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Sharing marketplaces emerged as the new Holy Grail of value creation by enabling exchanges between strangers. Identity reveal, encouraged by platforms, cuts both ways: While inducing pre-transaction confidence, it is suspected of backfiring on the information senders with its discriminative potential. This study employs a discrete choice experiment to explore the role of names as signifiers of discriminative peculiarities and the importance of accompanying cues in peer choices of a ridesharing offer. We quantify users' preferences for quality signals in monetary terms and evidence comparative disadvantage of Middle Eastern descent male names for drivers and co-travelers. It translates into a lower willingness to accept and pay for an offer. Market simulations confirm the robustness of the findings. Further, we discover that females are choosier and include more signifiers of involuntary personal attributes in their decision-making. Price discounts and positive information only partly compensate for the initial disadvantage, and identity concealment is perceived negatively.
In nowadays production, fluctuations in demand, shortening product life-cycles, and highly configurable products require an adaptive and robust control approach to maintain competitiveness. This approach must not only optimise desired production objectives but also cope with unforeseen machine failures, rush orders, and changes in short-term demand. Previous control approaches were often implemented using a single operations layer and a standalone deep learning approach, which may not adequately address the complex organisational demands of modern manufacturing systems. To address this challenge, we propose a hyper-heuristics control model within a semi-heterarchical production system, in which multiple manufacturing and distribution agents are spread across pre-defined modules. The agents employ a deep reinforcement learning algorithm to learn a policy for selecting low-level heuristics in a situation-specific manner, thereby leveraging system performance and adaptability. We tested our approach in simulation and transferred it to a hybrid production environment. By that, we were able to demonstrate its multi-objective optimisation capabilities compared to conventional approaches in terms of mean throughput time, tardiness, and processing of prioritised orders in a multi-layered production system. The modular design is promising in reducing the overall system complexity and facilitates a quick and seamless integration into other scenarios.
Algorithmic management
(2022)
Clubs of autocrats
(2021)
While scholars have argued that membership in Regional Organizations (ROs) can increase the likelihood of democratization, we see many autocratic regimes surviving in power albeit being members of several ROs. This article argues that this is the case because these regimes are often members in "Clubs of Autocrats" that supply material and ideational resources to strengthen domestic survival politics and shield members from external interference during moments of political turmoil. The argument is supported by survival analysis testing the effect of membership in autocratic ROs on regime survival between 1946 to 2010. It finds that membership in ROs composed of more autocratic member states does in fact raise the likelihood of regime survival by protecting incumbents against democratic challenges such as civil unrest or political dissent. However, autocratic RO membership does not help to prevent regime breakdown due to autocratic challenges like military coups, potentially because these types of threats are less likely to diffuse to other member states. The article thereby adds to our understanding of the limits of democratization and potential reverse effects of international cooperation, and contributes to the literature addressing interdependences of international and domestic politics in autocratic regimes.
Die Herstellung von Produkten bindet Energie sowie auch materielle Ressourcen. Viel zu langsam entwickeln sich sowohl das Bewusstsein der Konsumenten sowie der Produzenten als auch gesetzgebende Aktivitäten, um zu einem nachhaltigen Umgang mit den zur Verfügung stehenden Ressourcen zu gelangen. In diesem Beitrag wird ein lokaler Remanufacturing-Ansatz vorgestellt, der es ermöglicht, den Ressourcenverbrauch zu reduzieren, lokale Unternehmen zu fördern und effiziente Lösungen für die regionale Wieder- und Weiterverwendung von Gütern anzubieten.
Strategic social media use positively influences organizational goals such as the long-term accrual of social capital, and thus social media information governance has become an increasingly important organizational objective. It is particularly important for humanitarian nongovernmental organizations (HNGOs), whose work relies on accurate and timely information regarding socially altruistic behavior (donations, volunteerism, etc.). Despite the potential of social media for increasing social capital, tensions in governing social media information across an organization's different operational levels (regional, intermediate, and national) pose a difficult challenge. Prominent governance frameworks offer little guidance, as their focus on control and incremental policymaking is largely incompatible with the processes, roles, standards, and metrics needed for managing self-governing social media. This study offers a notion of dynamic and co-evolutionary process management of multi-level organizations as a means of conceptualizing social media information governance for the accrual of organizational social capital. Based on interviews with members of HNGOs, this study reveals tensions that emerge within eight focus areas of accruing social capital in multi-level organizations, explains how dynamic process management can ease those tensions, and proposes corresponding strategy recommendations.
Many international organisations (IOs) are currently challenged, yet are they also in decline? Despite much debate on the crisis of liberal international order, con-testation, loss of legitimacy, gridlock, pathologies and exiting member states, there is little research on IO decline. This article seeks to clarify this concept and argues that decline can be considered in absolute and relative terms. Absolute decline involves a decrease in the number of IOs and their authority, member-ship and output, whereas relative decline concerns a decrease in the centrality of IOs in international relations. Reviewing a wide range of indicators, this article argues that, whereas there is limited decline in absolute terms since 1945, there may well be important decline in relative terms. Relative decline is more difficult to measure, but to probe its significance this article presents data from speeches during the United Nations General Assembly General Debate. It shows that IOs were most often mentioned in 1996 and that there has been a decline since. These findings indicate that, whereas IOs might survive as institutions, they are decreasingly central to international relations.
Governance abhors a vacuum
(2023)
International organisations have become increasingly contested resulting in worries about their decline and termination. While international organisation termination is indeed a regular event in international relations, this article shows that other institutions carry the legacy of terminated international organisations. We develop the novel concept of international organisation afterlife and suggest indicators to systematically assess it. Our analysis of 26 major terminated international organisations reveals legal-institutional and asset continuity in 21 cases. To further illustrate this point, the article zooms in on the afterlife of the International Institute of Agriculture in the Food and Agriculture Organization, the International Refugee Organization in the United Nations High Commissioner for Refugees, and the Western European Union in the European Union. In these three cases, international organisation afterlife inspired and structured the design of their successor institutions. While specific international organisations might be terminated, international cooperation therefore often lives on in other institutions.
The control of residual stress (RS) remains a challenge in the manufacturing of metallic parts using the laser powder bed fusion process (LPBF). This layer-by-layer manufacturing approach gives rise to complex triaxial RS distributions, which require extensive characterization effort for a broader acceptance of LPBF in industry. This study focuses on the distribution of bulk triaxial RS and surface RS in LPBF austenitic steel 316L. The RS are determined by X-ray and neutron diffraction to characterize the RS distribution. Variations in the LPBF parameters interlayer time (ILT) and scanning velocity and their influence on the temperature distribution and resulting RS is investigated using thermographic data from in situ process monitoring. The RS in the LPBF 316L is tensile at the surface and compressive in the bulk. The RS is directly related to the thermal history of the part as shown by the in situ thermography data. Shorter ILT leads to higher temperatures of the part during the manufacturing, which decrease the RS and RS formation mechanisms. Interestingly, the surface RS does not agree with this observation. This study highlights the benefit of using multiple RS determination methods and in situ thermography monitoring to characterize the RS in LPBF processed parts.
Visible light is shown to create a transient metallic S-Mo-S surface layer on bulk semiconducting p-doped indirect-bandgap 2H-MoS2. Optically created electron-hole pairs separate in the surface band bending region of the p-doped semiconducting crystal causing a transient accumulation of electrons in the surface region. This triggers a reversible 2H-semiconductor to 1T-metal phase-transition of the surface layer. Electron-phonon coupling of the indirect-bandgap p-doped 2H-MoS2 enables this efficient pathway even at a low density of excited electrons with a distinct optical excitation threshold and saturation behavior. This mechanism needs to be taken into consideration when describing the surface properties of illuminated p-doped 2H-MoS2. In particular, light-induced increased charge mobility and surface activation can cause and enhance the photocatalytic and photoassisted electrochemical hydrogen evolution reaction of water on 2H-MoS2. Generally, it opens up for a way to control not only the surface of p-doped 2H-MoS2 but also related dichalcogenides and layered systems. The findings are based on the sensitivity of time-resolved electron spectroscopy for chemical analysis with photon-energy-tuneable synchrotron radiation.