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International audience; The Electron Beam Melting (EBM) process has emerged as either an alternative or a complement to vacuum arc remelting of titanium alloys, since it is capable of enhancing the removal of exogenous inclusions by dissolution or sedimentation. The melting of the primary material is a first step of this continuous process, which has not been studied so far and is investigated experimentally and numerically in the present study. Experiments have been set up in a 100 kW laboratory furnace with the aim of analyzing the effect of melting rate on surface temperature of Ti-64 bars. It was found that melting rate is nearly proportional to the EB power while the overheating temperature remains roughly independent of the melting rate and equal to about 100 °C. The emissivity of molten Ti-64 was found to be 0.22 at an average temperature of about 1760 °C at the tip of the bar. In parallel, a mathematical model of the thermal behavior of the material during melting has been developed. The simulations revealed valuable results about the melting rate, global heat balance and thermal gradient throughout the bar, which agreed with the experimental values to a good extent. The modeling confirms that the overheating temperature of the tip of the material is nearly independent of the melting rate.

Firms increasingly face fragmented institutional environments where stakeholders endorse different institutional logics. Although the effects of market specialization have been extensively studied, we do not know much about the firm-level implications of institutional specialization, i.e., when firms demonstrate consistent conformity to an institutional logic. In this study, I explore whether and to what extent institutional specialization affects firm survival. In contrast with arguments and evidence highlighting the potential negative survival effect of market specialization, I posit that institutional specialization is positively associated with survival. Because they may be more skilled at interacting with stakeholders, which perceive them as more appealing and understandable, institutional specialists, I argue, are more likely than other firms to form and maintain the reciprocal stakeholder relationships needed to operate and survive. I expect the survival benefit of institutional specialization to be accentuated when the contrast between logics decreases. I test and find support for these ideas using unique population data on French film producers (1994–2008).

International audience; Recent works have documented the dark side of scandals, revealing how they spread, contaminate associated organizations, and taint the perception of entire fields. We complement this line of work by exploring how scandals durably affect competition within a field, translating into relative advantages for certain organizations over others. First, scandals may benefit organizations that provide a close substitute to the offerings of the implicated organization. Second, scandals pave the way for moralizing discourses and practices, shake taken-for-granted assumptions about the conduct of organizations, and result in a shift in the criteria used to evaluate organizations within the field. Our arguments suggest that organizations whose offerings are most similar to those of the implicated organization, yet perceived as enforcing stricter standards of conduct, are likely to benefit the most from a scandal. We find support for these arguments in a county-level study of membership in the Catholic Church and sixteen other Christian denominations in the United States in the wake of a series of sex abuse cases perpetrated by Catholic clergy between 1971 and 2000. This study contributes to our understanding of the competitive effects of scandals on organizations, and carries important implications for the management of organizations in scandal-stricken fields.

Vacuum processing techniques are a valuable industrial tool for the processing of reactive metals and alloys. However, drawbacks caused by the selective volatilization of alloying elements lead to an hard prediction of final alloy composition. By understanding the behaviour of the alloying elements and the interactions between them, improved compositional accuracy can be achieved. The evaluation of the activity coefficients is a key property that relates partial vapor pressure with the Langmuir law to accurately predict the mass flux of the individual elements in an alloy. This study takes a look at the grade Ti-17 which exhibits a relative large number of alloying elements. By using an electron beam furnace and a vapor deposition apparatus the necessary measurements were made to evaluate activity coefficients for each of the volatizing elements in the alloys including Aluminum, Chromium, Tin. Comparisons were made between experiments and the findings suggest that the primary interactions between the alloying elements with titanium result in small deviations between alloys. The results for the experiments provided reliable and repeatable results.

Understanding the arc dynamics during VAR is important for controlling the final quality of the ingot, as the spatial and temporal distribution of the arc dictates the electric current and energy inputs at the ingot top, which in turn affect the hydrodynamics of the metal in the molten pool and the solidification conditions of the ingot. The arc dynamics during vacuum arc remelting was quantitatively investigated based on the analysis of the light emitted by the arc and reflected by the molten pool using photodiodes placed inside a full-scale furnace. The measurements allowed us to determine the location of the arc luminosity centroid and to follow its displacement as a function of time. They were made during the melt of a Ti64 alloy with an imposed alternated electromagnetic stirring of high intensity. The arc dynamics was found to be most of the time periodic, asymmetrical, and strongly correlated to the evolution of the stirring magnetic field. The arc centroid exhibited three regular displacement patterns throughout the melt. A common characteristic to all three patterns was the relative stability of the centroid during stirring plateaus and its rapid motion during stirring ramps. An evolution towards a much more centered distribution of the centroid was observed with the arc power decrease during the hot-topping phase. Possible implications of the observed arc dynamics on the final quality of the VAR ingot are discussed.

Novel ideas, products, and technologies are critical for economic growth and firm competitiveness. However, many ideas do not reach the implementation stage because key audiences are not able, or n...

Jourdan develops the notion of institutional footprint of organizations and provides an empirical illustration of how footprints vary in depth and availability. He discusses the contribution of this notion for the study of materiality in institutional theory and considers its implications for the understanding of organizations and institutions.

The paper presents a generic approach to the supervised sentiment analysis of social media content in Slavic languages. The method proposes translating the documents from the original language to English with Google’s Neural Translation Model. The resulted texts are then converted to vectors by averaging the vectorial representation of words derived from a pre-trained Word2Vec English model. Testing the approach with several machine learning methods on Polish, Slovenian and Croatian Twitter datasets returns up to 86% of classification accuracy on the out-of-sample data.

Two maraging steel rods with different sulfur content, deliberately seeded with alumina (Al2O3) inclusions, were remelted in an electron beam furnace. The aim was on one hand to highlight the emergence of non-metallic inclusions at the liquid metal surface and on the other hand to study the effect of the presence of a surface active element (sulfur) on their behavior. The in situ real time observation of Al2O3 clusters was possible using both high-speed video and infrared thermography. The inclusions emerge and tend to collide and quickly agglomerate into rafts. A semi-quantitative analysis confirmed that almost 100% of inclusions are captured at the free surface. The electron beam creates large thermal gradients in the impingement zones; this induces thermocapillary convection (Marangoni effect). The flow direction depends on the sulfur content. This tendency was well-observed by following the trajectories of inclusion rafts.

We explore how the social media attention received by a firm implicated in a large corporate scandal affects the market value of its competitors. Existing work provides contrasted arguments and evidence regarding the spillover effects of scandals: rivals may suffer from contamination and at the same time benefit from substitution. Building on and extending prior work, we develop a stylized model to predict how contamination and substitution interact and jointly affect firms’ value in a non-linear way during the course of a scandal. We test our model using unique data, including 1.2m tweets, on the Dieselgate scandal that affected the global automobile industry in 2015. We find evidence of an inverted-U shape relationship between social media attention and rival firms’ value at the global scale, suggesting that substitution dominates on average. Yet the pattern is reversed for German and other European firms, primarily affected by contamination. We discuss how the study contributes to the literature on corporate scandal and disapproval, with implications for the understanding of the impact of social media on organizations.

In accreditation, candidates are evaluated against a standard for being admitted to a closed category, such as a profession or an organizational grouping. Accreditors typically have to simultaneous...

International audience; Existing research provides contradictory insights on the effect of public sponsorship on the market performance of organizations. We develop the nascent theory on sponsorship by highlighting the dual and contingent nature of the relationship between public sponsorship and market performance. By arguing that sponsorship differentially affects resource accumulation and allocation mechanisms, we suggest two opposing firm-level effects, leading to an inverted U-shaped relationship between the amount of public sponsorship received and the market performance of sponsored organizations. This non-linear relationship, we argue, is moderated by the breadth, depth and focus of the focal organization's resource accumulation and allocation patterns. While horizontal scope (i.e. increased breadth) and externally oriented resource profile (i.e. reduced depth) strengthen the relationship, market orientation (i.e. increased focus) attenuates it. We test and find strong support for our hypotheses using population data on French film production firms from 1998 to 2008. Our work highlights the performance trade-offs associated with public sponsorship, and carries important managerial and policy implications.

The world of work is changing. A century after moving from an agriculture-centered world to an Industrial one, from self-employed workers to salaried employees, our modern economies are slowly transitioning towards a new model: based on simultaneous collaboration and competition, the boundaries of contemporary organizations are blurring; information technologies are allowing individuals and companies to set base away from cities; shared working spaces are triggering new forms of collaborations between individuals and corporations.This White Paper aims at diagnosing key institutional tensions related to new work practices in the city, and putting forward questions and general propositions likely to overcome these tensions. The idea is to analyze how new collaborative communities and collaborative logics (of coworkers, hackers, makers, fabbers, and teleworkers) and more traditional collective activity and modes of decision making (of the city and corporations in the city) can jointly contribute to the co-production of harmonious new ways of life and new ways of working. Reinventing joint public policies, corporate strategies and citizenship appear here as a key stake where usual dichotomies between private-public, collaborative-non-collaborative economy, traditional citizens and hacktivists need to be overcome.We thus identify in this document a set of controversies around four strong political issues both for the city and the field of management, linked to the emergence of collaborative spaces:o Topic 1. Space, territories, and public policy on collaborative communities in the city;o Topic 2. Collaborative communities and their roles in education in the city;o Topic 3. Business models and their communication in the context of collaborative spaces and collaborative communities;o Topic 4. Collaborative spaces and their roles in innovation and entrepreneurial dynamics at the level of the cityBeyond our controversies, we underline three paradoxes which should be at the heart of new questions for policy-makers, hacktivists, actors of collaborative movements, and citizens (distinctions which may become less and less relevant in the years to come):o Social versus economic orientations of both the city and the collaborative communities it can host;o Critical/revolutionary versus more incremental relationships between cities, organizations, societies, collaborative communities, and new work practices;o Local territory (district/proximate area) grounded versus broader city-oriented or connectivity related issues about collaborative movement and new work practices.To balance these tensions, we elaborate seven general areas of questions and propositions for all stakeholders:o The generalization of infra-organization (physical collaborative platforms);o The emergence of “ ‘inclusive lab’ labels” (elaborated and managed by collaborative communities themselves);o A renewed academic presence in the city and in the country-side (with more virtual, distributed and ‘experiential’ logics);o Ephemeral and mobile labs managed jointly by public, collaborative and private stakeholders;o “Open open” innovation in public and semi-public spaces of the city;o Rise of mega-spaces for creativity in the city;o Development of a global infrastructure for coworkers, mobile workers and teleworkers.These are directions we see as particularly promising to manage the tensions, paradoxes and stakes explicated by our controversies.We hope that these questions and propositions will inspire both academics, politicians, hacktivists and entrepreneurs for future collaborations on the study and joint transformation of public policies, corporate strategies, and citizenship.

International audience; To what extent do organizations respond favorably to minority participation-that is, conform to demands from minority resource suppliers that hold an unconventional logic? A favorable response to minority participation (i.e., "alternative conformity") helps decrease the influence of dominant players, alter the resource suppliers' social structure, and promote new logics, which makes alternative conformity a "son control strategy" for organizations. We expect a positive relationship between minority participation and alternative conformity and expect that relationship to be attenuated by organizations' adherence to a dominant logic, the centrality of minority logic holders, and a minority logic's institutional credit. We test and find strong support for our hypotheses using original data on investment funds in the French film industry (1994-2008).

Due to their adequate properties, zirconium alloys are the reference materials for the nuclear fuel cladding tubes of Light Water Reactors (LWR). During some hypothetical accidental High Temperature (HT) transients, the materials should experience heavy steam oxidation and deep metallurgical evolutions. This promotes Alpha-Beta phase transformations and an associated strong partitioning of oxygen/hydrogen and of the main chemical alloying elements (Nb, Sn, Fe and Cr). Moreover, it has been shown quite recently that such chemical elements partitioning during on-cooling Beta-to-Alpha transformation can strongly impact the residual mechanical properties of HT oxidized materials. Thus, it appeared that it was important to better quantify and, if possible, to compute the quite complex phase equilibrium that occurs in multi-alloyed zirconium materials in the presence of both oxygen and hydrogen. For that, systematic studies have been performed on industrial alloys, charged with oxygen and/or hydrogen. After applying different heating/cooling scenarii, both Electron Microprobe using Wave Dispersive Spectrometry (WDS) and Nuclear Microprobe using Elastic Recoil Detection Analysis (ERDA) have been applied. Finally, to support the observed chemical elements partitioning between the Alpha and Beta allotropic phases, some thermodynamic calculations have been performed thanks to the development and the use of a specific thermodynamic database for zirconium alloys called “Zircobase".

How is an evaluating audience influenced by previous evaluations made by another audience? This question is critical to individuals and organizations reaching out to multiple audiences for key resources. While extant work has suggested evaluators are influenced by previous evaluations made by their peers, we develop theory about how evaluators’ assessment of a candidate is shaped by previous evaluations made by an external (non-peer) audience. We argue that the latter represent exogenous indices that affect evaluators in two opposing ways: they positively influence peer valuation by pointing to candidates’ unobservable abilities; yet, since they are conferred by an external audience, they are also indicative of candidates’ deviation from an expected peer identity. The combination of the two opposite effects suggests an inverted U-shaped relationship between exogenous indices and peer valuation. Further, this effect is moderated by the identity proximity between audiences, and the availability of previous peer evaluations (endogenous indices). We test and find support for our arguments using unique data on the peer valuation of 9,502 academic scientists applying for research grants at a research university. Our work contributes to the understanding of valuation and socially endogenous inferences, and has implications for the management of organizations in multi-audience environments.

International audience; To increase cycle length and/or fuel burnup, several theoretical and experimental studies have been performed at CEA. Among them, prospective neutronic calculations have shown that the addition of a few weight percents of erbium into the cladding materials could be a promising alternative to the introduction of the neutronic poison directly into the nuclear fuel pellets. Thus, fabrication of homogeneous Zr-Er alloys has been assessed, at least up to 10 wt. % of erbium and, based on the as-received mechanical properties, an optimum erbium concentration ranging from 3 to 6 wt. % has been derived. However, because of the high-oxygen thermodynamic affinity of erbium, thermal treatments have to be controlled during the fabrication route to limit Er2O3 precipitation and coarsening, which may have detrimental effects on the ductility/toughness of Zr-Er alloys. In parallel, to get more fundamental insights into the underlying phase diagrams, thermodynamic studies have been devoted to experimental assessment and modeling of the Zr-Er-(H-O) system. Because of the detrimental influence of erbium on the corrosion resistance, a three-layer sandwich clad prototype has been developed using corrosion-resistant inner/outer Zr-1Nb layers to protect the intermediate Zr-Er layer from direct water exposure. Compared to a reference Zr-1Nb(O) alloy that has been subjected to the same fabrication route, the three-layer clad prototype shows limited decrease in ductility because of pre-hydriding or after high-temperature steam oxidation e.g., in the case of a loss-of-coolant accident). Moreover, the studies performed so far have shown a spectacular hydride trapping capacity of the intermediate Zr-Er layer both for hydrogen coming from nominal outer corrosion or because of massive secondary hydriding in case of the direct access of water to the Zr-Er intermediate layer. Using μ-ERDA (elastic recoil detection analysis) measurements, detailed studies of the hydrogen spatial redistribution upon thermal cycling has been done. A simple model has been successfully used to characterize the cooling rate influence on the through-wall clad thickness partitioning of hydrogen/hydrides between the three layers, after cooling from a temperature corresponding to full dissolution of hydrides

This paper deals with the presence of High Density Inclusions (HDI) in VAR melted titanium ingots. For performance and economical reasons, the elimination of these inclusions is of utmost importance for the titanium industry. However, very few studies have considered dissolution aspects of HDIs and accurate data on their dissolution rates still lack in the literature. In the present study, we investigate the mass transport driven dissolution of some HDIs (tungsten and molybdenum) in CPTi, Ti64 and Ti17 baths. This has been done by allowing the partial dissolution of cylindrical rods in molten titanium for various controlled periods of time. Dissolution rates have been determined by measuring the dimensions of these samples before and after the experiments. In some cases, the chemical composition of the solidified bath near the sample has also been measured by Scanning Electron Microscope. It has been evidenced that the dissolution kinetics depends highly on the liquid metal agitation and temperature. The results also revealed that the dissolution of both tungsten and molybdenum is higher in pure titanium than in the investigated alloys. A numerical model describing the mass transport driven dissolution was used to determine dissolution rates numerically and to compare them to experimental results.

How is the valuation of an actor by a focal audience influenced by the actor’s popularity with an alternate audience? This question is critical to individuals and organizations relying on multiple ...

In this article, we attempt to build a comprehensive theory of the intra- and inter-organizational effects of scandals. In so doing, we develop and test distinct mechanisms regarding the effects of...

We examine the effects of organizational sponsorship on firm performance by investigating the impact of subsidies as a public resource allocation mechanism in the context of French film industry. E...

Parmi les techniques de purification ultime de metaux a hauts points de fusion, le procede de refusion par bombardement electronique associe une puissance thermique garantissant la fusion du metal, et une refusion sous vide permettant l'elimination d'impuretes par distillation. Ce papier presente la technique et le potentiel d'elimination par distillation.

This study explores how and under what conditions the social status acquired in a field may influence status judgments in another field. We focus on scientists’ involvement with industry and predic...