1,722,581 research outputs found
Measuring open innovation practices through topic modelling: Revisiting their impact on firm financial performance
Full text linkDespite the popularity of open innovation in recent years, studies examining the impact of open innovation upon firm performance have shown mixed results. Previous empirical work on this topic is often based on surveys or archival sources, usually done either in isolation or in aggregate through employing proxy measures. In contrast, we employ an unsupervised learning technique (i.e., topic modelling) utilizing natural language processing to extract information on companies’ open innovation practices, creating an initial keyword basket for future development. We then revisit the relationship between open innovation practices and financial performance of firms. The results show that a firm’s overall openness level is associated with improved financial performance. More granular practices developed from our approach, however, show variations. The inverted U-shaped relationships are observed in specific open innovation practices but not in all, partly supporting the existence of the openness paradox from prior literature. The complementarity between internal R&D and individual open innovation practices also varies by practice. Further, the influence of these open innovation practices also varies by sector. Our findings prompt us to conclude that open innovation’s impact on financial performance is nuanced, and that there is no uniform set of best practices to practice open innovation effectively
Formation of Agostic Structures Driven by London Dispersion
No full textAgostic interactions between a C−H bond and a transition metal are commonly crucial in catalytic polymerization processes. Herein, a quantitative study of the nature of β-agostic interactions in a series of systems of importance in C−H bond activation reactions is reported. The analysis, characterized by the use of a coupled-cluster-based energy decomposition scheme, demonstrates that short-range London dispersion between the agostic C−H bond and the metal center plays a fundamental role in affecting the structural stability of these systems, contrary to a widely held view. These results are used to rationalize a series of previously published experimental findings
Impacts of Connected Automated Vehicles on Large Urban Road Network
No full textAs an essential component of the Cooperative Intelligent Transportation System (C-ITS), Connected Automated Vehicles (CAVs) are anticipated to play a significant role in the development of the future mobility service. This paper investigates the impacts of different penetration of CAVs on the urban road network. The investigation is carried out in a vast urban network with Simulation of Urban MObility (SUMO), a microscopic traffic simulator. The estimated factors of the network are network maximum flow, critical density, average speed, congestion duration, and roadway over-saturation degree. The Macroscopic Fundamental Diagram (MFD) has been used to estimate the maximum flow and critical density. In a simulation way, it substantiated that a road network could have less scattered MFDs, even if the traffic flow is distributed heterogeneously. The congestion duration and over-saturation degree are used to check traffic congestion. The simulation results show that applying 100% CAVs can contribute about a 13.55% increase in maximum flow. A similar trend can be found in the critical density for different CAV penetration rates. In a similar congestion situation, the network with 100% CAV driving in can carry more than 130% of the original travel demand. In terms of congestion level, even a low CAV penetration rate may significantly improve the traffic condition
London dispersion effects in the coordination and activation of alkanes in σ-complexes: A local energy decomposition study
No full textLocal energy decomposition (LED) analysis decomposes the interaction energy between two fragments calculated at the domain-based local pair natural orbital CCSD(T) (DLPNO-CCSD(T)) level of theory into a number of chemically meaningful contributions. Herein, this scheme is applied to the interaction between the transition metal (TM) and the alkane in σ-complexes. It is demonstrated that the often-neglected London dispersion (LD) energy is a fundamental component of the TM-alkane interaction for a wide range of experimentally characterized σ-complexes. LD effects determine the structure and the thermodynamic stability of σ-complexes and influence the selectivity of CH activation reactions. The magnitude of the LD energy can be modulated by increasing the size of the alkane and of the ancillary ligands on the TM. These results provide further evidence on the fundamental role that London dispersion plays in organometallic chemistry
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Predicting build density in L-PBF through in-situ analysis of surface topography using powder bed scanner technology
Full text linkThe layerwise nature of additive manufacturing (AM) allows for in-situ monitoring of the consolidate material to identify defects on the fly and produce parts with improved reliability and performance. The main challenge in this paradigm, however, is that current methods have either limited measurement throughput or produce signals that are difficult to interpret and to relate to build properties. In this work, we present a new methodology that combines high-throughput in-situ measurements during laser powder bed fusion (L-PBF) with robust and unbiased numerical image analysis to predict build density from the surface topography of the consolidated material. The method relies on high resolution and large field of view optical scans of the layer—acquired through our powder bed scanner (PBS) technology—which we segment into “superpixels” to capture local and distributed differences in surface morphology and roughness. The high accuracy of our predictions together with the fast data acquisition and analysis enabled by the PBS and the low-dimensionality of the optical dataset after segmentation make our methodology an ideal candidate for in-line monitoring of materials produced by L-PBF. In addition, the ability to indirectly deduce a specific material property—namely density—as opposed to inferring a qualitative descriptor related to it makes our methodology unique and transferable to commercial powder bed fusion processes
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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