additional applications for these multifunctional materials. This paper gives an overview of the extraordinary material properties of shape memory components, shows examples of different applications and discusses European trends against the background of the most recent standard and new production technologies.
In automotive a lot of electromagnetically, pyrotechnically or mechanically driven actuators are integrated to run comfort systems and to control safety systems in modern passenger cars. Using shape memory alloys (SMA) the existing systems could be simplified, performing the same function through new mechanisms with reduced size, weight, and costs. A drawback for the use of SMA in safety systems is the lack of materials knowledge concerning the durability of the switching function (long-time stability of the shape memory effect). Pedestrian safety systems play a significant role to reduce injuries and fatal casualties caused by accidents. One automotive safety system for pedestrian protection is the bonnet lifting system. Based on such an application, this article gives an introduction to existing bonnet lifting systems for pedestrian protection, describes the use of quick changing shape memory actuators and the results of the study concerning the long-time stability of the tested NiTi-wires. These wires were trained, exposed up to 4years at elevated temperatures (up to 140°C) and tested regarding their phase change temperatures, times, and strokes. For example, it was found that A P-temperature is shifted toward higher temperatures with longer exposing periods and higher temperatures. However, in the functional testing plant a delay in the switching time could not be detected. This article gives some answers concerning the long-time stability of NiTi-wires that were missing till now. With this knowledge, the number of future automotive applications using SMA can be increased. It can be concluded, that the use of quick changing shape memory actuators in safety systems could simplify the mechanism, reduce maintenance and manufacturing costs and should be insertable also for other automotive applications.
Characterization of NiTi Shape Memory Damping Elements designed for Automotive Safety Systems
(2014)
Actuator elements made of NiTi shape memory material are more and more known in industry because of their unique properties. Due to the martensitic phase change, they can revert to their original shape by heating when subjected to an appropriate treatment. This thermal shape memory effect (SME) can show a significant shape change combined with a considerable force. Therefore such elements can be used to solve many technical tasks in the field of actuating elements and mechatronics and will play an increasing role in the next years, especially within the automotive technology, energy management, power, and mechanical engineering as well as medical technology. Beside this thermal SME, these materials also show a mechanical SME, characterized by a superelastic plateau with reversible elongations in the range of 8%. This behavior is based on the building of stress-induced martensite of loaded austenite material at constant temperature and facilitates a lot of applications especially in the medical field. Both SMEs are attended by energy dissipation during the martensitic phase change. This paper describes the first results obtained on different actuator and superelastic NiTi wires concerning their use as damping elements in automotive safety systems. In a first step, the damping behavior of small NiTi wires up to 0.5 mm diameter was examined at testing speeds varying between 0.1 and 50 mm/s upon an adapted tensile testing machine. In order to realize higher testing speeds, a drop impact testing machine was designed, which allows testing speeds up to 4000 mm/s. After introducing this new type of testing machine, the first results of vertical-shock tests of superelastic and electrically activated actuator wires are presented. The characterization of these high dynamic phase change parameters represents the basis for new applications for shape memory damping elements, especially in automotive safety systems.
Dass sich Stoffe bei Temperaturänderungen zusammenziehen beziehungsweise ausdehnen, ist eine uralte Erkenntnis. Diesbezüglich stechen Formgedächtnislegierungen heraus, da diese die verblüffende Eigenschaft besitzen, sich bei Temperaturänderung ungewöhnlich rasch zusamenzuziehen beziehungsweise auszudehnen. Eine physikalische Besonderheit, die sich auf vielfältige Weise nutzen lässt.
Im modernen Automobilbau spielen Fussgängerschutzsysteme eine immer stärker werdende Rolle, um Verletzungen und Todesfälle bei Verkehrsunfällen mit Fussgängerbeteiligung zu reduzieren. Eines dieser Sicherheitssysteme ist die aktive Motorhaube. Durch die Verwendung von Formgedächtnislegierungen (FGL) als Aktoren können die bestehenden Systeme vereinfacht werden, wobei die gleiche Funktion durch neue Mechanismen bei reduzierter Grösse und Gewicht sowie verringerten Kosten ausgeführt werden kann. In diesem Beitrag werden nach einer Einleitung zu existierenden Systemen zur Motorhauben-Anhebung FG-Aktoren und deren potenzielle Einsatzmöglichkeiten in Automobilbau kurz vorgestellt.
This paper describes the rationale and the development of a structured digital approach for measuring corporate environmental sustainability using performance metrics.
It is impossible to imagine today's age without the preservation of our environment, not even in the corporate environment. Currently, sustainability is mostly only rudimentarily considered in companies, mostly only with written down phrases on the website. This will no longer be sufficient in the future, which is why companies should record sustainability on a numerical basis. Based on the development of a workable concept for companies, a small empirical study was carried out, which can be used to numerically measure the sustainability performance of companies. Two utility analyses were completed.
One of them was supplemented by expert interviews. Well-known practitioners from the business world were interviewed and asked for their assessment of ecological performance indicators. The result of the research is an indicator-based concept that can be applied in corporate practice to determine ecological sustainability performance.
Generalised concatenated (GC) codes are well suited for error correction in flash memories for high-reliability data storage. The GC codes are constructed from inner extended binary Bose–Chaudhuri–Hocquenghem (BCH) codes and outer Reed–Solomon codes. The extended BCH codes enable high-rate GC codes and low-complexity soft input decoding. This work proposes a decoder architecture for high-rate GC codes. For such codes, outer error and erasure decoding are mandatory. A pipelined decoder architecture is proposed that achieves a high data throughput with hard input decoding. In addition, a low-complexity soft input decoder is proposed. This soft decoding approach combines a bit-flipping strategy with algebraic decoding. The decoder components for the hard input decoding can be utilised which reduces the overhead for the soft input decoding. Nevertheless, the soft input decoding achieves a significant coding gain compared with hard input decoding.
This paper proposes a soft input decoding algorithm and a decoder architecture for generalized concatenated (GC) codes. The GC codes are constructed from inner nested binary Bose-Chaudhuri-Hocquenghem (BCH) codes and outer Reed-Solomon codes. In order to enable soft input decoding for the inner BCH block codes, a sequential stack decoding algorithm is used. Ordinary stack decoding of binary block codes requires the complete trellis of the code. In this paper, a representation of the block codes based on the trellises of supercodes is proposed in order to reduce the memory requirements for the representation of the BCH codes. This enables an efficient hardware implementation. The results for the decoding performance of the overall GC code are presented. Furthermore, a hardware architecture of the GC decoder is proposed. The proposed decoder is well suited for applications that require very low residual error rates.
Flash-Speicher wurden ursprünglich als Speichermedium für Digitalkameras entwickelt, finden inzwischen aber in vielen Bereichen Anwendung.
Die in Konstanz ansässige Firma Hyperstone GmbH ist ein führender Anbieter von Flashcontrollern für Anwendungen mit erhöhten Anforderungen an Zuverlässigkeit und Datenintegrität. Bereits seit April 2011 kooperiert die Firma Hyperstone mit der HTWG Konstanz bei der Entwicklung von Fehlerkorrekturverfahren für einen zuverlässigen Einsatz von Flash-Speichern. Aufgrund der rasanten Entwicklung bei Flashspeicherbausteinen ist auch eine stetige Weiterentwicklung der Korrekturverfahren notwendig. Im Rahmen dieser Kooperation wurde inzwischen zwei Flashcontroller mit sehr leistungsfähiger Fehlerkorrektur entwickelt. Der folgende Artikel gibt Einblick in den Einsatz von Flash-Speichern und erläutert die Notwendigkeit für eine leistungsfähige Fehlerkorrektur.
This paper proposes a pipelined decoder architecture for generalised concatenated (GC) codes. These codes are constructed from inner binary Bose-Chaudhuri-Hocquenghem (BCH) and outer Reed-Solomon codes. The decoding of the component codes is based on hard decision syndrome decoding algorithms. The concatenated code consists of several small BCH codes. This enables a hardware architecture where the decoding of the component codes is pipelined. A hardware implementation of a GC decoder is presented and the cell area, cycle counts as well as the timing constraints are investigated. The results are compared to a decoder for long BCH codes with similar error correction performance. In comparison, the pipelined GC decoder achieves a higher throughput and has lower area consumption.
In beispielhafter Zusammenarbeit zwischen Industrie (Geobrugg AG, Romanshorn/Schweiz) und Wissenschaft (WITg Institut für Werkstoffsystemtechnik Thurgau an der Hochschule Konstanz, Tägerwilen/Schweiz) wurde mit Unterstützung der Schweizer staatlichen Innovationsförderung (KTI, hee Innosuisse) ein neues Werkstoff- und Fertigungskonzept für den Bau von Fischzuchtnetzen aus hochfesten nichtrostenden Stahldrähten entwickelt.
Diese Entwicklung wurde 2019 von Swiss Inox, der Schweizer Innovationspreis Prix Inox ausgezeichnet.
Purpose
In order to combat climate change and safeguard a liveable future we need fundamental and rapid social change. Climate communication can play an important role to nurture the public engagement needed for this change, and higher education for sustainability can learn from climate communication.
Approach
The scientific evidence base on climate communication for effective public engagement is summarised into ten key principles, including ‘basing communication on people’s values’, ‘conscious use of framing’, and ‘turning concern into action’. Based on the author’s perspective and experience in the university context, implications are explored for sustainability in higher education.
Findings
The article provides suggestions for teaching (e.g. complement information with consistent behaviour by the lecturer, integrate local stories, and provide students with basic skills to communicate climate effectively), for research (e.g. make teaching for effective engagement the subject of applied research), for universities’ third mission to contribute to sustainable development
in the society (e.g. provide climate communication trainings to empower local stakeholders), andgreening the campus (develop a proper engagement infrastructure, e.g. by a university storytelling exchange on climate action).
Originality
The article provides an up-to-date overview of climate communication research, which is in itself original. This evidence base holds interesting learnings for institutions of higher education, and the link between climate communication and universities has so far not been explored comprehensively.